You can put two PIX at one site and have your DMZ in the middle of the two, some peole do this although it's not entirely necessary (although definately more secure if set up right).
To get your VPN working though, all you really need is one 506 at each site with the VPN configuration on them, the inside interface connects to your inside network/router, and your outside interface connects to your outside router/DSL/cable modem.
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...