VPN ISDN Backup

[karl.jones]

Hi

I want to have a 3600 router terminating VPN connections at the CO from 1700 routers at the spoke sites. I will be using IPSEC/3DES and GRE to allow for routing. But I want to put and ISDN card in the 1700 routers, and provide backup to the CO. I have a ras box at the CO which looks after all of our RAS connections and preferrably would like to dial in to this to provide reiliance. This box just provides standard IP routing with no VPN/IPSec functionality. All of the sample configs I seen show the 1700 router dialing into a VPN box, maybe the same one that provided the VPN across the internet or perhaps one next to it. Is there any security reasons why I shouldnt dial straight into our LAN at the CO to provide internet VPN backup or is this a valid solution.

Regards

[fmeetz]

As you rightly said it is a secuirty reasons only, otherwise you can very well dial directly into the RAS.Since it does not have IPSec it will not be secure. Also you will have o do some additional config on the 1700 with respect to Access list in case you want to specify who can who cannot "Access- List", since the command usage in IPSec is different from ordinary usage.