I remember reading that all Cisco devices that support VPN solutions, comply with the IETF standards. That simply translates to the fact that establishing a tunnel with a third party device is theoritically possible as long as that device too complies with the standards. Third party clients should work with the PIX if they are RFC compliant.
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...