Have you seen or read about how doctors are performing surgery over the Internet? Do you ever wonder what would happen if someone in the doctor’s office started downloading a big file from the Internet in the middle of surgery?
If the doctor setup their network correctly and used the latest Quality of Service (QoS) equipment, the answer is that nothing would happen to the surgery, but the file would download a little slower than usual. Tweaking your settings to get a faster internet speed won’t alter you QOS settings so I will explain what to do.
What Quality Of Service Does
There are a lot of different types of quality of service. The simplest is buying more Internet bandwidth from your local internet company than you would ever use so all of your computers can use as much bandwidth as they want. In most places this isn’t feasible—a “fat pipe” can cost hundreds or thousands of dollars a month. For example in some places in Australia there are no options to upgrade your internet service, you have to take what you can get.
More complex quality of service schemes are used by large organizations—like hospitals—to prioritize their traffic across parts of the Internet. But in between simple and complicated is an easy to setup quality of service scheme that almost anyone can use.
Router based quality of service doesn’t change how your traffic travels over the Internet and it can’t give you more bandwidth. What it can do is prioritize traffic on your home network so that important traffic—like voice-over-IP phone calls and online games—gets transmitted before unimportant traffic—like the 150 GB bittorrent file with all 29 seasons of the various Star Trek TV shows your son is currently downloading.
Now you could prioritize your traffic yourself—you could make sure you limited the bandwidth of your bittorrent download so that there was always enough spare bandwidth for a phone call, but this has two disadvantages.
First, you’d be wasting bandwidth whenever you weren’t making a phone call. You probably pay a fair bit of money for your Internet connection, so why not get the most out of it?
Second, you’d have to manage every application separately. That’s easy if you have only one computer in your house, but what if everyone in your house has their own computer? Try convincing your teenage son not to try downloading Star Trek a little bit faster.
Quality of service runs on your router, so it applies to all of the computers in your house. And whoever controls the password to the router—that’s you, not your son, I hope—controls which traffic has priority.
How To Get Quality Of Service
You need a special router to use quality of service. I say special because it needs special firmware, but these routers are no longer very special—they’re downright common. A search on Amazon.com for “[easyazon-link asin=”B0006TIA0C”]QoS router[/easyazon-link]” in the electronics section turns up 164 items.
One of the things quality of service routers need to do is estimate how much transmission bandwidth you have. They do this by sending a bunch of traffic to your modem and tracking how much of it gets returned. Unfortunately, some routers are bad at estimating how much transmission bandwidth you have—in particular, older Linksys (Cisco) routers perform poorly. My research indicates D-Link quality of service routers are the best.
How To Use Quality Of Service
Most quality of service routers come with a set of default rules that will prioritize voice-over-IP traffic and traffic from popular games. For anything more sophisticated than that, you’ll need to dive in and add your own rules.
Log into your router using its intranet address (router IP Address) and look for it’s “QoS setup” page. Most routers have three ways to identify the traffic you want to prioritize:
- Ethernet Port this is the port (plug) on the back of your router each computer on your network is plugged into. If your son’s computer is plugged into port 1 and your computer is plugged into port 2, you can prioritize traffic that way. Of course, if your son figures it out, he can always just swap the connection. Ethernet ports also don’t work for wireless laptops since they’re not plugged into anything.
- MAC Address this is the unique code that identifies your computer’s network card. You can find a list of the MAC addresses currently connected to the router. On my router, they’re listed on a page called Attached Devices. Using a MAC address also works for wireless cards.
- TCP/IP Port this is the destination port your traffic is going to. For example, almost all webservers use port 80. If you know the ports your software uses, you can set priorities using port numbers. To find the port numbers, you can type the name of the program into Google plus the word “port”. For example: Starcraft port.
Implementing Quality of Service
The first thing I do is identify any devices that require special priority. For example, I used to have a Vonage voice-over-IP telephone device. I like my phone calls to sound clear, so I’d give top priority to the MAC address of the Vonage box.
Next, I’d identify the computers in the house people use to do real work—for example, the computer someone uses as part of a home office. I’d give those computers medium (normal) priority.
Computers belonging to people who did a lot of downloads, I’d give low priority. But for any games played on those computers, I would look up the port numbers and give the game traffic medium or high priority in your quality of service settings.