All the 30xx models run the same software. The BUN (bundle) simply means the 30xx comes with a US power supply and software included, whereas with the non-BUN model numbers you have to order a power supply separately.
The RED models double the number of SEPs and add another power supply, so a 3030-RED is physically the same as a 3060-NR, except the 3060 has more memory and the 3030-RED will have two power supplies.
A 3060-RED and a 3080-NR are the same device from a hardware perspective.
Not sure if it's the bottom ones that are redundant, but yes, if you have 4 SEP's then 2 are active and two are backup. In the event of a failure no sessions are lost, the encryption functions merely switch over to the new SEP. You can check Monitoring - Sessions - SEPs to see what percentage of sessions are on what SEP card.
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...