We have an established IPSec VPN between a Cisco 2611 and a Cisco 3005 that seems to be working well and nothing out of the ordinary shows up in the logs. However, users on one end of the link seem to lose their drive connections that are mapped to the server at the other end of the link about every half an hour of inactivity. If they reboot, the connections are restored. I was thinking that the ISP may be dropping the low priority UDP packets that Windows is sending out. My question is whether the ISP router would be able distinguish the nature of the UDP packets, since they are encapsualted within the IPSec ?
Most SPs dont regulate the type of traffic but most certainly theyll see your IPSEC UDP packets as any UDP and wont be able to distinguish the packet from any other. Now if they are running your connection through a firewall that automatically closes unused or inactive connections, then it could drop the tunnel. But it doesnt sound like thats happening, more like youre just losing the mapped drives but the tunnel remains open. Strange issue. Have you talked to Cisco about it yet?
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...