<div dir="ltr"><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_extra"><br><div class="gmail_quote">On Tue, Apr 3, 2018 at 10:48 AM, Jesper Louis Andersen <span dir="ltr"><<a href="mailto:jesper.louis.andersen@gmail.com" target="_blank">jesper.louis.andersen@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><span class="">On Tue, Apr 3, 2018 at 4:27 PM Michael Welzl <<a href="mailto:michawe@ifi.uio.no" target="_blank">michawe@ifi.uio.no</a>> wrote:<br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">please, please, people, take a look at the ietf taps (“transport services”) working group :-)<br>
<br></blockquote><br></div></span><div class="gmail_quote">I tried looking it up. It seems the TAPS WG is about building a consistent interface to different protocols in order to get a new interface rather than, say, the bsd socket interface.<br><br></div><div class="gmail_quote">But my search turned up several drafts from the WG. Did you have one in particular in mind?<br><br></div><div class="gmail_quote">I think the major reason to implement new protocols inside UDP is mainly due to a lot of existing devices out there, namely firewalls, NAT systems, and so on. The internet is extending itself by successive patching of older standards, rather than a replacement of older standards. I do note that this is how biological systems tend to work as well, but I have no good reason as to why that is what happens with internet standards where we in principle could redesign things. But perhaps already deployed stuff makes the systems susceptible to iterative patching.<br></div></div></blockquote><div><br></div><div class="gmail_default" style="font-size:small">Middle boxes are a huge problem.</div><div class="gmail_default" style="font-size:small"></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div class="gmail_quote"><br></div><div class="gmail_quote">The bufferbloat angle is also pretty clear: CoDel is a brilliant solution but it requires you to change queues in the network. So it seems people are trying to patch TCP instead, through something like BBR; again mimicking a biological system.<div class="gmail_default" style="font-size:small;display:inline"></div><br></div></div></blockquote><div><br></div><div class="gmail_default" style="font-size:small">To some extent: but BBR is in fact a breakthrough independent of bufferbloat (and in fact will induce > 1RTT of buffer, which is far from ideal).</div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small">For example, BBR works tremendously better than loss based congestion avoidance algorithms in the face of high RTT/lossy networks, like those</div><div class="gmail_default" style="font-size:small">faced in satellites or the developing world.</div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div class="gmail_quote"></div></div>
</blockquote></div><br></div><div class="gmail_extra"><div class="gmail_default" style="font-size:small">To get to really good RTT's (with low jitter), you still need fq_codel (or similar). You just can't get there by hacking TCP no matter how hard you try...</div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small">See both on their independent merits: it is part of the Elephant; it's easy to think your "solution" solves</div><div class="gmail_default" style="font-size:small">the whole problem, when it doesn't. I will cheer both fq_codel and similar flow queuing AQM's that may appear</div><div class="gmail_default" style="font-size:small">*and* BBR loudly.</div><div class="gmail_default" style="font-size:small"> - Jim</div><div class="gmail_default" style="font-size:small"><br></div><br></div></div>