One thing to note is what ACS considers a session, and what the NAS does. ACS defines a session as the unique combination of username,NAS IP, and source TCP Port number. So ACS will allow the same user to authenticate multiple times to the same device since all values of that triplet remains the same. Just FYI
Table of ContentsIntroductionVersion HistoryPossible Future
UpdatesDocuments PurposeNAT Operation in ASA 8.3+ SectionsRule Types
Network Object NATTwice NAT / Manual NATRule Types used per SectionNAT
Types used with Twice NAT / Manual NAT and Network Obje...
Table of Contents Introduction:This document describes details on how
NAT-T works. Background: ESP encrypts all critical information,
encapsulating the entire inner TCP/UDP datagram within an ESP header.
ESP is an IP protocol in the same sense that TCP an...