thanks. good answer. low risk answer. "it will work" answer. If its a variant of "the last mile is your problem" problem, I'm ok with that. If its a consequence of the middleware deployment I feel like its more tangibly bad decision logic, but its real.
-G On Fri, Jan 19, 2018 at 9:50 AM, Mark Andrews <ma...@isc.org> wrote: > Because the CDN delivers to your customers not you. It’s your customers link > requirements that are the ones you need to worry about. If you support > jumbo frames to all of your customers and their gear also supports jumbo > frame then sure go ahead and use jumbo frames otherwise use the lowest > common denominator MTU when transmitting. This is less than 1500 on > today Internet and encapsulated traffic is reasonable common. > > embedded CND <--> NAT64 <--> CLAT <--> client > 1500 14XX 1500 > embedded CDN <--> B4 <— > 6RD <— > client > 1500. 14XX 1500 > > Now you can increase the first 1500 easily. The rest of the path not so > easily. > >> On 19 Jan 2018, at 9:53 am, George Michaelson <g...@algebras.org> wrote: >> >> 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 <do...@telecurve.com> wrote: >>> Vincent, >>> >>> Thanks. That URL explained a lot. >>> >>> On Tue, Jan 9, 2018 at 3:11 AM, Vincent Bernat <ber...@luffy.cx> wrote: >>> >>>> ❦ 8 janvier 2018 15:08 -0800, joel jaeggli <joe...@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) >>>> > > -- > Mark Andrews, ISC > 1 Seymour St., Dundas Valley, NSW 2117, Australia > PHONE: +61 2 9871 4742 INTERNET: ma...@isc.org >
