I have 2 users that need VPN into the office from the same originating IP. They are not able to connect simultaneously though. Is this a limitation of the Cisco box, or of the Linksys router on site there?
EDIT: Source machines are both using Cisco VPN Client, V5
Best Answer
If the source machines are connecting via a NAT router then standard IPsec VPN's wont work - the ESP protocol used by IPsec doesn't play friendly with NAT's as they use port remapping and ESP doesn't have a concept of ports. An L2TP\IPsec VPN can tunnel multiple concurrent clients through a NAT because it encapsulates the IPSec payload inside a UDP tunnel which does play nicely with NAT environments.