I am looking for documentation or a config on how to implement IPSEC encrypted ISDN dialup internet access, as a backup to a dedicated T1 IPSEC VPN. Basically I have 1760 with a T1 internet connection running a typical IPSEC VPN back to a central hub, using GRE and routing protocols to detect failures. I have currently implemented ISDN DDR back to the main hub, but would like to eliminate long distance charges on my ISDN line. I can have a dialup ISDN account with the ISP for backup, but I am not sure how to setup the router to have a failover IPSEC VPN on the ISDN internet connection when the T1 goes down. Any one have a similar scenario? I have successfully made the IPSEC VPN work over the ISDN dialup, but I'm not sure on how to set it up as a failover secondary connection.
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...