Hi, Narayanan and Das: I agree with you guys. I also think relay peer routing mode also be helpful in wireless situation, by considering in China most mobile devices gets NATed because of depletion of global IPv4 address.
In http://tools.ietf.org/id/draft-jiang-p2psip-relay-00.txt, we prposes an extension to make the direct response and relay peer available in RELOAD. So I think these two additional routing modes will be helpful in certain situations. The draft provides avaiable tools to support them and it depends on the peer to decide which will be used. For example, it can based on past experience on different routing modes, such as, symmetric recursive, diret response or relay peer, to decide which one will be used first. The peer also use ping or some other messages to perodically to try different routing modes to get the success rate of the respective routing mode and make the determination. Regards Jiang XingFeng > > Direct routing has huge benefits in the presence of wireless > devices. The current routing choices assume that we need > symmetric routing to handle NATs and hence, that is the common > case. It turns out that there are several cellular networks today > that are non-NATed (shocking, but, true for now, at least in the > US). So, it would be bad to not take advantage of that for > improving the lookup latency. Worse still, by forcing symmetric > routing all the time, we would have cut the budget for the maximum > number of wireless hops in one direction to half (with only 3-4 > wireless hops budgeted for the entire lookup to have an acceptable > call setup latency, this makes it significantly worse). > > So, we really should make direct routing part of the base spec if > we want RELOAD working well with wireless devices. > > Vidya > > > -----Original Message----- > > From: [EMAIL PROTECTED] > > [mailto:[EMAIL PROTECTED] On Behalf Of Das, Saumitra > > Sent: Friday, November 14, 2008 1:03 PM > > To: [email protected] > > Subject: [P2PSIP] The case for direct response support in RELOAD > > > > Hi all, > > > > I think we should consider a direct reponse based > > asymmetric routing as part of the base draft in RELOAD. There > > are several advantages 1. The latency of a transaction is reduced. > > 2. Given the increasing spread of mobile devices that may > > participate in such overlays direct response routing can > > reduce the resource usage on multiple wireless hops. > > 3. Many hosts (such as in mobile broadband networks) are not > > always behind NATs and in such cases direct response routing > > is even more beneficial as we do not need to perform ICE. > > > > Another draft (ref 1) also supports this view. > > > > openDHT also seems to support such as mode of operation (see > > Ref 2). While it mainly operates on a testbed with public > > Ips, one can make the case that there may be many such nodes > > in a deployed RELOAD overlay. E.g. university machines, > > wireless hosts etc. > > > > Ref 1: http://tools.ietf.org/id/draft-jiang-p2psip-relay-00.txt > > Ref 2: Sean Rhea, Byung-Gon Chun, John Kubiatowicz, and Scott > > Shenker. Fixing the Embarrassing Slowness of OpenDHT on > > PlanetLab. Proceedings of USENIX WORLDS 2005, December 2005. > > > > Thanks > > Saumitra > > _______________________________________________ > > P2PSIP mailing list > > [email protected] > > https://www.ietf.org/mailman/listinfo/p2psip > > > _______________________________________________ > P2PSIP mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/p2psip > _______________________________________________ P2PSIP mailing list [email protected] https://www.ietf.org/mailman/listinfo/p2psip
