Planning For Dial Vpn; Dial Vpn Overview - Bay Networks Baystream 7 Configuration And Troubleshooting Manual

Bay Networks
secure dial access services for corporate telecommuters, mobile professionals, and
users in remote branch offices. Dial VPN provides switched connectivity to virtual
private networks (VPNs), based on the Internet Engineering Task Force (IETF)
specification Mobile IP. Corporate customers can subscribe to this service for
remote dial access to virtual private networks or to the Internet over telephone
lines.

Dial VPN Overview

Dial VPN, formerly known as BayDVS, offers remote users simple and secure
access to virtual private networks and the Internet through a mechanism known as
a tunnel. A tunnel is a secure, virtual, direct pathway between two endpoints. The
process of encapsulating and decapsulating the datagram is called tunneling, and
the encapsulator and decapsulator are considered the endpoints of the tunnel. In
this case, a tunnel is the pathway between the network access server (NAS) that
receives the remote user's call and the gateway that connects to the remote user's
home network through a frame relay network. Dial VPN dynamically establishes
and removes tunnels as needed.
Dial VPN encapsulates multiprotocol data within an IP datagram using the
Generic Routing Encapsulation (GRE) protocol, customized for Dial VPN. It then
sends the encapsulated packets through bidirectional IP tunnels that exist between
a remote access server or concentrator (NAS) and a Dial VPN gateway over the
service provider's IP routed backbone. The gateway, in turn, maps a route from
the tunnel endpoint to a frame relay permanent virtual circuit (PVC) on the user's
home network.
115623B Rev. 00
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Dial Virtual Private Network Services (Dial VPN) provides
BayStream Multiservice Software Version 7.2

Planning for Dial VPN

Chapter 1
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