The http protocol: more
http: TCP transport service:
client initiates TCP connection (creates socket) to server, port 80
server accepts TCP connection from client
http messages (application-layer protocol messages) exchanged between browser (http client) and Web server (http server)
server maintains no information about past client requests
Protocols that maintain “state” are complex!
- past history (state) must be maintained
- if server/client crashes, their views of “state” may be inconsistent, must be reconciled