Post Office Protocol Version 3

Post Office Protocol ( POP3 ) Version 3

This protocol is used to retrieve mails from POP3 Server. The following commands were used in this protocol, this is an upper layer of TCP/IP. The socket number used for POP3 is 110.

              USER username
              PASS Password
              STAT
              LIST
              TOP   MessageNumber Numberof Lines ( Eg., TOP 3 10 )
              RETR MessageNumber
              DELE MessageNumber
              QUIT

A sequence of the data exchange is shown below, Assume you are the user of "creaf.com" with userid as "tony" and password is "paly31re", the flow is,

Telnet to creaf.com at port number 110

S: Send from the client R: Received to the Client

          R: +OK QPOP (version 2.53) at md3.vsnl.net.in starting.
          S: USER tony
          R: +OK Password required for tony.
          S: PASS paly31re
          R: +OK tony has 6 messages (17564 octets).
          S: STAT
          R: +OK 6 17564
          S: LIST
          R: +OK 6 messages (17564 octets)
          R: 1 2982
          R: 2 3925
          R: 3 2171
          R: 4 4403
          R: 5 1488
          R: 6 2595
          R: .
          S: RETR 1
          R: +OK 2982 octets
          R: // You will receive the contents of first mail
          R: .
          S: RETR 2
          R: +OK 3925 octets
          R: second mail contents ...
          R: .
          S: TOP 3 10
          R: +OK 4123 octets
          R: First 10 Lines of the contents of Message 3
          R: .
          S: DELE 1
          R: +OK Message 1 has been deleted.
          S: DELE 2
          R: +OK Message 2 has been deleted.
          S: QUIT
          R:+OK Pop server at md3.vsnl.net.in signing off.

Like to know more about POP3, move to http://internic.net

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