Vitp an information transfer protocol for vehicular computing
- 格式:pdf
- 大小:293.38 KB
- 文档页数:10
计算机⽹络名词(全)计算机⽹络名词01.TCP/IP(Transmission Control Protocol/Internet Protocol)传输控制协议/⽹际协议(⼜称Internet协议)02.UDP(User Datagram Protocol)⽤户数据报协议03.FTP(File Transfer Protocol)⽂件传输协议04.TFTP(Trivial File Transfer Protocol)简单⽂件传输协议05.SMTP(Simple Mail Transfer Protocol)简单邮件传输协议06.DNS(Domain Name System)域名系统07.STP(Spanning Tree Protocol)⽣成树协议08.RSTP(Rapid Spanning Tree Protocol)快速⽣成树协议09.VLAN(Virtual Local Area Network)虚拟局域⽹10.RIP(Routing Information Protocol)路由信息协议11.IGRP(Interior Gateway Routing Protocol)内部⽹关路由协议12.OSPF(Open Shortest Path First)开放式最短路径优先协议13.DVRP(Distence Vector Routing Protocol)距离⽮量路由协议14.LSRP(Link State Routing Protocol)链路状态路由协议15.IGP(Interior Gateway Protocol)内部⽹关协议16.BGP(Border Gateway Protocol)边界⽹关协议17.IS-IS(Intermediate System to Intermediate System Routing Protocol)中间系统到中间系统的路由选择协议18.PPP(Point to Point Protocol)点到点协议19.HDLC(High level Date Link Control)⾼级数据链路控制协议20.PAP(Password Authentication Protocol)⼝令验证协议21.CHAP(Challenge-Handshake Authentication Protocol)挑战-握⼿验证协议22.ARP(Address Resolution Protocol)地址解析协议23.RARP(Reverse Address Resolution Protocol)反向地址转换协议24.ICMP(Internet Control Message Protocol)Internet控制报⽂协议25.ADSL(Asymmetrical Digital Subscriber Line)⾮对称数字⽤户线路26.DHCP(Dynamic Host Configuration Protocol)动态主机配置协议27.HTTP(Hyper Text Transfer Protocol)超⽂本传输协议28.SNMP(Simple Network Management Protocol)简单⽹络管理协议29.SGMP(Simple Gateway Monitoring Protocol)简单⽹关监控协议30.CSMA/CD(Carrier Sense Multiple Access with Collision)载波侦听多路访问/冲突检测31.CSMA/CA(Carrier Sense Multiple Access with Collision Avoidance)载波侦听多路访问/冲突避免32.ISP (Internet Service Provider)英特⽹服务器供应商32.STP(Shielded Twisted Pair)屏蔽双绞线33.ICS (Internet Connection Sharing)连接共享34.NOS (Network Operation System)⽹络操作系统35.UTP(Unshielded Twisted Pair)⾮屏蔽双绞线36.MAC(Medium Access Control)介质访问控制37.NAT(NetworkAddressTranslation)⽹络地址转换38.IDS(Intrusion Detection Systems)⼊侵检测系统39.MIB(Management Information Base)管理信息库40.IEEE(Institute of Electrical and Electronics Engineers)电⽓和电⼦⼯程师学会缩写TCP/IPUDPFTPTFTPSMTPDNSSTPRSTPVLANRIPIGRPOSPFDVRPLSRPIGPBGPIS-ISPPPHDLCPAPCHAPARPRARPICMPADSLDHCPHTTPSNMPSGMPCSMA/CDCSMA/CAISPSTPICSNOSUTPMACNATIDSMIBIEEE项⽬1习题1.下列属于⽹络应⽤的是(ABCD)。
软考网络工程师常用英文单词和缩写翻译DARPA国防高级研究计划局ARPARNET(Internet)阿帕网ICCC国际计算机通信会议CCITT国际电报电话咨询委员会SNA系统网络体系结构(IBM)DNA数字网络体系结构(DEC)CSMA/CD载波监听多路访问/冲突检测(Xerox)NGI下一代INTERNETInternet2第二代INTERNETTCP/IP SNA SPX/IPX AppleTalk网络协议NII国家信息基础设施(信息高速公路) GII全球信息基础设施MIPSPC的处理能力Petabit10^15BIT/SCu芯片:铜OC48光缆通信SDH同步数字复用WDH波分复用不对称数字用户服务线HFE/HFC结构和Cable-modem 机顶盒PCS便携式智能终端CODEC编码解码器ASK(amplitude shift keying)幅移键控法FSK(frequency shift keying)频移键控法PSK(phase shift keying)相移键控法NRZ (Non return to zero)不归零制PCM(pulse code modulation)脉冲代码调制nonlinear encoding非线性编程频分多路复用TDM时分多路复用STDM统计时分多路复用DS064kb/sDS124DS0DS1C48DS0DS296DS0DS3762DS0DS44032DS0CSU(channel service unit)信道服务部件SONET/SDH同步光纤网络接口LRC纵向冗余校验CRC循环冗余校验ARQ自动重发请求ACK确认NAK不确认preamble前文postamble后文ITU国际电信联合会character-oriented 面向字符bit-oriented面向位SYNC同步字符HDLC面向位的方案SDLC面向位的方案bit-stuffing位插入STP屏蔽双绞线UTP非屏蔽双绞线RG-58A/U标准RG-11用于10BASE5RG-59U75欧0.25INCH CATVRG-62U9欧0.25INCH ARCnet10BASE5IEEE802.3RG-59U0.25inch CATVRG-62U0.25inch ARCnetLED(light emitting diobe)发光二级管ILD(injection laster diobe)注入型激光二级管PIN检波器APD检波器intensity modulation亮度调制line of sight可视通路CCITT V.28(EIA RS232C)非平衡型CCITT V.10/X.26(EIA RS423A)新的非平衡型CCITT V.11/X.27(EIA RS422A)新的平衡型TD发送数据RD接收数据XON/XOFF流控制Automatic Repeat Request Protocol自动重发请求Send and wait ARQ:continuousARQ停等ARQWard Christensen人名Kermit协议circuit switching线路交换packet switching分组交换virtual circuit虚电路ATM(asynchronous transfer mode)异步传输模式ATDM异步时分多路复用packetizer打包器VPI(vritual path identifier)虚路径标识VCI(virtual channel identifier)虚通道标识syntax语法semantics语义timing定时OSI(open system interconnection)开放系统session会话synchronization同步activity management活动管理AE应用实体UE用户元素CASE公共应用服务元素SASE特定应用服务元素VT虚拟终端JIM作业传送和操作reverved保留echo回送discard丢弃active users活动用户daytime白天netstat(who is up of NETSTAT)qotd(quote of the day)日期引用chargen(character generator)字符发送器nameserver(domani name server)域名服务器bootps(bootstrap protocol server/client)引导协议服务器/客户机tftp(trivial file transfer)简单文件传送sunrpc(sun microsystems RPC) SUN公司NTP:network time protocol网络时间协议SNMP(SNMP net monitor)SNMP网络监控器SNMP traps陷井biffunix comsatdaemone.g timed daemonsyslogsystem logURG紧急字段可用ACK确认字段可用PSH请求急迫操作RST连接复位SYN同步序号FIN发送方字节流结束Manchester曼彻斯特编码FDDI(fiber distributed data interface)光纤分布数据接口TTRT目标标记循环时间aggregation of multiple link segments 多重链接分段聚合协议MAN(metropolitan area network plus)城域网CSMA/CD(carrier sense multiple access/collision detection)载波监听Token bus令牌总线Token ring令牌环SAP服务访问点request indictaion response confirmationLLC PDULLC协议数据单元DSAP address目地服务访问点地址字段SSAP address源服务访问点地址字段XID交换标识SABME置扩充的异步平衡方式DISC断开连接DM断开FRMR帧拒收solt time时间片AUI连接单元接口MAU介质连接接口MDI介质相关接口PMA物理介质接口SFD起始定界符PAD填充字段FCS帧校验序列PLS物理层收发信号slot time时间Inter Frame Gap帧attempt limit最大重传次数back off limit避免算法参数Jam size阻塞参数max frame size最大帧address size地址collaspsed backone折叠式主干网BSS基本服务集ESS扩展服务集DFW-MAC分布式基础无线MACIFS帧间空隙SIFS:短PIFS点协调DIFS分布协调CTS发送清除DQDB(IEEE802.6)分布式队列双总线TDM时分复用TMS多时分交换TSI时间片互换TST网络机构TSSST STS SSTSS TSTST网络机构PSTN公用交换电话网public switched telephone network详细PBX:private branch exchange专用交换网PABX;private automatic branch exchange 自动交换机CBX:computerized branch exchange程控交换SLIP:serial line IP串行IPLCP(link control protocol)链路控制协议NCP:network control protocol网络控制协议BRI基本速率接口PRI群速率接口LAPB:line access protocol balanced链路访问协议平衡registration登录interrupt中断LAP F link access procedure for frame-mode bearer serives 太长了rotate不知道recovery恢复discard丢弃retransmission重传switched access交换访问intergated access集成访问alerting警告progress进展AALATM适配层GFC总流控cell rate decoupling 信元率去耦SDH同步数字级PDH准国步数字级GSM:group special mobile移动通讯NSS网络子系统OMC-R操作维护中心BSS基站子系统BSC基站控制器BTS基站收发信机MS移动站SIM:subscriber identity module标识模块MSC移动交换机HLR归属位置寄存器VLR访问位置寄存器AUC鉴权中心EIR设备识别寄存器OMC-S操作维护中心SC短消息中心WAP无线应用协议WAE无线应用层WSP会话层WTP事务层WTLSWDP传输层MAP移动应用部分WML无线标记语言SSL:secure sockets layer安全套接层PCS个人通信业务PCN个人通信网GEO对地静止轨道NON-GE0(MEO,LEO)不清楚ITU国际电信联盟VSAT:very small aperture -terminal甚小天线终端低轨道卫星通信系统repeater中继器bridge网桥router路由器gateway网关ONsemble stackable 10BASE 可叠加组合型集线器transparent bridge传输桥source routing bridge源路径桥broadcast storm广播风暴encapsulation封装translation bridging转换桥接方式SRT源地址选择透明桥offset偏移more flag标识ICMPINTERNET控制报文协议SPF:shortest path first最短路径IGP:interior gateway protocol核心网关协议EGP:exterior gateway protocol扩展网关协议RIP:routing information protocol路由信息协议OSPF开放最短径优先协议acquisition request获取请求acquisition confirm获取确认cease中止poll轮询IPX/SPX internetwork packet exchange/sequented packet exchange NOVELLinterpreter解释器redirector重定向器SFT system fault tolerant系统容错ELS entry level solution不认识ODI开放数据链路接口NDIS network device interface specification 网络设备接口...DDCS数据库管理和分布数据库连接服务DCE:distributed computing environment分布计算环境OSF:open software foundation开放软件基金PWS:peer web serviceWEB服务器OEM原始设备制造商RAS远程访问服务IIS:Internet Information serverINTERNET信息服务WINS:windows internet name systemWINDOWS命名服务NTDS:windows NT directory serverNT目录服务TDI传输驱动程序接口schedule++应用程序,预约本COSE:common open software environment 普通开放软件环境RPC远程过程调用SNMP:simple network management protocol 简单网管协议SMI:structer of management information管理信息结构SMT:station management管理站SMTP:simple mail transfer protocol简单邮件传输协议SNA:system network architectureIBM网络SNR:signal noise ratio信噪比SONENT:synchronous optical network 同步光纤网络SPE:synchronous payload envelope同步PAYLOAD信CMIS/CMIP公共管理信息服务/协议CMISE公共管理信息服务agent代理IMT:inductive modeling technology 不知道plaintext明文ciphertext脱密encryption加密decryption解密symmetric key cryptography对称加密asymmetric key cryptography不对称加密public key公钥private key私钥DES:data encryption standard数据加密标准IDEA:international data encryption algorithm 国际加密算法PIN:personal identification number个人标识符session key会话层密钥KDC:key distribuetion center密钥分发中心签名seal封装certificate证书certificate authority CA证书权威机构OSF开放软件中心AFS:andrew file system分布式文件系统ticket凭证authenticatior身份认证timestamp时间标记reply attack检测重放攻击域PKI公钥基础设施certificate hierarchy证书层次结构across certificate交叉证书security domain安全领域cerfificate revoke list(CRL)证书层次结构LDAP:light weight directory access protocol 协议access matrix访问矩阵ACL:access control list访问列表reference monitor引用监控器course grained粗粒度访问控制medium grained中粒度访问控制fine grained细粒度访问控制CORBA面向对象的分布系统应用MQ报文队列VPN虚拟专网IPSEC:IP security安全IPSA:security association安全??encopulation security payload 封装安全负载AH:authentication header鉴别报头IKE:Internet key exchange交换rogue programs捣乱程序IPSP:IP security protocol安全IKMP:internet key managemetn protocol 协议IESGInternet工程领导小组SHA安全散列算法MAC:message authentication code代码CBC密码块链接SSL安全套接层协议cerfificate verify证书检验报文私用强化邮件PGP:pretty good privacy好的private保密authenticated已认证SEPP安全电子付费协议SET安全电子交易middleware中间件GSS-API通用安全服务SNP安全网络编程BWD:browser web database 浏览WEB插入件basic authentication scheme不知道digest authentication scheme摘要认证方法open group:the open group research institute研究所DCE:distributed computing environment分布式计算机环境SLP:secure local proxy安全局部代理SDG:secure domain proxy安全域代理OMG:object management group目标管理组CORBS:common object request broker architecture 不清楚authentication鉴别access control访问控制data confidnetiality保密data integrity数据完整性non-reputation防止否认enciphermant加密机制digital signature mechanisms数据完整性authentication mechanisms路由控制机制notarization mechanisms公证trusted function可信security labels安全标记event dectection事件检测security audit trail安全审计跟踪security recovery安全恢复TCSEC:trusted computer system evaluation criteria标准TCSEC TNI:trusted network interpretation of the TCSEC 标准TCSEC TDI:trusted database interpretation of the TCSEC 标准ITSEC:information technology security evaluation。
常用网络名词缩写解释:TCP--- TransmissionControlProtocol 传输控制协议TCP 是一种面向连接(连接导向)的、可靠的、基于字节流的运输层(Transportlayer )通信协议ICMP---是(InternetControlMessageProtocol )Internet 控制报文协议。
它是TCP/IP 协议族的一个子协议,用于在IP 主机、路由器之间传递控制消息UDP--- UserDatagramProtocol 的简称,中文名是用户数据报协议,是OSI 参考模型中一种无连接的传输层协议,提供面向事务的简单不可靠信息传送服务NNTP---网络新闻传输协议。
这是一个主要用于阅读和张贴新闻文章(俗称为“帖子”,比较正式的是“新闻组邮件”)到Usenet 上的Internet 应用协议,也负责新闻在服务器间的传送。
SNMP--- (Simple Network ManagementProtocol,简单网络管理协议)的前身是简单网关监控协议(SGMP),用来对,用来对通信线路通信线路进行管理。
IGP---内部网关协议SNTP---简单网络时间协议(SNTP :SimpleNetworkTimeProtocol)SimpleNetworkTimeProtocol)SNTP SNTP V4由NTP 改编而来,主要用来同步因特网中的计算机时钟。
IGRP---是一种动态距离向量是一种动态距离向量路由路由协议,它由Cisco 公司八十年代中期设计。
使用组合用户配置尺度,包括延迟、带宽、可靠性和负载。
缺省情况下,IGRP 每90秒发送一次秒发送一次路由路由更新广播,在3个更新周期内(即270秒),没有从路由中的第一个从路由中的第一个路由器路由器接收到更新,则宣布路由不可访问。
PPP---点对点协议点对点协议(PPP :Point to Point Protocol ) 点对点协议(PPP )为在点对点连接上传输多协议数据包提供了一个标准方法。
Access Control访问控制Ad Hoc 移动自组织主动射频系统Active RFID SystemActive Tag 有源标签, 或称为主动标签Agile Reader 灵敏解读器Amplitude 振幅Analog Data 模拟数据Antenna 天线自动数据获取Automatic data capture自动识别Automatic Identification自动识别和数据采集 Automatic Identification and Data Collection (AIDC)反射散布Back ScatterBarcode 条形码 Bluetooth 蓝牙技术业务流程 Business Process载波讯号 Carrier SignalCloud computing 云计算 Check Digit 校验位 Container 集装箱Control Module 控制模块 Coupling 耦合数据载体 Data Carrier数据采集 Data CollectionData Entry 数据输入Data Field 数据段Data Standard 数据标准数据结构Data Structure数据段简称Data TitlesDecode 解码模块分布式结构 Distributed Architecture分发中心Distribution Center储运单元代码 DUN-14 (Dispatch Unit Number)Dynamic Data 动态数据国际物品编码协会EEAN InternationalElectromagnetic Compatibility (EMC)电磁兼容能力电磁干扰 Electromagnetic Interference (EMI)电磁波频谱 Electromagnetic SpectrumElectromagnetic Waves 电磁波商品电子防盗系统 Electronic Article Surveillance (EAS)电子数据交换 Electronic Data Interchange (EDI)Electronic Invoice电子发票电子产品码Electronic Product Code (EPC)Encode 编码Enterprise Application Integration (EAI)企业应用集成企业资源规划 Enterprise Resource Planning (ERP)(EPCIS) EPC信息服务EPC Information Service欧洲商品编码European Article Numbering (EAN)可扩展标Extensible Markup Language (XML)识语言扩展位Extension DigitFFast Moving Consumer Goods 速消费品FCC 美国联邦传播委员会Firmware 固件集成电路Integrated Circuit (IC)International Standards Organization (ISO)国际标准化组织联合国国际电信联盟 International Telecommunications Union (ITU)Internet of things物联网可视传输技术Line-of-sight Technology物流Logistics低频Low Frequency (LF)Magnification 放大系数Manufacturer 制造商Manufacturer’s ID 制造商标识Manufacturer’s Number 制造商代码Micro-Electro-Mechanism System(MEMS) 微机电系统 Microchip 微芯片Micron 微米Microwave Tags 微波标签Middleware 中间件Modulation 调制Multiple Access Schemes多路配置Multiplexer 多路转换器Name mapping 名称映射Name resolution 名称解析名称服务器资源记录 Name server resource datagramNamed pipe 命名管道Namespace 名称空间Naming context 命名上下文Naming service 命名服务网络访问服务器NAS, network access serverNetwork bridge 网桥Network card driver网卡驱动程序Network DDE service 网络 DDE 服务Network driver 网络驱动程序Network driver interface specification (NDIS)网络驱动程序接口规范 Network gateway 网关Network ID 网络 IDNetwork media 网络媒体Network Name resource 网络名称资源网络新闻传输协议 Network News Transfer Protocol (NNTP)Network number 网络号网络分区Network partition网络/位掩码标识符 Network/bit-masked identifierNetwork-to-network interface, NNI网络对网络接口NFS, network file system网络文件系统网络信息服务 NIS, Network Information Service网络对网络接口 NNI, network-to-network interface网络新闻传输协议 NNTP, Network News Transfer Protocol对象名解析服务Object Naming Service (ONS)平台即服务Platform as a Service (PaaS)Passive RFID system被动射频系统Passive Tag 无源标签, 或称被动标签物理标识语言 Physical Markup Language (PML)Platform 平台PML Server 物体标示语言服务器PML Server 服务器Protocol 协议Prototype 原型近距离传感器Proximity SensorPublic key 公钥公钥密码系统Public key cryptographyPublic Key Cryptography Standards (PKCS)公钥密码系统标准公钥基础结构Public key infrastructure ( PKI)公共电话交换网络 Public Switched Telephone Network (PSTN)Quality of Service (QoS)服务质量无线电频谱Radio Frequency SpectrumRadio Frequency Identification (RFID)射频识别Radio Wave 射频信号Read Range 解读范围Read Rate 读取速度Reader 解读器, 或称阅读器, 读写器解读器冲突Reader CollisionReader Field 解读器区域Read-Only Tag 只读标签Read-Write Tag 读写标签精简指令集计算 Reduced instruction set computing (RISC)Redundant Array of Independent Disks (RAID)独立磁盘冗余阵列 Router 路由器Routing 路由在 IPX 上的路由信息协议 Routing Information Protocol over IPX (RIPX)路由链接Routing link路由链接成本Routing-link cost路由协议Routing protocolRouting services路由服务资源保留协议 RSVP, Resource Reservation ProtocolRTP, Real-time TransportProtocol 实时传输协议软件即服务Software as a Service (SaaS)半主动射频系统Semi-passive RFID SystemSemi-Passive Tag半无源电子标签, 或称半被动式电子标签 Sensor 感应器同时识别功能Simultaneous identificationSmart Card 智能卡Smart Label 智能标签静态数据Static Data传输控制协议/网际协议 Transmission Control Protocol/Internet Protocol (TCP/IP)简单文件传输协议Trivial File Transfer Protocol (TFTP)Temporal Data 暂态数据Transmitter 发射器Transponder 转发器UUHF 超高频美国统一代码协会Uniform Code Council (UCC)通用产品代码Uniform Product Code (UPC)字符系统UCS, Unicode Character System Unicode用户数据报协议UDP, User Datagram Protocol通用串行总线USB, universal serial bus虚拟信道标识符Virtual channel identifier (VCI)虚拟容器Virtual container虚拟 DOS 机器(VDM)Virtual DOS machine虚拟 IP 地址Virtual IP address虚拟链接Virtual link虚拟局域网Virtual local area network (VLAN)Virtual memory 虚拟内存通过 IP 协议的语音 Voice over Internet Protocol (VoIP)Wafer 晶片Wide Area Network (WAN) 广域网联网行业常用技术名词1、蓝牙是一种支持设备短距离通信(一般10m内)的无线电技术。
