As per my understanding in case on ACL or Nat comes in ASA is , if the traffic initiate from inside network & want's to communicate to outside server(Internet) which 1st thing need is to be permit by ACL . If ACL Permit's the traffic then only it will forward the traffic otherwise will drop . After completing its looking for Global IP which he will get from the NAT , then it will route the packet .
In Case of Connection from outside to inside ,give you an example .
If your web server which is located inside segment & source is a Host which reside behind the Outside segment(Internet) wants to access the server , then in this case the Host(Internet) attempt to connect to webserver(Inside) on public ip which he get it through Static NAT . Then ASA Check the ACL if permit then forward the Packet & After coming to Nat interface it will unwrap the packet & transfer the packet to its original Local Ip address .
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...