RP will build the source-tree towards the source. First-hop router will start sending multicast instead of unicast once it has the tree.
-- Marko Milivojevic - CCIE #18427 Senior Technical Instructor - IPexpert YES! We include 400 hours of REAL rack time with our Blended Learning Solution! Mailto: [email protected] Telephone: +1.810.326.1444 Fax: +1.810.454.0130 Web: http://www.ipexpert.com/ On Tue, Jul 6, 2010 at 15:32, Bojan Zivancevic <[email protected]> wrote: > Can someone clarify this to me? It is a theory question, so maybe too > in-depth but... :) > > > > It is about PIM-SM Register process. When a router directly connected to a > multicast source wants to be able to forward traffic, it sends a register > message to the RP. This an unicast message, and within it there’s a > multicast packet encapsulated. > > > > Now, if there is no parties interested for this traffic, RP will send back > Register-Stop message. Then sending router will start Register Suppression > Timer and after it times out, it will send again PIM register. And so on. > > > > If there are interested parties, then RP will unpack the encapsulated > multicast packet and forward it immediately. Then it should notify the > sending router to stop sending unicast packets (which are for registration > purposes, basically), because it can send normal multicast ones instead. > > > > My question is – how does RP notify the sending router to stop sending > unicast PIM Register messages? Is it also PIM Register-stop? But how will > the sending router differentiate these two PIM Register messages? How will > it know when to start Register Suppression Timer (and keep on sending > unicasts), and when to start sending normal multicast packets? > > > > Thanks in advance. :) > > > > Best Regards, > > > > Bojan Zivancevic > > Network Engineer > > _______________________________________________ > For more information regarding industry leading CCIE Lab training, please > visit www.ipexpert.com > > _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com
