Applications

The Web

• Client-Server Architecture

HTTP: Hyper Text Transfer Protocol

• Requirements
• Format
• Methods
• GET
• HEAD
• POST
• Interaction with TCP

E-mail

Overview

• Addresses:

string@DNSNAME
• Message Format
• RFC822
• MIME: Multipurpose Internet Mail Extensions
• Typical Setup


• Procedure

Protocols

• SMTP: Simple Mail Transfer Protocol
• Commands
• HELO
• MAIL
• RCPT
• DATA
• RSET
• NOOP
• QUIT
• HELP
• VRFY
• EXPN
• ESMTP: Extended SMTP
• POP: Post Office Protocol
• Commands
• STAT
• LIST
• RETR
• DELE
• RSET
• QUIT