Options
Why is UDP needed?
gojericho0
Member Posts: 1,059 ■■■□□□□□□□
in Off-Topic
I got to thinking of this when I was doing some packet captures. Why is UDP header used with a unique port number instead of just assigning each application a unique ID in the IP header?
Wouldn't this still allow application multiplexing and allow less packet overhead?
Wouldn't this still allow application multiplexing and allow less packet overhead?
Comments
-
Options
UnixGuy
Mod Posts: 4,566 Mod
I thought each UDP (or TCP) packet has the port number of the application it's destined to ? -
Options
tiersten
Member Posts: 4,505
The IP protocol field is only 8 bits. Most of them have been preassigned in RFC790.
You'll end up with nasty hacks and special cases because you're overloading the field and not using it for its intended purpose. The layers are split for a reason. IP is for routing. -
Optionstiersten
Member Posts: 4,505
It does. gojericho0 wants to know why you don't just use the protocol field in the IP header as a port number.I thought each UDP (or TCP) packet has the port number of the application it's destined to ? -
Optionsgojericho0
Member Posts: 1,059 ■■■□□□□□□□
The IP protocol field is only 8 bits. Most of them have been preassigned in RFC790.
You'll end up with nasty hacks and special cases because you're overloading the field and not using it for its intended purpose. The layers are split for a reason. IP is for routing.
Thanks! this cleared things up greatly.