In relation to the topic - I class a tunnel as a session. A connection between a client and the router using the L2TP protocol.
What you put over that tunnel/session is irrelevant. The table indicates the MAX number of terminated L2TP connections on the device.
So if you have 50 remote users using L2TP - you would have 50 tunnels/sessions. But each one of those users, could have email/server SMB connections internal WEB connections that TRAVERSE the L2TP tunnel/session.
But a LAC can create one tunnel and have many sessions running within the tunnel where each session serves one user.
I agree that over each session users can have connections like email/internal web etc.
If we consider this model one tunnel can support the 50 sessions you mention in the example, which means that it is not necessary to create 50 tunnels.. (or is it?).. And this creates some confusion in cisco limitations...
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...