"Ben Butler" <ben.butler@c2internet.net> writes:
Anyone got any comments about how good or otherwise the Cisco 7200 + NPE-G1 or 7301, both with 1GB of RAM, is as a eBGP router + L2TP terminator for DSL subs, in terms of scalability for bandwidth through put & the number of VPDN sessions it can terminate before it dies. Are the two solutions effectively the same box or are there more technical differences beyond the obvious number of slots.
Well, the number of vpdn sessions that you can put on a VXR or a 7301 is going to have a lot more to do with your average customer's bandwidth use profile (ie, pps) than anything else. Right now, I'm looking at a 7206VXR/NPE300 in the US/Eastern time zone (so mid afternoon; all the gamer kids are home from school) that is serving as an LNS. 1811 callers, 52.5 Mbit/sec (10.5kpps) down, 33 Mbit/sec (9600 Kpps) up. 79% CPU. We offer an "unlimited" program, so there are some pretty heavy users in there - the hockey stick is pretty sharp. We did a side by side bakeoff several months ago of the 7301 vs. the 7206VXR/NPE300, and discovered that as a rule of thumb, the Kpps/1%cpu ratio was 3.8x as good as the VXR/NPE300. The used market for the 7301 is practically nonexistant, and new prices are about 3.2x the price of a used VXR loaded up with the interface complement we need. The interfaces on the VXR are fast ethernet not gige, but then again we weren't going to be able to saturate the faste anyway. Anyway, the sweet spot in the price/performance curve seems to be the 7206VXR with NPE-G1, if you can shop around and get the NPE for a good price. Junipers are as a rule more pricey, bigger physically, and more scaleable. Assuming you can share the traffic around via multiple tunnels, a farm of 7206VXRs with NPE300s offers box-level redundancy at a reasonable price. L2TPNS (http://sourceforge.net/projects/l2tpns) to which I was directed some time ago, shows promise but was lacking some critical features that we needed, and I was left coordinating an office move rather than writing software. Such is life. :( Anyway, it turned out that in our case, having a lot of box-level redundancy was more important than saving space, so we ended up staying with the VXR platform even with the NPE-300. The eval 7301 was in production use for several months and was completely trouble-free, so I agree with Woody's assessment that these are nice boxes. Regardless of what your users' usage is like, you're going to have an awfully tough time going over 20000 users on one box because of the IDB limit that Cisco imposes in their software for that platform. ---Rob