Network Working Group S. Kelly Request for Comments: 4772 Aruba Networks Category: Informational December 2006 Security Implications of Using the Data Encryption Standard (DES) Status of This Memo
This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
Copyright Notice
Copyright (C) The IETF Trust (2006).
Abstract
The Data Encryption Standard (DES) is susceptible to brute-force
attacks, which are well within the reach of a modestly financed
adversary. As a result, DES has been deprecated, and replaced by the Advanced Encryption Standard (AES). Nonetheless, many applications
continue to rely on DES for security, and designers and implementers continue to support it in new applications. While this is not always inappropriate, it frequently is. This note discusses DES security
implications in detail, so that designers and implementers have all
the information they need to make judicious decisions regarding its
use.
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Table of Contents
1. Introduction (3)
1.1. Executive Summary of Findings and Recommendations (4)
1.1.1. Recommendation Summary (4)
2. Why Use Encryption? (5)
3. Real-World Applications and Threats (6)
4. Attacking DES (8)
4.1. Brute-Force Attacks (9)
4.1.1. Parallel and Distributed Attacks (10)
4.2. Cryptanalytic Attacks (10)
4.3. Practical Considerations (12)
5. The EFF DES Cracker (12)
6. Other DES-Cracking Projects (13)
7. Building a DES Cracker Today (14)
7.1. FPGAs (15)
7.2. ASICs (16)
7.3. Distributed PCs (16)
7.3.1. Willing Participants (17)
7.3.2. Spyware and Viruses and Botnets (oh my!) (18)
8. Why is DES Still Used? (19)
9. Security Considerations (20)
10. Acknowledgements (21)
Appendix A. What About 3DES? (22)
A.1. Brute-Force Attacks on 3DES (22)
A.2. Cryptanalytic Attacks Against 3DES (23)
A.2.1. Meet-In-The-Middle (MITM) Attacks (23)
A.2.2. Related Key Attacks (24)
A.3. 3DES Block Size (25)
Informative References (25)
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1. Introduction
The Data Encryption Standard [DES] is the first encryption algorithm approved by the U.S. government for public disclosure. Brute-force
attacks became a subject of speculation immediately following the
algorithm’s release into the public sphere, and a number of
researchers published discussions of attack feasibility and explicit brute-force attack methodologies, beginning with [DH77].
In the early to mid 1990s, numerous additional papers appeared,
including Wiener’s "Efficient DES Key Search" [WIEN94], and "Minimal Key Lengths for Symmetric Ciphers to Provide Adequate Commercial
Security" [BLAZ96]. While these and various other papers discussed
the theoretical aspects of DES-cracking machinery, none described a
specific implementation of such a machine. In 1998, the Electronic
Frontier Foundation (EFF) went much further, actually building a
device and freely publishing the implementation details for public
review [EFF98].
Despite the fact that the EFF clearly demonstrated that DES could be brute-forced in an average of about 4.5 days with an investment of
less than $250,000 in 1998, many continue to rely on this algorithm
even now, more than 8 years later. Today, the landscape is
significantly different: DES can be broken by a broad range of
attackers using technologies that were not available in 1998,
including cheap Field Programmable Gate Arrays (FPGAs) and botnets
[BOT05]. These and other attack methodologies are described in
detail below.
Given that the Advanced Encryption Standard [AES] has been approved
by the U.S. government (under certain usage scenarios) for top-secret applications [AES-NSA], and that triple DES (3DES) is not susceptible to these same attacks, one might wonder: why even bother with DES
anymore? Under more ideal circumstances, we might simply dispense
with it, but unfortunately, this would not be so simple today. DES
has been widely deployed since its release in the 1970s, and many
systems rely on it today. Wholesale replacement of such systems
would be very costly. A more realistic approach entails gradual
replacement of these systems, and this implies a term of backward
compatibility support of indefinite duration.
In addition to backward compatibility, in isolated instances there
may be other valid arguments for continued DES support. Still,
reliance upon this deprecated algorithm is a serious error from a
security design perspective in many cases. This note aims to clarify the security implications of this choice given the state of
technology today, so that developers can make an informed decision as to whether or not to implement this algorithm.
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1.1. Executive Summary of Findings and Recommendations
For many years now, DES usage has been actively discouraged by the
security area of the IETF, but we nevertheless continue to see it in use. Given that there are widely published accounts of real attacks and that we have been vocally discouraging its use, a question
arises: why aren’t people listening? We can only speculate, but one possibility is that they simply do not understand the extent to which DES has been marginalized by advancing cryptographic science and
technology. Another possibility is that we have not yet been
appropriately explicit and aggressive about this. With these
particular possibilities in mind, this note sets out to dispel any
remaining illusions.
The depth of background knowledge required to truly understand and
fully appreciate the security risks of using DES today is somewhat
daunting, and an extensive survey of the literature suggests that
there are very few published materials encompassing more than a
fraction of the considerations all in one place, with [CURT05] being one notable exception. However, even that work does not gather all
of the pieces in such a way as to inform an implementer of the
current real-world risks, so here we try to fill in any remaining
gaps.
For convenience, the next section contains a brief summary of
recommendations. If you don’t know the IETF’s current position on
DES, and all you want is a summary, you may be content to simply read the recommendation summary section, and skip the rest of the
document. If you want a more detailed look at the history and
current state-of-the-art with respect to attacking DES, you will find that in subsequent sections.
1.1.1. Recommendation Summary
There are several ways to attack a cryptographic algorithm, from
simple brute force (trying each key until you find the right one) to more subtle cryptanalytic approaches, which take into account the
internal structure of the cipher. As noted in the introduction, a
dedicated system capable of brute-forcing DES keys in less than 5
days was created in 1998. Current "Moore’s Law" estimates suggest
that a similar machine could be built today for around $15,000 or
less, and for the cost of the original system (?$250,000) we could
probably build a machine capable of cracking DES keys in a few hours. Additionally, there have been a number of successful distributed
attacks on DES [CURT05], and with the recent arrival of botnets
[BOT05], these results are all the more onerous. Furthermore, there are a number of cryptanalytic attacks against DES, and while some of Kelly Informational [Page 4]
these remain purely theoretical in nature at present, at least one
was recently implemented using a FPGA that can deduce a DES key in
12-15 hours [FPL02]. Clearly, DES cannot be considered a "strong"
cryptographic algorithm by today’s standards.
To summarize current recommendations on using DES, the simple answer is "don’t use it - it’s not safe." While there may be use cases for which the security of DES would be sufficient, it typically requires a security expert to determine when this is true. Also, there are
much more secure algorithms available today (e.g., 3DES, AES) that
are much safer choices. The only general case in which DES should
still be supported is when it is strictly required for backward
compatibility, and when the cost of upgrading outweighs the risk of
exposure. However, even in these cases, recommendations should
probably be made to phase out such systems.
If you are simply interested in the current recommendations, there
you have it: don’t use DES. If you are interested in understanding
how we arrive at this conclusion, read on.
2. Why Use Encryption?
In order to assess the security implications of using DES, it is
useful and informative to review the basic rationale for using
encryption. In general, we encrypt information because we desire
confidentiality. That is, we want to limit access to information, to keep something private or secret. In some cases, we want to share
the information within a limited group, and in other cases, we may
want to be the sole owner of the information in question.
Sometimes, the information we want to protect has value only to the
individual (e.g., a diary), and a loss of confidentiality, while
potentially damaging in some limited ways, would typically not be
catastrophic. In other cases, the information might have significant financial implications (e.g., a company’s strategic marketing plan). And in yet others, lives could be at stake.
In order to gauge our confidentiality requirements in terms of
encryption strength, we must assess the value of the information we
are trying to protect, both to us and to a potential attacker. There are various metrics we can employ for this purpose:
o Cost of confidentiality loss: What could we lose if an adversary
were to discover our secret? This gives some measure of how much effort we should be willing to expend to protect the secret.
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o Value to adversary: What does the attacker have to gain by
discovering our secret? This gives some measure of how much an
adversary might reasonably be willing to spend to learn the
secret.
o Window of opportunity: How long does the information have value to an adversary? This gives some measure of how acceptable a
weakness might be. For example, if the information is valuable to an attacker for months and it takes only days to break the
encryption, we probably need much stronger encryption. On the
other hand, if the window of opportunity is measured in seconds,
then an encryption algorithm that takes days to break may be
acceptable.
There are certainly other factors we would consider in conducting a
comprehensive security analysis, but these are enough to give a
general sense of important questions to answer when evaluating DES as
a candidate encryption algorithm.
3. Real-World Applications and Threats
Numerous commonly used applications rely on encryption for
confidentiality in today’s Internet. To evaluate the sufficiency of a given cryptographic algorithm in this context, we should begin by
asking some basic questions: what are the real-world risks to these
applications, i.e., how likely is it that an application might
actually be attacked, and by whom, and for what reasons?
While it is difficult to come up with one-size-fits-all answers based on general application descriptions, we can easily get some sense of the relative threat to many of these applications. It is important
to note that what follows is not an exhaustive enumeration of all
likely threats and attacks, but rather, a sampling that illustrates
that real threats are more prevalent than intuition might suggest.
Here are some examples of common applications and related threats:
o Site-to-site VPNs: Often, these are used to connect geographically separate corporate offices. Data traversing such links is often
business critical, and sometimes highly confidential. The FBI
estimates that every year, billions of U.S. dollars are lost to
foreign competitors who deliberately target economic intelligence in U.S. industry and technologies [FBI06]. Searching for
’corporate espionage’ in Google yields many interesting links,
some of which indicate that foreign competitors are not the only
threat to U.S. businesses. Obviously, this threat can be
generalized to include businesses of any nationality.
