Simple meaning is Post Office Protocol . Standard port: 110
POP version 3 is being the current standard for e-mail retrieval. POP3 is used by most webmail services, such as Gmail and Yahoo
Define in RFC 1939
Index :
- POP3
- Using POP3
It active in the Application layer and used by e-mail client to retrieve e-mail from remote server over TCP/IP connection.
- POP and IMAP are two most prevalent Internet standard protocols for e-mail retrieval.
- POP3 server listen in port 110
- POP3 client will make a TCP connection to POP3 server to use services . Immediately, server will say hello to client
- Connection will keep alive until receive quit command or break connection
- Reply have two formatting:
- +OK
- -ERR
Using POP3:
USER <user_ID>
Send user ID for mail server to login
PASS <password>
Send password for mail server to certify account
STAT
Request to reply statistic e-mails in POP server
Syntax:
+OK #msg #bytes
#msg: counting email on server
#bytes: counting bytes for emails
LIST
Show list email on server
Information will be receive more time
+OK 3 messages
1 1205
2 305
3 344400
RETR #msg
Get email #msg
RETR 2
TOP #msg #line
Show the title of email #msg and #line lines of content of that mail
TOP 1 0
Is show title email 1 and don’t need context
DELE #msg
Checked email delete
Email just clear until client send request QUIT
RSET
Clear checked to delete email
QUIT
End session
Server for example
Pop.mail.yahoo.com 110
write by : hotdream1990
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