I have the same problems on my 1812 router and on my 871 router. I have IOS Version c870-advsecurityk9-mz.124-15.T10.bin runnning.
Which IOS do you have active ?
Since this IOS is installed I have the problem that VPN Tunnel is showing active(show crypto isakmp sa) but from time to time packets are encrypt, on the other site not decryp. Do you also running this behaviour ?
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...