RuggedCom RX1000, RX1100 manual Configuring Generic Routing Encapsulation, GRE Fundamentals

RuggedRouter™ User Guide

Chapter 17 – Configuring Generic Routing Encapsulation

Introduction

This chapter familiarizes the user with:

∙Enabling/Disabling GRE

∙Viewing GRE Status

GRE Fundamentals

The RuggedRouter is able to encapsulate multicast traffic and IPv6 packets and transport them through an IPv4 network tunnel.

The GRE tunnel can transport the traffic through any number of intermediate networks. The key parameters for GRE in each router are the tunnel name, local router address, remote router address and remote subnet.

Router 1		w1ppp	w2ppp		Router 2
		172.16.17.18	172.19.20.21
eth1	192.168.1.1			192.168.2.1		eth2
192.168.1.0/8					192.168.2.0/8

Figure 146: VRRP Example

In the above example, Router 1 will use a GRE tunnel with a local router address of 172.16.17.18, a remote router address of 172.19.20.21, and a remote subnet of 192.168.2.0/24.

Note: If you are connecting to a CISCO router, the local router address corresponds to the CISCO IOS “source” address and the remote router address corresponds to the “destination” address.

You may also set a cost for the tunnel. If another method of routing between Router1 and Router2 becomes available, the tunneled packets will flow through the lowest cost route. You can optionally restrict the packets by specifying the local egress device (in the case of router1, w1ppp).

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