[c-nsp] bonded T1s into 7206VXR

[Jason Ackley]

On Mon, 21 Feb 2005, Adam Greene wrote:

> My question is: will this bonded T1 service act like a single circuit? I.e.
> if I have a single TCP connection that needs, say 4M bandwidth, will the
> bandwidth be equally distributed across all three 1.5M circuits? I am also
> wondering if the bonding will work any differently if the (3) T1's are
> across (2) PA-MC-2T1 cards vs a single PA-MC-4T1 card.

 Greetings,
 
 I have some connections from AT&T in this manner and expect that you will 
 have the same thing that I have.

 If you are running BGP with multiple paths over the circuits, yes, it
 will allow a single connection to use all of the bandwidth. The equal 
 paths do a good job of load balancing between the circuits.

 This is done in the standard way of a BGP session between the loopback 
 adapters (easy to get running).

 As far as balancing, here are the stats from one of our 4xT1 bundles:
 (from a 'show int sum')

  Interface              IHQ   IQD  OHQ   OQD  RXBS RXPS  TXBS TXPS TRTL
------------------------------------------------------------------------
* Serial0/0/0:0            0     0    0  3957 431000   87 142000   65    0
* Serial0/0/1:0            0     0    0  2830 438000   87 326000  112    0
* Serial0/0/2:0            0     0    0  8893 434000   87 203000   75    0
* Serial0/0/3:0            0     0    0 14730 440000   87 363000  108    0

 (goes into a PA-MC-4T1 on a 7507)

 AT&T uses PPP encaps, and it just worked when we turned up the circuits. 
 The ILEC was a day late on the 3rd one, but they added to the bundle 
 without any problems.

 As far as splitting between PAs, it doesnt matter if you are doing it at 
 the BGP/route layer. If you can, it would be a good idea to split them 
 for protection from card failures etc.

 Good luck!


cheers,
--
jason