Planning for a WAN deployment

[Paolo Rocca]

Hi,

i work for a small company in regional Australia.

I've been recently tasked to provide a design to upgrade the lan/wan infrastructure of a local gov entity.

For the lan part, is pretty straight forward, i'll go for a bunch of small business 500 series, L3.

The idea is to get rid of spanning tree and go full routed.

For the routers though i'm having a hard time picking the right model..

The network consist of a central office, a relatively large branch and two small remote offices. all you get around here is DSL.

The main office will have 3 ADSL connections, around 20mbps each. 2 will be used for vpn and the last one for internet access.

the second site will have 2 connections, again 1 for vpn to the main office and 1 for internet.

the 2 small branches just 1 connection each.

Which model of router would you use to support this topology?

My actual idea is a 3925 for the main office, a 1900 series for the second and 800 series for the branches.

it would be nice however if i could downsize the 3900 series a bit as it gets pretty pricey.

would it be better to use maybe 3 separate 800 series instead?

Thanks in advance

[Elliott Willink]

This is a very difficult question to answer without knowing what sort of services you are intending to run.

A 3900 series feels overkill for 3 ADSL connections running crypto to remote routers (also on ADSL) as best case you will end up with a 1mbit circuit due to your upload speed at each end... but then again, actually running 3 ADSL connections concurrently is very unusual in the first place.

What town are you in? If this was me, I would be investigating if anyone (Telstra or AAPT/TPG?) offers EFM/EoC/SHDSL. I would put this in at head office with a 1921-SEC running an EFM-capable HWIC + ADSL2 HWIC. EFM/EoC/SHDSL would connect to the branch sites via a VPN and the ADSL would be for web browsing and a backup VPN if the primary link goes down.

Branch sites I would run 867VAE-SEC's if the budget was tight, then run BGP to control routing to the EFM/DSL at head office (I don't think you get much else on the 867's)...

But maybe you are doing something much more complex.. Without a more detailed description I can't really make to much of a suggestion other than the above.

Regards,

Elliott