Server Certificates:
Server Certificates are identitiy of a Server to presented by it during SSL handshake.
Typically they are issued by a certificate authority (CA) well known to client, The basis on which the certificate is issued is possession of some publicly known Identifier of that server, for Webserver its the Hostname of the server, which is used to reach server
Example:- http://blog.8zero2.in/
Server certifictae
Server Certificates Purpose
clearly mention by the x509 extension parameter
Certificate Key usage
1. Signing
2. Key Encipherment
Signing :- It means that the key in the certificate can be used to prove the Identity of the server mentioned in the CN of the cerificate , that is entity Authentication .
Key Encipherment :- It means the key in the in the ceritificate can be used to encrypt the session key ( symmetic key ) derived for the session
Client Certificate :-
Client certificates as the name indicates are used to identify a client or a user.
They are meant for authenticating the client to the server.
Purpose of holding a client certificate varies
It may represent possession of email address or Mac-address , usually mapped to the serial number of the certificate
Client Certificates Purpose
clearly mention by the x509 extension parameter
Certificate Key usage
1. Signing