第一章计算机基础Computer计算机Client客户机Server服务器Peer To Peer对等,P2P计算机辅助工程:Computer Aided Design CAD计算机辅助设计Computer Aided Manufacturing CAM计算机辅助制造Computer Aided Engineering CAE计算机辅助工程Computer Aided Instruction CAI计算机辅助教学Computer Aided Testing CAT计算机辅助测试GIS地理信息系统计算机分类:Mainframe大型主机Minicomputer小型计算机/迷你电脑Personal Computer个人计算机,Microcomputer微型计算机Workstation工作站Supercomputer巨型计算机/超级计算机Minisuper小巨型计算机/小超级计算机服务器按处理器体系结构划分:Complex Instruction Set Computer CISC复杂指令集计算机Reduced Instruction Set Computer RISC精简指令集计算机Very Long Instruction Word VLIW超长指令字Explicitly Parallel Instruction Computing EPIC清晰并行指令计算/简明平行指令计算Intel Architecture IA英特尔架构Blade Serer刀片式服务器计算机分类:Server服务器Workstation工作站Desktop PC台式机Notebook笔记本,Mobile PC便携机/移动PCHandheld PC掌上电脑,Sub-Notebook亚笔记本Ultra Mobile PC UMPC超便携计算机PDA个人数字助理LCD液晶显示器Serial Advanced Technology Attachment SATA串行高级技术附件Serial Attached SCSI串行SCSI硬盘Redundant Array Of Independent Disks RIAD独立磁盘冗余阵列,Disk Array磁盘阵列计算机的技术指标:Million Instruction Per Second,MIPS,单字长定点指令的平均执行速度Million Floating Instruction Per Second,MFLOPS,单字长浮点指令的平均执行速度Bits Per Second,Bps,每秒传输位数Mean Time Between Failure,MTBF,平均无故障时间Mean Time To Repair,MTTR,平均故障修复时间奔腾芯片的技术特点:Superscalar超标量Superpipeline,超流水线Peripheral Component Interconnect,PCI,外围部件互联Video Electronic Standard Association,VESA,视频电子标准协会Streaming SIMD Extension,SSE,流式的单指令流、多数据流扩展指令Mainboard主板、主机板,Motherboard,母版Adapter Card网卡、适配卡软件按授权方式分类:Commercial-Ware商业软件Share Ware共享软件Freeware自由软件信息的形式:Number数字Text文本Graphic图形Image图像Sound声音Media媒体Multimedia多媒体Videodisk视频光盘Speech语音Audio音响Multimedia PC,MPC,多媒体计算机Media Player媒体播放器Sound Recorder录音机Object Linking And Embedding,OLE,对象链接和嵌入数据压缩编码方法:Source Coding源编码Hybrid Coding混合编码Entropy Coding信息熵编码法Huffman Coding哈尔曼编码Run Length Coding游程编码Arithmetic Coding算术编码Prediction Coding预测编码法Differential Pulse Code Modulation,DPCM,微分脉码调制Delta Modulation,DM,Δ调制Transformation Coding变换编码法Discrete Fourier Transform,DFT,离散傅里叶变换Discrete Cosine Transform,DCT,离散余弦变换Discrete Hadamard Transform,DHT,离散哈达玛变换Vector Quantization Coding矢量量化编码法Joint Photographic Experts Group,JPEG,联合图像专家组International Organization For Standardization,ISO,国际标准化组织CCITT国际电报电话咨询委员会Baseline Sequential Codec基线顺序编解码Moving Picture Experts Group,MPEG,运动图像专家组HDTV高清晰度电视ITU国际电信联盟ISDN综合业务数字网IECNode结点Link链接Streaming Media流媒体第二章网络技术基础Advanced Research Projects Agency,ARPA,美国国防部高级研究计划局System Network Architecture,SNA,系统网络体系结构Distributed Computer Architecture,DCA,数字网络体系结构Open System Interconnection,OSI,开放系统互连Ethernet以太网Token Bus令牌总线Token Ring令牌环Fiber Distributed Data Interface,FDDI,光纤分布式数据接口National Information Infrastructure,NII,国家信息基础设施Global Information Infrastructure Committee,GIIC,全球信息基础设施委员会B-ISDN宽带业务综合数据网ATM异步传输模式IEEE美国电子电气工程师协会PSTN公用电话交换网CNNIC中国互联网网络信息中心计算机网络按覆盖的地理范围分类:Local Area Network,LAN,局域网Metropolitan Area Network,MAN,城域网Wide Area Network,WAN,广域网CATV有线电视网Nyquist奈奎斯特Shannon香农Circuit Switching电路交换Store-And-Forward Switching存储转发交换Message Switching报文交换Packet Switching报文分组交换Datagram,DG,数据报Virtual Circuit,VC,虚电路Message报文Packet报文分组Protocol协议Network Architecture计算机网络体系结构Implementation实现Interconnection互连性Interoperation互操作性Portability可移植性Service Definition服务定义Protocol Specification协议规格说明Physical Layer物理层Data Link Layer数据链路层Network Layer网络层Transport Layer传输层Session Layer会话层Presentation Layer表示层Application Layer应用层End-To-End端到端User Agent用户代理FTAM文件传送访问和管理VT虚拟终端TP事务处理RDA远程数据库访问MMS制造业报文规范Intercommunication互通Internet Layer互联层Host-To-Network Layer主机-网络层Transport Control Protocol,TCP,传输控制协议User Datagram Protocol,UDP,用户数据报协议Byte Stream字节流Byte Segment字节段Telnet远程登录协议File Transfer Protocol,FTP,文件传输协议Simple Mail Transfer Protocol,SMTP,简单邮件传输协议Domain Name Service,DNS,域名服务Router Information Protocol,RIP,路由信息协议Network File System,NFS,网络文件系统Hypertext Transfer Protocol,HTTP,超文本传输协议Page页面Web Site Web站点CERN欧洲粒子物理实验室Podcast播客Blog,Weblog博客,网络日志,网志Internet Protocol Television,IPTV,互联网协议电视/网络电视:Video On Demand,VOD,视频点播技术Live TV直播电视Time Shift TV时移电视Instant Messaging,IM,即时通信Wireless MAN,WMAN,无线城域网Bluetooth蓝牙Personal Operating Space,POS,个人操作空间Personal Area Network,PAN,个人区域网络Wireless Personal Area Network,WPAN,无线个人区域网络Mobile Ad Hoc Network,MANET,移动Ad Hoc网络Wireless Sensor Network,WSN,无线传感器网络Packet Radio Network,PRNET,分组无线网第三章局域网基础Fast Ethernet,FE,快速以太网Gigabit Ethernet,GE,千兆以太网Collision冲突Media Access Control,MAC,介质访问控制Logical Link Control,LLC,逻辑链路控制WG工作组TAG技术行动组Carrier Sense Multiple Access With Collision Detection,CSMA/CD,带冲突检测的载波侦听多路访问Truncated Binary Exponential Backoff截止二进制指数后退延迟Unicast Address单一节点地址Multicast Address多点地址Broadcast Address广播地址FCS帧校验字段CRC循环冗余校验Registration Authority Committee,RAC,注册管理委员会Company-Id公司标识Organizationally Unique Identifier,OUI,机构唯一标识符Extended Unique Identifier扩展的唯一标识符EPROM网卡的只读存储器Share LAN共享式局域网Switched LAN交换式局域网Media Independent Interface,MII,介质独立接口Gigabit Media Independent Interface,GMII,千兆介质独立接口High Speed Study Group,HSSG,高速研究组Switched Ethernet交换式以太网Ethernet Switch以太网交换机Hub集线器Cut Through直通Store And Forward存储转发Virtual Network虚拟网络Virtual LAN,VLAN,虚拟局域网Nomadic Access漫游访问Infrared Radio,IR,红外无线Channel Encoder信道编码器Frequence Hopping Spread Spectum,FHSS,跳频扩频通信Direct Sequence Spread Spectrum,DSSS,直接序列扩频Point Coordination Function,PCF,点协调功能Distributed Coordination Function,DCF,分布协调功能Collision Avoidance,CA,冲突避免Interframe Space,IFS,帧间间隔Bridge网桥网桥按路由表的建立方法分类:Transparent Bridge透明网桥Source Routing Bridge源路由网桥Spanning Tree生成树Discovery Frame发现帧第四章服务器操作系统Network Operating System,NOS,网络操作系统Process进程File Handle文件句柄File Allocation Table,FAT,文件表Virtual File Allocation Table,VFAT,虚拟文件表High Performance File System,HPFS,高性能文件系统Basic Input/Output System,BIOS,基本输入/输出系统Graphics Device Interface,GDI,图形设备接口Application Programming Interface,API,应用编程接口Kernel内核Monolithic Kernel单内核Microkernel微内核Nanokernel超微内核Exokernel外核Hardware Abstract Layer,HAL,硬件抽象层Directory Service,DS,目录服务Network Server网络服务器Network Station网络工作站网络操作系统的基本功能:File Service文件服务Print Service打印服务Database Service数据库服务Communication Service通信服务Message Service信息服务Distributed Service分布式服务Network Management Service网络管理服务IntranetSQL结构化查询语言Graphic User Interface,GUI,图形用户界面Domain域Primary Domain Controller主域控制器Backup Domain Controller备份域控制器Thread线程Preemptive抢占式NDIS网络驱动接口规范TDI传输驱动接口Netbeui扩展用户接口Active Directory Manager活动目录管理Tree域树Forest域森林Organizational Unit,OU,组织单元Role角色DEP数据执行保护NAP网络访问保护NAT自动网络地址转换Server Core服务器内核Powershell外壳Business Intelligence,BI,商务智能Netware Core Protocol,NCP,Netware核心协议System Failure Tolerance,SFT,系统容错File Server Mirroring文件服务器镜像Transaction Tracking System,TTS,事物跟踪系统Novell Directory Services,NDS,Novell目录服务Swapping对换Independent Software Vendors,ISV,独立软件厂商Dynamic Logic Partition动态处理器备用SWA软件助手OE操作环境第五章Internet基础ISP互联网服务提供商Remote Access Server远程访问服务器Modem调制解调器ADSL非对称数字用户线路Hybrid Fiber Coaxial,HFC,混合光纤同轴电缆网Cable TV,CATV,有线电视网DDNATMNetid网络号Hosted主机号NATAddress Resolution Protocol,ARP,地址解析协议Dynamic Binding动态绑定Cache缓存区Datagram数据报Maximum Transmission Unit,MTU,最大传输单元源路由选项的分类:Strict Source Route严格源路由选项Loose Source Route松散源路由选项Time Stamp时间戳Universal Time格林尼治时间Internet Control Message Protocol,ICMP,互联网控制报文协议Source Quench源站抑制Routing路由选择Router路由器Metric度量值度量值中经常使用的特征:Hop Count跳数Bandwidth带宽Delay延迟Load负载Reliability可靠性Cost开销应用最广的路由选择协议:Routing Information Protocol,RIP,路由信息协议Open Shortest Path First,OSPF,开放式最短路径优先协议Vector-Distance,V-D,向量-距离,Bellman-FordLink-Status,L-S,链路-状态Convergence收敛CIDR无类域间寻址DHCP动态主机配置协议Qos服务质量保证TCP提供的服务的特征:Connection Orientation面向连接Complete Reliability完全可靠性Full Duplex Communication全双工通信Stream Interface流接口Reliable Connection Startup&Graceful Connection Shutdown连接的可靠建立和优雅关闭Retransmission重发Acknowledgement确认Round Trip Time,RTT,往返时间3-Way Handshake3次握手Window窗口Well-Known Port著名端口第六章Internet基本服务服务器处理多个并发请求的方案:Iterative Server重复服务器Concurrent Server并发服务器First In,First Out先进先出Daemon守护进程Master主服务器Slave从服务器Worm蠕虫互联网的命名机制:Flat Naming无层次命名机制Hierarchy Naming层次型命名机制Label标号Domain域域名解析的两种方式:Recursive Resolution递归解析Iterative Resolution反复解析资源记录的组成:Domain Name域名Time To Live,TTL,最大生存周期,有效期Type类型Class类别Value(域名的)具体值Network Virtual Terminal,NVT,网络虚拟终端Real Terminal实终端数据连接建立的模式:Active主动模式Passive被动模式电子邮件传输协议:Simple Mail Transfer Protocol,SMTP,简单邮件传输协议Post Office Protocol,POP,邮局协议Interactive Mail Access Protocol,IMAP,RFC822将电子邮件报文分为两部分:Mail Header邮件头Mail Body邮件体Multipurpose Internet Mail Extensions,MIME,多用途Internet邮件扩展MIME-Version版本号Content-Type数据类型Content-Transfer-Encoding数据编码类型Quoted-Printable打印编码World Wide Web,WWW,European Center For Nuclear Research,CERN,欧洲核物理研究中心Hyper Text Markup Language,HTML,超文本标记语言Uniform Resource Locator,URL,统一资源定位符History历史Bookmark书签Default默认状态Tag标记Attitude属性Secure Sockets Layer,SSL,安全套接层NTFS第七章网络管理与网络安全网络管理的功能:Configuration Management配置管理Fault Management故障管理Accounting Management计费管理Performance Management性能管理Security Management安全管理NME网管代理模块IETF Internet工程任务组SNMP简单网络管理协议Manager管理者Agent代理者Polling轮询Interrupt-Based基于中断MIB管理信息库Trap-Directed Polling陷入制导轮询方法CIMP公共管理信息协议Association Control Protocol,ACP,联系控制协议Remote Operation Protocol,ROP,远程操作协议Protocol Data Unit,PDU,协议数据单元NCSC国家计算机安全中心Trusted Computer Standard Evaluation Criteria可信任计算机标准评估准则Orange Book橘皮书Dos拒绝服务Ddos分布式拒绝服务DES数据加密标准DEA数据加密算法AES高级加密算法RSANIST美国国家标准和技术研究所Key Distribution Center,KDC,密钥分发中心Certification Authority,CA,认证中心信息完整性认证方法:Massage Authentication Code,MAC,消息认证码Manipulation Detection Code,MDC,篡改检测吗认证函数:Message Encryption Function,MEF,信息加密函数Massage Authentication Code,MAC,信息认证码Hash Function散列函数DSS数字签名标准Token持证MIT麻省理工学院安全电子邮件常用技术:Pretty Good Privacy,PGP,非常好的私密性Secure/Multipurpose Internet Mail Extension,S/MIME,安全/通用Internet邮件扩充Passphrase口令短语Clear-Signed透明签名Ipsec IP安全协议:Authentication Head,AH,身份认证头Encapsulation Security Payload,ESP,封装安全负载TLS运输层安全Internetwork Security Monitor,互联网安全监视器HAR主机审计记录Generic Decryption,GD,类属解密第八章网络应用技术Multicast Backbone,Mbone,组播主干网Unicast单播Broadcast广播Multicast组播IANA管理局组播的相关协议:Internet Group Management Protocol,IGMP,互联网组管理协议CGMPRouter-Port Group Management Protocol,RGMP,路由器-端口组管理协议Dense-Mode Multicast Routing Protocol密集模式组播路由协议Flooding洪泛Distance Vector Multicast Routing Protocol,DVMRP,距离矢量组播路由协议Multicast For Open Shortest Path First,MOSPF,开放最短路径优先的组播扩展协议Protocol Independent Multicast-Dense Mode,PIM-DM,独立组播密集模式Core Based Trees,CBT,基于核心的Multiprotocol Border Gateway Protocol,MBGP,多协议边界网关协议Multicast Source Discovery Protocol,MSDP,组播源发现协议Centralized Topology集中式拓扑结构Decentralized Unstructured Topology分布式非结构化拓扑Distributed Hash Table,DHT,分布式散列表Node ID结点标识符Object ID资源标识符Chum波动Hybrid Structure混合式结构Instant Messaging And Presence Protocol Working Group,IPPWG,IMPP工作小组Request For Comment,RFC,请求评论Internet Engineering Task Force,IETF,Internet工程任务组IM系统的附加功能:Voice/Video Chat音频/视频聊天Application Sharing应用共享File Transfer文件传输File Sharing文件共享Game Request游戏邀请Remote Assistance远程助理Whiteboard白板Session会话Session Initiation Protocol,SIP,会话初始化协议SIP For Instant Messaging And Presence Leverage Extension,SIMPLEExtensible Messaging And Presence Protocol,XMPP,SIP系统的组成:User Agent用户代理User Agent Client,UAC,用户代理客户机User Agent Server,UAS,用户代理服务器Proxy Server代理服务器Redirect Server重定向服务器Registrar注册服务器SIP消息的类型:Request请求Response响应SIP消息的组成:Start-Line起始行Field字段Message Body消息体Entity Header实体头Request-Line请求行Status-Line状态行Message Session Relay Protocol,MSRP,消息中断协议Presence Information呈现信息Presence Service呈现服务呈现服务包括:Presence User Agent,PUA,呈现用户代理Presence Agent,PA,呈现代理Presence Server,PS,呈现服务器Watcher申请者Set Top Box机顶盒Near Video On Demand,NVOD,就近式点播电视True Video On Demand,TVOD,真实点播电视Interactive Video On Demand,IVOD,交互式点播电视Voice Over IP,Voip,IP电话,Internet Protocol PhoneIP电话的实现方法:PC-to-PCPC-to-PhonePhone-to-PhoneIP电话的组成:Terminal终端设备Gateway网关Multipoint Control Unit,MCU,多点控制单元Gatekeeper网守Common Gate Interface,CGI,公共网关接口Page Rank网页等级Store Server存储服务器Searcher搜索器Spiders蜘蛛/搜索器Robot机器人/搜索器Crawlers爬虫/搜索器Indexer索引器Sorter排序器Repository知识库Work Stemming词干法Word Truncation截词Link popularity链接流行度Hyperlink超链接。
