Looking at your nat config and if im reading your interfaces correctly it appears that you have a global 101 for interface (outside) and a global 1 for interface (ISP) if you initiate traffic from the inside interface from the 172.23.48.0 255.255.252.0 network it should be NAT'd to the outside IP of the (ISP) interface, is this working?
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...