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Suppose that you want to send an e-mail to someone and you want to ensure that no one else can read the message. You must change the message in some way so that anonymous intruders cannot read its content.
In cryptographic terminology, the unaltered message is called
plaintext. If the contents of a message is altered in such a way that the meaning is hidden from others, the file is considered to be encrypted. The process of encrypting information or converting information to an unreadable form is called encryption. The encrypted message is called the ciphertext.
The process of retrieving the plaintext from the ciphertext is called
decryption. Encryption and Decryption usually make use of a key. It is hoped that a message cannot be decrypted unless the recipient of the message has the proper key and knows the method by which the message was encrypted. The method used to encrypt or decrypt the message is sometimes referred to as the coding method or simply the encoding.
Cryptography is the art or science of keeping communications secret. Cryptanalysis
is the art of breaking encrypted messages, i.e. retrieving the plaintext by analyzing the ciphertext without knowledge of the key. People who practice cryptography are called cryptographers;
cryptanalysts being individuals who practice cryptanalysis.
Cryptography deals with all aspects of making information secure (secure messaging); verifying that the correct people have permission to use, send, encrypt, or decrypt a message (authentication); veryfying that the sender of a message is not an imposter (digital signatures); making sure that web enabled transactions are secure so that electronic money is properly exchanged; and other applications like smart cards and securing files. Cryptology is the branch of mathematics that studies the mathematical foundations of cryptographic methods.
Cryptographic Algorithms
The algorithm used in encryption and decryption is called a cipher. No method is better than the cipher or algorithm it uses to encrypt messages or files. Cryptographic methods rely on the secrecy of the algorithms, the ability of the algorithm to scramble the plaintext sufficiently to resist cryptanalysis, and a secret key to protect the encrypted message in case the algorithm is discovered. All modern algorithms use a key to control encryption and decryption. Ideally, it is hoped that a message can be decrypted only with the proper key.
There are two classes of key-based encryption algorithms, symmetric (or secret key) and
asymmetric (or public key) algorithms. The difference is that symmetric algorithms use the same key for encryption and decryption (or the decryption key is easily derived from the encryption key), whereas asymmetric algorithms use a different key for encryption and decryption, and the decryption key cannot be derived from the encryption key.
Symmetric algorithms can be divided into stream ciphers and block ciphers. Stream ciphers can encrypt a single bit of plaintext at a time, whereas block ciphers take a number of bits (typically 128 bits in modern ciphers), and operate on them as a single unit to encrypt a block of text.
Asymmetric ciphers also called public-key algorithms or generally public-key cryptography, permit the encryption key to be public, that is, it can even be published in a newspaper or in a web dictionary. This allows anyone to send an encrypted message to a targeted recipent by encrypting the message with the recipients key. Supposedly, only the proper recipient who knows the decryption key can decrypt the message. The encryption key is also called the public key and the decryption key is called the private (or secret) key.
Modern cryptographic algorithms are no longer pencil-and-paper ciphers. Strong cryptographic algorithms are designed to be executed by computers or specialized hardware devices. In most applications, cryptography is done in computer software like Dynacrypt® Version 4.0.
Generally, symmetric algorithms are much faster to execute on a computer than asymmetric ones. In practice they are often used together, so that a public-key algorithm is used to encrypt a randomly generated encryption key, and the random key is used to encrypt the actual message using a symmetric algorithm. This is sometimes called hybrid encryption.
Descriptions of many good cryptographic algorithms are widely and publicly
available from any major bookstore, scientific library, patent office, or on the Internet. The most studied symmetric cipher was the Data Encryption Standard or DES; the Advanced Encryption Standard or AES replaced it in the first quarter of 2001 as the new encryption standard. RSA is probably the best known asymmetric encryption algorithm.
DES and AES were sponsored by the Federal Government (National Institute for Standards Testing (NIST)) as standards to be used for encryption and decryption. DES was considered not secure with its weak 56-bit key and needed to be replaced with a stronger cipher. AES was voted by a committee to replace DES. It is an algorithm proposed by Joan Daemen and Vincent Rijmen and adopted by the Federal Government on October 2, 2000 as the new standard for encrypting information. The Algorithm is called Rijndael, pronounced "rain doll".
The most important questions to ask are:
- Given that AES is highly regarded by the Federal Government, why is it public and available to our enemies?
- What disqualifies AES as being able to securely encrypt Classified, Secret, or Top Secret information?
- Can you trust the Federal Government and the National Security Agency (NSA) to propose a standard to you that is secure, meaning they cannot break it whenever they want to?
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Secure communications is an issue of paramount concern to public and private America. The Federal Bureau of Investigations (FBI) along with the NSA and CIA are monitoring all communications in this country whether they are Internet, cellular telephone, regular telephone, books, newspapers, television, or any kind of communication broadcasts. The FBI has the Carnivore program to monitor and listen in on all Internet communications. This is why you need a secure encryption method that they cannot break like Dynacrypt® Version 4.0.
