[107263] in North American Network Operators' Group

home help back first fref pref prev next nref lref last post

Re: IP Fragmentation

daemon@ATHENA.MIT.EDU (Glen Kent)
Thu Aug 28 20:14:38 2008

Date: Fri, 29 Aug 2008 05:44:28 +0530
From: "Glen Kent" <glen.kent@gmail.com>
To: tony.li@tony.li
In-Reply-To: <8F1036ACA3624834A438CD51E58963BD@ad.redback.com>
Cc: OPS Gurus <nanog@merit.edu>
Errors-To: nanog-bounces@nanog.org

I understand, but the question is what if they dont?

Or let me rephrase the question.

What do standard implementations do if they send a regular IP packet
(no DF bit set) and receive an ICMP dest unreachable - Fragmentation
reqd message back? Do they fragment this packet and then send it out
again with the MTU reported in the ICMP error message, or is the ICMP
error message silently ignored?

Glen

On 8/29/08, Tony Li <tony.li@tony.li> wrote:
>
>
> |OK, so what happens if a transit router does not support IP
> |fragmentation
>
>
> All IPv4 routers are supposed to support fragmentation per RFC 1812 (Router
> Requirements), section 4.2.2.7.
>
> Tony
>
>


home help back first fref pref prev next nref lref last post