Waste will kill ipv6 too

William Herrin bill at herrin.us
Fri Dec 29 17:43:02 UTC 2017


On Fri, Dec 29, 2017 at 5:27 AM, <sthaug at nethelp.no> wrote:

> It's rather interesting how parsing of variable length addresses was
> thought to be way too complicated - while parsing of IPv6 extension
> header chains of unknown length was okay.
>

IIRC, IPv6 extension headers are optional. The router does have to check if
there are any hop-by-hop options but it doesn't need to examine more than
the first extension header (and always the same byte offset) to determine
if it has to look. More, it's allowed to reject the packet with a parameter
problem rather than process the header.

The originating and destination nodes have to pay attention to all
extension headers, but then they always did have to process packets with
information of variable lengths.

Regards,
Bill Herrin


-- 
William Herrin ................ herrin at dirtside.com  bill at herrin.us
Dirtside Systems ......... Web: <http://www.dirtside.com/>



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