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o Remote network access for business: See previous item.
o Webmail/email encryption: See Site-to-site VPNs.
o Online banking: Currently, the most common threat to online
banking is in the form of "phishing", which does not rely on
breaking session encryption, but instead relies on tricking users into providing their account information. In general, direct
attacks on session encryption for this application do not scale
well. However, if a particular bank were known to use a weak
encryption algorithm for session security, it might become
worthwhile to develop a broader attack against that bank. Given
that organized criminal elements have been found behind many
phishing attacks, it is not difficult to imagine such scenarios.
o Electronic funds transfers (EFTs): The ability to replay or
otherwise modify legitimate EFTs has obvious financial incentives (and implications). Also, an industrial spy might see a great
deal of intelligence value in the financial transactions of a
target company.
o Online purchases (E-commerce): The FBI has investigated a number
of organized attacks on e-commerce applications [FBI01]. If an
attacker has the ability to monitor e-commerce traffic directed to a large merchant that relies on weak encryption, the attacker
could harvest a great deal of consumer credit information. This
is the sort of data "phishers" currently harvest on a much smaller scale, so one can easily imagine the value of such a target.
o Internet-based VoIP applications (e.g., Skype): While many uses of this technology are innocuous (e.g., long distance calls to family members), VoIP technology is also used for business purposes (see discussion of FBI estimates regarding corporate espionage above). o Cellular telephony: Cell phones are very common, and are
frequently used for confidential conversations in business,
medicine, law enforcement, and other applications.
o Wireless LAN: Wireless technology is used by many businesses,
including the New York Stock Exchange [NYSE1]. The financial
incentives for an attacker are significant in some cases.
o Personal communications (e.g., secure instant messaging): Such
communication may be used for corporate communications (see
industrial espionage discussion above), and may also be used for
financial applications such as stock/securities trading. This has both corporate/industrial espionage and financial implications. Kelly Informational [Page 7]
o Laptop hard-drive encryption: See discussion on corporate/
industrial espionage above. Also, consider that stolen and lost
laptops have been cited for some of the more significant losses of control over sensitive personal information in recent years,
notably the Veterans Affairs data loss [VA1].
There are real-world threats to everyday encryption applications,
some of which could be very lucrative to an attacker (and by
extension, very costly to the victim). It is important to note that if some of these attacks are infrequent today, it is precisely
because the threats are recognized, and appropriately strong
cryptographic algorithms are used. If "weak" cryptographic
algorithms were to be used instead, the implications are indeed
thought-provoking.
In keeping with the objectives of this document, it is important to
note that the U.S. government has never approved the use of DES for
anything but unclassified applications. While DES is still approved for unclassified uses until May 19, 2007, the U.S. government clearly sees the need to move to higher ground. For details on the National Institute of Standards and Technology (NIST) DES Transition plan, see [NIST-TP]. Despite this fact, DES is still sometimes chosen to
protect some of the applications described above. Below, we discuss why this should, in many cases, be remedied.
4. Attacking DES
DES is a 64-bit block cipher having a key size of 56 bits. The key
actually has 64 bits (matching the block size), but 1 bit in each
byte has been designated a ’parity’ bit, and is not used for
cryptographic purposes. For a full discussion of the history of DES along with an accessible description of the algorithm, see [SCHN96].
A detailed description of the various types of attacks on
cryptographic algorithms is beyond the scope of this document, but
for clarity, we provide the following brief descriptions. There are two general aspects of attacks we must consider: the form of the
inputs/outputs along with how we might influence them, and the
internal function of the cryptographic operations themselves.
In terms of input/output form, some of the more commonly discussed
attack characteristics include the following:
o known plaintext - the attacker knows some of the plaintext
corresponding to some of the ciphertext
o ciphertext-only - only ciphertext is available to the attacker,
who has little or no information about the plaintext
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o chosen plaintext - the attacker can choose which plaintext is
encrypted, and obtain the corresponding ciphertext
o birthday attacks - relies on the fact that for N elements,
collisions can be expected in ?sqrt(N) randomly chosen samples;
for systems using CBC mode with random Initialization Vectors
(IVs), ciphertext collisions can be expected in about 2^28
samples. Such collisions leak information about the corresponding plaintexts: if the same cryptographic key is used, then the xor of the IVs is equal to the xor of the plaintexts.
o meet-in-the-middle attacks - leverages birthday characteristic to precompute potential key collision values
Due to the limited scope of this document, these are very brief
descriptions of very complex subject matter. For more detailed
discussions on these and many related topics, see [SCHN96], [HAC], or [FERG03].
As for attack characteristics relating to the operational aspects of cipher algorithms, there are essentially two broad classes we
consider: cryptanalytic attacks, which exploit some internal
structure or function of the cipher algorithm, and brute-force
attacks, in which the attacker systematically tries keys until the
right one is found. These could alternatively be referred to as
white box and black box attacks, respectively. These are discussed
further below.
4.1. Brute-Force Attacks
In general, a brute-force attack consists of trying each possible key until the correct key is found. In the worst case, this will require 2^n steps for a key size of n bits, and on average, it will require
2^n-1 steps. For DES, this implies 2^56 encryption operations in the worst case, and 2^55 encryption operations on average, if we assume
no shortcuts exist. As it turns out, the complementation property of DES provides an attack that yields a reduction by a factor of 2 for a chosen plaintext attack, so this attack requires an average of 2^54
encryption operations.
Above, we refer to 2^n ’steps’; note that what a ’step’ entails
depends to some extent on the first attack aspect described above,
i.e., what influence and knowledge we have with respect to input/
output forms. Remember, in the worst case, we will be performing
72,057,594,037,927,936 -- over 72 quadrillion -- of these ’steps’.
In the most difficult case, we have ciphertext only, and no knowledge of the input, and this is very important.
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If the input is effectively random, we cannot tell by simply looking at a decrypted block whether we’ve succeeded or not. We may have to resort to other potentially expensive computation to make this
determination. While the effect of any additional computation will
be linear across all keys, repeating a large amount of added
computation up to 72 quadrillion times could have a significant
impact on the cost of a brute-force attack against the algorithm.
For example, if it takes 1 additional microsecond per computation,
this will add almost 101 days to our worst-case search time, assuming a serial key search.
On the other hand, if we can control the input to the encryption
function (known plaintext), we know precisely what to expect from the decryption function, so detecting that we’ve found the key is
straightforward. Alternatively, even if we don’t know the exact
input, if we know something about it (e.g., that it’s ASCII), with
limited additional computation we can infer that we’ve most likely
found a key. Obviously, which of these conditions holds may
significantly influence attack time.
4.1.1. Parallel and Distributed Attacks
Given that a brute-force attack involves systematically trying keys
until we find the right one, it is obviously a good candidate for
parallelization. If we have N processors, we can find the key
roughly N times faster than if we have only 1 processor. This
requires some sort of centralized control entity that distributes the work and monitors the search process, but is quite straightforward to implement.
There are at least two approaches to parallelization of a brute-force attack on a block cipher: the first is to build specialized high-
speed hardware that can rapidly cycle through keys while performing
the cryptographic and comparison operations, and then replicate that hardware many times, while providing for centralized control. The
second involves using many copies of general purpose hardware (e.g., a PC), and distributing the load across these while placing them
under the control of one or more central systems. Both of these
approaches are discussed further in sections 5 and 6.
4.2. Cryptanalytic Attacks
Brute-force attacks are so named because they don’t require much
intelligence in the attack process -- they simply try one key after
the other, with little or no intelligent keyspace pruning.
Cryptanalytic attacks, on the other hand, rely on application of some intelligence ahead of time, and by doing so, provide for a
significant reduction of the search space.
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While an in-depth discussion of cryptanalytic techniques and the
resulting attacks is well beyond the scope of this document, it is
important to briefly touch on this area in order to set the stage for subsequent discussion. It is also important to note that, in
general, cryptanalysis can be applied to any cryptographic algorithm with varying degrees of success. However, we confine ourselves here to discussing specific results with respect to DES.
Here is a very brief summary of the currently known cryptanalytic
attacks on DES:
o Differential Cryptanalysis - First discussed by Biham and Shamir, this technique (putting it very simply) analyzes how differences
in plaintext correspond to differences in ciphertext. For more
detail, see [BIH93].
o Linear Cryptanalysis - First described by Matsui, this technique
uses linear approximations to describe the internal functions of
DES. For more detail, see [MAT93].
o Interpolation Attack - This technique represents the S-boxes of
DES with algebraic functions, and then estimates the coefficients of the functions. For more information, see [JAK97].
o Key Collision Attack - This technique exploits the birthday
paradox to produce key collisions [BIH96].
o Differential Fault Analysis - This attack exploits the electrical characteristics of the encryption device, selectively inducing
faults and comparing the results with uninfluenced outputs. For
more information, see [BIH96-2].
Currently, the best publicly known cryptanalytic attacks on DES are
linear and differential cryptanalysis. These attacks are not
generally considered practical, as they require 2^43 and 2^47 known
plaintext/ciphertext pairs, respectively. To get a feel for what
this means in practical terms, consider the following:
o For linear cryptanalysis (the more efficient of the two attacks), the attacker must pre-compute and store 2^43 ciphertexts; this
requires 8,796,093,022,208 (almost 9 trillion) encryption
operations.
o Each ciphertext block is 8 bytes, so the total required storage is 70,368,744,177,664 bytes, or about 70,369 gigabytes of storage.
If the plaintext blocks cannot be automatically derived, they too must be stored, potentially doubling the storage requirements. Kelly Informational [Page 11]
o The 2^43 known plaintext blocks must be somehow fed to the device under attack, and that device must not change the encryption key
during this time.
Clearly, there are practical issues with this attack. Still, it is
sobering to look at how much more realistic 70,000 gigabytes of
storage is today than it must have seemed in 1993, when Matsui first proposed this attack. Today, 400-GB hard drives can be had for
around $0.35/gigabyte. If we only needed to store the known
ciphertext, this amounts to ?176 hard drives at a cost of less than
$25,000. This is probably practical with today’s technology for an
adversary with significant financial resources, though it was
difficult to imagine in 1993. Still, numerous other practical issues remain.
4.3. Practical Considerations
Above, we described several types of attacks on DES, some of which
are more practical than others, but it’s very important to recognize that brute force represents the very worst case, and cryptanalytic
attacks can only improve on this. If a brute-force attack against a given DES application really is feasible, then worrying about the
practicality of the other theoretical attack modes is just a
distraction. The bottom line is this: if DES can be brute-forced at a cost the attacker can stomach today, this cost will invariably come down as technology advances.
5. The EFF DES Cracker
On the question as to whether DES is susceptible to brute-force
attack from a practical perspective, the answer is a resounding and
unequivocal "yes". In 1998, the Electronic Frontier Foundation
financed the construction of a "DES Cracker", and subsequently
published "Cracking DES" [EFF98]. For a cost of less than $250,000, this system can find a 56-bit DES key in the worst-case time of
around 9 days, and in 4.5 days on average.
Quoting from [EFF98],
"The design of the EFF DES Cracker is simple in concept. It consists of an ordinary personal computer connected with a large array of
custom chips. Software in the personal computer instructs the custom chips to begin searching, and interacts with the user. The chips run without further help from the software until they find a potentially interesting key, or need to be directed to search a new part of the
key space. The software periodically polls the chips to find any
potentially interesting keys that they have turned up.
