POSTFIX without IMAP/POP3
 

I have installed Postfix with LDAP, Dovecot IMAP/POP3 Server on RHEL 5.5
whether Postfix without IMAP/POP3 server is possible??
Any other mail retrieval from remote?

Postfix is an MTA, it moves mail from place to place - so yes you can have postfix by itself, but I don't think that's what you mean. Are you asking if there are other protocols for mail delivery ?

Yes,protocols to retrieve mail other than IMAP and POP3.

As kpb said, "Postfix is an MTA, it moves mail from place to place". Postfix, an MTA does not deal with POP and IMAP, nor does it even care about them. Postfix will handle delivery, to a mailbox or maildir, or other method as you configure in the master.cf file, for domains that it believes it is the recipient domain. How you handle retrieving the mail after that is up to you, but POP and IMAP are them most common protocols.

you could possibly have a local user on your server and let FTP to login to it's directory (chroot) and then browse through Maildir/new , Maildir/cur directories and retreive the files whatever the names they have and then rename them to .eml to open it in some (windows) mail client (like Outlook express ...). Tested, working.

As noway2 said, pop and imap are the most common protocols ... you could also try a web based solution like squirrelmail.