计算机网络中英翻译ACK (ACKnowledgement) 确认帧ADSL (Asymmetric Digital Subscriber Line) 非对称数字用户线AN (Access Network )接入网ANSI (American National Standards Institute) 美国国家标准协会AP (Access Point) 接入点API (Application Programming Interface) 应用编程接口APNIC (Asia Pacific Network Information Center) 亚太网络信息中心ARP ( Address Resolution Protocol )地址解析协议ARPA (Advanced Research Project Agency)美国国防部远景研究规划局(高级研究计划署)ARQ (Automatic Repeat reQuest) 自动请求重发ATM (Asynchronous Transfer Mode) 异步传递方式ATU (Access Termination Unit) 接入端接单元ATU-C (Access Termination Unit Central Office )端局接入端接单元ATU-R (Access Termination Unit Remote) 远端接入端接单元AUI (Attachment Unit Interface )连接接口单元AWT ( Abstract Window Toolkit )抽象窗口工具箱BECN (Backward Explicit Congestion Notification) 反向显式拥塞通知BER (Basic Encoding Rule) 基本编码规则BGP (Border Gateway Protocol) 边界网关协议BSA (Basic Service Area) 基本服务区BSS (Basic Service Set) 基本服务集BNA 宝来网络体系结构CAC (Connection Admission Control) 连接准许控制CAP (Carrierless Amplitude Phase) 无载波振幅相位调制CATV (Community Antenna TV, CAble TV) 有线电视CBR ( Constant Bit Rate )恒定比特率CCIR (Consultative Committee,International Radio) 国际无线电咨询委员会CCITT (Consultative Committee, International Telegraph and Telephone)国际电报电话咨询委员会CCP 通信控制处理机CDM (Code Division Multiplexing) 码分复用CDMA (Code Division Multiplex Access) 码分多址CNNIC (Network Information Center of China) 中国互联网络信息中心CRC (Cyclic Redundancy Check) 循环冗余检验CSMA/CD (Carrier Sense Multiple Access / Collision Detection)载波监听多点接入/碰撞检测CSU/DSU ( Channel Service Unit/Data Service Unit) 信道服务单元/数据服务单元CTD (Cell Transfer Delay) 信元传送时延DACS (Digital Access and Cross-connect System) 数字交接系统DCA 数据通信体系结构DCE (Data Circuit-terminating Equipment) 数据电路端接设备DE (Discard Eligibility) 丢弃指示DES (Data Encryption Standard) 数据加密标准DHCP (Dynamic Host Configuration Protocol) 动态主机配置协议DLCI (Data Link Connection Identifier) 数据链路连接标识符DMT (Discrete Multi-Tone) 离散多音(调制)DNS (Domain Name System) 域名系统DNA 数据网络系统结构DSL (Digital Subscriber Line) 数字用户线DSLAM (DSL Access Multiplexer) 数字用户线接入复用器DSSS (Direct Sequence Spread Spectrum) 直接序列扩频DTE (Data Terminal Equipment) 数据终端设备DVMRP (Distance Vector Multicast Routing Protocol) 距离向量多播路由选择协议DWDM (Dense WDM) 密集波分复用EGP (External Gateway Protocol) 外部网关协议EIA (Electronic Industries Association )美国电子工业协会ESP (Encapsulating Security Payload) 封装安全有效载荷ESS 伍 xtended Service Set) 扩展的服务集FCS (Frame Check Sequence) 帧检验序列FDDI (Fiber Distributed Data Interface )光纤分布式数据接口FDM (Frequency Division Multiplexing) 频分复用FEC (Forwarding Equivalence Class) 转发等价类FEC (Forward Error Correction) 前向纠错FHSS (Frequency Hopping Spread Spectrum) 跳频扩频FIFO ( First In First Out) 先进先出FQ (Fair Queuing) 公平排队FR (Frame Relay) 帧中继FSK (Frequency Shift Keying) 移频键控FTP (File Transfer Protocol )文件传送协议FTTB (Fiber To The Building) 光纤到大楼FTTC (Fiber To The Curb )光纤到路边FTTH (Fiber To The Home) 光纤到家FTTD (Fiber To The Desk) 光纤到桌面FTTZ(Fiber To The Zone )光纤到小区FTTO (Fiber To The Office) 光纤到办公室FTTF (Fiber To The Floor) 光纤到楼层GIF (Graphics Interchange Format) 图形交换格式GII (Global Information Infrastructure) 全球信息基础结构,全球信息基础设施GFC ( Generic Flow Control) 通用流量控制GSM (Group Special Mobile) 群组专用移动通信体制HDLC (High-level Data Link Control) 面向比特的链路控制规程HDSL (High speed DSL) 高速数字用户线HEC (Header Error Control) 首部差错控制HFC (Hybrid Fiber Coax) 光纤同轴混合(网)HTML (HyperText Markup Language) 超文本置标语言HTTP (HyperText Transfer Protocol) 超文本传送协议IAB (Internet Architecture Board) 因特网体系结构委员会IAC ( Interpret As Command )作为命令解释IAHC (Internet International Ad Hoc Committee )因特网国际特别委员会ICMP ( Internet Control Message Protocol )因特网控制报文协议IDEA (International Data Encryption Algorithm) 国际数据加密算法IEEE电气和电子工程师协会IESG (Internet Engineering Steering Group) 因特网工程指导小组IETF (Internet Engineering Task Force) 因特网工程部IFS (Inter Frame Space) 帧间间隔IGMP (Internet Group Management Protocol) 因特网组管理协议IGP (Interior Gateway Protocol) 内部网关协议IM (Instant Messaging) 即时传信IMAP (Internet Message Access Protocol) 因特网报文存取协议IMP ( Interface Message Processor) 接口报文处理机IP (Internet Protocol )网际协议IR (InfraRed )红外技术IRTF ( Internet Research Task Force )因特网研究部ISDN (Integrated Services Digital Network) 综合业务数字网ISO ( International Organization for Standardization )国际标准化组织ISOC (Internet Society) 因特网协会ISP ( Internet Service Provider) 因特网服务提供者ITU ( International Telecommunication Union )国际电信联盟ITU-T ( ITU Telecommunication Standardization Sector) 国际电信联盟电信标准化部门JPEG (Joint Photographic Expert Group) 联合图像专家组标准KDC (Key Distribution Center) 密钥分配中心LAN (Local Area Network )局域网LANE (LAN Emulation )局域网仿真LAPB (Link Access Procedure Balanced) 链路接入规程(平衡型)LCP (Link Control Protocol) 链路控制协议LDP (Label Distribution Protocol) 标记分配协议LLC (Logical Link Control) 逻辑链路控制LSP (Label Switched Path) 标记交换路径LSR (Label Switching Router) 标记交换路由器MAC (Medium Access Control) 媒体接入控制MAN (Metropolitan Area Network) 城域网MAU (Medium Attachment Unit) 媒体连接单元MBONE (Multicast Backbone On the InterNEt )多播主干网MBS (Maximum Burst Size )最大突发长度MCR (Minimum Cell Rate )最小信元速率 MCU (Multipoint Control Unit)多点控制单元MD (Message Digest) 报文摘要MDI (Medium Dependent Interface )媒体相关接口MIB (Management Information Base) 管理信息库MIME (Multipurpose Internet Mail Extensions) 通用因特网邮件扩充modem 调制解调器MOTIF (Message Oriented Text Interchange System) 面向报文的电文交换系统MPEG (Motion Picture Experts Group) 活动图像专家组标准MPOA (MultiProtocol Over ATM) 多协议在 ATM 上运行MPLS (MultiProtocol Label Switching) 多协议标记交换MRU (Maximum Receive Unit) 最大接收单元MSS (Maximum Segment Size) 最长报文段MTU (Maximum Transfer Unit) 最大传送单元NAK (Negative AcKnowlegement) 否认帧NAP ( Network Access Point) 网络接入点N.ISDN (Narrowband-ISDN) 窄带综合业务数字网NAT (Network Address Translation )网络地址转换NAV (Network Al location Vector) 网络分配向量NCP (Network Control Protocol) 网络控制协议NFS (Network File System) 网络文件系统NGI 下一代因特网计划NIA 网络适配器NIC (Network Interface Card) 网络接口卡、网卡NII (National Information Infrastructure) 国家信息基础结构,国家信息基础设施NLRI (Network Layer Reachability Information) 网络层可达性信息NNI (Network-Node Interface) 网络结点接口NSF (National Science Foundation) (美国)国家科学基金会NVT (Network Virtual Terminal )网络虚拟终端ODBC (Open Database Connection)开放数据库互连OSF (Open Software Fundation )开放软件基金会OSI (Open System Interconnection )开放系统互联PBX (Private Branch eXchange )用户交换机PCM (Pulse Code Modulation ) 脉冲编码调制PCN (Personal Communications Network ) 个人通信网络PCR (Peak Cell Rate )峰值信元速率PCS 个人通信服务 Personal Communications ServicePDH 准同步数字系列PDA 个人数字助理 Personal Digital AssistantPDN 公用数据网 Public Data NetworkPDU 协议数据单元 Protocol Data UnitPER 分组差错率 packet error ratePIR 分组插入率 packet insertion ratePLCP 物理层会聚协议 Physical Layer Convergence ProtocolPLR 分组丢失率 packet loss ratePMD 物理媒体相关(子层) Physical Medium DependentPPP 点到点协议 Point to Point ProtocolPPTP 点对点隧道协议PRM 协议参考模型 Protocol Reference ModelPRN 分组无线网 Packet Radio NetworkPSN 分组交换节点 Packet Switch NodePSTN 公用电话交换网 Public Switched Telephone NetworkRARP 逆向地址解析协议 Reverse Address Resolution ProtocolRAS 远程访问服务器RFC 请求评注 Request for CommentsRMON 远程网络管理Router 路由器RPC 远程过程调用 Remote Procedure CallRSVP 资源重复利用协议RTP 接收和发送端口RTS 往返样本 Round Trip SampleRTS 剩余时间标签SAP 业务接入点 Service Access PointSAP 服务公告协议 Service Advertising ProtocolSAR 分段和重组(子层) Segmentation and ReassemblySDH 同步数字系列 Synchronous Digital HierarchySDLC 同步数据链路控制(协议) Advanced Data Communication Control Procedure SDTV 标准数字电视SDU 业务数据单元 Service Data UnitSIPP 增强的简单因特网协议 Simple Internet Protocol PlusSLIP 串行线路IP Serial Line Interface ProtocolSMDS 交换式多兆比特数据业务 Switched Multimegabit Data ServicesSMF 单模光纤 Single-mode FiberSMT 站点管理 Station ManagementSMTP 简单邮件传输协议 Simple Mail Transfer ProtocolSNA 系统网络体系结构 System Network ArchitectureSNMP 简单网络管理协议 Simple Network Management ProtocolSNR 信噪比 Signal-Noise ratioSONET 同步光纤网络 Synchronous Optical NetworkSTM 同步传输方式 Synchronous Transfer ModeSTP 屏蔽双绞线 Shielded Twisted PairSTS 同步传输信号 Synchronous Transport SignalSVC 交换虚电路 Switched Virtual CircuitSwitch 交换机TCP 传输控制协议 Transmission Control ProtocolTDM 时分多路复用 Time Division MultiplexingTFTP 单纯文件传输协议 Trivial File Transfer protocolTelnet 远程登录协议TIP 终端接口处理机 Terminal Interface ProcessorTP 双绞线 Twisted PairTSAP 传输层服务访问点 Transport Service Access PointUDP 用户数据报协议 User Datagram ProtocolUSB 通用串行总线 Universal Serial BusUTP 非屏蔽双绞线 Unshielded Twisted PairVAN 增值网 Value Added NetworkVBR 可变比特率 Variable Bit RateVCC 虚信道连接 Virtual Channel ConnectionVLAN 虚拟局域网 Virtual LANVLSI 超大规模集成电路VOD 点播图像 Video on DemandVPC 虚路径连接 Virtual Path ConnectionVPI 虚路径标识 virtual path identifierVPN 虚拟专用网络 Virtual Private NetworkVRML 虚拟现实造型语言 Virtual Reality Modeling Language VTP 虚拟隧道协议WAN 广域网 Wide Area NetworkWDM 波分多路复用 Wavelength Division MultiplexingWWW 万维网 World Wide Web。
常用网址后缀的含义在许多网站的网址中都有“com”、“net”这样的后缀,你知道这些后缀的含义吗?其实,这些后缀名就是国际顶级域名区分不同单位的方法。
下面就介绍几个常用的域名。
com 是company的缩写,代表商业组织。
gov是goverment的缩写,代表政府部门。
net 是network的缩写,代表主要网络支持中心,提供网络服务业务。
int是international的缩写,代表国际组织。
edu是education的缩写,代表教育部门。
mil 是military的缩写,代表军事部门。
org 是organization的缩写,代表社会组织,多为非赢利性的。
================================================== 网址中常见英文缩写的含义汇编表ST 股票前“ST”是特别处理的英文“special treatment”的缩写FAQ Frequently Asked Questions 的简写。
常问问题的问答集。
WWW World Wide Web的缩写,也有人戏称为World Wide Wait。
edu education 教育IP (Internet Protocol) 网际协议ISP 网络服务提供者ISO 国际标准化组织(ISO,International Organization for Stan-dardization缩写)。
IT 是指信息技术,即英文Information Technology 的缩写.EC Electronic Commerce 或E-commerce电子商务源于英文Biz business 经济缩写Com commerce 商务缩写Info infomation信息缩写Cn China 中国缩写OK okay 好的VC Venture Capital 风险资金BBS Bulletin Board System 电子公告版DnsDomainNameSystem域名系统Vip Very Important Person 贵宾Nic NETWORK INFORMATION CENTER 网络信息中心URL Uniform Resource Location 统一资源定位符BT 是一种P2P共享软件,全名叫"BitTorrent",中文全称:"比特流"又名"变态下载"DIY 是每个电脑爱好者熟悉的新名词,是英文Do It Yourself的首字母缩写,自己动手制作的意思,硬件爱好者也被俗称DIYer.OEM 是英文Original Equipment Manufacturer的缩写,意思是原设备制造商。
《交换与路由技术》模拟题A.笔试部分一、选择题1、下列对OSI 参考模型从高到低表述正确的是 CA、应用层、表示层、会话层、网络层、数据链路层、传输层、物理层B、物理层、数据链路层、传输层、会话层、表示层、应用层、网络层C、应用层、表示层、会话层、传输层、网络层、数据链路层、物理层D、应用层、传输层、互联网层、网络接口层2、在OSI 7 层模型中,网络层的功能有(B)A、在信道上传送比特流B、确定数据包如何转发与路由C、建立端到端的连接,确保数据的传送正确无误D、保证数据在网络中的传输(多)3、下列属于物理层设备的是:ADA、集线器B、交换机C、网桥D、调制解调器4、下列说法正确的是:DA、按服务方式分可将计算机网络分为客户机/服务器网络、广播式网络B、按地理位置分可将计算机网络分为局域网、城域网、省域网、广域网A、按传输介质分可将计算机网络分为双绞线网、光纤网、无线网D、按地理位置分可将计算机网络分为局域网、城域网、广域网、互联网5、路由器工作在OSI 参考模型的哪一层? DA、应用层B、传输层C、表示层D、网络层6、下列对双绞线线序568A 排序正确的是:AA、白绿、绿、白橙、兰、白兰、橙、白棕、棕B、绿、白绿、橙、白橙、兰、白兰、棕、白棕C、白橙、橙、白绿、兰、白兰、绿、白棕、棕D、白橙、橙、绿、白兰、兰、白绿、白棕、棕7、OSI 七层模型在数据封装时正确的协议数据单元排序是:CA、packet、frame、bit、segmentB、frame、bit、segment、packetC、segment、packet、frame、bitD、bit、frame、packet、segment8、telnet 是文件传输协议,它使用的端口是 CA、21 22B、80C、23D、1399、有一个中学获得了C 类网段的一组IP 192.168.1.0/24,要求你划分7 个以上的子网,每个子网主机数不得少于25 台,请问子网掩码该怎么写?BA、255.255.255.128B、255.255.255.224C、255.255.255.240D、255.255.240.010、下列属于私有地址的是:CA、193.168.159.3B、100.172.1.98C、172.16.0.1D、127.0.0.111、下列IP 地址属于标准B 类IP 地址的是:BA、172.19.3.245/24B、190.168.12.7/16C、120.10.1.1/16D、10.0.0.1/1612、通过console 口管理交换机在超级终端里应设为 AA、波特率:9600 数据位:8 停止位:1 奇偶校验:无B、波特率:57600 数据位:8 停止位:1 奇偶校验:有C、波特率:9600 数据位:6 停止位:2 奇偶校验:有D、波特率:57600 数据位:6 停止位:1 奇偶校验:无13、下列可用的MAC 地址是:DA、00-00-F8-00-EC-G7B、00-0C-1E-23-00-2A-01C、00-00-0C-05-1CD、00-D0-F8-00-11-0A14、通常以太网采用了(D)协议以支持总线型的结构。
计算机网络中英翻译ACK (ACKnowledgement) 确认帧ADSL (Asymmetric Digital Subscriber Line) 非对称数字用户线AN (Access Network )接入网ANSI (American National Standards Institute) 美国国家标准协会AP (Access Point) 接入点API (Application Programming Interface) 应用编程接口APNIC (Asia Pacific Network Information Center) 亚太网络信息中心ARP ( Address Resolution Protocol )地址解析协议ARPA (Advanced Research Project Agency)美国国防部远景研究规划局(高级研究计划署)ARQ (Automatic Repeat reQuest) 自动请求重发ATM (Asynchronous Transfer Mode) 异步传递方式ATU (Access Termination Unit) 接入端接单元ATU-C (Access Termination Unit Central Office )端局接入端接单元ATU-R (Access Termination Unit Remote) 远端接入端接单元AUI (Attachment Unit Interface )连接接口单元AWT ( Abstract Window Toolkit )抽象窗口工具箱BECN (Backward Explicit Congestion Notification) 反向显式拥塞通知BER (Basic Encoding Rule) 基本编码规则BGP (Border Gateway Protocol) 边界网关协议BSA (Basic Service Area) 基本服务区BSS (Basic Service Set) 基本服务集BNA 宝来网络体系结构CAC (Connection Admission Control) 连接准许控制CAP (Carrierless Amplitude Phase) 无载波振幅相位调制CATV (Community Antenna TV, CAble TV) 有线电视CBR ( Constant Bit Rate )恒定比特率CCIR (Consultative Committee,International Radio) 国际无线电咨询委员会CCITT (Consultative Committee, International Telegraph and Telephone)国际电报电话咨询委员会CCP 通信控制处理机CDM (Code Division Multiplexing) 码分复用CDMA (Code Division Multiplex Access) 码分多址CNNIC (Network Information Center of China) 中国互联网络信息中心CRC (Cyclic Redundancy Check) 循环冗余检验CSMA/CD (Carrier Sense Multiple Access / Collision Detection)载波监听多点接入/碰撞检测CSU/DSU ( Channel Service Unit/Data Service Unit) 信道服务单元/数据服务单元CTD (Cell Transfer Delay) 信元传送时延DACS (Digital Access and Cross-connect System) 数字交接系统DCA 数据通信体系结构DCE (Data Circuit-terminating Equipment) 数据电路端接设备DE (Discard Eligibility) 丢弃指示DES (Data Encryption Standard) 数据加密标准DHCP (Dynamic Host Configuration Protocol) 动态主机配置协议DLCI (Data Link Connection Identifier) 数据链路连接标识符DMT (Discrete Multi-Tone) 离散多音(调制)DNS (Domain Name System) 域名系统DNA 数据网络系统结构DSL (Digital Subscriber Line) 数字用户线DSLAM (DSL Access Multiplexer) 数字用户线接入复用器DSSS (Direct Sequence Spread Spectrum) 直接序列扩频DTE (Data Terminal Equipment) 数据终端设备DVMRP (Distance Vector Multicast Routing Protocol) 距离向量多播路由选择协议DWDM (Dense WDM) 密集波分复用EGP (External Gateway Protocol) 外部网关协议EIA (Electronic Industries Association )美国电子工业协会ESP (Encapsulating Security Payload) 封装安全有效载荷ESS 伍 xtended Service Set) 扩展的服务集FCS (Frame Check Sequence) 帧检验序列FDDI (Fiber Distributed Data Interface )光纤分布式数据接口FDM (Frequency Division Multiplexing) 频分复用FEC (Forwarding Equivalence Class) 转发等价类FEC (Forward Error Correction) 前向纠错FHSS (Frequency Hopping Spread Spectrum) 跳频扩频FIFO ( First In First Out) 先进先出FQ (Fair Queuing) 公平排队FR (Frame Relay) 帧中继FSK (Frequency Shift Keying) 移频键控FTP (File Transfer Protocol )文件传送协议FTTB (Fiber To The Building) 光纤到大楼FTTC (Fiber To The Curb )光纤到路边FTTH (Fiber To The Home) 光纤到家FTTD (Fiber To The Desk) 光纤到桌面FTTZ(Fiber To The Zone )光纤到小区FTTO (Fiber To The Office) 光纤到办公室FTTF (Fiber To The Floor) 光纤到楼层GIF (Graphics Interchange Format) 图形交换格式GII (Global Information Infrastructure) 全球信息基础结构,全球信息基础设施GFC ( Generic Flow Control) 通用流量控制GSM (Group Special Mobile) 群组专用移动通信体制HDLC (High-level Data Link Control) 面向比特的链路控制规程HDSL (High speed DSL) 高速数字用户线HEC (Header Error Control) 首部差错控制HFC (Hybrid Fiber Coax) 光纤同轴混合(网)HTML (HyperText Markup Language) 超文本置标语言HTTP (HyperText Transfer Protocol) 超文本传送协议IAB (Internet Architecture Board) 因特网体系结构委员会IAC ( Interpret As Command )作为命令解释IAHC (Internet International Ad Hoc Committee )因特网国际特别委员会ICMP ( Internet Control Message Protocol )因特网控制报文协议IDEA (International Data Encryption Algorithm) 国际数据加密算法IEEE电气和电子工程师协会IESG (Internet Engineering Steering Group) 因特网工程指导小组IETF (Internet Engineering Task Force) 因特网工程部IFS (Inter Frame Space) 帧间间隔IGMP (Internet Group Management Protocol) 因特网组管理协议IGP (Interior Gateway Protocol) 内部网关协议IM (Instant Messaging) 即时传信IMAP (Internet Message Access