Dial Vpn Network Concepts; What Is Tunneling - Bay Networks Baystream 7 Configuration And Troubleshooting Manual

This chapter describes important Dial VPN network functions to help you
understand the network's operation. Among these are how a data packet sent from
a remote node using the point-to-point protocol (PPP) moves through a Dial VPN
service provider's network to a corporate or "home" network via a frame relay
connection. It also explains how the Dial VPN tunnel forms a path to move data
quickly and efficiently to and from the remote node through the Dial VPN service
provider's IP backbone network.
Dial VPN uses Mobile IP and Generic Routing Encapsulation (GRE) technologies
to provide a secure pathway for remote users to exchange data with their corporate
home network. Regardless of where a remote node is located, it can dial in to its
Dial VPN service provider and connect to the home network.

What is Tunneling?

Tunneling is a way of forwarding multiprotocol traffic and addresses from remote
nodes to a corporate network through a Dial VPN service provider's IP backbone
network. GRE is the tunneling mechanism. It takes an incoming packet of any
protocol, wraps that packet's contents in a GRE packet, then routes the
encapsulated packet over the Dial VPN IP network.
Dial VPN dynamically creates a tunnel when it connects to the remote node's
home network. The tunnel endpoints are the NAS and the gateway on the Dial
VPN service provider's network. Once the tunnel is created, packets from the
remote node and the corporate home network flow through the tunnel. Each tunnel
supports one user. The tunnel exists as long as its user remains connected.
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Dial VPN Network Concepts

BayStream Multiservice Software Version 7.2
Chapter 2
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