Security Services

Most of you will have a habit of sending a mail or message to your friend using internet. Having you ever thought about the security of that particular message? How much confident are you that the message is read only by your friend and its released to others? The answers are that OSI works for you in order to safe guard the message. OSI is a protocol (abstract model of networking).

The security services provided by OSI are

• Access control

• Data integrity

• Authentication

• Confidentiality

Access control:This service will prevent an unauthorized user using our resources

Data integrity: This service will check weather the data send by the sender is same as that of received message.For example if a person A sends a message that" prevent the bomb blast going to be held on by coming Monday" to B, Say E to be other person who will interrupt the message and change it to be" prevent the bomb blast going to be held on by coming Tuesday".Here data integrity will play its roll in order to prevent E to alter the message.

Authentication:This service will check wheatear a message came from a authenticated person. For example B will receive a message That " I am your friend A, I need a help from you". At this stage B will having a doubt wheatear that is A or some one else on behalf of A.At this stage Authentication gives us a signature method ie A has its own signature, when it sends a message to B, it will sign the message with its sign. Just like your inbox mail from your friends mail id. Looking at the Id of your friend you will think that message is send by your friend.

Confidentiality:This service will check wheatear a message is kept confident. For example have message as " we are going to attack our enemy country be ready". This message must be passed confidentiality, It don't need the sender information.