Protocol) 因特网报文存取协议IMP ( Interface Message Processor) 接口报文处理机IP (Internet Protocol )网际协议IR (InfraRed )红外技术IRTF ( Internet Research Task Force )因特网研究部ISDN (Integrated Services Digital Network) 综合业务数字网ISO ( International Organization for Standardization )国际标准化组织ISOC (Internet Society) 因特网协会ISP ( Internet Service Provider) 因特网服务提供者ITU ( International Telecommunication Union )国际电信联盟ITU-T ( ITU Telecommunication Standardization Sector) 国际电信联盟电信标准化部门JPEG (Joint Photographic Expert Group) 联合图像专家组标准KDC (Key Distribution Center) 密钥分配中心LAN (Local Area Network )局域网LANE (LAN Emulation )局域网仿真LAPB (Link Access Procedure Balanced) 链路接入规程(平衡型)LCP (Link Control Protocol) 链路控制协议LDP (Label Distribution Protocol) 标记分配协议LLC (Logical Link Control) 逻辑链路控制LSP (Label Switched Path) 标记交换路径LSR (Label Switching Router) 标记交换路由器MAC (Medium Access Control) 媒体接入控制MAN (Metropolitan Area Network) 城域网MAU (Medium Attachment Unit) 媒体连接单元MBONE (Multicast Backbone On the InterNEt )多播主干网MBS (Maximum Burst Size )最大突发长度MCR (Minimum Cell Rate )最小信元速率 MCU (Multipoint Control Unit)多点控制单元MD (Message Digest) 报文摘要MDI (Medium Dependent Interface )媒体相关接口MIB (Management Information Base) 管理信息库MIME (Multipurpose Internet Mail Extensions) 通用因特网邮件扩充modem 调制解调器MOTIF (Message Oriented Text Interchange System) 面向报文的电文交换系统MPEG (Motion Picture Experts Group) 活动图像专家组标准MPOA (MultiProtocol Over ATM) 多协议在 ATM 上运行MPLS (MultiProtocol Label Switching) 多协议标记交换MRU (Maximum Receive Unit) 最大接收单元MSS (Maximum Segment Size) 最长报文段MTU (Maximum Transfer Unit) 最大传送单元NAK (Negative AcKnowlegement) 否认帧NAP ( Network Access Point) 网络接入点N.ISDN (Narrowband-ISDN) 窄带综合业务数字网NAT (Network Address Translation )网络地址转换NAV (Network Al location Vector) 网络分配向量NCP (Network Control Protocol) 网络控制协议NFS (Network File System) 网络文件系统NGI 下一代因特网计划NIA 网络适配器NIC (Network Interface Card) 网络接口卡、网卡NII (National Information Infrastructure) 国家信息基础结构,国家信息基础设施NLRI (Network Layer Reachability Information) 网络层可达性信息NNI (Network-Node Interface) 网络结点接口NSF (National Science Foundation) (美国)国家科学基金会NVT (Network Virtual Terminal )网络虚拟终端ODBC (Open Database Connection)开放数据库互连OSF (Open Software Fundation )开放软件基金会OSI (Open System Interconnection )开放系统互联PBX (Private Branch eXchange )用户交换机PCM (Pulse Code Modulation ) 脉冲编码调制PCN (Personal Communications Network ) 个人通信网络PCR (Peak Cell Rate )峰值信元速率PCS 个人通信服务 Personal Communications ServicePDH 准同步数字系列PDA 个人数字助理 Personal Digital AssistantPDN 公用数据网 Public Data NetworkPDU 协议数据单元 Protocol Data UnitPER 分组差错率 packet error ratePIR 分组插入率 packet insertion ratePLCP 物理层会聚协议 Physical Layer Convergence ProtocolPLR 分组丢失率 packet loss ratePMD 物理媒体相关(子层) Physical Medium DependentPPP 点到点协议 Point to Point ProtocolPPTP 点对点隧道协议PRM 协议参考模型 Protocol Reference ModelPRN 分组无线网 Packet Radio NetworkPSN 分组交换节点 Packet Switch NodePSTN 公用电话交换网 Public Switched Telephone NetworkRARP 逆向地址解析协议 Reverse Address Resolution ProtocolRAS 远程访问服务器RFC 请求评注 Request for CommentsRMON 远程网络管理Router 路由器RPC 远程过程调用 Remote Procedure CallRSVP 资源重复利用协议RTP 接收和发送端口RTS 往返样本 Round Trip SampleRTS 剩余时间标签SAP 业务接入点 Service Access PointSAP 服务公告协议 Service Advertising ProtocolSAR 分段和重组(子层) Segmentation and ReassemblySDH 同步数字系列 Synchronous Digital HierarchySDLC 同步数据链路控制(协议) Advanced Data Communication Control Procedure SDTV 标准数字电视SDU 业务数据单元 Service Data UnitSIPP 增强的简单因特网协议 Simple Internet Protocol PlusSLIP 串行线路IP Serial Line Interface ProtocolSMDS 交换式多兆比特数据业务 Switched Multimegabit Data ServicesSMF 单模光纤 Single-mode FiberSMT 站点管理 Station ManagementSMTP 简单邮件传输协议 Simple Mail Transfer ProtocolSNA 系统网络体系结构 System Network ArchitectureSNMP 简单网络管理协议 Simple Network Management ProtocolSNR 信噪比 Signal-Noise ratioSONET 同步光纤网络 Synchronous Optical NetworkSTM 同步传输方式 Synchronous Transfer ModeSTP 屏蔽双绞线 Shielded Twisted PairSTS 同步传输信号 Synchronous Transport SignalSVC 交换虚电路 Switched Virtual CircuitSwitch 交换机TCP 传输控制协议 Transmission Control ProtocolTDM 时分多路复用 Time Division MultiplexingTFTP 单纯文件传输协议 Trivial File Transfer protocolTelnet 远程登录协议TIP 终端接口处理机 Terminal Interface ProcessorTP 双绞线 Twisted PairTSAP 传输层服务访问点 Transport Service Access PointUDP 用户数据报协议 User Datagram ProtocolUSB 通用串行总线 Universal Serial BusUTP 非屏蔽双绞线 Unshielded Twisted PairVAN 增值网 Value Added NetworkVBR 可变比特率 Variable Bit RateVCC 虚信道连接 Virtual Channel ConnectionVLAN 虚拟局域网 Virtual LANVLSI 超大规模集成电路VOD 点播图像 Video on DemandVPC 虚路径连接 Virtual Path ConnectionVPI 虚路径标识 virtual path identifierVPN 虚拟专用网络 Virtual Private NetworkVRML 虚拟现实造型语言 Virtual Reality Modeling Language VTP 虚拟隧道协议WAN 广域网 Wide Area NetworkWDM 波分多路复用 Wavelength Division MultiplexingWWW 万维网 World Wide Web。
⽹络传输协议有哪些注明:以下内容复制于百度知道,本⼈⽤于学习。
TCP/IP,互联⽹传输协议。
以下为各种⽹络传输协议列表(后⾯数字表⽰应⽤层协议默认服务端⼝):AARP (ARP Address Resolution Protocol)BBGP (边缘⽹关协议 Border Gateway Protocol)蓝⽛(Blue Tooth)BOOTP (Bootstrap Protocol)DDHCP( Dynamic Host Configuration Protocol)DNS(域名服务 Domain Name Service)DVMRP (Distance-Vector Multicast Routing Protocol)EEGP (Exterior Gateway Protocol)FFTP (⽂件传输协议 File Transfer Protocol) 21HHDLC (⾼级数据链路控制协议 High-level Data Link Control)HELLO(routing protocol)HTTP 超⽂本传输协议 80HTTPS 安全超级⽂本传输协议IICMP (互联⽹控制报⽂协议 Internet Control Message Protocol)IDRP (InterDomain Routing Protocol)IEEE 802IGMP (Internet Group Management Protocol)IGP (内部⽹关协议 Interior Gateway Protocol )IMAPIP (互联⽹协议 Internet Protocol)IPXIS-IS(Intermediate System to Intermediate System Protocol)LLCP (链路控制协议 Link Control Protocol)LLC (逻辑链路控制协议 Logical Link Control)MMLD (多播监听发现协议 Multicast Listener Discovery)NNCP (⽹络控制协议 Network Control Protocol)NNTP (⽹络新闻传输协议 Network News Transfer Protocol) 119NTP (Network Time Protocol)PPPP (点对点协议 Protocol)POP (邮局协议 Post Office Protocol) 110RRARP (逆向地址解析协议 Reverse Address Resolution Protocol)RIP (路由信息协议 Routing Information Protocol)SSLIP (串⾏链路连接协议Serial Link Internet Protocol)SNMP (简单⽹络管理协议 Simple Network Management Protocol)SMTP (简单邮件传输协议 Simple Mail Transport Protocol) 25SCTP(流控制传输协议 Stream Control Transmission Protocol)TTCP (传输控制协议 Transmission Control Protocol)TFTP (Trivial File Transfer Protocol)Telnet (远程终端协议 remote terminal protocol) 23UUDP (⽤户数据报协议 User Datagram Protocol)常⽤的有以下⼏种:ARP(Address Resolution Protocol)地址解析协议 它是⽤于映射计算机的物理地址和临时指定的⽹络地址。
用户信息传输装置协议解析用户信息传输装置协议(User Information Transfer Device Protocol,简称UITD)是一种用于在计算机网络中传输用户信息的协议。
该协议定义了用户信息的格式、传输方式和相关操作规范,以确保信息的安全、可靠和高效传输。
一、协议概述用户信息传输装置协议是在计算机网络中实现用户信息传输的一种标准协议。
它建立在网络传输协议(如TCP/IP)的基础上,通过定义用户信息的格式和传输方式,使得用户可以在不同计算机之间传输和共享信息。
UITD协议主要包括信息封装、传输控制和错误处理等功能,以实现可靠的用户信息传输。
二、信息封装用户信息传输装置协议采用一种特定的封装格式来组织用户信息。
在信息封装过程中,首先要对用户信息进行分段,确保每个段的大小在网络传输的限制范围之内。
然后,对每个段进行封装,包括添加头部信息和校验码。
头部信息包含了源地址、目标地址、协议版本等重要信息,用于路由和识别。
校验码用于检测传输过程中的错误。
三、传输控制用户信息传输装置协议采用可靠传输方式,确保用户信息在网络中的正确传输。
在信息传输过程中,协议会对信息进行分组,每个分组会添加序列号和确认号,用于控制和确认传输顺序。
同时,协议还会进行流量控制,根据网络的拥塞情况调整发送速率,以避免网络拥塞和信息丢失。
四、错误处理用户信息传输装置协议具备完善的错误处理机制,以应对传输过程中可能出现的错误。
一旦发生错误,协议会通过重传机制重新发送丢失的分组,以确保信息的完整性和可靠性。
同时,协议还会对接收到的信息进行校验,检测是否有错误或篡改。
如果发现错误,协议会向发送方发送错误通知,并要求重新发送。
五、应用领域用户信息传输装置协议广泛应用于大型计算机网络中,如互联网、局域网等。
它为用户提供了一种快速、安全、可靠的信息传输方式,支持多种应用场景。
例如,电子邮件、文件传输、远程登录等。
此外,UITD协议还被广泛应用于电子商务、在线支付、社交网络等领域,为用户提供了便捷的服务。
通信电子中的网络协议技术网络协议技术是指在计算机网络中用于实现网络通信的一系列规范和协议。
它负责规定数据如何在网络中传输、交换和处理,确保不同设备和系统之间能够正确地进行通信。
网络协议技术在通信电子中起着至关重要的作用,本文将从传输协议、路由协议和应用层协议三个方面来介绍通信电子中的网络协议技术。
一、传输协议传输协议是在网络传输过程中,负责数据包的传输和传递的一种协议。
最常见的传输协议是TCP(Transmission Control Protocol)和UDP (User Datagram Protocol)。
TCP是一种面向连接的可靠数据传输协议,它将数据拆分为多个小包,并确保这些小包按照正确的顺序到达目的地。
TCP使用IP地址和端口号来标识发送和接收的应用程序。
TCP还提供拥塞控制和流量控制等功能,确保网络的稳定性和可靠性。
UDP是一种面向无连接的不可靠数据传输协议,它不提供拥塞控制和流量控制等功能,只将数据传输到目的地,不关心数据是否正确到达。
UDP适用于需要实时传输的应用,比如音视频传输、在线游戏等。
二、路由协议路由协议是在不同网络之间选择最佳路径来传输数据的一种协议。
路由协议可以帮助网络设备选择最短路径,提高数据传输的速度和效率。
常见的路由协议有RIP(Routing Information Protocol)、OSPF(Open Shortest Path First)和BGP(Border Gateway Protocol)等。
RIP是一种基于距离向量算法的内部网关协议,它通过距离和下一跳信息来确定最佳路径。
RIP适用于小型网络,但在大型网络中效率较低。
OSPF是一种基于链路状态算法的内部网关协议,它将网络中的路由器分为区域,并通过链路状态信息来选择最佳路径。
OSPF适用于大型企业网络。
BGP是一种用于互联网上的自治系统之间交换路由信息的外部网关协议,它通过自治系统之间的对等关系来选择最佳路径。
Chapter 11.1Internet:因特网Computer network :计算机网络Host: 主机End system: 终端系统Packet switching: 分组交换Route: 路径Internet service provider (ISP): 因特网服务提供商Protocol: 协议Transmission Control Protocol (TCP):传输控制协议1.2Client: 客户端Server: 服务器Peer: 对等机Reliable data transfer: 可靠数据传输Flow control: 流量控制Congestion-control: 拥塞控制User Datagram Protocol (UDP): 用户数据报协议1.3Circuit switching: 电路交换/线路交换Packet switching: 分组交换Frequency-division multiplexing (FDM): 频分多路复用Time-division multiplexing (TDM): 时分多路复用Bandwidth: 带宽Time slot: 时隙Frame: 帧Message: 报文:Packet: 分组Store-and-forward: 存储转发Datagram network: 数据报网络Virtual-circuit network: 虚电路网络1.4Router: 路由器Modem: 调制解调器Local area network (LAN): 局域网Ethernet: 以太网Wireless LAN: 无线局域网Guided media: 导向型介质Unguided media: 非导向型介质Twisted-pair copper wire: 双绞线Unshielded twisted pair(UTP): 非屏蔽双绞线Coaxial cable: 同轴电缆Fiber optics: 光线/光缆1.6Nodal processing delay: 结点处理延迟Queuing delay: 排队延迟Transmission delay: 发送延迟Propagation delay: 传播延迟Traffic intensity: 流通强度End-to-end delay: 端到端延迟1.7Layer: 层次Protocol stack: 协议栈Application layer: 应用层Transport layer: 传输层Network layer: 网络层Link layer: 链路层Physical layer: 物理层Encapsulation: 封装Message: 报文Segment: 报文段Datagram: 数据报Frame: 帧Chapter 22.1Client-server architecture: 客户端-服务器体系结构;C/S结构P2P architecture: 对等结构Processes: 进程Socket: 套接字Application programming interface (API): 应用程序编程接口IP address: IP地址Prot number: 端口号Syntax: 语法Semantics: 语义Full-duplex: 全双工Handshaking: 握手Real-time application: 实时应用2.2The World Wide Web: 万维网HyperText Transfer Protocol (HTTP): 超文本传输协议Web page: 网页Object: 对象HyperText Markup Language (HTML): 超文本标记语言URL:统一资源定位符Browser: 浏览器Persistent connection: 持久连接Non-persistent connection: 非持久连接Round-trip time (RTT): 往返时间Without pipelining: 非流水线方式With pipelining: 流水线方式Web cache: web 缓存Proxy server: 代理服务器2.3File Transfer Protocol (FTP): 文件传输协议Control connection: 控制连接Data connection: 数据连接Out-of-band: 带外In-band: 带内2.4Electronic Mail: 电子邮件User agent: 用户代理Mail server: 邮件服务器Simple Mail Transfer Protocol (SMTP): 简单邮件传输协议Mailbox: 邮箱Multipurpose Internet Mail Extensions (MIME): 多用途因特网邮件扩展协议Post Office Protocol (POP): 邮局协议Internet Mail Access Protocol (IMAP): Internet 邮件访问协议2.5 Domain Name System (DNS): 域名系统Hostname: 主机名Host aliasing: 主机别名Mail server aliasing: 邮件服务器别名Load distribution: 负载分配Root DNS server: 根DNS服务器Top-Level Domain (TLD) servers: 顶级域DNS服务器Authoritative DNS servers: 授权DNS服务器;权威DNS服务器Local DNS server: 本地DNS服务器Database: 数据库Chapter 33.1Logical communication: 逻辑通讯3.2Multiplexing: 多路复用Demultiplexing: 多路分解Well-known port number: 众所周知的端口号3.3UDP segment: UDP报文段Checksum: 校验和;检查和Wrapped around: 回卷3.4Channel: 通道;信道Positive acknowledgement : 肯定应答Negative acknowledgement: 否定应答ARQ (automatic repeat request): 自动重传请求Feedback: 反馈Retransmission: 重传Stop-and-wait protocol: 停止-等待协议Duplicate packets: 冗余分组Sequence number: 顺序号Timer: 定时器Alternating-bit protocol: 比特交替协议Utilization: 利用率Go-back-N (GBN): 回退N步Window size: 窗口大小Sliding-window protocol: 滑动窗口协议Cumulative acknowledgement: 累积确认Timeout: 超时Selective Repeat (SR): 选择重传3.5Connection-oriented: 面向连接Point-to-point: 点到点Three-way handshake: 三次握手Maximum segment size (MSS): 最大报文段大小Maximum transmission unit (MTU): 最大传输单元Piggybacked: 捎带Sample RTT: 样本RTTFast retransmit: 快速重传Selective acknowledgement: 选择确认Flow-control: 流量控制Receive window: 接收窗口3.7Congestion control: 拥塞窗口Self-clocking: 自定时的Additive-increase, multiplicative-decrease: 加性增,乘性减Slow star: 慢启动Congestion avoidance: 拥塞避免Threshold: 阈值Fast recovery: 快速恢复Bottleneck: 瓶颈Latency: 延迟Chapter 44.1Forwarding: 转发Routing: 路由Routing algorithm: 路由算法Forwarding table: 转发表Router: 路由器Jitter: 抖动Best-effort service: 尽力而为的服务4.2Virtual-circuit (VC) network: 虚电路网络Datagram network: 数据报网络Prefix: 前缀Longest prefix matching rule: 最长前缀匹配规则4.3Input port: 输入端口Switching fabric: 交换结构Routing processor: 路由处理器Crossbar: 交叉结构4.4Time-to-live (TTL) :生存时间Fragmentation: 分片;片段Dotted-decimal notation: 点分十进制表示法Subnet: 子网Subnet mask: 子网掩码Classless Interdomain Routing (CIDR): 无类别域际路由选择Dynamic Host Configuration Protocol (DHCP):动态主机配置协议Plug-and-play: 即插即用Network address translation (NAT): 网络地址转换Internet Control Message Protocol (ICMP): 因特网控制报文协议Dual-stack: 双栈Tunneling: 隧道4.5Default router: 默认路由器Graph: 图A global routing algorithm : 全局路由算法A decentralized routing algorithm : 分布式路由算法Static routing algorithm: 静态路由算法Dynamic routing algorithm : 动态路由算法Link-State (LS): 链路状态Distance-Vector(DV): 距离向量Routing table: 路由表Autonomous system (AS): 自治系统Intra-autonomous system routing protocol: 自治系统内路由协议Inter-AS routing protocol: 自治系统间路由协议4.6Interior gateway protocol: 内部网关协议Routing Information Protocol (RIP): 路由信息协议Open Shortest Path First (OSPF): 开放最短路径优先协议Advertisement: 公告Hop: 跳Border Gateway Protocol (BGP): 边界网关协议4.7Broadcast: 广播Multicast: 多播Chapter 55.1Node: 结点Link: 链路Frame: 帧Medium access control (MAC): 介质访问控制Full-duplex: 全双工Half-duplex: 半双工Adapter: 适配器Network interface card (NIC): 网卡Interface: 接口5.2Parity check: 奇偶校验Odd: 奇数Even: 偶数Cyclic redundancy check (CRC): 循环冗余校验Polynomial: 多项式5.3Collide: 冲突Multiple access protocol: 多路访问协议Channel partitioning protocol: 信道划分协议Random access protocol: 随机访问协议Taking-turns protocol: 轮转协议Code division multiple access (CDMA): 码分多址访问Carrier sensing: 载波侦听Collision detection: 冲突检测Polling protocol: 轮询协议Token-passing protocol: 令牌传递协议Token: 令牌Local Area Network (LAN): 局域网Token-ring: 令牌环Fiber distributed data interface (FDDI): 光纤分布式数据接口Metropolitan Area Network (MAN): 城域网5.4Address Resolution Protocol (ARP): 地址解析协议Dynamic Host Configuration Protocol (DHCP): 动态主机配置协议5.5Ethernet: 以太网Preamble: 前导码Manchester encoding: 曼彻斯特编码5.6Hub: 集线器Collision domain: 冲突域Switch: 交换机Filtering: 过滤Forwarding: 转发Switch table: 交换表Self-learning: 自学习Plug-and-play devices: 即插即用设备Cut-through switching: 直通式交换5.7Point-to-point: (PPP): 点到点。
