Shopping on line can be easy, simple and save you lots of money. It can also take a lot of your time, frustrate you, and result in unwanted purchases. Now the same can be said for regular high street shopping, but with the vast opportunity presented by the Internet it will pay you to spend a few minutes reading this and understanding how to better optimize your Rc2 shopping experience:
1. Compare - without doubt the biggest advantage that the Rc2 offers shoppers today is the ability to compare thousands of Rc2 at a time. This is a great thing, but not necessarily all the time! Too much can be daunting at times so take advantage of the great comparison sites and where possible let them do the hard work for you.
2. Research - if it has been said it will be on the internet. Ignorance is no longer a justifiable reason for buying the wrong thing. Take the time to research in detail everything that you could possible want to know about
3. Testimonials - don't know anybody that has bought a Rc2? Wrong! If the Rc2 is good the internet will let you know. Use the Internet as a friend and get testimonials before you buy.
4. Questions - Got a question about Rc2 then search the Forums, FAQ's, Blogs etc. Don't be afraid to ask .....
5. Reputation - Never heard of the company selling Rc2? Don't worry, no reason why you should know every company in the world, but you know someone that does! Use the internet to find out what people are saying about Rc2 and build up a picture of their reputation for sales, returns, customer service, delivery etc.
6. Returns - still worried that even after all of the above your Rc2 wont be what you want? Check out the returns policy. There is so much competition now that someone, somewhere is bound to offer the terms that you are comfortable with.
7. Feedback - happy with your Rc2 then let people know, after all you are depending on others people input in your buying decision, so why not give a little back.
8. Security - check for the yellow padlock on the Rc2 site before you buy, and the s after http:/ /i.e. https:// = a secure site
9. Contact - got a question about Rc2, or want to leave a comment then check out the sites contact page. Reputable companies have them and respond.
10. Payment - ready to pay for your Rc2, then use your credit card or PayPal! Be aware of companies that don't accept them, there may be genuine reasons but given the huge amount of choice you have when buying online there is no reason at all not to buy via credit card or PayPal.
{{Infobox block cipher| name = RC2| image = | caption = The MIX transformation of RC2; four of these comprise a MIXING round| designers =
Ron Rivest, designed in [1987| rounds = 16 of type MIXING, 2 of type MASHING| cryptanalysis = A [related-key attack is possible requiring 234 chosen plaintexts (Kelsey et al, 1997).-->
In
cryptography,
RC2 is a block cipher designed by
Ron Rivest in 1987. "RC" stands for "Ron's Code" or "Rivest Cipher"; other ciphers designed by Rivest include
RC4 (cipher), RC5 and RC6.
The development of RC2 was sponsored by
Lotus Software, who were seeking a custom
cipher that, after evaluation by the
NSA, could be exported as part of their Lotus Notes software. The
NSA suggested a couple of changes, which Rivest incorporated. After further negotiations, the cipher was approved for export in 1989. Along with RC4, RC2 with a 40-bit encryption key size was treated favourably under US
Export of cryptography.
Initially, the details of the algorithm were kept secret — proprietary to
RSA Security — but on 29th January,
1996, source code for RC2 was anonymously posted to the Internet on the
Usenet forum,
sci.crypt. A similar disclosure had occurred earlier with RC4. It is unclear whether the poster had access to the specifications or whether it had been
reverse engineering.
RC2 is a block size (cryptography) cipher with a variable size key (cryptography). Its 18 rounds are arranged as a source-heavy
Feistel network, with 16 rounds of one type (
MIXING) punctuated by two rounds of another type (
MASHING). A MIXING round consists of four applications of the MIX transformation, as shown in the diagram.
RC2 is vulnerable to a related-key attack using 234 chosen plaintexts (Kelsey et al, 1997).
Sources
References
- Lars Knudsen, Vincent Rijmen, Ronald L. Rivest, Matt Robshaw: On the Design and Security of RC2. Fast Software Encryption 1998: 206–221
- John Kelsey (cryptanalyst), Bruce Schneier, David Wagner: Related-key cryptanalysis of 3-WAY, Biham-DES, CAST, DES-X, NewDES, RC2, and TEA. ICICS 1997: 233–246
External links
- RFC 2268 - A Description of the RC2(r) Encryption Algorithm
- RSA FAQ: What is RC2?
- sci.crypt posting revealing the RC2 algorithm
{{Infobox block cipher| name = RC2| image = | caption = The MIX transformation of RC2; four of these comprise a MIXING round| designers =
Ron Rivest, designed in [1987| rounds = 16 of type MIXING, 2 of type MASHING| cryptanalysis = A [related-key attack is possible requiring 234
chosen plaintexts (Kelsey et al, 1997).-->
In cryptography,
RC2 is a
block cipher designed by
Ron Rivest in 1987. "RC" stands for "Ron's Code" or "Rivest Cipher"; other ciphers designed by Rivest include
RC4 (cipher),
RC5 and
RC6.
The development of RC2 was sponsored by
Lotus Software, who were seeking a custom cipher that, after evaluation by the NSA, could be exported as part of their
Lotus Notes software. The NSA suggested a couple of changes, which Rivest incorporated. After further negotiations, the cipher was approved for export in
1989. Along with RC4, RC2 with a 40-bit encryption key size was treated favourably under US
Export of cryptography.
Initially, the details of the algorithm were kept secret — proprietary to RSA Security — but on
29th January,
1996, source code for RC2 was anonymously posted to the Internet on the
Usenet forum, sci.crypt. A similar disclosure had occurred earlier with RC4. It is unclear whether the poster had access to the specifications or whether it had been reverse engineering.
RC2 is a block size (cryptography) cipher with a variable size key (cryptography). Its 18 rounds are arranged as a source-heavy
Feistel network, with 16 rounds of one type (
MIXING) punctuated by two rounds of another type (
MASHING). A MIXING round consists of four applications of the MIX transformation, as shown in the diagram.
RC2 is vulnerable to a related-key attack using 234
chosen plaintexts (Kelsey et al, 1997).
Sources
- Steven Levy, Crypto: How the Code Rebels Beat the Government Saving Privacy in the Digital Age, ISBN 0-14-024432-8, 2001.
References
- Lars Knudsen, Vincent Rijmen, Ronald L. Rivest, Matt Robshaw: On the Design and Security of RC2. Fast Software Encryption 1998: 206–221
- John Kelsey (cryptanalyst), Bruce Schneier, David Wagner: Related-key cryptanalysis of 3-WAY, Biham-DES, CAST, DES-X, NewDES, RC2, and TEA. ICICS 1997: 233–246
External links
- RFC 2268 - A Description of the RC2(r) Encryption Algorithm
- RSA FAQ: What is RC2?
- sci.crypt posting revealing the RC2 algorithm