Many encryption schemes have been proposed with the intent of securing
communications over the Internet. Some of these methods are:
| Method |
Author |
Key Size |
Block Size |
| RSA |
Rivest, Shamir, Adelman |
Variable bit modulus |
Variable |
| DES |
IBM/NSA |
56-bit |
64-bit |
| Triple-DES |
IBM/NSA |
168-bit |
64-bit |
| Blowfish |
Bruce Schneier |
up to 448-bit |
64-bit |
| CAST |
Adams & Tavares |
64-bit |
64-bit |
| IDEA |
Lai & Massey |
128-bit |
64-bit |
| MDC/SHA |
Peter Gutmann |
512-bit |
160-bit |
| RC2, RC5 |
Ron Rivest |
Variable key size |
64-bit |
| RC4 |
Ron Rivest |
Variable key size |
Stream Cipher |
| RC5-w/r/b |
Ron Rivest |
Variable key size |
Variable block size |
| 3-Way |
Joan Daemen |
96-bit |
96-bit |
| Skipjack |
NSA |
80-bit |
64-bit |
| GOST |
Former Soviet Union Government |
64-bit |
256-bit |
| Elliptic Curve |
Koblitz & Miller |
Variable bit modulus |
Variable |
| AES (Rijndael) |
Daemen & Rijmen |
128, 192, 256-bit |
128 to 256 in steps of 32 |
These methods with the exception of RSA and Elliptic Curve are secret key, symmetric cryptographic methods. Secret key, symmetric systems are faster data execution methods than the public key, private key, asymmetric method of RSA. However, RSA and especially the Elliptic Curve CryptoSystem may offer the advantage of increased security, if very large prime numbers or a very large bit modulus is used.
The algorithms used in all of these systems are public information. They rely upon the assumption that it will take a long time before computers can break the code using a brute force method or that the necessary computing power is too expensive to build. In the case of RSA, it is assumed that it is very difficult to factor two large prime numbers that is necessary to break the public key, private key method of RSA. Although it is not necessary to factor two large primes to decrypt RSA, a judicious choice of public and private keys will make it virtually impossible to break by brute force.
While these methods may offer some security with the current state of computers, they are not without security risks. The authors of RSA issued a $10,000 challenge to anyone who could break the DES 56-bit encryption scheme. On June 18, 1997, thousands of Internet users and computer hackers combined their efforts and in only four months cracked the DES 56-bit encryption scheme. RSA's next DES challenge (RSA DES-II-1) began on Tuesday, January 13, 1998. Distributed Net discovered the key about 39 days later. RSA's most recent challenge (RSA DES-II-2) before DES was deemed useless began on Monday, July 13, 1998. The key was discovered on Wednesday, July 15! The Electronic Frontier Foundation using a homemade DES Cracker machine costing about $250,000 found the key.
Other encryption schemes have not been attacked like DES. This is because many computer experts felt that the government had purposely crippled IBM's 112-bit encryption scheme to a breakable 56-bit Data Encryption Standard (DES). The government thought that with a 56-bit scheme producing 7.205759403793 x 10e16 (72 quadrillion) possible keys, it could convince the public that DES would be difficult to break.
A message encrypted with RC5 using a 64-bit key was broken by Distributed.net.
It is generally thought that brute force attacks are impractical and a waste of time. Most so-called experts believe that computers will not be fast enough to search through the required number of keys to break the cryptographic system. These ideas are backed up by theoretical physicists making predictions on how much energy it will take for a computer to break say a 128-bit cryptographic system. The so-called Von Neumann-Landauer Limit implied by the laws of physics sets a lower limit on the energy required to perform a computation. according to the Von Neumann-Landauer Limit theory, to search through the possible values for a 128-bit key (ignoring any computing energy to check the results), one would need at a minimum a 10 gigawatts device running continuously for 100 years. Ten (10)gigawatts is approximately eight (8) large, dedicated nuclear reactors. This theory and its calculations are based on old computer technology with no forethought for modern computing. It is a ridiculous proposition but one that people who are using inferior schemes love to hear.
What these experts are doing are showing off their ignorance. Today we have computers with Central Processing Units (CPUs) that have millions of cores and operating speeds in the GHz range. On the horizon are Quantum computers.