软考网络工程师常用英文单词和缩写翻译DARPA国防高级研究计划局ARPARNET(Internet)阿帕网ICCC国际计算机通信会议CCITT国际电报电话咨询委员会SNA系统网络体系结构(IBM)DNA数字网络体系结构(DEC)CSMA/CD载波监听多路访问/冲突检测(Xerox)下一代INTERNETInternet2第二代INTERNETTCP/IP SNA SPX/IPX AppleTalk 网络协议NII国家信息基础设施(信息高速公路) GII全球信息基础设施MIPSPC的处理能力Petabit10^15BIT/SCu芯片:OC48光缆通信SDH同步数字复用WDH波分复用ADSL不对称数字用户服务线HFE/HFC结构和Cable-modem 机顶盒PCS便携式智能终端CODEC编码解码器ASK(amplitude shift keying) 幅移键控法FSK(frequency shift keying) 频移键控法PSK(phase shift keying)相移键控法NRZ (Non return to zero)不归零制PCM(pulse code modulation) 脉冲代码调制nonlinear encoding非线性编程FDM频分多路复用TDM时分多路复用STDM统计时分多路复用DS064kb/sDS124DS0DS1C48DS0DS296DS0DS3762DS0DS44032DS0CSU(channel service unit) 信道服务部件SONET/SDH同步光纤网络接口LRC纵向冗余校验CRC循环冗余校验ARQ自动重发请求ACK确认NAK不确认preamble前文postamble后文ITU国际电信联合会character-oriented 面向字符bit-oriented面向位SYNC同步字符HDLC面向位的方案SDLC面向位的方案bit-stuffing位插入STP屏蔽双绞线UTP非屏蔽双绞线RG-58A/U标准RG-11用于10BASE5RG-59U75欧0.25INCH CATVRG-62U9欧0.25INCH ARCnet10BASE5IEEE802.3RG-59U0.25inch CATVRG-62U0.25inch ARCnetLED(light emitting diobe) 发光二级管ILD(injection laster diobe) 注入型激光二级管PIN检波器APD检波器intensity modulation亮度调制line of sight可视通路CCITT V.28(EIA RS232C)非平衡型CCITT V.10/X.26(EIA RS423A)新的非平衡型CCITT V.11/X.27(EIA RS422A)新的平衡型TD发送数据RD接收数据XON/XOFF流控制Automatic Repeat Request Protocol自动重发请求Send and wait ARQ:continuous ARQ停等ARQWard Christensen人名Kermit协议circuit switching线路交换packet switching分组交换virtual circuit虚电路ATM(asynchronous transfer mode) 异步传输模式异步时分多路复用packetizer打包器VPI(vritual path identifier)虚路径标识VCI(virtual channel identifier)虚通道标识syntax语法semantics语义timing定时OSI(open system interconnection)session会话synchronization同步activity management活动管理AE应用实体UE用户元素CASE公共应用服务元素SASE特定应用服务元素VT虚拟终端JIM作业传送和操作reverved保留echo回送discard丢弃active users活动用户daytime白天netstat(who is up of NETSTAT)qotd(quote of the day)日期引用chargen(character generator)字符发送器nameserver(domani name server)域名服务器bootps(bootstrap protocol server/client) 引导协议服务器/客户机tftp(trivial file transfer)简单文件传送sunrpc(sun microsystems RPC)SUN公司NTP:network time protocol网络时间协议SNMP(SNMP net monitor)SNMP网络监控器SNMP traps陷井biffunix comsat daemone.g timed daemon syslogsystem logURG紧急字段可用ACK确认字段可用PSH请求急迫操作连接复位SYN同步序号FIN发送方字节流结束Manchester曼彻斯特编码FDDI(fiber distributed data interface) 光纤分布数据接口TTRT目标标记循环时间aggregation of multiple link segments 多重链接分段聚合协议MAN(metropolitan area network plus)CSMA/CD(carrier sense multiple access/collision detection) 载波监听Token bus令牌总线Token ring令牌环SAP服务访问点request indictaion response confirmationLLC PDULLC协议数据单元DSAP address目地服务访问点地址字段SSAP address源服务访问点地址字段XID交换标识SABME置扩充的异步平衡方式DISC断开连接DM断开FRMR帧拒收solt time时间片AUI连接单元接口MAU介质连接接口MDI介质相关接口PMA物理介质接口SFD起始定界符PAD填充字段FCS帧校验序列PLS物理层收发信号slot timeInter Frame Gap帧attempt limit最大重传次数back off limit避免算法参数Jam size阻塞参数max frame size最大帧address size地址collaspsed backone 折叠式主干网基本服务集ESS扩展服务集DFW-MAC分布式基础无线MAC IFS帧间空隙SIFS:短PIFS点协调DIFS分布协调CTS发送清除DQDB(IEEE802.6)分布式队列双总线TDM时分复用TMS多时分交换TSI时间片互换TST网络机构TSSST STS SSTSS TSTST网络机构PSTN公用交换电话网public switched telephone network详细PBX:private branch exchange专用交换网PABX;private automatic branch exchange 自动交换机CBX:computerized branch exchange程控交换SLIP:serial line IP串行IPLCP(link control protocol)链路控制协议NCP:network control protocol网络控制协议BRI基本速率接口PRI群速率接口LAPB:line access protocol balanced链路访问协议平衡registration登录interrupt中断LAP F link access procedure for frame-mode bearer serives 太长了rotate不知道recovery恢复discard丢弃retransmission重传switched access交换访问intergated access集成访问alerting警告progress进展AALATM适配层GFCcell rate decoupling信元率去耦SDH同步数字级PDH准国步数字级GSM:group special mobile 移动通讯NSS网络子系统OMC-R操作维护中心BSS基站子系统基站控制器BTS基站收发信机MS移动站SIM:subscriber identity module标识模块MSC移动交换机HLR归属位置寄存器VLR访问位置寄存器AUC鉴权中心EIR设备识别寄存器OMC-S操作维护中心SC短消息中心WAP无线应用协议WAE无线应用层WSP会话层WTP事务层WTLS安全层WDP传输层MAP移动应用部分WML无线标记语言SSL:secure sockets layer安全套接层PCS个人通信业务PCN个人通信网GEO对地静止轨道NON-GE0(MEO,LEO)不清楚ITU国际电信联盟VSAT:very small aperture -terminal 甚小天线终端LEOS低轨道卫星通信系统repeater中继器bridge网桥router路由器gatewayONsemble stackable 10BASE 可叠加组合型集线器transparent bridge传输桥source routing bridge源路径桥broadcast storm广播风暴encapsulation封装translation bridging转换桥接方式SRT源地址选择透明桥偏移more flag标识ICMPINTERNET控制报文协议SPF:shortest path first最短路径IGP:interior gateway protocol核心网关协议EGP:exterior gateway protocol扩展网关协议RIP:routing information protocol路由信息协议OSPF开放最短径优先协议acquisition request获取请求acquisition confirm获取确认cease中止poll轮询IPX/SPX internetwork packet exchange/sequented packet exchange NOVELLinterpreter解释器redirector重定向器SFT system fault tolerant系统容错ELS entry level solution不认识ODI开放数据链路接口NDIS network device interface specification 网络设备接口...DDCS数据库管理和分布数据库连接服务DCE:distributed computing environment 分布计算环境OSF:open software foundation开放软件基金PWS:peer web serviceWEB服务器OEM原始设备制造商RAS远程访问服务IIS:Internet Information serverINTERNET信息服务WINS:windows internet name system WINDOWS命名服务NTDS:windows NT directory serverNT目录服务TDI传输驱动程序接口schedule++应用程序,预约本COSE:common open software environment 普通开放软件环境RPC远程过程调用SNMP:simple network management protocol 简单网管协议SMI:structer of management information管理信息结构SMT:station management管理站SMTP:simple mail transfer protocol简单邮件传输协议SNA:system network architectureIBM网络SNR:signal noise ratio信噪比SONENT:synchronous optical network 同步光纤网络SPE:synchronous payload envelope 同步PAYLOAD信CMIS/CMIP公共管理信息服务/协议CMISE公共管理信息服务agent代理IMT:inductive modeling technology不知道plaintext明文ciphertext脱密encryption加密decryption解密symmetric key cryptography 对称加密asymmetric key cryptography 不对称加密public key公钥private key私钥DES:data encryption standard数据加密标准IDEA:international data encryption algorithm 国际加密算法PIN:personal identification number个人标识符session key会话层密钥KDC:key distribuetion center密钥分发中心sign签名seal封装certificate证书certificate authority CA证书权威机构OSF开放软件中心AFS:andrew file system分布式文件系统ticket凭证authenticatior身份认证timestamp时间标记reply attack检测重放攻击realm域PKI公钥基础设施certificate hierarchy证书层次结构across certificate交叉证书security domain安全领域cerfificate revoke list(CRL)证书层次结构LDAP:light weight directory access protocol 协议access matrix访问矩阵ACL:access control list 访问列表reference monitor引用监控器course grained粗粒度访问控制medium grained中粒度访问控制fine grained细粒度访问控制CORBA面向对象的分布系统应用MQ报文队列VPN虚拟专网IPSEC:IP security安全IPSA:security association安全??encopulation security payload 封装安全负载AH:authentication header鉴别报头IKE:Internet key exchange交换rogue programs捣乱程序IPSP:IP security protocol安全IKMP:internet key managemetn protocol 协议IESGInternet工程领导小组SHA安全散列算法MAC:message authentication code代码CBC密码块链接SSL安全套接层协议cerfificate verify证书检验报文PEM私用强化邮件PGP:pretty good privacy 好的private保密authenticated已认证SEPP安全电子付费协议SET安全电子交易middleware中间件GSS-API通用安全服务SNP安全网络编程BWD:browser web database浏览WEBplugin插入件basic authentication scheme不知道digest authentication scheme摘要认证方法open group:the open group research institute 研究所DCE:distributed computing environment分布式计算机环境SLP:secure local proxy安全局部代理SDG:secure domain proxy安全域代理OMG:object management group目标管理组CORBS:common object request broker architecture 不清楚authentication鉴别access control访问控制data confidnetiality保密data integrity数据完整性non-reputation防止否认enciphermant加密机制digital signature mechanisms数据完整性authentication mechanisms路由控制机制notarization mechanisms公证trusted function可信security labels安全标记event dectection事件检测security audit trail安全审计跟踪security recovery安全恢复TCSEC:trusted computer system evaluation criteria标准TCSEC TNI:trusted network interpretation of the TCSEC 标准TCSEC TDI:trusted database interpretation of the TCSEC 标准ITSEC:information technology security evaluation。
应用层(Application Layer)与其他计算机进行通讯的一个应用,它是对应应用程序的通信服务的。
例如,一个没有通信功能的字处理程序就不能执行通信的代码,从事字处理工作的程序员也不关心OSI的第7层。
但是,如果添加了一个传输文件的选项,那么字处理器的程序员就需要实现OSI的第7层。
示例:telnet,HTTP,FTP,NFS,SMTP等。
表示层(Presentation Layer)这一层的主要功能是定义数据格式及加密。
例如,FTP允许你选择以二进制或ASCII格式传输。
如果选择二进制,那么发送方和接收方不改变文件的内容。
如果选择ASCII格式,发送方将把文本从发送方的字符集转换成标准的ASCII后发送数据。
在接收方将标准的ASCII 转换成接收方计算机的字符集。
示例:加密,ASCII等。
会话层(Session Layer)他定义了如何开始、控制和结束一个会话,包括对多个双向消息的控制和管理,以便在只完成连续消息的一部分时可以通知应用,从而使表示层看到的数据是连续的,在某些情况下,如果表示层收到了所有的数据,则用数据代表表示层。
示例:RPC,SQL等。
传输层(Transport Layer)这层的功能包括是否选择差错恢复协议还是无差错恢复协议,及在同一主机上对不同应用的数据流的输入进行复用,还包括对收到的顺序不对的数据包的重新排序功能。
示例:TCP,UDP,SPX。
网络层(Network Layer)这层对端到端的包传输进行定义,他定义了能够标识所有结点的逻辑地址,还定义了路由实现的方式和学习的方式。
为了适应最大传输单元长度小于包长度的传输介质,网络层还定义了如何将一个包分解成更小的包的分段方法。
示例:IP,IPX等。
数据链路层(Data Link Layer)他定义了在单个链路上如何传输数据。
这些协议与被讨论的各种介质有关。
示例:ATM,FDDI等。
物理层(Physical Layer)OSI的物理层规范是有关传输介质的特性标准,这些规范通常也参考了其他组织制定的标准。
Transmission Protocol: An Essential Component of Networking In the world of computer networks, the efficient and reliable transfer of data is essential. This is where transmission protocols come into play. Transmission protocols are sets of rules and procedures that govern how data is transferred between devices over a network. In this document, we will explore the significance of transmission protocols in networking, their types, and their role in ensuring smooth and error-free data transmission.Introduction to Transmission ProtocolsTransmission protocols are fundamental to the functioning of any computer network. They define the format, structure, and order in which information is sent across networks, ensuring that the data reaches its intended destination accurately.Transmission protocols work at the transport layer of the network protocol stack. They provide a means for devices to establish a connection, send data, verify its integrity, and ultimately terminate the connection. These protocols define the rules and mechanisms for error detection, correction, flow control, and congestion avoidance.Types of Transmission ProtocolsThere are several transmission protocols commonly used in computer networks. Let’s explore some of the most widely known ones:1. Transmission Control Protocol (TCP)TCP is one of the most common and widely used transmission protocols. It guarantees the reliable and ordered delivery of data between devices over an IP network. TCP uses a three-way handshake to establish a connection before data transmission begins. It provides congestion control, error detection, and retransmission of lost packets. TCP is ideal for applications that require data integrity, such as web browsing, file transfer, and email.2. User Datagram Protocol (UDP)Unlike TCP, UDP is a connectionless transmission protocol. It is faster but less reliable than TCP, as it does not ensure the ordered delivery or error recovery. UDP is often used for applications that prioritize speed and real-time communication, such as streaming media, online gaming, and VoIP (Voice over IP).3. Internet Protocol (IP)IP is not primarily a transmission protocol but rather a network-layer protocol in the TCP/IP protocol suite. It is responsible for routing packets of data acrossnetworks. IP handles the addressing and routing of data, while transmission protocols like TCP and UDP handle the reliable transfer of the data packets.4. File Transfer Protocol (FTP)FTP is a file transfer protocol used for transferring files between a client and a server over a network. It operates on top of the TCP protocol, ensuring reliable and secure file transfers. FTP allows users to upload, download, and manage files on remote servers.There are, of course, many other transmission protocols in use today, each serving specific needs and requirements within the networking domain.The Role of Transmission ProtocolsTransmission protocols play a crucial role in networking by enabling the seamless transfer of data between devices. Some of the key roles of transmission protocols are:1. ReliabilityReliability is a cornerstone of transmission protocols. Protocols like TCP ensure that data packets are delivered accurately and in the correct order. They provide error detection and correction mechanisms, guaranteeing data integrity during transmission. This reliability is paramount for critical applications, where data loss or corruption is unacceptable.2. Flow ControlFlow control ensures that data is sent at a pace the receiving device can handle. Transmission protocols employ flow control mechanisms to prevent overwhelming the recipient with a flood of data. By negotiating the transmission speed and buffering capability, flow control mechanisms prevent congestion and enhance the overall efficiency of data transfer.3. Congestion ControlCongestion control is crucial to avoid network congestion, where the network becomes overloaded with excessive data traffic, leading to packet loss and degraded performance. Transmission protocols implement congestion control algorithms to monitor network conditions and adjust transmission rates accordingly. This prevents network congestion and ensures fair utilization of network resources.4. Disconnection and TerminationTransmission protocols provide mechanisms for the proper termination of a connection. They enable devices to gracefully close the connection and releaseallocated resources. This ensures efficient network resource utilization and avoids unnecessary overhead.5. CompatibilityTransmission protocols are designed to be interoperable across different network devices and platforms. This compatibility allows devices and systems from various vendors to communicate with each other seamlessly, regardless of the underlying hardware or software differences.ConclusionTransmission protocols are vital components of computer networks, facilitating the efficient and reliable transfer of data. They ensure data integrity, enable flow and congestion control, and provide mechanisms for proper connection establishment and termination. Understanding the role transmission protocols play in networking is essential for network administrators and professionals alike.。
