Thanks a lot, guys. I definitely learned a lot from all of you :-) -Simon
On Wed, Jul 16, 2008 at 10:16 AM, <[EMAIL PROTECTED]> wrote: >> I have to jump in, since I am also interested :-) >> >> My question is, what do you think the cost/benefit of L2VPN over VPLS? >> It seems that L2VPN is restricted to point-to-point and there is a >> separate vrf (and a routing table) for each link, while VPLS maintains >> a single vrf and routing table. Have you guys thought about using >> VPLS? Or is there any problems with it? Maybe scalability? > > Can't really comment the (Juniper proprietary) L2VPN. However, we use > both Martini tunnels (L2circuit in Juniper terminology) and VPLS. The > two technologies are quite different: > > - L2circuit (and L2VPN) give you a point-to-point link. You can think > about the technology as a pipe where packets are inserted at one end > and come out at the other end. No MAC address learning is necessary. > Troubleshooting is fairly simple (no need to go looking for specific MAC > addresses and where they originate). Scaling is fairly good - we have > M7i routers with more than 2000 L2circuits. You need to watch your FEB > memory utilization, though. > > - VPLS give you a layer 2 multipoint network - in effect you are making > your network look like a large LAN. MAC address learning is necessary, > and only the MX boxes are able to do this in hardware. Replication of > broadcast/multicast/unknown unicast traffic is at the *source*, which > has the potential to melt down your network (e.g. one 100 Mbps stream > replicated to 20 different PE routers gives you 2 Gbps of traffic from > your ingress router towards your network core). Both the technology > and the troubleshooting is significantly more complex than L2circuit/ > L2VPN. > > I don't want to give the impression that VPLS is all gloom and doom. > Juniper has done a reasonable job of making the technology stable, > especially in later JunOS versions, and P2MP LSPs help significantly > with the ingress replication problem. However, L2 point-to-point is > still a significantly simpler technology no matter how you look at it. > > Steinar Haug, Nethelp consulting, [EMAIL PROTECTED] > _______________________________________________ juniper-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/juniper-nsp
