Virtual Private Networking; Figure 1 Typical Pdn - Nortel Contivity 1100 Configuration Manual

26 Chapter 1 Overview
Nortel VPN Router access allows remote users to dial in to an Internet Service
Provider (ISP) anywhere and reach corporate headquarters or branch offices. The
Nortel VPN Router provides remote users access to corporate databases, mail
servers, and file servers.

Figure 1 Typical PDN

The Nortel VPN Router allows ISPs to take over the role of point-of-presence
(POP) providers of modem access. It improves performance while lowering
overhead, which translates to significant corporate savings.

Virtual private networking

A VPN is a private data communication channel that uses a public IP network as
the basic transport for connecting corporate data centers, remote offices, mobile
employees, telecommuters, customers, suppliers, and business partners.
Physically discontiguous networks are made to appear logically connected and
contiguous.
A remote access VPN service requires the creation and operation of a secure
tunnel between client software on a remote device, such as a PC, and host
software on a Nortel VPN Router.
Figure 2 on page 27
NN46110-500
Figure 1 shows a typical packet data network (PDN).
shows examples of VPN services.