Re: What do you consider acceptable packet / session modification for a network operator?

On Fri, 26 Dec 2025 at 18:08, Marco Moock via NANOG <nanog@lists.nanog.org> wrote:

If that fixes the problem, PMTU discovery (mandatory for IPv6 and IPv4 with DF bit) is broken and that means UDP, IPsec, GRE etc. all fail.

The ISPs I used emit ICMP packet too big messages.

While it would be terrific if this would work, reality is that content networks all have tried, and all have resorted to fixing lower MSS. Internet is just too broken. Idealistically I agree. -- ++ytti