网络术语中英对照1. ADSL Asymmetric Digital Subscriber Line 非对称数字环路2. ANSI American National Standard Institute 美国国家标准协会3. APIPA Automatic Private IP Addressing 自动私有IP寻址4. AppleTalk 由Apple公司推出的一种多层协议,一种可路由协议组5. ARP Address Resolution Protocol 地址解析协议6. ARQ Automatic Repeat Request 自动重发请求7. ASIC Specific Integrated CircuitChip 专用集成电路芯片8. Abstract Syntax Notation One 一种用于描述结构化客体的结构和内容的语言. 抽象语法定义9. ATM Asynchronous Transfer Mode 异步传输模式10. BBS Bulletin Board System 电子公告板11. BGP Border Gateway Protocol 边界网关协议12. B-ISDN Broadband Integrated Services Digital Network 宽带综合业务数字网13. BOOTP BOOTstrapping Protocol 引导协议14. BRI Basic Rate Interface ISDN基本速率15. Bridge 网桥16. BUS Broadcast/Unknown Server 广播和未知服务器17. CA Communication Automatization 通信自动化18. Cable Modem 电缆调制解调器19. CATV 公用天线电视20. CCITT 国际电话电报咨询委员会21. CD Campus Distrbutor 建筑群配线设备22. CDMA Code Division Multiple Access 码分多址23. CDPD Cellular Digital Packet Data 蜂窝数字分组数据24. CERNET 中国教育科研网25. CMIS/CMIP Common Management Information Service/Protocol 公共管理信息服务/协议26. CORBA Common Object Request Broker Architecture 公共对象请求代理结构27. CP Consolidation Point 集合点28. CRC Cyclic Redundancy Checks 循环冗余码校验29. CSMA/CD Carrier Sense Multi-Access/Collision Detection 载波侦听多路访问/冲突检测30. DARPA Defense Advanced Research Projects 国防部高级计划署31. DCE Digital Circuit-terminating Equipment 数据电路端接设备32. DHCP Dynamic Host Configuration Protocol 动态主机配置协议33. DNS Domain Name System 域名系统34. DPI Dot Per Inch 每英寸可打印的点数35. DSL Digital Subscriber Line 数字用户线路36. DTE Data Terminal Equipment 数据终端设备37. EGP Exterior Gateway Protocol 外部网关协议38. EIA/TIA Electronic Industries Association and the Telecommunication Industries Association 电子工业协会/电信工业协会39. E-mail Electronic Mail 电子邮件40. ER Equipment Room 设备间41. FAQ Frequently Answer Question 常见问题解答42. FC Fiber Channel 光纤信道43. FD Floor Distributor 楼层配线设备44. FDDI Fiber Distributed Data Interface 光纤分布式数据接口45. FDM Frequency Division Multiplexing 频分多路复用46. FEC Forward Error Correction 前向差错纠正47. FR Frame Relay 帧中继48. FTP File Transfer Protocol,Foil Twisted Pair 文件传输协议,金属箔对绞线49. FTTB Fiber To The Building 光纤到大楼50. FTTC Fiber To The Curb 光纤到楼群51. FTTD Fiber To The Desk 光纤到桌面52. FTTH Fiber To The Home 光纤到户53. FTTH Fiber To The Home 光纤到家庭54. Gateway 网关55. GCS Generic Cabling System 综合布线系统56. GSM Global Systems for Mobile communications 移动通信全球系统全球通57. HDLC High-Level Data Link Control 高级数据链路控制协议58. HDTV High Definition TeleVision 数字高清晰度电视59. HFC Hybrid Fiber Coax 混合光纤同轴60. hop 跳数61. hostname 主机名62. HTTP HyperText Transfer Protocol 超文本传输协议63. Hub 集线器64. IAB Internet Architecture Board 因特网结构委员会65. IANA Internet分配数据机构66. IAP Internet Access Provider 因特网接入提供商67. IBS Intelligent Building System 智能大楼系统68. ICCB Internet Control and Configuration Board Internet控制与配置委员会69. ICMP Internet Control Message Protocol 因特网控制报文协议70. ICP Internet Content Provider Internet 内容提供者71. IDC Insulation Displacement Connection 绝缘压穿连接72. IDF Intermediate Distribution Facility 分配线架73. IDU Interface Data Unit 接口数据单元74. IEEE Institute of Electrical and Electronics Engineers 电子和电气工程师协会75. IETF Internet Engineering Task Forc 因特网工程任务组76. IGMP Internet Group Management Protocol Internet组管理协议77. IGP Interior Gateway Protocol 内部网关协议78. IISP 间歇交换机信令协议79. IMP Interface Message Processor 接口信息处理机80. IMTS Emproved Mobile Telephone System 改进型移动电话系统81. IP Internet Protocol 网际协议82. IPsec Internet协议安全83. IPX/SPX Netware 的网际数据包交换/系列数据包交换84. IrDA 红外线数据协议85. IRQ 中断请求号86. ISDN Integrated Services Digital Network 综合业务数字网87. ISO International Organization for Standardization 国际标准化组织88. ISP Internet Service Proveder 因特网服务提供商89. IT Information Technology 信息技术90. ITSEC 信息技术安全评价标准91. ITU International Telecommunications Union 国际电信联盟92. JPEG Joint Photographic Experts Group 图像专家联合小组93. LAN Local Area Network 局域网94. LANE LAN Emulation 局域网仿真95. LAP Link Access Procedure 链路访问过程96. LCP Link Control Protocol 链路控制协议97. LE_ARP LAN仿真地址转换协议98. LEC LAN Emulation Client 局域网仿真客户端99. LECS LAN Emulation Configure Service 局域网仿真配置服务100. LED 发光二极管101. LES LAN Emulation Server 局域网仿真服务器102. LLC Logical Link Control 逻辑链路控制103. MAC Media Access Control 介质访问控制104. MAN Metropolitan Area Network 城域网105. MAU Medium Access Unit 介质访问单元106. MDF Main Distribution Facility 主配线架107. MIB Management Information Base 管理信息库108. Modem 调制解调器109. MPC Client MPOA110. MPEG Motion Picture Experts Group 活动图像专家组111. MTBF Media Time Between Faults 两次故障间的平均时间112. MTOR Media Time of Repair 故障修复所需平均时间113. MTTD Media Time to Diagnose 故障诊断所需平均时间114. MTU Maximum Transfer Unit 最大传输单元115. NAP Network Access Point 网络接入点116. NAT Network Address Translation 网络地址翻译器117. NCP Network Control Protocol Novell NetWare核心协议,网络控制协议118. NCSA 国家计算机安全协会119. NetBEUI NetBIOS增强型用户接口120. netmask 网络掩码121. NEXT 近端串扰122. NFS Network File System 网络文件系统123. NIC Network Information Center,Network Interface Card 网络信息中心,网卡124. N-ISDN Narrowband Integrited Services Digital Network 窄带ISDN125. NSAP Network Service Access Point 网络服务接入点126. NSF 美国国会科学基金会127. NVT Network Virtual Terminal 网络虚拟终端128. OA Office Automatization 办公自动化129. ODBC Open Database Connection 开放数据库互连130. ORB Object REquest Broker 对象请求代理131. OSF Open Software Fundation 开放软件基金会132. OSI Open System Interconnection 开放系统互联133. OSPF Open Shortest Path First 开放最短路径优先协议134. pack 分组135. Packet switching 分组交换136. PAD packet Assembler Dissmbler 分组装拆器137. PBX Private Branch eXchange 用户电话交换机138. PCM Pulse Code Modulation 脉冲编码调制139. PDA Personal Digital Assistant 个人数字助理140. PDN Public Data Network 公用数据网141. PDS Premises Distribution System 建筑物布线系统142. PDU Protocol Data Unit 协议数据单元143. PKI 公用密钥基础结构144. PON 无源光纤网145. Port 端口146. PPP Point to Point Protocol 点到点协议147. PPTP 点到点隧道协议148. PRI Primary Rate Interface ISDN基群速率接口149. PRN Packet Radio Network 分组无线网150. PSTN Public Switched Telephone Network 公用电话交换网151. PVC Permanent Virtual Circuit 永久虚电路包括PVPC和PVCC 152. PVCC permanent virtual channel connection 永久虚通道连接153. PVPC permanent virtual path connection 永久虚通路连接154. QoS Quality of Service 服务质量155. RARP Reverse A ddress Resolution Protlcol 反向地址解释协议156. RAS 远程访问服务器157. repeater 中继器158. RFC Request for Comments 请求评注159. RIP Routing Information Protocol 选路信息协议160. Router 路由器161. RPC Remote Procedure Call 远程过程调用162. SAP Service Access Point 业务接入点163. SCS Structured Cabling System 结构化布线系统164. SDH Synchronous Digital Hierarchy 同步数字系列165. SDLC Advanced Data Communication Control Procedure 同步数据链路控制协议166. SFTP Shielded Foil Twisted Pair 屏蔽金属箔对绞线167. SLIP Serial Line Interface Protocol 串行线路IP168. SMTP Simple Mail Transfer Protocol 简单邮件传输协议169. SNA System Network Architecture 系统网络体系结构170. SNMP Simple Network Management Protocol 简单网络管理协议171. SNR Signal-Noise ratio 信噪比172. SONET Synchronous Optical Network 同步光纤网络173. STP Shielded Twisted Pair 屏蔽双绞线174. subnet 子网175. subnet mask 子网掩码176. SVC Switched Virtual Circuit 交换虚电路177. Switch 交换机178. TC Transmission Convergence 传输汇集子层179. TCP Transmission Control Protocol 传输控制协议180. TCP/IP 传输控制协议/网际协议181. TDM Time Division Multiplexing 时分多路复用182. TFTP Trivial File Transfer protocol 单纯文件传输协议183. thick 粗缆184. thin 细缆185. TLS 传输层安全186. TO Telecommunications Outlet 信息插座电信引出端187. TP Transition Point 转接点188. TTL Time To Live 生存时间189. UDP User Datagram Protocol 用户数据报协议190. URL Universal Resource Locator 统一资源定位191. USB Universal Serial Bus 通用串行总线192. UTP Unshielded Twisted Pair 非屏蔽双绞线193. VLAN Virtual LAN 虚拟LAN194. VOD Video on Demand 点播图像195. VRML Virtual Reality Modeling Language 虚拟现实造型语言196. VTP 虚拟隧道协议197. WAN Wide Area Network 广域网198. WDM Wavelength Division Multiplexing 波分多路复用199. WINS Windows Internet名称服务200. World Wide Web 万维网。
VITP:An Information Transfer Protocol for VehicularComputing∗Marios D.Dikaiakos †Dept.of Computer Science University of Cyprus Nicosia,CY1678,Cyprus mdd@ucy.ac.cySaif IqbalDept.of Computer Science Rutgers University Piscataway,NJ08854,USA saiqbal@T amer Nadeem ‡Dept.of Computer Science University of Maryland College Park,MD,USA nadeem@Liviu Iftode Dept.of Computer Science Rutgers University Piscataway,NJ08854,USA iftode@ABSTRACTRecent advances in wireless inter-vehicle communication sys-tems enable the development of Vehicular Ad-Hoc Networks (V ANET)and create significant opportunities for the de-ployment of a wide variety of vehicular applications and ser-vices.In this paper,we introduce the Vehicular Information Transfer Protocol(VITP),an application-layer communica-tion protocol,which is designed to support the establishment of a distributed,ad-hoc service infrastructure over V ANET. The VITP infrastructure can be used to provide location-based,traffic-oriented services to drivers,using information retrieved from vehicular sensors and taking advantage of on-board GPS navigation systems.In this paper,we present the key design concepts of the protocol and the infrastruc-ture,the protocol specification,simple examples of protocol interactions that support driver inquiries,and a simulation study of VITP performance properties.Categories and Subject Descriptors:C.2,C.2.2 General Terms:Design,PerformanceKeywords:Vehicular Computing,Location-based Services, Middlewareand price-lists of gas stations,location and menus of restau-rants).This information can be fused with GPS navigation information,extending the functionality of state-of-the-art, on-board navigation systems.For the deployment and provision of vehicular services, we propose the development and deployment of an ad-hoc service infrastructure on top of emerging vehicular ad-hoc networks(V ANETs).We introduce the Vehicular Informa-tion Transfer Protocol(VITP),an application-layer commu-nication protocol specifying the syntax and the semantics of messages between VITP peers,i.e.the software components of our proposed service infrastructure.A VITP peer runs on the computing device of a vehicle,uses its IVC capa-bilities,and accesses the vehicle’s sensors to retrieve use-ful information.VITP peers establish on-demand dynamic, ad-hoc groups,which collect,communicate,and combine information from the on-board sensors of different vehicles in order to resolve incoming requests.VITP is inspired by the HyperText Transfer Protocol of the World-Wide Web. However,it differs from HTTP in several fundamental as-pects,such as:(i)the semantics of VITP-peer interaction vs.the HTTP request-reply exchange;(ii)the functionality and the role of VITP software components vs.the clients and servers in HTTP,and(iii)the support for push-based communication in VITP.These differences are mainly due to the ad-hoc,dynamic,and unreliable nature of vehicular ad-hoc networks,and the need to deploy VITP services even on top of embedded computers with limited resources.The remaining of this paper is organized as follows.In Section2,we present a motivating scenario,introduce the VITP service model and present the key design concepts of VITP.In Section3,we give a brief overview of the VITP specification.Section4,presents a simulation study which uses a vehicular traffic generator for investigating key perfor-mance metrics of VITP in a realistic scenario.We conclude in Section5.2.A SERVICE MODEL FOR V ANETS2.1ContextTo describe the infrastructure required for providing ve-hicular services and to present the VITP design,we intro-duce a simple motivating scenario taking place in the city setting of Figure1.This Figure represents the plan of a small city-district,which is traversed byfive streets;the direction of traffic is depicted with arrows placed near the street names.A snapshot of traffic conditions is superim-posed on the plan.This snapshot depicts a number of ve-hicles(shown as grey boxes)of various sizes located on the district streets.We assume that most vehicles are equipped with an em-bedded computer with a display interface,a GPS receiver, a wireless network interface for inter-vehicle communication (compliant to standards like802.11x or DSRC)[12],and an on-board diagnostics(OBD)interface.Some vehicles may have alternative wireless network connectivity support thanks to an on-board cellular GSM/GPRS device.The OBD can be used to acquire a small set of data values from mechanical and electronic sensors mounted on the vehicle (e.g.,current speed and acceleration,direction of motion, average speed during the last few minutes).We assume that all subsystems(GPS,OBD,wireless networking)are connected and provide data to the embedded computer.WeFigure1:A vehicular service provision scenario. also assume that a navigation software system is installed on the computer and enables the association of the vehicle’s ge-ographic position to an internal data-structure representing the road networks of a large geographic area around the ve-hicle.Such a data structure can be easily constructed from publicly available geographic referencing systems[3].The feasibility of such vehicular systems has been demonstrated in a number of recent projects[5,15]).The vehicles establish a vehicular ad-hoc network(V ANET) infrastructure through their wireless connections;Figure1 depicts V ANET connections as dashed,double-headed ar-rows connecting vehicles.A number of roadside service facilities(gas stations,coffee shops,restaurants)are also equipped with short-range wireless interfaces and partici-pate in the V ANET infrastructure.Vehicles and roadside stations use this infrastructure to exchange messages.Multi-hop message delivery can be supported by geographic rout-ing protocols,which push messages toward their geographic destination[6,8,9,10,11].In the absence of a V ANET infrastructure,messages can be transported to their desti-nation area through alternative wireless(cellular/GPRS)or wireline networks(Internet),and then passed onto moving vehicles via roadside wireless gateway stations.The details of message routing are outside the scope of this paper.2.2Motivation and Problem StatementThe types of services that we wish to support are illus-trated with the following example:We assume that vehicle A,located at the top right of Figure1and moving southward on Woods Ave,is heading to a destination on the West side of the city.The driver wants