Super Computing Threats
Because modern-day encryption schemes and their algorithms are all public information and have such small key sizes compared to Dynacrypt®, it is just a matter of time before computers are capable of breaking any of these schemes in a short period of time. Current computing technology such as the Cray XT5 Jaguar, which is located at the Department of Energy’s Oak Ridge Leadership Computing Facility, posted a 1.75 petaflops performance speed running the LINPACK benchmark. Jaguar roared ahead with new processors bringing the theoretical peak capability to 2.3 petaflops with nearly a quarter of a million cores. One petaflop is equal to one quadrillion or 10 raised to the power 15 floating point calculations per second. DES can be broken by Jaguar in less than 36 seconds. Jaguar was replaced as the fastest supercomputer by the Tianhe-1A supercomputer built by the National University of Defense Technology (NUDT) in China in November of 2010. The Tianhe-1A supercomputer posted a 2.6 petaflops performance in the LINPACK benchmark and can break DES in less than 28 seconds. The Tianhe-1A supercomputer is built using 14,336 Xeon X5670 processors, 7,168 NVIDIA Tesla M2050 general purpose graphics processing units (GPUs), and 2,048 NUDT FT1000 heterogeneous processors. The Tianhe-1A supercomputer was replaced as the fastest supercomputer by Japan’s K Computer located at the RIKEN Advanced Institute for Computational Science in Kobe, Japan. It uses 640,000 CPU cores to achieve a speed of eight (8) Petaflops which could break DES in less than nine (9) seconds.
IBM and others are building supercomputers that will break the exaflops barrier by 2019. These new supercomputers will be posting speeds in the exaflops range or one quintillion or 1018 floating point operations per second. Also, these supercomputer performances are what is being posted and made public. With special purpose computers that are specifically designed to attack a specific algorithm like AES, much faster results can be obtained. In particular, since encryption algorithms are mainly integer operations and do not involve the use of real or floating point numbers, these super computers and special purpose computers can probably break DES in less than 1 second. When 56 bits is looked at in the right way, one would find that this represents only seven (7) readable characters. To permutate through all variations of seven (7) characters for a key could be done in less than a microsecond.
Do not believe that NSA cannot crack AES anytime that they want to, especially with backdoors implemented in the encryption program. They would not be pushing the AES method unless they could crack it. It is cryptographically stupid to push and promote a publicly available cryptographic standard like AES as being secure. This would mean that our enemies could get the algorithm, get their software developers to program it and produce a software program to secure their communications so that our Government could not read and decipher their messages. It should not seem reasonable to an intelligent person that our Government would allow such a scenario to exist. In readable text, AES 256-bit key represents only 32 characters while Dynacrypt® represents 125,000 characters plus 125,000 64-bit integers. Since an AES key is only 32 characters, it could be placed in the encrypted file at a known location and anyone that knows this location could retrieve the key and decrypt the file.
Because AES is publicly available as an open source algorithm, it must not pose a threat if implemented. To further misdirect people, the Government imposes export restrictions on encryption software. For example, it is illegal to export software that contains encryption strengths greater than 64-bits, implying that the Government can only crack algorithms with encryption strengths of 64-bits or less.
It should be kept in mind that we are talking about single supercomputers. Thousands of supercomputers or special purpose supercomputers may be effective as a group by splitting up the search space among the computers and possibly finding the right key for algorithms like AES in a brute-force attack.
Quantum Computing Challenge
Quantum computers propose to solve many problems like those that many cryptosystems are based on in a very short period of time. Number factoring and inverting functions are two (2) of the so-called hard problems that quantum computers are designed to solve quite easily.
Quantum computers using Shor's algorithm will make the RSA Public Key-Private Key encryption method, Diffie-Hellman and Elliptic Curve Cryptography obsolete and its pure computing power using Grover’s algorithm may make the current 256-bit symmetric algorithms obsolete. D-Wave Systems, Inc., a Canadian based company is working with Google and NASA and claims that they will have a working 128-qubit quantum computer by the end of 2011. A qubit is a quantum bit that all quantum computers are based on.
Dynacrypt® Version 4.0 is the only answer to maintain the security of smart grids, medical records, banking accounts and transactions, and your personal and private data even with the advances in computing power: conventional or quantum. It is the only cryptosystem that meets the Quantum Computer challenge.
Considerations
Another important issue of interest is that security thieves have learned that instead of trying to break an encryption scheme by brute force, it is better to find out what the receiver of an encrypted message is trying to do to the message by monitoring their key strokes through a Keylogger and getting remote access to the user's computer. These thieves send a message to a receiver using the appropriate authentication, digital signature, and public key. Next, they monitor what the receiver is trying to do to the cipher text to decrypt it. Monitoring the computer operations of the receiver gives the thief important information about the receiver's private key or encryption keys.
There are several important facts that have been learned about modern day cryptography that are of interest for developing new encryption schemes for securing data transmissions over the Internet:
- Send only encrypted messages that have been encrypted offline.
- Decrypt messages while offline.
- For secure transmissions, do not use a standard proposed by the government for public use.
- The encryption scheme should have the potential to use an infinite number of keys to produce an infinite number of bits, if necessary.
- The encryption scheme should optimize speed and security.
- The encryption scheme should dynamically allocate sub-keys, Pre-Defined Keys, and other variables per a designated number of bits.
- Ciphertexts produced from the same plaintext using the same secret key should be significantly different from one another with no correlation among the ciphertexts.
- The proposed encryption scheme should score high on all measures of cryptographic strength.
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