From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Paasch Subject: Re: [RFC 0/2] Delayed binding of UDP sockets for Quic per-connection sockets Date: Thu, 01 Nov 2018 15:11:18 -0700 Message-ID: <20181101221118.GG1685@MacBook-Pro-19.local> References: <20181031232635.33750-1-cpaasch@apple.com> Mime-Version: 1.0 Content-Type: text/plain; CHARSET=US-ASCII Content-Transfer-Encoding: 7BIT Cc: Network Development , ianswett@google.com, lhedstrom@apple.com, jri.ietf@gmail.com, Eric Dumazet To: Willem de Bruijn Return-path: Received: from ma1-aaemail-dr-lapp02.apple.com ([17.171.2.68]:34458 "EHLO ma1-aaemail-dr-lapp02.apple.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727115AbeKBHQP (ORCPT ); Fri, 2 Nov 2018 03:16:15 -0400 Content-disposition: inline In-reply-to: Sender: netdev-owner@vger.kernel.org List-ID: On 01/11/18 - 17:51:39, Willem de Bruijn wrote: > On Wed, Oct 31, 2018 at 7:30 PM Christoph Paasch wrote: > > > > Implementations of Quic might want to create a separate socket for each > > Quic-connection by creating a connected UDP-socket. > > > > To achieve that on the server-side, a "master-socket" needs to wait for > > incoming new connections and then creates a new socket that will be a > > connected UDP-socket. To create that latter one, the server needs to > > first bind() and then connect(). However, after the bind() the server > > might already receive traffic on that new socket that is unrelated to the > > Quic-connection at hand. > > This can also be achieved with SO_REUSEPORT_BPF and a filter > that only selects the listener socket(s) in the group. The connect > call should call udp_lib_rehash and take the connected socket out > of the reuseport listener group. Though admittedly that is more > elaborate than setting a boolean socket option. Yeah, that indeed would be quite a bit more elaborate ;-) A simple socket-option is much easier. Cheers, Christoph > > > The ideas for the implementation came up after a discussion with Ian > > and Jana re: their implementation of a QUIC server. > > That might have preceded SO_TXTIME? AFAIK traffic shaping was the > only real reason to prefer connected sockets.