Re: New Version Notification for draft-bonica-6man-frag-deprecate-00.txt

[Ole Troan <[e-mail]>]

Randy,

>>>> If it's a statement of fact, it shouldn't use RFC 2119 language. It
>>>> should simply state the truth: "Network operators might filter IPv6
>>>> fragments."
>>> s/might/do/
>> would you be able to answer why and where?
> 
> perceived, rightly or wrongly, as an attack vector.  they do similarly
> for v4.  often at enterprise borders (hell, they filter 53/tcp), and
> occasionally inter-isp.

I'm aware of the Enterprise borders, I was a bit more surprised at the inter ISP filtering.
with my user hat on, I'm not paying my ISP to drop my packets. ;-)
I understand why an ISP would filter ISPs towards its own infrastructure,
but what would be the reasoning for filtering fragments that it transits?

> in reality, you can not count on pmtud working, and don't bet your buns
> on frags getting through.

right, so something has to change. if that's in-band MTU discovery for all L4 protocols, or if it is something else I don't know.

cheers,
Ole