Packet Shapers – CompTIA Network+ N10-006 – 1.1

There are many different applications on your network, and each application may have a completely different set of priorities. In this video, you’ll learn how packet shapers can allow these diverse applications to peacefully coexist on our networks.

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We have many different devices on our networks these days. It’s not just a computer that’s on your desk. We have mobile phones. We have laptop devices. There’s tablets. There’s all kinds of network-able machines, and there’s all kinds of applications running on those network-able machines.

It may be a very important application you use in your organization. Maybe they are streaming video you’re watching, like this video series. Maybe there’s audio over voiceover IP so you can have a conversation with someone over the phone. And each one of these applications have a different set of requirements.

The voice communication needs to happen in effectively real time. The streaming video that you’re watching probably has a buffer, so there’s a little bit of a leeway as far as the type of traffic stream you have to worry about there. And if you’re using a database, you would want to have a relatively fast response time from that database.

Some applications, therefore, we might consider to be more important than others. That voice communication, because of its real time function, may be more important than the streaming video that you’re watching. But how do you manage your network so that the voice communication has more of a priority than something like a streaming video?

Well, to do that, we use something called quality of service. This quality of service functionality is provided through devices called packet shapers or traffic shapers. These are devices that allow us to take the application in use and limit the data rates or bandwidths that those applications are going to use. This allows us to set a more important priority for something like voiceover IP and put the streaming media more on a lower priority than that.

This is something where you may configure in a router or a firewall, or perhaps it’s a standalone device that’s designed to do quality of service. And it’s usually in line with all of the traffic that’s going in and out of your organization. This is a screenshot from the QoS priority rule list that’s inside of my router.

This is very simplistic quality of service, but you can see the ideas there where an IP phone might have the highest priority for phone or Vonage IP, or something like Google Talk would be set maybe highest. But down at the normal level, we see things like a file transfer or email transfer. This means that my voice communication can be crystal clear without any type of interruptions, and at the same time I can still do all of the file transfers and data transfers without either of them creating a problem.