Symmetric key cryptography:
It is also known as secret key
cryptography or private key cryptography. In this mechanism one key is used for
both encryption and decryption i.e. known as secret key. So there is a common
agreement should be done between sender and receiver before sending the
message. The most important thing is that the secret key should not be
disclosed to anyone else.
Asymmetric key cryptography:
It is also known as public key
cryptography, which deals with two different keys. Which are in a form of key
pair one key is used for encryption and
other corresponding key must be used for decryption.
No other key can decrypt the
message not even the sender’s key which was used for encryption can decrypt the
message so by this scheme every communicating party needs just a key pair for
communicating with any number of other communicating parties.
Suppose the sender (A) wants to
send a message to a receiver (B), then A and B each should have a private key
and a public key.
i.
A should remain his private key secret.
ii.
B should remain her private key secret.
iii.
A should inform B about the public key.
iv.
B should inform A about her public key.
Comparison between symmetric and asymmetric key:
|
Basis
|
Symmetric
|
Asymmetric
|
|
Key used for encryption
|
Same key is used for encryption and decryption
|
One key is used for encryption and other corresponding key is used
for decryption.
|
|
Speed of encryption & Decryption
|
Fast
|
Slow
|
|
Size of cipher text
|
Usually same or less than the plain text
|
More than the plain text
|
|
Number of keys required as compared to the number of participants in
message exchange
|
It equals
about the square of number of participants
|
Same as the
number of participants
|
|
Uses
|
It is used for encryption & decryption but cannot be used in
digital signature
|
It can be used for encryption decryption and digital signature also
|
|
Time consumption
|
Less
|
More
|
|
Complexity
|
Less
|
More
|
0 comments:
Post a Comment