Hi guys,
Just thought I’d share a recent success story of implementing a low-cost MPLS network for my WISP backbone. I’ve had some frustrating issues getting things to a stable state and had to implement a few work-arounds for bugs, etc, but I decided to stick it out in the hope it would all come together at some point. And it now finally seems to be there.
My main celebration is the amount of performance I’m getting out of some relatively small and cheap pieces of hardware that will ultimately sit on a tower somewhere.
I decided to use RB912UAG-5HnD’s as my P and PE’s. Despite having only one ethernet interface I figured it would work well using VLAN’s to separate customer interfaces, backhaul, etc. The interface is gigabit and the device is only $79. I power these boards using a RB260GSP. I also use the 802.11 interface as an out-of-band remote management AP so I can do maintenance without climbing on the roof/tower.
Each RB is running the standard MPLS config of OSPF, LDP, and BGP back to a route reflector for both VPNV4 and L2VPN routes.
The big surprise is the performance results I just got from two laptops connected at either end of a VPNV4 tunnel running iperf. Here’s the results (wired only connections, no wireless)…
UDP test (multiple streams - single direction) = ~980mbps sustained throughput. CPU of RB was around 95-100%
TCP test (multiple streams - single direction) = ~750mbps sustained throughput. CPU of RB was around 80-90%
TCP test (single stream - single direction) = ~350mbps average throughput (was a bit choppy). CPU of RB ~ 40%
And remember, this is routed in to the MPLS (VPNV4), not bridged.
Whilst all this was going on, I had a ping running between the two laptops. No lost packets, and RTT varied between 1ms and around 15ms, mostly 2-5ms.
Very impressive for a network of $79 routers 
Rich