Chapter 4: Planning, Implementing, and Maintaining a Routing Strategy

Introduction

In the preceding chapter, you learned about the TCP/IP protocols and how to set up a TCP/IP infrastructure. One of the biggest advantages of TCP/IP as a network and transport protocol stack is its capability to route packets between different networks or subnets. Dealing with routing issues is an important part of the job of a Windows Server 2003 network administrator for a typical medium-to-large size network. In this chapter, we first review the basics of IP routing, including the role of routing tables, static and dynamic routing, and routing protocols such as Routing Information Protocol (RIP) and Open Shortest Path First (OSPF).

You’ll learn to use the netsh commands related to routing, and then we’ll show you how to evaluate routing options. This includes selecting the proper connectivity devices; we’ll discuss hubs, bridges, switches (Layer 2, 3, and 4 varieties), and routers. We’ll look at how you can use a Windows Server 2003 machine as a router, and how to configure the Routing and Remote Access Service (RRAS) to do so.

Next, we look at security considerations related to routing. We’ll show you how to analyze requirements for routing components from a security-conscious point of view, and we’ll discuss methods of simplifying the network topology to provide fewer attack points. This includes minimizing the number of network interfaces, the number of routes, and the number of routing protocols. We will also discuss router-to-router virtual private networks (VPNs), packet filtering, firewalls, and logging levels.

Finally, we cover how to troubleshoot IP routing issues. We’ll identify troubleshooting tools and take a look at some common routing problems, including those related to interface configuration, RRAS configuration, routing protocols, TCP/IP configuration, and routing table configuration.