Not really!! with a 1:many - you will be using Port Address Tranlsation. You could have 1000 internal IP addresses and NAT them to 1 external IP address - and the ASA will have a PAT translation table with specific translation ports.
You could only have 1 internal IP and you could make 10,000 seperate outbound connections to the internet and the same priciple applies.
For every seperate outbound connection, the ASA creates 1 x PAT table entry. So that would be 65535-1 = 65534 left.
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...