What's the usage for Host header in http?

Question

In the http protocol, I saw sometimes we have a HOST header, like

Host: www.google.com:3333

what's the usage for this header? Why do we need this header?

score 7 · Accepted Answer · answered Feb 13 '13 at 01:04

7

When an http request hits a server, it only hits an IP/Port combination. This header shows which host was actually requested.

Many machines serve multiple hosts from the same IP. Without this header, they wouldn't know which host was requested.

answered Feb 13 '13 at 01:04

Kylar

score 0 · Answer 2 · edited May 23 '17 at 10:32

0

Answer from here.

See section 14.23 of the HTTP spec which specifies that the port should be included if its not the default port of 80.

edited May 23 '17 at 10:32

Community

answered Feb 13 '13 at 01:06

Ye Lin Aung

2 Answers2