to go either through Rt513 or through27th Str.She is also interested in getting gas along the way,but is not willing to pay over1.8dollars per gallon for gasoline.The driver asks the on-board navigation system for the traffic conditions on alternative routes that lead to Rt513West and27th Str West,and for the location of drive-in coffee shops and gas stations along those routes. Notably,a possible way to Rt513goes through JFK Dr, which is only a few meters down the road from the present location of A.Therefore,the service infrastructure should try to come up with a reply to the driver’s requests,well before the driver decides whether or not to take the JFK Drexit.The interaction between the driver and the on-board navigation system can be performed either with a voice or with a simple touch-screen interface.The information requested by the driver of vehicle A can be computed out of data available on vehicles and roadside facilities located in the road segments specified by A’s in-quiries.For instance,the traffic-flow on the segment of Rt513shown in Figure1can be derived by estimating the average speed of vehicles moving on that segment for a short period of time;a congestion in that road segment can be es-tablished from a consistently low average speed and/or a high density of vehicles on that road.Similarly,the op-eration of a gas station on27th Str can be deduced from information dispatched by the gas-station’s wireless access point,which specifies the type of service offered(selling gas), the business address,and gas prices.To retrieve that information,the on-board system of ve-hicle A has to translate end-user inquiries into a sequence of location-sensitive queries.Each of these queries should be routed toward its designated location of interest,either via the vehicular ad-hoc network or through some other avail-able network.Upon arrival to its destination area,the query must be picked up by the local vehicular service infrastruc-ture.Nodes of that infrastructure(vehicles and/or roadside services)collaborate on-the-fly to compute a reply,which is dispatched back to the location where the query came from. The goal of our work is to take advantage of V ANETs established among vehicles equipped with the capabilities described in section2.1,in order to design a vehicular ser-vice infrastructure that is capable of carrying out transac-tions like the ones described above.As key building blocks of this infrastructure,we introduce:(i)The Vehicular In-formation Transfer Protocol.VITP is an application-layer,stateless communication protocol,which specifies the syntax and the semantics of messages carrying location-sensitive queries and replies between the nodes of a ve-hicular ad-hoc network.VITP is independent of underly-ing V ANET protocols that undertake the transmission and routing of VITP messages.(ii)The VITP peer,which is a lightweight software component to be deployed on the embedded computer of modern vehicles.VITP peers imple-ment the VITP protocol and operate as clients,intermedi-aries,or servers in a VITP-protocol interaction.(iii)A lo-cation encoding scheme,which organizes and represents symbolically road segments and directions.This scheme is used by VITP for the specification of location-aware queries and for supporting underlying geographic routing protocols, which make use of on-board navigation services to transform symbolic locations into GPS coordinates[14,5].(iv)A num-ber of protocol features designed to support performance optimizations(message caching,VITP traffic reduction), quality assurance for VITP results(termination condi-tions of VITP queries),and the protection of privacy of vehicle drivers.In contrast to recent traffic monitoring systems,which are based on the continuous dissemination of traffic conditions through vehicular ad-hoc networks[14],VITP proposes the pull-based retrieval of traffic information,which can be trig-gered on-demand by location-sensitive queries issued from VITP-enabled vehicles.VITP supports also the push-based propagation of messages,as a mechanism for disseminating various alerts that carry information about emergencies or serious deviations from normal traffic conditions.2.3Key Design ConceptsWe anticipate that service provision over vehicular ad-hoc networks will be based on an extended client-server com-puting model.In this model,a driver inquires information about traffic conditions or available facilities on some road segment.This inquiry is translated into query messages sent toward that road segment,via the underlying V ANET.Vehi-cles in the destination area collaborate to establish a server, to resolve the incoming queries and to send back messages carrying the requested information.The Vehicular Informa-tion Transfer Protocol specifies the format and the semantics of query and reply messages exchanged between vehicular clients and servers.For the design of the VITP architec-ture and message specification we must take into account the following key observations:2.3.1Location-aware requestsIn a vehicular-service provision model,service requesters are interested primarily in attributes describing traffic con-ditions and service facilities available to drivers in some par-ticular geographic area.Therefore,vehicular-service queries must be location-sensitive,specifying explicitly the target location of their inquiry.Given that the motion of vehicles is constrained within the road system,we can assume that the geographic areas of interest are restricted to roads,road segments,directions of traffic,and adjacent roadside areas. Accordingly,locations are represented in VITP as two-value tuples[road id],where roadid is a number repre-senting a segment of that road;opposite traffic directions on the same part of a road are represented as different road-segments.The[road id]representation of a vehicle’s location is used in GPS-based,driver-friendly nav-igation support systems.It can be derived from a vehicle’s GPS position(longitude,latitude)with a transformation calculation that uses information from public databases that store the correspondence of(longitude,latitude)posi-tions to road id tuples[3].The feasibility of such transformations has been demonstrated in recent liter-ature[15,5].2.3.2Virtual Ad-Hoc Servers(VAHS)Because of the extensive size of road networks and the dy-namic nature of traffic-related information,centralized ap-proaches for vehicular-service information provision can be very hard and prohibitively expensive to implement.The collection,indexing,continuous update,and timely publica-tion of traffic-related information through centralized servers requires:(i)an extensive infrastructure of sensors that con-tinuously monitor traffic and service conditions,collecting information even in the absence of information consumers and queries;(ii)the management of a high volume of mes-sages carrying updates to central servers on a continuous ba-sis;(iii)a highly efficient server infrastructure that can pro-cess numerous simultaneous updates throughout large geo-graphic areas and can provide timely and accurate replies to queries;(iv)a communication infrastructure that can carry large volumes of service queries and replies between mov-ing vehicles and central servers,and(v)a costly effort to maintain the monitoring and communication infrastructure in good running condition.Consequently,it is questionable whether a centralized approach would scale to a wide geo-graphic area and to a large number of vehicles.Figure2:Clients and Servers in a VITP transaction. To address the scalability problems of centralized approaches, VITP relies on no additional infrastructure,besides the one assumed to be available on moving vehicles and roadside fa-cilities(see Section2.1).Consequently,the server that com-putes the reply to a VITP query is essentially a dynamic collection of VITP peers,each of which:(i)Runs on a vehi-cle that moves inside the query’s target-location area.(ii)Is willing and able to participate in the query’s resolution by contributing information from its on-board diagnostics sen-sors or local memory.The establishment of this collection of peers is done in an ad-hoc manner,and relies on the vehicu-lar ad-hoc network established by vehicles moving inside the target-location area.To better reflect the dynamic and ad-hoc establishment of VITP servers,we refer to the dynamic collection of VITP peers that are inside the target-locationof a VITP query and take part in the query’s resolution,asa Virtual Ad-Hoc Server(VAHS).It is important to note that the collection of peers that constitute a V AHS,and the VITP peers that manage the VITP communication,follow a best-effort approach in their operation.In other words,they provide no guarantees or special features for the recovery of lost or dropped mes-sages.It is also worth noting that a VITP peer,which has joined a Virtual Ad-Hoc Server,does not have infor-mation about other members of the group.It is also pos-sible that a VITP peer joins a V AHS,participates in its computation,and leaves the target-location area before the completion of the query’s resolution.The Virtual Ad-Hoc Server,on the other hand,does not maintain explicit knowl-edge of its members.The V AHS is established on-the-fly;its constituents can be derived only by the choice that VITP peers make individually about serving or simply forwarding VITP requests,and by the semantics of the VITP messages they exchange.In other words,the Virtual Ad-Hoc Server is identified with a query and its target-location area,rather than with the VITP peers that participate in it.In that perspective,the V AHS is similar to the SpatialViews system introduced in[16].We have taken this approach in order to make the VITP protocol stateless and lightweight,and to keep the VITP state-machines as simple as possible.This is necessary in order to design simple and efficient VITP peers that can easilyfit even on on-board embedded processors.2.3.3VITP transactionsFigure2depicts a typical VITP-transaction that takes place in the context of the service-provision scenario pre-sented earlier in Figure1.This transaction is initiated by vehicle A,which is located in road segment S(Woods Ave in Fig.1)and inquires information about the average speed of at least four vehicles inside road segment L(first seg-ment of Rt513),as an estimate of traffic-flow conditions in L.To this end,the VITP peer of A submits a VITP re-quest Q with A’s inquiry.We assume that the source and the target-location areas,S and L,are connected through a vehicular ad-hoc network as shown in Figure1.The VITP transaction consists of four phases.In the ini-tial dispatch-query phase,Q is transported through the un-derlying V ANET toward target area L.Q goes through a number of intermediary V ANET nodes,which push the mes-sage toward its destination using geographic routing.It is worth noting that intermediary nodes may not be VITP-enabled(these are depicted as grey pentagons in Figure2); these nodes simply pass the message on toward L.When Q is received by a peer B that is inside target-area L and is willing to join a Virtual Ad-Hoc Server to resolve Q,the VITP transaction enters its second phase, the VAHS-computation phase.During this phase,the VITP request is routed between the VITP peers of the V AHS. These peers modify the VITP request in order to:(i)indi-cate that the request is part of an ongoing V AHS computa-tion(this modification takes place only at thefirst peer that joins the V AHS),and(ii)piggyback partial query results to the VITP message’s payload.Referring,for example, to Figure2,when peer B receives the VITP request Q,it parses the request,extracts the requested information from its on-board diagnostics system,rewrites the query in order to store the partial result into the query’s body and to in-dicate that the query is now part of a V AHS computation, and passes the message on to its neighbor.The semantics of the query indicate how the underlying network protocol will treat the rewritten VITP query(unicasting or broadcasting it to neighboring peers).A VITP request is transported between V AHS peers until some Return Condition is satisfied.The V AHS peer that detects the upholding of the Return Condition,creates the VITP reply and posts it toward source-region S through the V ANET.The transportation of the VITP reply toward S corresponds to the third phase of the VITP transaction,the dispatch-reply phase.When the VITP reply reaches area S,the VITP transaction enters itsfinal phase,the reply-delivery phase.During this phase,the underlying network protocol broadcasts the VITP reply to the V ANET nodes of S,so that the reply can be received by the VITP peer of A. The case that a vehicle has moved outside its initial road segment by the time a VITP reply reaches that road seg-ment,can be dealt by the V AHS by specifying an extended region over which the reply should be broadcast.2.3.4Return ConditionsAn important issue arising in the context of the V AHS-computation phase is how to define the Return Condition for a VITP request.A Return Condition determines at which point the resolution of a VITP request can be considered done.In other words,the Return Condition indicates if a VITP reply can be created and dispatched back to the originator of the request.The decision on what constitutessuccess in the resolution of a VITP query,however,depends on the semantics of the query itself.Therefore,the Return Condition must be defined explicitly as part of the query’s specification.For instance,referring to our example of Figure2,sup-pose