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The hardware’s job isn’t to find the answer. but rather to eliminate most of the answers that are incorrect. Software is then fast enough to search the remaining potentially-correct keys, winnowing the false positives from the real answer. The strength of the machine is that it replicates a simple but useful search circuit thousands of times, allowing the software to find the answer by searching only a tiny
fraction of the key space.
As long as there is a small bit of software to coordinate the effort, the problem of searching for a DES key is ’highly parallelizable’.
This means the problem can be usefully solved by many machines
working in parallel, simultaneously. For example, a single DES-
Cracker chip could find a key by searching for many years. A
thousand DES-Cracker chips can solve the same problem in one
thousandth of the time. A million DES-Cracker chips could
theoretically solve the same problem in about a millionth of the
time, though the overhead of starting each chip would become visible in the time required. The actual machine we built contains 1536
chips."
This project clearly demonstrated that a practical system for brute
force DES attacks was well within reach of many more than previously assumed. Practically any government in the world could easily
produce such a machine, and in fact, so could many businesses. And
that was in 1998; the technological advances since then have greatly reduced the cost of such a device. This is discussed further below.
6. Other DES-Cracking Projects
In the mid-1990s, many were interested in whether or not DES was
breakable in a practical sense. RSA sponsored a series of DES
Challenges over a 3-year period beginning January of 1997. These
challenges were created in order to help underscore the point that
cryptographic strength limitations imposed by the U.S. government’s
export policies were far too modest to meet the security requirements of many users.
The first DES challenge was solved by the DESCHALL group, led by
Rocke Verser, Matt Curtin, and Justin Dolske [CURT05][RSA1]. They
created a loosely-knit distributed effort staffed by volunteers and
backed by Universities and corporations all over the world who
donated their unused CPU cycles to the effort. They found the key in 90 days.
The second DES challenge was announced on December 19, 1997
[RSA2][CURT05], and on February 26, 1998, RSA announced a winner.
This time, the challenge was solved by group called https://www.doczj.com/doc/f715876996.html, Kelly Informational [Page 13]
working together with the EFF, in a total of 39 days [RSA3] [CURT05]. This group coordinated 22,000 participants and over 50,000 CPUs.
The third DES challenge was announced on December 22, 1998
[RSA4][CURT05], and on January 19, 1999, RSA announced the winner.
This time, the challenge was again solved by https://www.doczj.com/doc/f715876996.html, working together with the EFF, in a total of 22 hours [RSA5]. This was a
dramatic improvement over the second challenge, and should give some idea of where we’re headed with respect to DES.
7. Building a DES Cracker Today
We’ve seen what was done in the late 1990s -- what about today? A
survey of the literature might lead one to conclude that this topic
is no longer interesting to cryptographers. Hence, we are left to
infer the possibilities based on currently available technologies.
One way to derive an approximation is to apply a variation on
"Moore’s Law": assume that the cost of a device comparable to the one built by the EFF would be halved roughly every N months. If we take N=18, then for a device costing $250,000 at the end of 1998, this
would predict the following cost curve:
o mid-2000............: $125,000
o beginning of 2002...: $62,500
o mid-2003............: $31,250
o beginning of 2006...: $15,625
It’s important to note that strictly speaking, "Moore’s Law" is more an informal approximation than a law, although it has proven to be
uncannily accurate over the last 40 years or so. Also, some would
disagree with the use of an 18-month interval, preferring a more
conservative 24 months instead. So, these figures should be taken
with the proverbial grain of salt. Still, it’s important to
recognize that this is the cost needed not to crack one key, but to
get into the key-cracking business. Offering key-cracking services
and keeping the machine relatively busy would dramatically decrease
the cost to a few hundred dollars per unit or less.
Given that such calculations roughly hold for other computing
technologies over the same time interval, the estimate above does not seem too unreasonable, and is probably within a factor of two of
today’s costs. Clearly, this would seem to indicate that DES-
cracking hardware is within reach of a much broader group than in
1998, and it is important to note that this assumes no design or
algorithm improvements since then.
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To put this in a slightly different light, let’s consider the typical rendition of Moore’s Law for such discussions. Rather than
considering shrinking cost for the same capability, consider instead increasing capability for the same cost (i.e., doubling circuit
densities every N months). Again choosing N=18, our DES-cracking
capability (in worst-case time per key) could be expected to have
approximately followed this performance curve over the last 7 or so
years:
o 1998................: 9 days
o mid-2000............: 4.5 days
o beginning of 2002...: 2.25 days
o mid-2003............: 1.125 days
o beginning of 2006...: 0.5625 days
That’s just over a half-day in the worst case for 2006, and under 7
hours on average. And this, for an investment of less than $250,000. It’s also very important to note that we are talking about worst-case and average times here - sometimes, keys will be found much more
quickly. For example, using such a machine, 1/4 of all possible DES keys will be found within 3.375 hours. 1/8 of the keys will be found in less than 1 hour and 42 minutes. And this assumes no algorithmic improvements have occurred. And again, this is an estimate; your
actual mileage may vary, but the estimate is probably not far from
reality.
7.1. FPGAs
Since the EFF device first appeared, Field Programmable Gate Arrays
(FPGAs) have become quite common, and far less costly than they were in 1998. These devices allow low-level logic programming, and are
frequently used to prototype new logic designs prior to the creation of more expensive custom chips (also known as Application Specific
Integrated Circuits, or ASICs). They are also frequently used in
place of ASICs due to their lower cost and/or flexibility. In fact, a number of embedded systems implementing cryptography have employed FPGAs for this purpose.
Due to their generalized nature, FPGAs are naturally slower than
ASICs. While the speed difference varies based on many factors, it
is reasonable for purposes of this discussion to say that well-
designed FPGA implementations typically perform cryptographic
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operations at perhaps 1/4 the speed of well-designed ASICs performing the same operations, and sometimes much slower than that. The
significance of this comparison will become obvious shortly.
In our Moore’s Law estimate above, we noted that the cost
extrapolation assumes no design or algorithm improvements since 1998. It also implies that we are still talking about a brute-force attack. In section 4 ("Attacking DES"), we discussed several cryptanalytic
attacks, including an attack that employs linear cryptanalysis
[MAT93]. In general, this attack has been considered impractical,
but in 2002, a group at Universite Catholique de Louvain in Belgium
built a DES cracker based on linear cryptanalysis, which, employing a single FPGA, returns a DES key in 12-15 hours [FPL02].
While there are still some issues of practicality in terms of
applying this attack in the real world (i.e., the required number of known plaintext-ciphertext pairs), this gives a glimpse of where
technology is taking us with respect to DES attack capabilities.
7.2. ASICs
Application Specific Integrated Circuits are specialized chips,
typically optimized for a particular set of operations (e.g.,
encryption). There are a number of companies that are in the
business of designing and selling cryptographic ASICs, and such chips can be had for as little as $15 each at the low end. But while these chips are potentially much faster than FPGAs, they usually do not
represent a proportionally higher threat when it comes to
DES-cracking system construction.
The primary reason for this is cost: it currently costs more than
$1,000,000 to produce an ASIC. There is no broad commercial market
for crypto-cracking ASICs, so the number a manufacturer could expect to sell is probably small. Likewise, a single attacker is not likely to require more than a few of these. The bottom line: per-chip costs would be very high; when compared to the costs of FPGAs capable of
similar performance, the FPGAs are clear winners. This doesn’t mean such ASICs have never been built, but the return is probably not
worth the investment for the average attacker today, given the other available options.
7.3. Distributed PCs
Parallel processing is a powerful tool for conducting brute-force
attacks against a block cipher. Since each key can be tested
independently, the keyspace can easily be carved up and distributed
across an arbitrary number of processors, all of which are running
identical code. A central "control" processor is required for
Kelly Informational [Page 16]
distributing tasks and evaluating results, but this is
straightforward to implement, and this paradigm has been applied to
many computing problems.
While the EFF demonstrated that a purpose-built system is far
superior to general purpose PCs when applied to cracking DES, the
DESCHALL effort [CURT05][RSA1] aptly demonstrated that the idle
cycles of everyday users’ PCs could be efficiently applied to this
problem. As noted above, https://www.doczj.com/doc/f715876996.html, teamed with the EFF group
to solve the third RSA DES Challenge using a combination of PCs and
the EFF’s "Deep Crack" machine to find a DES key in 22 hours. And
that was using 1999 technologies.
Clearly, PCs have improved dramatically since 1999. At that time,
state-of-the-art desktops ran at around 800MHz. Today, desktop PCs
commonly run at 3-4 times that speed, and supporting technologies
(memory, cache, storage) offer far higher performance as well. Since the https://www.doczj.com/doc/f715876996.html, effort used a broad spectrum of computers (from
early 1990s desktops to state-of-the-art (in 1999) multiprocessors,
according to [DIST99]), it is difficult to do a direct comparison
with today’s technologies. Still, we know that performance has, in
general, followed the prediction of Moore’s Law, so we should expect an improvement on the order of a factor of 8-16 by now, even with no algorithmic improvements
7.3.1. Willing Participants
It is important to note that the https://www.doczj.com/doc/f715876996.html, efforts have relied upon willing participants. That is, participants must explicitly and voluntarily join the effort. It is equally important to note that
only the idle cycles of the enrolled systems are used. Depending on the way in which "idle" is defined, along with the user’s habits and computing requirements, this could have a significant effect on the
contribution level of a given system.
These factors impose significant limitations in terms of scale.
While https://www.doczj.com/doc/f715876996.html, was able to enlist over 100,000 computers from around the world for the third RSA DES Challenge, this is actually a rather small number when compared to 2^56 (over 72 quadrillion)
possible DES keys. And when you consider the goal (i.e., to prove
DES can be cracked), it seems reasonable to assume these same
participants would not willingly offer up their compute cycles for a more nefarious use (like attacking the keys used to encrypt your
online banking session). Hence, this particular model does not
appear to pose a significant threat to most uses of encryption today. However, below, we discuss a variation on this approach that does
pose an immediate threat.
Kelly Informational [Page 17]
7.3.2. Spyware and Viruses and Botnets (oh my!)
"Spyware" is a popular topic in security newsfeeds these days. Most of these applications are intended to display context-sensitive
advertisements to users, and some actually modify a user’s web
browsing experience, directing them to sites of the distributor’s
choice in an effort to generate revenue. There are many names for
this type of software, but for our purposes, we will refer to it
simply as "spyware". And while there are some instances in which
rogue software actually does spy on hapless users and report things
back to the issuer, we do not focus here on such distinctions.
Indeed, what we are more interested in is the broader modality in
which this software functions: it is typically installed without the explicit knowledge and/or understanding of the user, and typically
runs without the user’s knowledge, sometimes slowing the user’s PC to a crawl. One might note that such behavior seems quite surprising in view of the fact that displaying ads to users is actually a light-
weight task, and wonder what this software is actually doing with all those compute cycles.
