If you are staying with a PIX platform and are running an appreciable amount of traffic through the PIX, I would probably stay in the 7.2(x) train - upgrading to the latest release in that train. 7.2 codes seems to run a little faster in that platform and has better memory management. If you require a particular feature in 8.0, if your firewall is not currently running a large amount of traffic, 8.0 should also run reasonably well.
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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...