DMVPN headend connection speed

[J_Vansen_S]

Good Day,

We are in the process of determining and going to subscribe the speed/bandwidth required from Telco for our DMVPN HUB Headend.

Apparently we are going to have max of 30 remote sites(spokes)

Our design is basically just 1 single headend(hub) and spokes.

1x ISR 3925 (HUB)

30x ISR 2911 (SPOKES)

Spokes subscribed speed is either 512kbps or 1Mbps depending on sites.

How we can determine the optimal speed/bandwidth to subscribe on our HUB.

Any advise greatly appreciated.

[Jason Gervia]

Assuming worst case scenario (30 sites x 1 MEG connectivity) == 30 megs connectivity if all sites are connected and passing traffic at the same time, correct? 

The 3925 can more than handle 30Mb/sec encrypted - so to play it safe you could go with 30, and assume that you should rarely, if ever hit that mark.

The real question is whether you know how much a site typically uses of their bandwidth - so you could get a more accurate number and be able lower the bandwidth requirement at the hub and save $$$ if that is an issue.

--Jason