that vehicle A is looking for a gas station on road seg-ment L;when the corresponding VITP request reaches the VITP peer of gas station G,the peer switches to the V AHS-computation phase,parses the incoming query,detects that the query requests information about at least one gas sta-tion in L,and decides that it can fully resolve the query and that the Return Condition is satisfied.Consequently,it cre-ates a VITP-reply message with G’s coordinates and prices, and sends the reply to S.In contrast,if A is looking for the prices of more than one gas stations in road segment L,G’s peer will start the V AHS-computation phase,re-write the incoming query,and try to pass the query on through the V ANET,in search of other gas stations:clearly,the query’s Return Condition is not satisfied yet.In the absence of other gas stations in L,however,this Return Condition will never be met,the original VITP query will not be resolved, and A’s peer will not receive any VITP reply.To address such cases,VITP supports an alternative Return Condition, which is constrained on the total time the infrastructure can spend in a V AHS-computation phase.2.3.5Protocol layeringThe operation of the VITP protocol presumes an underly-ing networking infrastructure,which undertakes the trans-port and routing of VITP messages between peers installed in vehicles and roadside services.Typically,networking sup-port will be provided by vehicular ad-hoc networks,although VITP messages could also be transported via other net-works,such as GSM/GPRS.It is important to observe that the way V ANET nodes handle VITP messages is influenced by VITP semantics.In particular,a VITP message that is part of a VITP transaction in either dispatch-query or dispatch-reply phase,must be routed geographically toward its target location.In contrast,a VITP reply that is part of a VITP transaction in the reply-delivery phase,should be broadcast inside its target-location area(and/or nearby areas),so that it reaches the VITP peer that originated the VITP transaction.Finally,the routing of a VITP mes-sage that is part of a V AHS-computation phase,depends on the semantics of the method specified in the corresponding VITP request.For example,in Figure2,the resolution of VITP query Q can be satisfied with a simple tour through the V AHS peers of road segment L.This can be achieved by unicasting Q inside L.A different request method,or a dif-ferent resolution method for the same request,may dictate the broadcasting of Q inside L.The interaction between VITP and the routing protocol of the underlying V ANET is as follows:whenever a VITP message arrives at a V ANET node,the network layer always makes a call to the local VITP peer(see Figure3).This call is made even if the peer is an intermediary,i.e.,it is not placed inside the target location of the message.If the node is not VITP-enabled or if its VITP peer is busy or down, the call will fail;in that case,the network layer will simply retransmit the message to a neighboring node.Otherwise, the peer will receive and parse the message.Depending on the active VITP phase and the semantics of the message,the peer may re-write the message before retransmission.TheFigure3:Protocol layering.peer will also signal the V ANET routing module about the routing method to be used when transmitting the outgoing message(unicast or broadcast).2.3.6Other IssuesCaching:In the scenario of Figure2,if the VITP peer is an intermediary and the incoming message is a request,the peer can search into its local cache for a matching reply.The matching test should take into account both the semantics of the VITP query(as described by the query’s uri)and the specification of the target region.In the case of a match, the peer can send the cached reply back to the VITP client and either complete the VITP transaction or retransmit the incoming message toward its target location.This decision affects the Return Condition of the VITP request and must be based on the semantics of the incoming VITP message. Therefore,VITP provides cache-control headers that can be included in VITP messages and act as directives to VITP-peer caching decisions.Message Identifiers:To achieve the delivery of a VITP reply to the peer that requested it and to preserve the cor-rectness of a V AHS computation,we must ensure that:(i)A VITP peer can match incoming replies against its pending requests and can detect replies belonging to other peers. (ii)A VITP peer will not act again on the same VITP re-quest even if it receives this request multiple times.To this end,a unique,random identifier(msgID)is attached to ev-ery new request.The same identifier is also attached to messages derived from the original VITP request,that is,to modified requests exchanged during a V AHS-computation phase and to the resulting VITP replies.VITP peers main-tain a cache with recently received msdID’s.Every time a peer receives a VITP message,it compares its msgID against cached msgID’s in order to determine how to handle the in-coming message.New identifiers are cached for a default period of time.Driver privacy:VITP message identifiers can be pro-duced by random-number generators minimizing the possi-bility of clashes(where two different VITP messages have the same identifier).It is worth noting that the use of a randomly produced,unique identifier for every new VITP request protects driver privacy,because the messages ex-changed in the context of a VITP transaction do not carry any information identifying the driver or the vehicle that initiated the transaction.VITP message syntaxnumber> Line2:Target:[rd id-dest]Line3:From:[rd id-src]with<speed> Line4:Time:<currenttime>Line6:Cache-Control:<directive>Line7:TTL:<time live>Line8:msgID:<uniqueURI syntaxexpr>,...]&<paramroad Table2:Type and query tag combinations. ties:vehicle and service.The service entity corresponds to roadside facilities that offer services to vehicles(gas sta-tions etc).Other entities could be easily supported,such as trafficexpr).These expressions are placed inside a pair of brackets immediately after the“?”character.There are two default return-condition pa-rameters,tout and cnt.tout(time-out)specifies the maximum lifetime of a GET-request resolution(V AHS-computation phase);cnt(count)specifies the number of peers that should contribute to the resolution of a request.Every VITP peer that receives a request and participates in its resolution reduces the cnt value by one.Then,the peer checks whether the value of cnt equals zero or if the timeout period has been exceeded.In such a case,the Return Condition of the request is satisfied and a reply can be produced and transmitted back to the VITP client that issued the request.2.Expressions placed after the Return Condition brack-ets.These,specify the values that are passed to the actual query that is to be executed on the VITP peer (<paramthat the query should go through all the reachable vehicles and retrieve their speed;the V AHS-computation phase must not take longer than1800msec.The following three requests specify respectively:(i)a query for any gas-station facilities with a price of not more than2dollars per gallon;(ii)a query for any posted alerts regarding traffic accidents;(iii)the generation of an alert regarding a slippery road condition. For the“slippery road”alert,which is a POST,the sender is not interested in getting back any information.The goal is rather to disseminate the information.Therefore there is no Return Condition specified and it is up to the recipients of the alert to cache and/or keep posting it for as long as they seefit.The VITP implementation can impose a default timeout Return Condition of several hours,if the toutfield of a query is set to“*.”The Target and From headers of Lines2and3in Table1 specify the target and source-location areas of a VITP mes-sage,respectively.Locations are formatted according to a standard scheme that specifies the road and segment identi-fiers,as retrieved by an on-board navigation and positioning system.In the case of GET messages,the source-location area can be followed by an optional entity specifying the speed of the vehicle at the time that the request is created.This information can be useful in case the V AHS needs to esti-mate the location of the source vehicle when routing a reply back to it.The Time header(Line4in Table1)carries a time-stamp specifying the point in time at which the VITP message was generated by its originating peer.The Expires header of a VITP message(Line5in Table1)specifies a point in time after which the corresponding VITP transaction has to be terminated.In the case of a GET request,the expiration time indicates that the originating peer wants to receive a reply before the specified expiration time.Consequently,any peer that receives a VITP message(request or reply)as part of the transaction after this time,can drop the message and not propagate it further.In the case of a POST request, the expiration-time header indicates when the VITP peers should stop propagating the corresponding alert.The Cache-control header of Line6defines the caching directives that should apply to a VITP request.In the case of GET messages,the possible values that can be assigned to this header are:(i)“no,”which indicates that the origina-tor peer does not accept as reply a message generated dur-ing a previous transaction and cached in the infrastructure; (ii)“yes,”which indicates that the originator peer is willing to accept a reply previously cached during some other trans-action,and(iii)“fwd,”which indicates that the peer wishes that the transaction goes forward but is also willing to ac-cept cached replies.The use of caching(Cache-control: yes)can result to VITP peers receiving replies faster and to an overall reduction of VITP messages exchanged,at the ex-pense of the accuracy and freshness of query results.In the case of POST messages,the Cache-Control header specifies whether the POST message is cacheable(value set to“yes”) or not(value set to“no”).If caching is allowed,the TTL header can be used to determine for how long a reply can be kept in intermediary caches.The msgID header is used to carry the unique numerical message identifier that is assigned to every VITP query.As mentioned in the previous section,and in order to protect driver privacy,instead of using as msgID the Vehicle Identi-fication Number(VIN)which is unique for every vehicle,we generate a random msgID by hashing a combination of the VIN,current time,and the vehicle location.The message identifier is very important for various reasons:A copy of the msgID is cached by V AHS participants so as to avoid counting the same information twice during a query reso-lution;this is also true for the identifier of POST requests, so that the same alert is not registered twice in the same peer.Also,a corresponding reply is identified by the same message identifier as the original query,so that the source peer will know exactly what it is looking for when receiving replies through its V ANET interface.The remaining lines(Lines9-10in Table1)are used only in VITP requests that carry intermediate results during V AHS-computation phase or in POST messages.The Content-Length header declares the size of the data carried by the request. The actual data follow after the CRLF character.4.SIMULATION STUDY OF VITPIn this section,we present simulation results for VITP performance.Our goal is to investigate the feasibility of VITP and to analyze its performance in large scale vehicular networks.4.1Simulation SetupTo simulate VITP we used the ns-2simulator[2]in com-bination with our own traffic generator tool,which accepts as parameters the simulation time,road length in meters, number of lanes per road,average speed of the vehicles in meters/sec,average gap distance between vehicles on same lane,number of service nodes on the road,and the number of users on the road.The tool uses a simplified traffic model: (i)vehicles may enter or leave the road through evenly dis-tributed entries and exits located along the road every1000 meters;(ii)vehicles can change their speeds and lanes in-dependently of other vehicles,and(iii)vehicles are evenly distributed on the road;once a vehicle leaves the road a new vehicle enters the road randomly.In the following simula-tion scenarios,we generated traffic for a25km-long highway with3lanes.The average vehicle speed is20m/s and the simulation time is set to500seconds.For the purposes of this study,we choose as wireless medium an802.11-compliant network with a data transmission rate of11Mb and a transmission range of250meters1.To al-low vehicles to maintain neighbor connectivity,each vehicle broadcasts a Hello packet every period selected randomly from the range of0.75to1.25seconds.The received signal-strength threshold used in maintaining information about neighbors is set to distances below200meters in order to accommodate with the fast dynamics of the network and to maintain consistency in neighborhood information.Once a vehicle enters the road,it initiates its query at a random time selected uniformly over its remaining simulation time. The vehicle re-sends the query if no answer is received within a specified timeout of10seconds.As mentioned earlier,VITP messages are forwarded to their destination region with geographic routing.In doing this,we select the next vehicle in the route to be the one that is closest to the target destination.If a vehicle fails three consecutive times in transmitting the message to its next hop,it selects another neighboring vehicle.After trying。