http

uses TCP

  • client initiates TCP connection (creates socket) to server, port 80
  • server accepts TCP connection from client
  • http messages exchanged between browser & web server
  • tcp connection closed
  • server maintains no info about past client request (as part of http protocol)

types

non-persistent http

at most 1 object sent over TCP, connection then closed. Downloading multiple object required multiple connections.

persistent http

multiple objects can be sent over a single tcp connection between client, server

Structure

  • status line
  • headers
  • data

cookies