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Quality of Service

In a perfect world, QoS would have been built into the Internet from the start. Then, inconsistent bandwidth utilization, jittery latency, packet loss and greedy applications wouldn't worry us.

But the world isn't perfect, so for streaming media, such as voice over IP, you need to ensure low and steady latency as well as a specific amount of bandwidth. Applications like FTP and Web traffic may not be sensitive to latency, but they can eat up bandwidth like crazy. An oversaturated network causes packet loss, inefficient data transfer and snarky end users.

QoS can be achieved in several ways. Enabling compression and buying more bandwidth are the simplest solutions, but may only delay the inevitable. More effective ways to stop users from clogging your pipes are to use Type of Service, Integrated Services, Differentiated Services, queuing or TCP rate-shaping. Of these, only the latter two are effective at controlling data sent across the Internet. The rest are best for internal LAN QoS or between partners with service agreements.

Don't fall prey to the philosophy of buying more bandwidth whenever you run short. By implementing a few simple QoS policies, you can tame bandwidth-hungry applications in favor of mission-critical protocols. And because QoS capabilities have found their way onto many pieces of network infrastructure, the cost to enable QoS could be minimal.