[c-nsp] mlppp vs multipath bgp on NM-4T

[Antonio Querubin]

I'm weighing the pros/cons of using MLPPP vs dual BGP links over 2 
synchronous serial lines attached to an NM-4T in a Cisco 3640.  The serial 
lines have different bandwidths - one serial line will be running at 8 
Mbps and the other will be 4 Mbps.  Both serial lines terminate on the 
same router at the remote end.  The routers will use BGP to pass routes 
(BGP on the multilink interface if using MLPPP).

The MLPPP method seems simpler as there would be only a single BGP peering 
link.  However, docs suggest MLPPP adds quite a bit of overhead.  How much 
extra overhead would MLPPP add to the 3640 cpu load?

Will multipath BGP work even though there is no MPLS-VPN or VRF 
configured on either router?

Will a single traffic flow be able to utilize the full aggregate 12 Mbps 
of bandwidth if using multipath BGP?

Which method would recover more quickly or tolerate the loss of one of the 
links?


Antonio Querubin
808-545-5282 x3003
e-mail/xmpp:  tony at lava.net