IPSEC overlapping IP addresses

[corey.burden]

Looking for any suggestions here:

I have this scenario where I'm installing IPSec.  On my end, we have 3 subnets which require access to the remote site.  The 3 subnets are all /24.  But at the remote site, the engineers are only looking for a small set of IP's to prevent overlapping.  Does anyone have any suggestions on how to provision this?  I read up about doing a NAT but I would prefer no not to NAT if possible.  The 3 subnets 3.x,  20.x, and 25.x with about 255+ users across those 3 subnets to use the VPN.

Thanks,

Corey

[nspasov]

NAT is your friend here and the reason that it exists today :) Is there a reason why you don't want to use NAT?

Take a look at the following links:

http://packetpushers.net/how-to-build-an-ipsec-vpn-with-cisco-asas-overlapping-address-space/

https://supportforums.cisco.com/discussion/11408881/overlapping-subnets-ipsec-vpn-between-asa-and-ios-router

Thank you for rating helpful posts!

[corey.burden]

Thanks.  Really, we want to try to minimize any changes that we are doing plus we already have double natting going on and we are trying to get that down to a single nat.