Network and Internet Security Essay Example | Topics and Well Written Essays - 1500 words

Network and Internet Security - Essay Example This technique ensures that there is only one key which will be used – that is a secret key. Asymmetric encryption (Public key encryption) - requires the use of a two keys where one is a private key and the other is a public key which is known to a number of people. With that, these two keys (public and private keys) are used interchangeable to encrypt and decrypt messages. Hybrid encryption (single key and public key) – this technique used both the symmetric and asymmetric encryption techniques. It is important to note that, modern systems have been designed to be dynamic in terms of the encryption technique (s) that they are using. As a result; they can use both the symmetric and asymmetric encryption techniques interchangeably. Encryption by a shared secret: As the name suggests, two hosts can be in a position to exchange information through the use of a shared secret and/ or a secret key. This mechanism is characterised by the fact that the shared secret key is used to encrypt both the senders and the recipient’s messages. Based on that, this channel faces very high security risks since if the message is tapped or eavesdropped, the attacker can be in a position to use the shared secret key to either encrypt or decrypt the entire conversation. Based on that, data security is highly compromised. The other challenge faced with the shared secret key encryption is the fact that the higher the messages that are being sent on the communication channel by the hosts, their corresponding keys will also be increased. As a result, there will be too many keys being shared. Thirdly, due to the fact that it is a shared key, if the sender’s key is not known, decrypting the... Sessions keys are implemented using the following process description: If Host A, B and C want to communicate to each other; they have to set up an encrypted link among themselves. With that, if Host A wants to send an encrypted message to B and C, then A will have to provide its key that will be used by B and C in a bid to decrypt the ciphered message. This key exchange process requires the availability of a Key Distribution Centre (KDC) that is used to store the shared session keys. It is worthy to note that, this scheme totally depends on the KDC and if the KDC encounters any problems, then that will compromise on data security. With that stated, below are some of the challenges that may be faced by the KDC. First, if the KDC fails to store the session keys, then the hosts will not be in a position to encrypt and decrypt the messages. Secondly, if the number of keys grows then there is a need for a scalable KDC else it will fail to provide the keys. Thirdly, the KDC is not used fo r connection fewer protocols. Fourth, transporting the keys physically can be tedious. The above encryption techniques can be used in the following protocols and/ or products: Kerberos V4, Kerberos V5 and Secure Socket Layer (SSL). Kerberos is a network authentication protocol that is used in a bid to provide security for both the client and the server through the use of the secret-key cryptography. Kerberos also depends entirely on the KDC so as to ensure secure communication between the hosts.