Worms and viruses are also very interesting: like spyware, these are installed without the user’s knowledge or consent, and they use the
computer in ways the user would not voluntarily allow. And unlike
the spyware that is most common today, this malware usually contains explicit propagation technology by which it automatically spreads.
It is not difficult to imagine where we are going with this: if you
combine these techniques, forcible induction of user machines into an "army" of systems becomes possible. This approach was alluded to in [CURT98] and, in fact, is being done today.
Botnets [BOT05] represent a relatively recent phenomena. Using
various propagation techniques, malware is distributed across a range of systems, where it lies in wait for a trigger of some sort. These "triggers" may be implemented through periodic polling of a
centralized authority, the arrival of a particular date, or any of a large number of other events. Upon triggering, the malware executes its task, which may involve participating in a Distributed Denial of Service (DDoS) attack, or some other type of activity.
Criminal groups are currently renting out botnets for various uses
[CERT01]. While reported occurrences have typically involved using
these rogue networks for DDoS attacks, we would be naive to think
other uses (e.g., breaking encryption keys) have not been considered. Botnets greatly mitigate the scaling problem faced by
https://www.doczj.com/doc/f715876996.html,: it is no longer a volunteer-only effort, and user
activity no longer significantly impedes the application’s progress. This should give us pause.
Kelly Informational [Page 18]
It is very important to clearly recognize the implications of this:
botnets are cheap, and there are lots of PCs out there. You don’t
need the $15,625 that we speculated would be enough to build a copy
of the EFF system today -- you only need a commodity PC on which to
develop the malware, and the requisite skills. Or, you need access
to someone with those things, and a relatively modest sum of cash.
The game has changed dramatically.
8. Why is DES Still Used?
Obviously, DES is not secure by most measures -- why is it still used today? There are probably many reasons, but here are perhaps the
most common:
o Backward compatibility - Numerous deployed systems support DES,
and rather than replace those systems, new systems are implemented with compatibility in mind.
o Performance - Many early VPN clients provided DES as the default
cryptographic algorithm, because PCs of the day suffered a
noticeable performance hit when applying stronger cryptography
(e.g., 3DES).
o Ignorance - People simply do not understand that DES is no longer secure for most uses.
While there are probably other reasons, these are the most frequently cited.
Performance arguments are easily dispensed with today. PCs have more than ample power to implement stronger cryptography with no
noticeable performance impact, and for systems that are resource
constrained, there are strong algorithms that are far better
performers than DES (e.g., AES-128). And while backward
compatibility is sometimes a valid argument, this must be weighed
carefully. At the point where the risk is higher than the cost of
replacement, legacy systems should be abandoned.
With respect to the third reason (ignorance), this note attempts to
address this, and we should continue to make every effort to get the word out. DES is no longer secure for most uses, and it requires
significant security expertise to evaluate those small number of
cases in which it might be acceptable. Technologies exist that put
DES-cracking capability within reach of a modestly financed or
modestly skilled motivated attacker. There are stronger, cheaper,
faster encryption algorithms available. It is time to move on.
Kelly Informational [Page 19]
9. Security Considerations
This entire document deals with security considerations. Still, it
makes sense to summarize a few key points here. It should be clear
by now that the DES algorithm offers little deterrence for a
determined adversary. While it might have cost $250,000 to build a
dedicated DES cracker in 1998, nowadays it can be done for
considerably less. Indeed, botnets are arguably free, if you don’t
count the malware author’s time in your cost computation.
Does this mean DES should never be used? Well, no - but it does mean that if it is used at all, it should be used with extreme care. It
is important to carefully evaluate the value of the information being protected, both to its owner and to an attacker, and to fully grasp
the potential risks. In some cases, DES may still provide an
acceptable level of security, e.g., when you want to encrypt a file
on the family PC, and there are no real threats in your household.
