[190549] in North American Network Operators' Group
Re: packet loss question
daemon@ATHENA.MIT.EDU (William Herrin)
Thu Jul 7 23:54:09 2016
X-Original-To: nanog@nanog.org
X-Really-To: <nanog@nanog.org>
In-Reply-To: <20160707195247.GO18345@sizone.org>
From: William Herrin <bill@herrin.us>
Date: Thu, 7 Jul 2016 23:53:38 -0400
To: Ken Chase <math@sizone.org>
Cc: "nanog@nanog.org" <nanog@nanog.org>
Errors-To: nanog-bounces@nanog.org
On Thu, Jul 7, 2016 at 3:52 PM, Ken Chase <math@sizone.org> wrote:
> ICMP is allowed to be dropped by intervening routers. Someone will quote an RFC
> at us shortly.
Hi Ken,
That's not correct. Routers might not generate an ICMP time-exceeded
packet for every packet whose TTL reaches zero, but that's not the
same thing. Routers dropping ICMP packets in transit would be bad.
Protocols like TCP depend on path MTU discovery and path MTU discovery
critically depends on ICMP.
Regards,
Bill Herrin
--
William Herrin ................ herrin@dirtside.com bill@herrin.us
Owner, Dirtside Systems ......... Web: <http://www.dirtside.com/>
