Mixing and Matching Network Technologies

Networks can easily mix and match topologies within the confines of a single network technology, but interconnecting network technologies requires more sophisticated equipment. Here's a brief rundown of the issues:

• Interconnecting different media in a particular network technology: Most vendors offer simple devices (that is, repeaters and bridges) to interconnect network segments that use different types of media, such as twisted-pair (10Base T) and coaxial (10Base2) cable for Ethernet. Windows Server 2003 can handle multiple network interfaces, each with a different media type as well.

• Interconnecting different network technologies in a network: As long as the protocols stay the same, routers or brouters can handle the job, such as interconnecting token-ring and Ethernet segments. Likewise, the built-in routing capabilities of Windows Server 2003 allow it to function as a router to interconnect different network technologies with ease. It just can't do those things as quickly as special-purpose, high-end routers, such as those from Cisco Systems and Nortel Networks.

• Interconnecting fundamentally different protocols or applications: Gateways shine when fundamentally different protocols or applications must exchange data. This exchange involves considerably more effort and intelligence than the lower-level services that bridges and routers provide. However, gateways must also be sensitive to many more nuances and levels of functionality than other devices. This probably explains why they're more prone to problems than other choices.

REMEMBER 

In its TCP/IP settings, Windows 2003 asks for the address of a gateway. In this particular instance, Windows 2003 is using the term gateway in a different sense than what we've been discussing here. When configuring its TCP/IP settings, Windows 2003 considers the term gateway to be synonymous with the term router and, in fact, points to a device that can forward packets not directed to the local cable segment for delivery to the outside world. Be sure to keep this in mind when you configure TCP/IP for Windows 2003!