However, it is important to recognize that, in such cases, DES is
much like a cheap suitcase lock: it usually helps honest people
remain honest, but it won’t stop a determined thief. Given that
strong, more efficient cryptographic algorithms (e.g., AES) are
available, it seems the only rational reason to continue using DES
today is for compulsory backward compatibility. In such cases, if
there is no plan for gradually phasing out such products, then, as a security implementer, you can do the following:
o Recommend a phased upgrade approach.
o If possible, use 3DES rather than DES (and in any case, DO NOT
make DES the default algorithm!).
o Replace keys before exceeding 2^32 blocks per key (to avoid
various cryptanalytic attacks).
o If there is a user interface, make users aware of the fact that
the cryptography in use is not strong, and for your particular
application, make appropriate recommendations in this regard.
The bottom line: it is simpler to not use this algorithm than it is
to come up with narrow scenarios in which it might be okay. If you
have legacy systems relying on DES, it makes sense to begin phasing
them out as soon as possible.
Kelly Informational [Page 20]
不必太在意童安格原唱【不必太在意的歌词】 是不是在找这首不必太在意的相关歌词?我这里有哦!下面是!就让小编来我来和你们一起去了解一下相关的资料吧，希望能对你有用哦! 不必太在意的歌词 歌曲：不必太在意 歌手：童安格专辑：一世情缘 别再徘徊沉寂的心灵 别再留恋破碎的回忆 大地迎春雷 抛弃你满腹的忧虑 缤纷的彩虹等着你 别再犹豫等待的心湖 别再沉迷过去的旧梦 暖暖的春风 走向那灿烂的天涯路
耀眼的阳光迎着你你不必太在意 也不必隐瞒自己 你要寻觅亮丽的彩云你不必太在意 也不必隐瞒自己 你要寻觅亮丽的彩云亮丽的彩云 别再犹豫等待的心湖别再沉迷过去的旧梦暖暖的春风 走向那灿烂的天涯路耀眼的阳光迎着你你不必太在意
也不必隐瞒自己 你要寻觅亮丽的彩云 你不必太在意 也不必隐瞒自己 你要寻觅亮丽的彩云 亮丽的彩云 你不必太在意 也不必隐瞒自己 你要寻觅亮丽的彩云 你不必太在意 也不必隐瞒自己 你要寻觅亮丽的彩云 亮丽的彩云 不必太在意的演唱者的信息 童安格，著名歌手、音乐人，1959年7月26日生于台湾高雄，是华语乐坛较早的实力派歌手。集作曲、作词、演唱于一身，是典型的浪漫主义爱情故事的发言人。他于1987
年获台湾最受欢迎男歌星奖。他1996年参加中央电视台春节联欢晚会，演唱歌曲《畅饮回忆》，是国内较早深受欢迎的实力歌手。与王杰、周华健、齐秦并称台湾四大天王(9194年)。童安格演唱过《把根留住》、《耶利亚女郎》、《其实你不懂我的心》等经典歌曲，2011年底，童安格以全新形象与著名的经纪公司点时唱片签约，并成为旗下主推艺人。目前，童安格在内地发展。2012年底，发行他的全新大碟。 感谢您的阅读！
公务员考试全流程 Document number：BGCG-0857-BTDO-0089-2022
广州市直MM为大家解答本次广州市考相关问题 管理提醒：本帖被 the9sun 设置为精华(2011-10-26) 09年考公进入广州市直MM，混迹qzzn多年终上岸，目前在市直组织人事部门任职，直接参与招考各个环节。 此次我所属的单位也有参加招考，看到坛子上很多xdjm挺多疑问，为回报论坛，特为此次市考的面试、资格审查、政审等问题，为大家解答。知无不言 关于大家关心的几个问题，在此一并解答一下 一、资格审查需要准备哪些材料（所有资料都要带原件、复印件） 1. 应届毕业生： 必须带上：身份证+学生证+普通高校毕业生就业推荐表+暂缓协议 其他备用：户口本、计划生育保证书（如果没带就当场写） 2. 社会人员：
必须带上：身份证+户口簿+学历证书+学位证书。 2年经验人员必须带劳动合同；如果没有劳动合同，带上单位工作经历证明+社保记录盖章；如果没有合同又没有证明，带上社保记录盖章 社会人员：带上单位工作经历证明备用 3. 在国有单位工作，必须带单位同意报考证明。 在事业单位工作的事业编，必须带单位同意报考证明。 在事业单位的派遣或者合同制员工，不用带同意报考证明。 二、面试环节需要注意哪些： 大家都知道的就不说了，说几个具体的细节 1.考官一般有10-12人。正面面对而坐，面试时间一个人15-20分钟，4-5个题 2. 面试一般有主考官念题，只念一遍（所以要挺清楚）
3. 考试面前一般都有一张白纸和一只笔。因此允许短时间的思考和列提纲（不过建议不要思考时间太长，15-20秒则ok） 4. 面试着装：自己穿着觉着舒服的正装。现在夏天，男生适合短袖衬衣+西裤，建议不打领带；女生适合套裙或者短袖衬衣+西裤 5. 面试之后，一般会要求到其他办公室回避一下，大概过几分钟，就会把面试成绩当场宣布给你。等面试人员基本结束后，就可以大致算出各自排名了。 三、体检 1. 体检一般是面试后两三天就开始，广州市考有几个定点体检医院，一般是各单位就近选择 2. 体检每个项目由医生填写具体记录和项目结论“合格”或“不合格”。如果有单项不合格，一般是不会录用的。医院也是根据公务员录用的要求来填写是否合格 3. 体检一般第二天或第三天招考单位即可知道结果。不联系考生则为通过了，如果联系考生可能就是要复检
童安格 爱与哀愁演唱：童安格 走在风雨中我不曾回头，只想让自己习惯寂寞。 如果在梦中没有你没有我，能不能够让自己不再难过。 爱并不会是一种罪过，恨也不会是一种解脱。 爱与哀愁对我来说象杯烈酒，美丽却难以承受；点一根烟喝一杯酒能醉多久，醒来后依然是我。 走在风雨中我不曾回头，只想让自己习惯寂寞。 如果在梦中没有你没有我，能不能够让自己不再难过。 爱并不会是一种罪过，恨也不会是一种解脱。 爱与哀愁对我来说象杯烈酒，美丽却难以承受；点一根烟喝一杯酒能醉多久，醒来后依然是我。爱与哀愁对我来说象杯烈酒，美丽却难以承受；点一根烟喝一杯酒能醉多久，醒来后依然是我。走在风雨中我不想回头，能不能够让自己不再难过。 把根留住演唱：童安格 多少脸孔，茫然随波逐流，他们在追寻什么。为了生活，人们四处奔波，却在命运中交错。 多少岁月，凝聚成这一刻，期待着旧梦重圆。万涓成水，终究汇流成河，像一首澎湃的歌。 一年过了一年，啊~ 一生只为这一天，让血脉再相连，擦干心中的血和泪痕，留住我们的根。 多少岁月，凝聚成这一刻，期待着旧梦重圆。万涓成水，终究汇流成河，像一首澎湃的歌。 一年过了一年，啊~ 一生只为这一天，让血脉再相连，擦干心中的血和泪痕，留住我们的根。 草原词曲：童安格演唱：童安格 小孩你问我是从哪儿来，我说那秘密挂在那朵云彩 我问你小孩，谁给你胸前的玉块，他说他不知是谁将它生了下来 小孩你问我为何要皱着眉，我说我曾经辜负一个姐姐 我问你小孩为何要流着泪，他说他心爱的小羊迷路没能回来 青山和绿湾，埋藏了所有的忧伤；天空和海洋，哪里才是梦乡。 那草原，那一片草原就是你我的家。那草原，那一片草原就是你我的家。 青山和绿湾，埋藏了所有的忧伤；天空和海洋，哪里才是梦乡。 那草原，那一片草原就是你我的家。那草原，那一片草原就是你我的家。 那草原，那一片草原就是你我的家。那草原，那一片草原就是你我的家。 小孩你问我何时会再有笑容，我说当我再看到姐姐的脸。 花瓣雨演唱：童安格 爱一个人可以爱多久，心痛到那里才是尽头，花瓣雨，像我的情衷。 誓言怎样说才不会错，拥抱到天明算不算多，花瓣雨，飘落在（我）身后。 花瓣雨，就像你牵绊着我，失去了你，只会在风中堕落。 你的谎言像颗泪水，晶莹夺目却叫人心碎，花瓣雨，飘落在（我）身后。 花瓣雨，就像你牵绊着我，失去了爱，只会在风中堕落。 你的谎言像颗泪水，晶莹夺目却叫人心碎，花瓣雨，飘落在（我）身后。 花瓣雨，就像你牵绊着我，失去了爱，只会在风中堕落。 花瓣雨，飘落在我身后。
公务员考试的流程 一、确定为面试对象 公务员面试是在笔试之后进行，笔试合格者才能进入面试。面试由中央国家机关、省、市、县（市、区）组织部门、人事部门组织实施。笔试结束后，由人事考试机构统一划定笔试专业科目合格分数线和公共科目最低录用控制分数线，各级组织、人事部门在上线人员中根据各招考职位报考者的笔试成绩，从高分到低分按招考职位考录计划的1:3确定面试对象。面试成绩满分为100分，合格分为60分。 面试资格确定方法为： （一）确定笔试分数线 由人事考试机构按照录取1:3的比例，参照调剂因素、资格复核淘汰因素、体检、政审淘汰因素等，确定一个基本的分数线。 （二）成绩排名 上线考生的笔试成绩按照各个职位从高到低的原则排名，总分并列的，比较《行测》和《申论》合计分数，分数高者优先。名次并列情况重复计算。 （三）名单公示 按照规定，进入面试的考生名单和成绩排名情况应在网站上予以公布，接受考生和社会各界的监督，公示时间一般为5天，公示未结束不得举行面试考试，在公示期间如有考生被检举违纪，经查实后该考生将被取消面试资格，由后续考生顺序替补。 二、资格复审 面试前，对进入面试的报考人员须进行资格复核。考生一般会接到电话通知，复核地点在当地公布的指定地点。资格复核需要带齐下列手续： （一）20××年全日制普通高校应届毕业生应提供学校核发的就业推荐表、教育部学生司制发的《全国普通高校毕业生就业协议书》、身份证、原户籍等相关证件（证明）原件及复印件。 （二）社会其他人员应提供本人身份证、户口簿、学历、学位证书、单位同意报考证明等相关证件（证明）原件及复印件，按各级组织人事部门规定的时间、地点接受资格审核。 报考者不参加资格审核或提供的证件不全及所提供的证件（证明）与个人网上填报内容不相符者，不得参加面试，因此出现的空缺，在报考该职位的人员中从高分到低分依次替补。面试前3天，取得面试资格的人员如果放弃参加面试，并向报考机关同级组织、人事部门书面确定的，将在报考该职位未进入面试的人员中从高分到低分依次替补。报考公安警察、森林警察的，在资格复审时，同时进行体能测评。 （三）发放通知 经过以上几个环节后，人事考试机构将确定最终正式进入面试的考生名单，考生将得到正式的面试通知书或考试证件，并得到面试的地点、时间和注意事项的通知。
