The E3 and E4 designation represents the version of the analysis engine installed on the sensor. The signature developers create signatures to the most current release of the analysis engine (E4 currently). Without the most current analysis engine (and an active license) you cannot apply signature updates to the sensor.
It is possible to upgrade an AIP-SSM from release 6.0 to 7.0 using the current 7.0 upgrade package (.pkg file).
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...