Raw sockets

[Steven Majewski]

On Thu, 20 Dec 2001, Fredrik Juhlin wrote:

> On Thu, Dec 13, 2001 at 07:52:11PM -0800, Andrae Muys wrote:
> > Might I suggest you first check out Stevens 'TCP/IP Illustrated Vol 1'
> > as it will explain in excelent detail how traceroute is built using
> > UDP not ICMP :).
> He might have meant tracert (or whatever it's called on Win32
> systems, maybe they even call it traceroute in the newer versions) which
> IIRC uses ICMP echo requests rather than random high UDP ports.

The message Fredrik Juhlin was replying to never got to me, but I'm
guessing from what I see above that it was in reply to my post.
  What *I* meant was that, whatever type of packet you send out, you're
relying on the ICMP error returned when the TTL gets decremented to zero.
Use of UDP is optional. ICMP is required.


-- Steve