七年级（上）语文第四单元测试卷 总分：100分测试时间120分钟 温馨提示：你现在拿到的试卷满分为100分（含卷面3分），相信只要认真读题、仔细审题、规范答题，一定能够获得一个令自己满意的成绩。 一、语文积累与综合运用（25分） 1、古诗文默写（8分） （1）补写出下列名句中的上句或下句。（4分） ①，青山郭外斜。（孟浩然《过故人庄》） ②山光悦鸟性，。（常建《题破山寺后禅院》） ③何当共剪西窗烛，。（李商隐《夜雨寄北》） ④商女不知亡国恨，。（杜牧《泊秦淮》） （2）默写朱熹《观书有感》（4分） 诗题： ，。 ？。 2、阅读下面的文字，完成（1）--（3）题。（5分） 远方耸立着巍峨的山峰，迂回的小道蜿蜒盘旋，挑石工瘦骨lín（）峋的背影在山间徘徊，我小心冀冀的往山下凝视，不免心惊肉跳，顿觉头晕目眩，山下白雾茏罩，我不禁纳罕是何时所集结的唯美杰作，难道是山峦chuò（）泣所孕育的结晶？ （1）给文中加点的字注音或根据拼音写汉字。（3分） lín（）峋chuò（）泣头晕目眩( ) （2）文中有两个错别字，请找出并改正：改为；（1分） （3）加点字“纳罕”在这里的含义是：（1分） 3、阅读下面这首小诗，完成（1）--（2）题（5分） 成功的花， 人们只惊羡它现时的明艳， 然而当初她的芽儿， 浸透了奋斗的泪泉， 洒满了牺牲的血雨。 （1）这首小诗选自《繁星?春水》，作者是，她是中国现代文学史上第一位著名女作家，她一步入文坛，便以宣扬“”著称。（2分） （2）你从这首诗悟出什么道理？（3分） 4、阅读下列材料，完成（1）--（3）题。（7分） “太阳，太阳，给我们带来七色光彩……我们到这七彩梦，走向未来”。我们几乎是唱
公务员管理科工作工作职责: 1、公务员考核工作 2、公务员奖励工作 3、组织实施公务员培训工作 4、公务员登记(统计)工作 5、公务员辞职审批工作 6、公务员辞退审批工作 7、综合工作 公务员管理科综合工作流程图
公务员考核工作 一、岗位职责 负责完善公务员考核审核制度，拟订并组织实施具体实施办法；负责公务员考核的审核、审批工作。 二、平时考核工作流程及要求 平时考核重点考核公务员日常表现、奖惩、违规违纪以及出勤情况，采取按季度由主管领导或组织人事（政工）部门定期对被考核人作出阶段性评价，填写《公务员平时考核表》，重点记录公务员每季度有关日常表现、奖惩、违规违纪、出勤等方面的异常情况，报地区公务员主管部门备案。 三、定期考核工作流程及要求 （一）定期考核采取年度考核的方式，在每年的11月份进行。 (二)被考核公务员按照职位职责和有关要求进行总结，并在一定围述职；认真总结一年来在德、能、勤、绩、廉等方面表现，填写《考核登记表》。 (三)主管领导在听取群众和公务员本人意见的基础上，根据平时考核情况和个人总结，写出评语，提出考核等次建议和改进提高的要求； (四)对拟定为优秀等次的公务员在本机关围公示； (五)由本机关负责人或者授权的考核委员会确定考核等次；
(六)将考核结果以书面形式通知被考核公务员，并由公务员本人签署意见。 (七)报送审核。各单位考核结束后，将《考核工作总结》，《考核审核备案登记表》和《年度考核中优秀、基本称职、不称职及未定等次中受处分人员》及《考核结果花名册》报送地区公务员局公务员主管部门（公务员管理科）审核备案。 (八)资料归档。年度考核结果复函文件、考核登记表归档保存。 公务员（工作人员）考核工作流程图
很好的歌词哦 玻璃鞋 又再想情形原来多公平谁人如能使我经常欢乐，也能使我哭恋爱是无形如童话精灵无形而能使我心情起伏反而感觉满足我愿为爱作牺牲耗尽了我的真完成童话内戏份现实纵使伤感，破碎公主的心玻璃折射那幻觉幻觉极迷人王子，从来未遇到灰姑娘天神从来未造出玻璃鞋还是相信恋爱幻觉童话拼合爱的方块假如存在幸福玻璃鞋假如神或上天肯安排期望给我只管看一眼只管穿一穿也愉快music 我愿为爱作牺牲耗尽了我的真完成童话内戏份现实纵使伤感，破碎公主的心玻璃折射那幻觉幻觉极迷人王子，从来未遇到灰姑娘天神从来未造出玻璃鞋还是相信恋爱幻觉童话拼合爱的方块假如存在幸福玻璃鞋假如神或上天肯安排期望给我只管看一眼只管穿一穿也愉快王子，从来未遇到灰姑娘天神从来未造出玻璃鞋还是相信恋爱幻觉童话拼合爱的方块假如存在幸福玻璃鞋假如神或上天肯安排成就一对可拥有一刹花一生积蓄我愿买期望跟你只管吻一吻只管想一想也愉快！ 我只在乎你- 邓丽君 如果没有遇见你，我将会是在哪里？日子过得怎么样，人生是否要珍惜？也许认识某一人，过着平凡的日子。不知道会不会，也有爱情甜如蜜？任时光匆匆流去，我只在乎你。心甘情愿感染你的气息。人生几何能够得到知己？失去生命的力量也不可惜。所以我求求你，别让我离开你。除了你，我不能感到，一丝丝情意。如果有那么一天，你说即将要离去。我会迷失我自己，走入无边人海里。不要什么诺言，只要天天在一起。我不能只依靠，片片回忆活下去。任时光匆匆流去，我只在乎你。心甘情愿感染你的气息。人生几何能够得到知己？失去生命的力量也不可惜。所以我求求你，别让我离开你。除了你，我不能感到，一丝丝情意。任时光匆匆流去，我只在乎你。心甘情愿感染你的气息。人生几何能够得到知己？失去生命的力量也不可惜。所以我求求你，别让我离开你。除了你，我不能感到，一丝丝情意。 好心分手(国粤语合唱版) 王力宏 (女):是否很惊讶讲不出说话没错我是说你想分手吗曾给你驯服到就像绵羊何解会反咬你一下你知吗(男):也许该反省不应再说话被放弃的我应有此报吗如果我曾是个坏牧羊人能否再让我试一下抱一下(女):回头望伴你走从来未曾幸福过(男):恨太多没结果往事重提是折磨(女):下半生陪住你怀疑快乐也不多(男):被我伤让你痛(女):好心一早放开我从头努力也坎坷统统不要好过(男):为何唱着这首歌为怨恨而分手问你是否原谅我(女):若注定有一点苦楚不如自己亲手割破(男):回头吧不要走不要这样离开我恨太多没结果往事重提是折磨(女):下半生陪住你怀疑快乐也不多没有心别再拖好心一早放开我从头努力也坎坷统统不要好过
国家公务员考试报名流 程官方回答 LG GROUP system office room 【LGA16H-LGYY-LGUA8Q8-LGA162】
国家公务员考试报名流程官方回答 官方回答 一、申请报名 按照规定的程序和方法组织国家公务员录用考试的报名，是整个公务员录用考试实施流程的重要环节。也是国家公务员录用考试公开、平等原则的具体体现。公务员录用考试的报考于考试主管机关发布招考公告后进行。具体程序如下： （一）正式报名前，参加公务员考试的人员应在规定的时间和地点领取报名所需的各种表格和报考须知资料，认真填写好报名表并了解报考须知。 1．报名表的内容一般包括： （1）个人基本情况：姓名、性别、年龄、籍贯、住址、通讯地址、照片； （2）考试法规定的要求事项，如：有无不良的嗜好，是否受过奖惩或刑事处分等； （3）资历、资格事项：文化程序、工作经历、个人品德习惯、专长爱好、体格与健康状况等； （4）其他事项：婚姻状况、家庭状况、社会关系、个人负担等。 2．报考须知，是指导老先生如何报名的告示，也是对招考公告的详细说明。现把中央国家行政机关录用公务员报考须知的有关内容介绍如下： （1）报考对象 一般除部分京内紧缺专业及其职位允许京外具有城镇户口的全民所有制职工报考外，大多数专业及其职位均由京内城镇户口的全民所有制职工报考。
A．京内报考人员 其一，允许京内及地方党政机关、人大、政协、法院、检察院及全民所有制企事业单位的在职职工报考。 其二，允许档案存放京内有关交流中心，并保留全民所有制职工身份的职工报考。 其三，允许当年度春季毕业的外语、财会、计算机、考古专业研究生和有两年以上工作经历有关专业的北京高校研究生报考，有关京外生源研究生录用后的留京问题,由人事部解决。 其四，允许国务院军转办及双（退）办批准，1994年在京安置但尚未找到安置单位的营以下转业军官及复员军人报考。 其五，允许集体、民办、合资等单位中全民所有制职工报考。 其六，单位地处远郊区县的报考人员，须在报名时或招考过程中，按有关管理权限，出具人事或组织部门同意报考的介绍信或信函，未能出具的，视其情况决定是否允许报考。对允许报考者，贮存到人事部"备选人员库"中，待开来介绍信后，作为"备选人员"予以推荐。 其七，中小学及公安、劳改系统的报考人员，也须在报名时或招考过程中，按照管理权限出具市、部级等所属教育、人事部门同意报考的介绍信或信函。不能出具的，按前述"6"中的类似办法处理。 B．京外报考人员 其一，面向京外招考的部门，其招考对象应符合有关规定中关于京内紧缺专业或特殊工作经历的要求。 其二，京外报考人员均应为全民所有制在职职工。 其三，边远地区及中小学教师或某些特殊行业的京外报考人员，须出具所在省政府人事部门的介绍信。 （2）资格条件（上文已述）
放过自己庄心妍的歌词 放过自己是庄心妍演唱的一首动听伤感的情歌，这首歌曲深受大家的喜欢，是不是在找他的相关的歌词？下面是!我帮你整理了这首歌的歌词相关信息吧!希望能对你有用哦! 放过自己的歌词放过自己-庄心妍 词：林华勇曲：林华勇 你总是越宠越坏 我对你的关怀 都变成了伤害 爱不可能再重来 过程虽然精彩 但感觉已不在 就当我上辈子欠了你 就当这是今生的宿命 也许没有你 我才更爱惜自己 既然我感动不了你 我就放过我自己 你的骄傲和谎言是我离开的动力 既然我改变不了你 至少我可以放弃
分手时才发现我并没有那么爱你 爱不可能再重来 过程虽然精彩 但感觉已不在 就当我上辈子欠了你 就当这是今生的宿命 也许没有你 我才更爱惜自己 既然我感动不了你 我就放过我自己 你的骄傲和谎言是我离开的动力 既然我改变不了你 至少我可以放弃 分手时才发现我并没有那么爱你 既然我感动不了你 我就放过我自己 你的骄傲和谎言是我离开的动力 既然我改变不了你 至少我可以放弃 分手时才发现我并没有那么爱你 放过自己的演唱者信息庄心妍(Ada)，1993年1月9日出生于广东省汕尾市，内地女歌手。
2012年10月29日，发行首支单曲《一万个舍不得》。2013年1月15日，荣获酷狗繁星网新声代歌唱比赛第二名，2013年3月13日，在酷狗音乐独家发行个人原创专辑《一万个舍不得》，2013年5月3日，发行单曲《心有所爱》，2013年6月13日，发行单曲《以后的以后》。 2015年11月8日，在沈阳铁西体育馆举办了自己的第一场甜妍蜜语演唱会。2016年1月5日，在河北体育馆举办了演唱会。2016年4月21日，酷狗首发数字专辑《做最好的我》。2016年10月7日发行第十张原创专辑《Touch Of Love》，包含《孤单坠爱》、《错误的邂逅》等六首主打歌曲。 庄心妍个人演艺经历2004年，一张来自2004年超级女声冠军安又琪的唱片，让庄心妍渐渐地喜欢并熟悉了音乐。 2007年，一首来自卫诗Jill的《可可》，让庄心妍开始慢慢的对粤语歌曲有另一种感觉。最初开始接触QQ音乐，后参加各种语音软件举行的小型K歌比赛，定期翻唱歌曲发布到网站上，后被致力音乐公司签约，成为歌手。签约之后发行了自己的首张EP《填密爱》。 2012年签约致力音乐。2012年10月29日发行首支单曲《一万个舍不得》，一炮走红;11月16日演唱酷狗主题曲《繁星点点》。2013年1月15日获酷狗繁星网新声代歌唱比赛第二名;3月13日酷狗音乐独家发行个人原创大碟《一万
