SSL addresses the following important security considerations.
Authentication : During initial attempt to communicate with a web server over a secure connection, that server will present your web browser with a set of credentials in the form of a server certificate. The purpose of the certificate is to verify that the site is who and what it claims to be.
Confidentiality : When data is being passed between the client and the server on a network, third parties can view and intercept this data. SSL responses are encrypted so that the data cannot be deciphered by the third party and the data remains confidential.
Integrity : When data is being passed between the client and the server on a network, third parties can view and intercept this data. SSL helps guarantee that the data will not be modified in transit by that third party.
authentication over the internet is not really a concern for example, an administrator may simply want to ensure that data being transmitted and received by the server is private and cannot be snooped by anyone eavesdropping on the connection, that is only data privacy and integrity are important
A server certificate is a container that contains server's public key and other miscellaneous information
Web server must have an associated certificate for each external interface, or IP address, that accepts secure connections. This provides some kind of reasonable assurance that its owner is who you think it is
Commercial for Certificate Budget Required (Tentative figure by Vendors) http://www.verisign.com/ssl/buy-ssl-certificates/secure-site-services/index.html $ 1499/Year Verisign 1 Remarks Budget Required Name of the Vendors Sr. No.