Netopia 4753 manual About Pptp Tunnels, Summary

Virtual Private Networks (VPNs) 12-3

In either case, the Netopia Router wraps, or encapsulates, information that one end of the tunnel exchanges with the other, in a wrapper called General Routing Encapsulation (GRE), at one end of the tunnel, and unwraps, or decapsulates, it at the other end.

■IPsec stands for IP Security, a set of protocols that supports secure exchange of IP packets at the IP layer. IPsec is deployed widely to implement Virtual Private Networks (VPNs). IPsec supports two encryption modes: Transport and Tunnel. Transport mode encrypts only the data portion (payload) of each packet, but leaves the header untouched. The more secure Tunnel mode encrypts both the header and the payload. On the receiving side, an IPsec-compliant device decrypts each packet. The Netopia 4753 supports the more secure Tunnel mode.

DES stands for Data Encryption Standard, a popular symmetric-key encryption method. DES uses a 56-bit key. The Netopia 4753 offers IPsec DES encryption over the VPN tunnel.

Configuring the Netopia Router for use with the different protocols is done through the console-based menu screens. Each type is described in its own section:

■About PPTP Tunnels on page 12-3

■About IPsec Tunnels on page 12-7

■About ATMP Tunnels on page 12-19

Your configuration depends on which protocol you (and the router at the other end of your tunnel) will use, and whether or not you will be using the VPN client software in a standalone remote connection.

Having both an ATMP tunnel and a PPTP export is not possible because functions require GRE and the router’s PPTP export/server does not distinguish the GRE packets it forwards. Since it processes all of them, ATMP tunneling is impaired. For example, you cannot run an ATMP tunnel between two routers and also have PPTP exported on one side.

Summary

A Virtual Private Network (VPN) connects the components of one network over another network. VPNs accomplish this by allowing you to tunnel through the Internet or another public network in a manner that provides the same security and features formerly available only in private networks.

VPNs allow networks to communicate across an IP network. Your local networks (connected to the Netopia Router) can exchange data with remote networks that are also connected to a VPN-capable router.

This feature provides individuals at home, on the road, or in branch offices with a cost-effective and secure way to access resources on remote LANs connected to the Internet with Netopia Routers. The feature is built around three key technologies: PPTP, IPsec, and ATMP.

About PPTP Tunnels

To set up a PPTP tunnel, you create a Connection Profile including the IP address and other relevant information for the remote PPTP partner. You use the same procedure to initiate a PPTP tunnel that terminates at a remote PPTP server or to terminate a tunnel initiated by a remote PPTP client.