I setup cisco 871 as a vpn client connecting to 3005 concentrator. (the client has a private address). The connection is successful. Right after the tunnel is up I can ping a host on a remote network (behind 871). But when I stop the ping for about 20 seconds I cannot resume it, although the ISAKMP and IPsec SAs are still there (on both router and concentrator).
I solved the problem with isakmp keepalive 10 periodic command on the router, although I am not happy with the solution. It is normally used for DPD when backup servers are configured. Why do I have to use it in this case?
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...