Interested to Buy Any Domain ? << Click Here >> for more details...
Answer Posted / ramkumar
Suppose Alice wants to find Bob's public key. There are
several possible ways of doing this. She could call him up
and ask him to send his public key via e-mail. She could
request it via e-mail, exchange it in person, as well as
many other ways. Since the public key is public knowledge,
there is no need to encrypt it while transferring it,
though one should verify the authenticity of a public key.
A mischievous third party could intercept the transmission,
replace Bob's key with his or her own and thereby be able
intercept and decrypt messages that are sent from Alice to
Bob and encrypted using the ``fake'' public key. For this
reason one should personally verify the key (for example,
this can be done by computing a hash of the key and
verifying it with Bob over the phone) or rely on certifying
authorities (see Question 4.1.3.12 for more information on
certifying authorities). Certifying authorities may provide
directory services; if Bob works for company Z, Alice could
look in the directory kept by Z's certifying authority.
Today, full-fledged directories are emerging, serving as on-
line white or yellow pages. Along with ITU-T X.509
standards (see Question 5.3.2), most directories contain
certificates as well as public keys; the presence of
certificates lower the directories' security needs.
| Is This Answer Correct ? | 0 Yes | 0 No |
Post New Answer View All Answers
What are the advantages of public-key cryptography compared with secret-key cryptography?
Does encryption of connection strings in web.config file possible? How?
A company wants to transmit data over the telephone, but it is concerned that its phones may be tapped. All of its data is transmitted as four-digit integers. It has asked you to write a program that will encrypt its data so that the data may be transmitted more securely. Your script should read a four digit integer entered by the user in a prompt dialog and encrypt it as follows: Replace each digit by (the sum of that digit plus 7) modulus 10. Then swap the first digit with the third, and swap the second digit with the fourth. Then output XHTML text that displays the encrypted integer.
What is public key encryption?
What is luc?
What is merkles tree signature scheme?
Is there a limit on the file size or on the number of encrypted files?
What is the mceliece cryptosystem?
What is cryptographic synchronisation?
What is key management ?
What is the difference between Kryptel and Silver Key?
How Encoding is different from Encryption?
What is probabilistic encryption?
what are some of the current encryption schemes?
What is the difference between a message authentication code (MAC) and a one-way hash?