2018年国考报名流程：本文介绍2018年国家公务员考试报考流程。2018年国考报考流程应提前了解，利于把握国考时间安排。 一、报考程序 （一）职位查询 各招录机关的招考人数、具体职位、考试类别、资格条件等，等到报名开始时，及时查阅《中央机关及其直属机构2018年度考试录用公务员招考简章》（此时尚未公布）。 报考人届时可以通过以下网站查阅《招考简章》： 中央机关及其直属机构考试录用公务员专题网站 人力资源和社会保障部门户网站 国家公务员局门户网站 对《招考简章》中的专业、学历、学位、资格条件、基层工作经历以及备注内容等信息需要咨询时，请报考人员直接与招录机关联系，招录机关的咨询电话可以通过上述网站查询。 有关报考政策、报名网络技术和考场考务安排等事宜的详细情况，请参阅《报考指南》。 （二）网上报名 考试报名主要采取网络报名的方式进行。报考人员可登录中央机关及其直属机构考试录用公务员专题网站进行网上报名，也可以通过人力资源和社会保障部门户网站或国家公务员局门户网站上的相关链接登录考录专题网站。 网上报名按以下程序进行： 1、提交报考申请 2、查询资格审查结果 3、查询报名序号 （三）报名确认 通过资格审查的报考人员需要进行报名确认。报名确认采取网上确认的方式进行，报考人员应于规定的期间内在所选考区考试机构网站进行网上报名确认及缴费。未按期参加报名确认并缴费者视为自动放弃考试。 （四）网上打印准考证 报名确认成功后，报考人员应于规定的期间内，登录所选考区考试机构网站下载打印准考证。打印中如遇问题，请与当地公务员考试机构联系解决。 （五）参加笔试 笔试的公共科目包括行政职业能力测验和申论两科。不指定辅导用书，可以参考2018年国家公务员考试一本通（中国出版集团现代教育出版社）。报考中央对外联络部、中央编译局、外交部、文化部、商务部、国家旅游局、国家外国专家局、全国友协、中国贸促会等部门日语、法语、俄语、西班牙语、阿拉伯语、德语、朝鲜语（韩语）、葡萄牙语等8个非通用语职位的人员，还将参加外语水平考试，考试大纲请在考录专题网站和相关招录部门网站查询。 报考中国银监会及其派出机构、中国证监会及其派出机构特殊专业职位的人员以及报考公安机关人民警察职位的人员还将参加专业科目考试，考试大纲请在考录专题网站，中国银监会、中国证监会、公安部网站分别查询。
1、把根留住 多少脸孔茫然随波逐流 他们在追寻什么 为了生活人们四处奔波 却在命运中交错 多少岁月凝聚成这一刻 期待着旧梦重圆 万涓成水终究汇流成河 像一首澎湃的歌 一年过了一年 一生只为这一天 让血脉再相连 擦干心中的血和泪痕 留住我们的根 2、八月桂花香 将要入梦，几番起伏终不平到如今都成烟雨 今夜成空,宛若回首袖底风 幽幽一缕香飘在深深旧梦中繁华若景一生憔悴在风里 回头是无晴也无雨 明月小楼孤独无人诉情衷 人间有我残梦会醒 漫漫长路起伏不能由我 人海漂泊尝尽人情淡薄 热情热心换冷淡冷漠 任多少深情都像寂寞 人随风波只在花开花又落 不管世间沧桑如何 你已乘风去满腹相思都沉默只有桂花香暗飘过 3、白发亲娘 你可是又在村口把我张望 你可是又在窗前把我默想 你的那一根啊老拐杖 是否又把你带到我离去的地方娘啊，娘啊，白发亲娘 儿在天涯 你在故乡 娘啊，娘啊，白发亲娘 黄昏时候 晚风已凉 回去吧，我的娘 儿不能去为你添一件衣裳娘啊，娘啊，白发亲娘。 你可是又在梦中把我挂念 你可是又在灯下为我牵肠 你的那一双老花眼 是否又把别人错看成我的模样 娘啊，娘啊，白发亲娘 春露秋霜 寒来暑往 娘啊，娘啊，白发亲娘 朝思暮想 泪眼迷茫 责怪吧，我的娘 儿想你却不能去把你探望 娘啊，娘啊，白发亲娘 白发亲娘 4、别亦难 相见时难别亦(也)难 东风无力百花残 春蚕到死丝方尽 蜡炬成灰泪始干泪始干 啊!相见难 啊!别亦(也)难 蜡炬成灰泪始干 5、步步高 没有人问我过的好并不好 现实与目标哪个更重要 一分一秒一路奔跑 烦恼一点也没有少 总有人像我辛苦走这遭 孤独与喝彩其实都需要 成败得失谁能预料 热血注定要燃烧 世间自有公道付出总有回报 说到不如做到要做就做最好 世间自有公道付出总有回报 说到不如做到要做就做最好 步步高 6、草原牧歌 辽阔草原，美丽山冈，群群的牛羊 白云悠悠，彩虹灿烂，挂在蓝天上 有个少年，手拿皮鞭，站在草原上 轻轻哼着，草原牧歌，看护着牛和羊 年轻人啊，我想问一问，可否让我可否让我诉说
放过自己的说说150条 1、我决定，放过自己一会儿，太累了，暂时不去想工作上的事情，不去催促，客户的感受也不去在乎了，等我休息好了，精力充沛头脑清晰再去处理。 2、生活已经那么累了，不给自己太高的要求，太多的压力，不时学会给自己找退路，学会放过自己，反而算是善待了自己。 3、一个人，想得太多了，心累的是自己。一个人，追逐得多了，疲惫的是自己。 4、前面的路还很远，你可能会哭，可是必须要走下去，必须不能停。 5、喜欢阳光是因为它很暖暖到了心底暖去了不知名的疼痛。 6、我不敢多想，我怕那个以杯具作为结尾的收局。 7、到了最终仍然要分开，又何必再相遇相识相爱。 8、跟自己说声对不起，因为以往为了别人难为了自己。 9、白云从不向天空承诺去留，却朝夕相伴;风景从不向眼睛诉说永恒，却始终美丽;星星从不向夜晚许诺光明，却努力闪烁;咱俩从不向对方倾诉思念，却永远挂牵。 10、脆弱的人才会四处游说自己的不幸，坚强的人只会不动声色的越加强大。 11、人生路上，不妨试着转弯，看淡得失，善待自己，不为难他
人，也放过自己。得不到的回应，就学会转身，不属于自己的情，洒脱地放，拥有时珍惜，失去后不说遗憾。 12、你知道，什么都会过去的，无论什么。如果能够的话，尽量原谅他人，放过自己。 13、我不是不爱你了，只是把你永远的放在心里。 14、你问她想不想你时她会说不想，其实恰恰相反。 15、半梦半醒的梦境真实的让人难过。不想做梦。不要做梦。太累了。已经那么多事情让人疲乏结果自己的梦都不放过自己。醒过来的时候觉得负能量已经要爆炸了。 16、但愿有人看透你的逞强，给你一个最温暖的怀抱 17、世界上最心痛的感觉，不是失恋，而是我把心给你的时候，你却在欺骗我。 18、此刻的生活并不是我想要的，但确实是我自找的，所以活该也认了。 19、我最大的问题还是对自己不明晰，某些时刻不放过自己，某些时刻又太放纵自己，所以我大多数时候在矛盾里啃啃咬咬，咬累了就拍拍屁股走人，压根儿忘了自己啃咬的初衷。 20、如果你看到面前的阴影，别怕，那是因为你的背后有阳光。 21、如果生活中，有一个人想把你踩在脚下，不要以为生活错待了你。或许，还有十个人想要把你踩在脚下，只是你的强大，让他们没有机会伸出脚来。 22、此刻不玩命，将来命玩你，此刻不努力，未来不给力。
把“根”留住——议小学数学教学的“根”的问题 歌。”“让血脉再相连，留住我们的根！”这是香港著名歌星童安格经典歌曲《把根留住》里的几句歌词。细细品来，真是意味深长。 共同出力量，集中精力研究和编写了新课程。就在短短的三、四年里，全国所有地区、所有学校分批进入了实验区，百万名教师投入到了这场声势浩大的改革之中，全国所有的适龄儿童几乎一个不漏地在学习新课程、接受新教育、学做新公民。 “多少脸孔，随波逐流，他们到底在追寻什么？”是不是在盲目地追新、幼稚地从洋？还是在血脉相连中寻求发展？我想，这个答案是肯定的：这是一场具有深远意义的教育改革；是一次符合我国国情、借鉴外国经验、传承传统精华、血脉紧紧相连的一次大变革。也正是“万涓成水，汇流成河，像一首澎湃的歌。” “传统精华”是我们大中华的民族之“根”；“传承与创新”是我们大中华的改革之路。 我们都是小学数学教师，我们到底应该如何去随波逐流？如何才能真正有效地实施新课程，根据时代需要把小学数学教学工作做得更好？我认为首先要有“把‘根’留住”的思想观念。什么是小学数学教学的“根”呢？我想，小学数学教学的本质就是小学数学教学的“根”。如果我们在新课程实施中能够始终紧紧地把握好小学数学教学的本质性的问题，我们就真正抓住了小学数学教学的根本性问题。 那么，我们怎样才能把握好小学数学教学的本质性的问题呢？那就是要不断地通过学习，进一步理解和精通数学的基本概念，把握有效的数学思想，构建多样的思维方式，培育学生的数学精神；进一步理清“传承与创新”的教学改革发展思路，在基础中求创新。具体说来，我们要从以下五个方面去努力： 一、精通数学的基本概念。 小学阶段的数学概念是最基本的，但也是最重要的概念之一。我们要学生掌握这些基本概念，教师自己首先要精通这些概念。而且，我还认为，一个人他在小学阶段对数学概念能理解透彻，印象深刻，那么，对他将来比较顺利地学习数学，其效果是十分明显的。 据网上资料显示，在高等教育领域里，数学这门课程不仅仅只是理科生学习的，而是几乎所有专业的学生都要学数学，因为它是一门基础课程。还如，凡想在大学一二年级转专业的话，无论是理科类、文科类、医学类、工科类等等，“数学分析”这门课程是必考科目。更如，在高考中，数学是和语文、英语占有同等分数的重要地位，其课程的重要程度更是不言而喻。由此，我就想到，数学对一个小学生的发展前途是何等的至关重要。如果我们的教学对象在小学阶段就连基本的数学概念都搞不清楚，那么，他将来怎么会有能力去参与数学课程的后续学习？怎么能适应国家和社会对人才的选拔机制？等待他们的结果将会是什么？ 这里我再举个小例子进一步说明这个问题：就在前几年，我县元济高级中学有个文科毕业生，姓名：胡玉婷。她报考的是文科，而她在高考中数学却得了满分。再加上她的其它几门学科
录用流程 https://www.doczj.com/doc/f715876996.html, 2009-07-22 14:44:30 国家公务员网 【字体: 大中小】 公务员录用考试的基本程序 公务员录用考试的程序，包括录用考试的准备、笔试面试的操作、笔试面试的评判等。本节侧重从国家行政机关(即用人单位)角度阐述公务员录用考试的基本程序，以让应试者“知彼知己”。让应试者“见树又见林”，明确面试在公务员录用考试中所处的位置，进一步加深对公务员面试的认识。 一、公务员录用考试的准备工作 公务员录用考试的准备工作是公务员录用考试得以进 行的前提，包括编制录用计划、发布空缺公告、考试公告、审查报考者资格等。 1 编制录用计划 公务员的录用计划是指国家行政机关根据实际工作需 要计划录用的公务员人数、专业、所需资格条件、招考范围等。编制录用计划的程序是由各用人部门向同级政府人事部门申报计划，然后由政府人事部门综合平衡后，编制本年度的录用计划，然后逐级报录用考试主管机关批准后实行。
