I haven't got the exact decode of the 0x0 proposal, but I would start on checking the defined transform proposal on the router against the peer, ie esp-des, esp-hmac-md5 and also the lifetime. Does the peer understand the lifetime in secs or only in kb, or both?
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...