It all depends on what you are trying to accomplish and what features you are using in each ASA. The outside ASA, as a firewall can host serveral inside networks (limited by the number of interfaces in the ASA) each netowrk can have a different firewall policy assigned. If that meets your firewall needs, then you might not require a second set of ASAs.
You have not provided enough network requirements detail to even make an guess of what you need.
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...