Information Security Services PDF

There are various services of information security which are as follows − Message Confidentiality − Message confidentiality or privacy defines that the sender and the receiver expect confidentiality. The transmitted message should make sense to only the predetermined receiver. When a user connects...

There are various services of information security which are as follows − Message Confidentiality − Message confidentiality or privacy defines that the sender and the receiver expect confidentiality. The transmitted message should make sense to only the predetermined receiver. When a user connects with the bank, they predict that the communication is completely confidential. Message Integrity − Message integrity defines that the data should appear at the receiver accurately as they were sent. There should be no changes for the duration of the transmission, neither by chance nor maliciously. As increasingly monetary exchanges appear over the web, integrity is crucial. Message Authentication − Message authentication is a service that furthers message integrity. In message authentication the receiver is required to be certain of the sender's identity and that an imposter has not sent the message. Message Nonrepudiation − Message nonrepudiation defines that a sender should not be able to deny sending a message that they send. The burden of data falls on the receiver. Entity Authentication − In entity authentication, the entity or user is documented previous to access to the system resources. For instance, a student who is required to access the university resources is required to be authenticated during the logging phase. This is to assure the interests of the university and the student. Types Of Cryptography 1. Symmetric Key Cryptography It is an encryption system where the sender and receiver of a message use a single common key to encrypt and decrypt messages. Symmetric Key cryptography is faster and simpler but the problem is that the sender and receiver have to somehow exchange keys securely. The most popular symmetric key cryptography systems are Data Encryption Systems (DES) and Advanced Encryption Systems (AES). 2.Asymmetric Key Cryptography In Asymmetric Key Cryptography, a pair of keys is used to encrypt and decrypt information. A receiver’s public key is used for encryption and a receiver’s private key is used for decryption. Public keys and Private keys are different. Even if the public key is known by everyone the intended receiver can only decode it because he alone knows his private key. The most popular asymmetric key cryptography algorithm is the RSA algorithm.