目前，我国公务员录用计划的主要内容是：录用公务员的 总数、不同职位人数的分布、所需公务员的文化程度及数量等。编制公务员录用计划的前提：一是国家核定的机构的编制不满；二是国家批准有增干指标。编制录用计划是在国 家编制管理、综合平衡的前提下进行的，是录用考试的有效前提。 2 发布职位空缺公告 国家行政机关出现职位空缺，报同级政府人事部门批准纳入录用计划后，由公务员考试机构将所空缺的职位的单位、职位、数额等向社会公布，以便有资格者准备或应试。空 缺公告又叫招考公告，是公务员录用考试面向社会的第一步，一般都详细、具体、明确地列出录用机构、录用职位、所需文化程度、所需工作经历、工资待遇等等。空缺公告一般 都通过新闻媒介(报纸、电台、电视等)向社会发布。 3 发布考试公告 政府人事部门在实施公务员录用考试时，成立的临时或常设考试委员会，决定办理考试的具体事项，如：排定考试日程、确定考试地点、拟定考试公告等等。 考试公告是考试机构向社会发布的第二个公告，一般根据具体情况，不定期地发布，其内容一般包括：考试种类、考试科目；报名条件；报考的职位与数额；职务的待遇；
让我们来寻根 第一课时 教学目标： 1通过“寻根的故事”“我是中国人”“歌曲欣赏”等活动渗透爱国主义教育，培养学生的民族自豪感和爱国热情。 2 通过讲述人类起源的神话传说让学生了解我国上下五千年的民间文化。 教学准备： 1 按照第74～75页的内容和第76～77页上的部分内容自制成多媒体课件。 2 课前请三位学生排练小品“寻根”。 3 课前请学生收集有关人类起源的神话传说。 教学过程： 一寻根的故事 1 小品导入：“寻根”。 （旁白一人，演员两人，男女各一名，男孩扮演华侨老人，女孩扮演其孙女。故事讲述的是老华侨年轻时因战乱被迫离开祖国，多年后重返故土之百感交加的感人场面。其中可用多媒体课件播放第一幕中的战乱的印象画面配以演员的表演，第二幕中播放《把根留住》的MTV，演员朗诵《回乡偶书》一诗。总之教师应在课前做充分的准备，将小品的感人之处充分表达出来，才能取得预期的教学效果。） 2 同学们，这个小品给我们讲述了一个什么故事？你从中感受到什么？ 3 像这位老人一样的华侨华裔还有很多，可他们都和这位老人一样，在离开祖国多年后依然要回到祖国的怀抱，请听这样几个故事。 4 提问：这些旅居海外的华人为什么要千里迢迢地回来寻根？你能体会到他们的心情吗？ 5 欣赏并跟唱MTV《我的中国心》。 二我是中国人 1 看到这么多海外华侨来到中国寻根，你们有什么感想？ 2 是啊！祖国在一天天强大起来，作为一名中国人，我们心潮澎湃，热血沸腾，让我们高唱一首《中国人》，向世界证明我们将永远屹立在世界的东方！（播放MTV〈中国人〉） 三我们的根有多深 1 作为一名中国人，我们感到骄傲和自豪；作为一名华夏子孙，我们也应该了解我们五千年的文明甚至更早的故事。老师就很想知道咱们中国人最早最早的祖先是谁？自古以来，人们一直在思考着这个问题。在古代，由于缺乏科学文化知识，人们只能凭借想象创造出许多关于人类起源的神话传说！老师这里就有一个《盘古开天地》的故事，请看！（播放〈盘古开天地〉的动画片） ２听音乐，以小组为单位设计一个以“开天辟地”为主题的小舞蹈进行表演。评一评：哪个小组把盘古氏的那种雄伟气魄表现得更为出色！ ３你还知道哪些关于人类起源的神话传说？说出来给大家听听，并将名称填写在书上。四歌曲欣赏〈龙的传人〉 1教师讲述〈龙的传人〉的故事。 2 让我们共同唱起这首歌，唱出我们每个华夏儿女的精神！ 第二课时 教学目标： 通过本课时的学习，让学生了解到人类的进化过程，看到中华大地早期人类进化的轨迹；引导学生知道先民生活的情景，激发学生对考古的兴趣。
伤感语录夜 1、我不寂寞，我只是一个人而已，我的世界有我一个人就好，已经足够热闹。 2、生活简单就迷人，人心简单就幸福；学会简单其实就是不简单。晚安！ 3、如果一个人的孤独让你学会成熟，那么我宁愿做一个长不大孩子，天天活在幸福当中。 4、谎言与誓言的区别在于，一个是听的人当真了，一个是说的人当真了。 5、一个人走，一个人睡，一个人思索，一个人沉醉。一个人忙，一个人累，一个人烦躁，一个人体会。 6、想哭就哭，想笑就笑，不要因为世界虚伪，你也变得虚伪了。 7、明明是我们的故事，却给了别人一个完美的结局。 8、窗外下着雪，泡一杯咖啡，握到它凉了，才知道又想起了你。我的期待你如何才能明白！ 9、静静的坐在荧屏前，熟悉的打开曾经留下的片段。原来当初最纯真的自己，早已被遗忘在那段风逝的岁月中。
10、星光坠入你眼里，而你却落进我心里。 11、我待你如此温柔，你却说何必强求。 12、愿吹过我的风能再环绕着你，算是借风与你相拥。 13、愿你所有快乐，无需假装。愿你此生尽兴，赤诚善良。祝你岁月无波澜，敬我余生不悲欢。 14、一个人最大的缺点不是自私、多情、野蛮、任性，而是偏执地爱一个不爱自己的人。 15、辗转难眠，就这样睁眼到天亮，有时候觉得为什么要过这般日子，原来是自己太过死心踏地对一人罢了。 16、流过泪的眼睛，更明亮。滴过血的心灵，更坚强。 17、有时候，会有种莫名的无助，去又不知道为什么。 18、忘了从什么时候开始，习惯了夜生活的有条不紊，不知道从什么时候开始，害怕了一个人的夜晚。 19、时光飞逝，停在哪里休息，哪里都有真情体现，我们不能害怕欺骗，把自己的热情藏在心里。 20、亲爱的自己，不要抓住回忆不放，断了线的风筝，只能让它飞，放过它，更是放过自己。不管现实多惨不忍睹你都要固执相信这只是黎明前短暂的黑暗而已。
广州市直M M为大家解答本次广州市考相关问题管理提醒：本帖被the9sun 设置为精华(2011-10-26) 09年考公进入广州市直MM，混迹qzzn多年终上岸，目前在市直组织人事部门任职，直接参与招考各个环节。 此次我所属的单位也有参加招考，看到坛子上很多xdjm挺多疑问，为回报论坛，特为此次市考的面试、资格审查、政审等问题，为大家解答。知无不言 关于大家关心的几个问题，在此一并解答一下 一、资格审查需要准备哪些材料？（所有资料都要带原件、复印件） 1. 应届毕业生： 必须带上：身份证+学生证+普通高校毕业生就业推荐表+暂缓协议 其他备用：户口本、计划生育保证书（如果没带就当场写） 2. 社会人员： 必须带上：身份证+户口簿+学历证书+学位证书。 2年经验人员必须带劳动合同；如果没有劳动合同，带上单位工作经历证明+社保记录盖章；如果没有合同又没有证明，带上社保记录盖章 社会人员：带上单位工作经历证明备用 3. 在国有单位工作，必须带单位同意报考证明。 在事业单位工作的事业编，必须带单位同意报考证明。
在事业单位的派遣或者合同制员工，不用带同意报考证明。 二、面试环节需要注意哪些： 大家都知道的就不说了，说几个具体的细节 1.考官一般有10-12人。正面面对而坐，面试时间一个人15-20分钟，4-5个题 2. 面试一般有主考官念题，只念一遍（所以要挺清楚） 3. 考试面前一般都有一张白纸和一只笔。因此允许短时间的思考和列提纲（不过建议不要思考时间太长，15-20秒则ok） 4. 面试着装：自己穿着觉着舒服的正装。现在夏天，男生适合短袖衬衣+西裤，建议不打领带；女生适合套裙或者短袖衬衣+西裤 5. 面试之后，一般会要求到其他办公室回避一下，大概过几分钟，就会把面试成绩当场宣布给你。等面试人员基本结束后，就可以大致算出各自排名了。 三、体检 1. 体检一般是面试后两三天就开始，广州市考有几个定点体检医院，一般是各单位就近选择 2. 体检每个项目由医生填写具体记录和项目结论“合格”或“不合格”。如果有单项不合格，一般是不会录用的。医院也是根据公务员录用的要求来填写是否合格 3. 体检一般第二天或第三天招考单位即可知道结果。不联系考生则为通过了，如果联系考生 可能就是要复检 四、政审 1. 政审一般在体检后大概10-15天进行
从你的全世界路过 From your world through 2019-03-05 我希望有个如你一般的人 如山间清爽的风 如古城温暖的光 从清晨到夜晚 由山野到书房 只要最后是你 就好 …………①………… 词：何星烁/刘流 曲：何星烁/刘流 女：让我从何提起 日子充实空虚 空气弥漫孤寂 美好时光与你 相遇在意和伤害成正比 逞强太无底气 为爱改变自己 为你与世为敌
生命重拾意义 不甘我的世界 和你阴差阳错轻描淡写只成一道风景 念白：从你的全世界路过你就只路过了一次 却成了我的全部世界RapStar—— 男：每晚坐在电台 用熟悉的声音陪伴 你坐在我的身旁 却无暇我的呐喊 是你的离开让我成为 全台的笑柄 你说你想爬的更高 去看看那的风景 我放你走 忍痛撒开了你的双手 我举牌上街游走 我甘愿为你出糗 我为你付出一切 因为我曾对你承诺
没错我叫陈沫 最后却只能选择沉默你抱着我说 你把爱情献给了青春你说合适大于爱情结束了这段缘分 怪我太过幼稚 是我不够成熟 以后的路陪不了了小容你要幸福 我的猪头兄弟 你丫差不多就回来吧我明白你的绝望 我也明白你很爱她做她爱吃的食物 去看她看过的风景她已经走了兄弟 拜托你要醒醒 你给了他你的一切那不是她想要的 你说没她你不活了你这不开玩笑嘛
她和你相爱因为感动和你的陪伴 但她因为现实走了 请不要再去遗憾 女：为爱改变自己 为你与世为敌 生命重拾意义 不甘我的世界和你 阴差阳错轻描淡写 只成一道风景 男：荔枝姑娘不要难过要相信十八还在 那小子真的命大 他很快就会回来 我真的羡慕你们那 童话般的爱情 祝你们永远幸福平安仪器不再报警 抱歉了幺鸡 让你等了我太久太久我不会再让你路过 我会占为己有
操作系统 1、计算机的硬件基本上由哪五大部分组成？ 答：运算器、控制器、存储器、输入设备、输出设备。 2、运算器都可对数据进行哪两种运算？ 答：算术运算和逻辑运算。 3、CAD、CAM、CAT、CAI都代表什么？ 答：1、计算机辅助设计（CAD） 2、计算机辅助制造（CAM） 3、计算机辅助测试（CAT） 4、计算机辅助教学（CAI） 4、数据处理是指对数据的（收集）、（存储）、（加工）、（分析）、（传送）的全过程。 5、程序性语言分为（机器语言）、（汇编语言）、（高级语言）三类。 6、能举出哪些是高级语言、哪些是低级语言？ 低级语言：汇编语言 高级语言：basic . cobol . c. foxbase等 7、操作系统可分为（批处理操作系统）、（分时操作系统）、（实时操作系统）三种操作系统。 8、解释型程序和编译型程序有什么不同？哪种程序产生目标程序？编译程序产生目标程序 9、DBMS是什么的？
答：DBMS 是数据库管理系统。 10、计算机系统由（硬件）系统、（软件）系统两部份组成。 11、软件系统分为（系统）软件、（应用）软件两部分。 12、操作系统的特征：（并发）、（资源共享）、（虚拟）、（异步）。 13、没有任何软件支持的计算机称为（裸机）。 14、操作系统的五大功能（处理机管理）、（设备管理）、（存储器管理）、（文件管理）、（提供友好的用户接口）。 15、操作系统发展的过程：（无操作系统）、（单道批处理系统）、（多道批处理系统）、（分时系统）、（实时系统）、（网络操作系统）、（分布式系统）。 16、Spooling系统是（批处理）系统。 17、批处理系统有两大特点（自动性）、（顺序性）。 18、批处理系统追求的目标是什么？不断提高系统资源利用率，提高系统吞吐量。 19、分时系统的特点（多路性）、（独立性）、（及时性）、（交互性）。 20、分时系统的主要目标？系统对用户的响应时间。 21、实时系统分为哪两类？并能举出这两类的例子。飞机飞行、弹道发射、预定飞机票、查询航班都是什么系统？ 22、实时系统的主要特点是什么？（可靠性）、（多路性）、（独立性）、（及时性）、（交互性）。 23、个人计算机上的操作系统是（单用户多任务）操作系统。 24、计算机的应用领域包括什么？