1. Hello Saravana,
Personal certificate request - The binary file that is used to send to a
Certificate Authority to create a personal certificate. Sent to the trust
authority.
Personal Certificate - This is the certificate assigned to this hostname either
client or server. It is used on the handshake to identify the server and used
to verify it is trusted
A personal certificate represents the identity of the end point and contains a
public and private key for signing/encrypting data.
Signer Certificate - is the certificate that is used to verify the personal
certificate is from a valid trust authority.
A signer certificate represents a certificate and public key associated with
some personal certificate. The purpose of the signer certificate is to verify
personal certificates. By accepting the signer certificate into an end point's
trust store, you are allowing the owner of the private key to establish
connections with this end point; that is, the signer certificate explicitly
trusts connections made to or by the owner of the associated personal
certificate. The signer certificate is typically made completely public by the
owner of the personal certificate, but it's up to the receiving entity to
determine if it is a trusted signer prior to adding it to the trust store.
Note: this can be a chain of certificates where they may be a series of
intermediate certificates that lead back to root certificate. The root is
identified by issued to and issued by are the same ceritficate.
