if I was an ISP (Im not) and a CDN came and said "we want to be inside you" (ewww) why wouldn't I say "sure: lets jumbo" not even "asking for a friend" I genuinely don't understand why a CDN who colocates and is not using public exchange, but is inside your transit boundary (which I am told is actually a bit thing now) would not drive to the packet size which works in your switching gear. I understand that CDN/DC praxis now drives to cheap dumb switches, but even dumb switches like bigger packets dont they? less forwarding decision cost, for more throughput? On Fri, Jan 19, 2018 at 6:21 AM, Dovid Bender <dovid@telecurve.com> wrote:
Vincent,
Thanks. That URL explained a lot.
On Tue, Jan 9, 2018 at 3:11 AM, Vincent Bernat <bernat@luffy.cx> wrote:
❦ 8 janvier 2018 15:08 -0800, joel jaeggli <joelja@bogus.com> :
N00b here trying to understand why certain CDN's such as Cloudfare have issues where my MTU is low. For instance if I am using pptp and the MTU is at 1300 it wont work. If I increase to 1478 it may or may not work. PMTUD has a lot of trouble working reliability when the destination of the PTB is a stateless load-balancer.
More explanations are available here: https://blog.cloudflare.com/path-mtu-discovery-in-practice/ -- Don't comment bad code - rewrite it. - The Elements of Programming Style (Kernighan & Plauger)