Hi all, I have a brief suggestion for a match/target which I am unable to to write myself of many reasons, mainly that I am a very very lousy coder =). If someone is already working on this, disregard from this mail.
What I would like to propose is an ECN match/target. During the last days, I've read through a couple of RFC's and that's where this request stems from. If anyone else finds this interesting and has a little bit better coding habit than I... Basically, I have read or at least scanned through RFC 1323, 2018, 2883, 2884 and 3168 and I believe this is possible after thinking it through, but I hope anyone else can comment on feasibility. First off, I have yet to finish up on reading RFC 3168 so I am not quite sure if what I would like to propose will break current standards but ... =) I would first of all like to see a match that makes it possible to match packets based on their ECN values as described in RFC 3168, or possibly on any value that the ECN field may take. I would also like to see a target that lets us set the ECN values. As with the FTOS and TOS targets, I would generally believe the TOS type of match would be better (ie, it would block the user from setting ridiculous values that are more or less not valid according to RFC 3168.). AFAIK, this would include the following settings: 00 Not-ECT 01 ECN Capable Transport(1) 10 ECN Capable Transport(0) 11 Congestion Experiences (CE) These extensions would make it possible for us to: 1) Reset all ECN enabled packets leaving a specific network or going to a specific network. 2) We can use this match to match packets leaving the firewall and possibly do specific routing to get around misbehaving routers/firewalls blocking ECN enabled packets. 3) Possibly mark packets based on their CE values and make it slant over to other routes. Ie, we receive CE packets and we can then set a special mark on packets and hence give another route higher priority. Another solution would be to use some sort of userspace queue which would rewrite the routing entries to give another route higher priority. A huge set of other possibilities? Of course, we would also be able to ECN enable our local networks without worrying about other networks such as the Internet. According to RFC 2884 this should give approximately 20-60% better throughput under moderate through heavy congestion, if I am not totally off=). Packets destined for the Internet could then be reset to Non-ECT. On larger networks this could possibly be of some interest... Any comments on this, am I totally off or is this actually possible without breaking all protocols available? Anyone willing to undertake a project like this? Have a nice day, Oskar Andreasson http://www.boingworld.com http://people.unix-fu.org/andreasson/ mailto: [EMAIL PROTECTED]
