> and a costly relay would have to be used to perform triangle routing. My understanding of triangle routing has mobile device A sending to B directly but with a care/of return address of a mobile proxy that knows where A is now. C forwards the message. A is moving and it's IP changes as it crosses cells. Thus B sends care/of C which forwards to A. This forms a triangle.
I also thought that symmetric nat traversal requires an outbound proxy and that neither A or B communicate directly but both send packets to the outbound proxy which forwards all communication. This forms a V. Am I correct or wrong? Christopher Priest [EMAIL PROTECTED] --- On Fri, 11/28/08, yannick <[EMAIL PROTECTED]> wrote: > From: yannick <[EMAIL PROTECTED]> > Subject: Re: [Ekiga-list] symmetric nat traversal > To: "Ekiga mailing list" <[email protected]> > Date: Friday, November 28, 2008, 1:40 PM > Le vendredi 28 novembre 2008 à 19:15 +0100, Martin Uecker a > écrit : > > On Fri, Nov 28, 2008 at 04:17:35PM +0100, Piotr > Morgwai Kotarbiński wrote: > > > The document is 5 years old and last modification > of the project page > > > occurred also in 2003, so I'm not sure if > anybody is working on it > > > still... I'll try to contact the author or > other members of the > > > project and ask what's the status. > > > > > > Thanks > > > > > > Morg > > > > > > > It seems that Miredo [http://www.remlab.net/miredo/] > has symmetric > > NAT traversal support. It might be possible to acquire > an IPv6 > > address using teredo (Miredo) on both clients and then > communicate > > with ipv6. In general, this would be a much more > elegant solution > > then to implement NAT traversal in each and every > program. Since > > Teredo is also supported on Windows, this might also > work for > > Windows users. > > > > "Teredo is not compatible with all NAT devices. Using > the terminology of > RFC 3489, full cone, restricted and port-restricted NAT > devices are > supported, while symmetric NATs are not. National Chiao > Tung University > proposed SymTeredo which enhanced the original Teredo > protocol to > support symmetric NATs, and the Microsoft and Miredo > implementations > implement certain unspecified non-standard extensions to > improve support > for symmetric NATs. However, connectivity between a Teredo > client behind > a symmetric NAT, and a Teredo client behind a > port-restricted or > symmetric NAT remains seemingly impossible. > > Indeed, Teredo assumes that when two clients exchange > encapsulated IPv6 > packets, the mapped/external UDP port numbers used will be > the same as > those that were used to contact the Teredo server (and > building the > Teredo IPv6 address). Without this assumption, it would not > be possible > to establish a direct communication between the two > clients, and a > costly relay would have to be used to perform triangle > routing. A Teredo > implementation tries to detect the type of NAT at startup, > and will > refuse to operate if the NAT appears to be symmetric. (This > limitation > can sometimes be worked around by manually configuring a > port forwarding > rule on the NAT box, which requires administrative access > to the > device)." > > http://en.wikipedia.org/wiki/Teredo_tunneling#Limitations > > Well, according to wikipedia, it seems toredo has the same > limitations > as Ekiga currently has... > > > > > Martin > > > > > > _______________________________________________ > > ekiga-list mailing list > > [email protected] > > http://mail.gnome.org/mailman/listinfo/ekiga-list > -- > Me joindre en téléphonie IP / vidéoconférence ? > sip:[EMAIL PROTECTED] > Logiciel de VoIP Ekiga : http://www.ekiga.org > http://wiki.ekiga.org/index.php/Which_programs_work_with_Ekiga_%3F > > _______________________________________________ > ekiga-list mailing list > [email protected] > http://mail.gnome.org/mailman/listinfo/ekiga-list _______________________________________________ ekiga-list mailing list [email protected] http://mail.gnome.org/mailman/listinfo/ekiga-list
