Strength of cryptography
The strength of cryptography is determined as follows:
Either strong or weak.
It is measured in terms of the time and resources required to recover
the plaintext from the ciphertext.
Strong cryptography results in the ciphertext being difficult to
decipher without the possession of appropriate decoding tools and
high-end resources.
The cryptographic strength should not depend on the secrecy of the
cryptosystem but on the secrecy of the decryption key, as the attacker
knows the cryptosystem.
Requirement of cryptography
The requirements of cryptography are as follows:
U nauthorized individual(s) should not be able to gain access to
sensitive information, i.e., confidentiality. Cryptography prevents
criminals from stealing information online. The website with HTTPS
protocol enabled or when you log onto a WIFI hotspot or encrypt a
file, cryptography is at work.
Without the alteration being detected during storage or transit, i.e.,
integrity, the information between the sender and the recipient should
not be altered.
At a later stage, the sender of information cannot deny his or her
intentions in the transmission of the information ensured by non-
repudiation.
The sender and the receiver can confirm each other’s identity together
with the origin/ destination of information enabled by authentication.
The criteria of confidentiality, integrity, non-repudiation, and authentication
are met by the procedures and protocols of cryptosystems.
Further, cryptosystems include mathematical procedures, algorithms,
computer programs, choosing hard-to-guess passwords, thereby regulating
human behavior, together with logging off systems when not in use and not