On Internet Speed, Bandwidth Hogs, and Bandwidth Vampires

As an Internet Service Provider, the most common complaints we receive these days are about performance. Typically, these take the form of “the Internet has been getting slower lately”, or “it says I’m connected, but I can’t go to webpages”, or even “my SpeedTest numbers are X, when they used to be Y”. As we investigate these reports (we take all of them seriously!), we do occasionally find a problem – maybe the RF signal strength has dropped and the antenna needs to be re-aligned, maybe there are Ethernet errors which persist even when the router is bypassed, suggesting there is a physical problem with the cabling between the router and the radio. Most of the time, however, what we see is that the connection is just being saturated.

What does that mean? Well, every computer network connection has a certain property called “bandwidth”. This measures the maximum speed at which traffic can flow in each direction. Each time a computer or any other device communicates over the network, it sends a request out to a server, which then responds by transmitting data, and the requesting device usually replies by informing the server how that transfer is going – things like “I got all that, send me the next big chunk” or “wait, I missed a packet – re-send me that one!” As long as there is plenty of bandwidth available for all of the data packets to be sent and received, everything works pretty well. But, with most Internet subscribers these days using wireless routers with lots of devices, each active device connecting to the router is competing for the limited bandwidth resources, and…

When the amount of Internet traffic which is moving in one direction exceeds the total amount of bandwidth available for that direction, the packets have to be prioritized, like traffic merging onto a freeway. If the excess traffic is small or fleeting, the traffic jam rapidly clears up, and the packets can merge, but if the excess traffic is heavy and continuous, everything appears to grind to a halt, especially for the new requests, which are basically trying to merge onto a highway filled with barely moving, bumper-to-bumper traffic. As more and more devices connect to the Internet, and each device expects to use increasingly larger portions of the finite bandwidth, these traffic jams become more and more common. Conducting a Speedtest when this is occurring is not informative, as the Speedtest itself must compete for bandwidth – all Speedtests can do is measure the amount of bandwidth available at the time, and even the fastest Ferrari in the world will only show a low speedometer reading during rush hour traffic on I-35!

While some of these Internet traffic jams can be caused by a bunch of different, reasonably small-scale processes, that is not usually the case. Most of these are caused by “bandwidth hogs” – processes which greedily use every bit of available bandwidth, and would happily use more if they could. Even worse are the “bandwidth vampires” – processes which are using up all your bandwidth, but are not obviously active. These may be running in the background on a computer or other device, maybe on a device which is not attended, or even one which appears to be off! These can be very hard to track down, but can have a huge impact on the Internet performance for everyone in the home.

The most common culprit is streaming video. Modern streaming video systems are designed to take advantage of high-speed connections commonly found in the big cities, where most customers connect to the Internet using very fast cable modems or even faster fiber-optic connections, so there isn’t a big pressure to make the streams efficient enough to get by on limited bandwidth. Some services of this nature, such as NetFlix, do allow users to limit the amount of data per stream, but the vast majority are specifically designed to use as much data as they can, and dynamically adjust the bandwidth used to maximize picture quality, often up to full-HD streams, which can run up to 10 Mbps if the bandwidth is available. Other video services may download very large video files to watch at a later time. If you have any of these devices connected to the Internet in your home, they could be using up your bandwidth even if you don’t think they are on! Roku, Amazon Fire, Slingbox, Tivo’s Roamio, Apple TV, many DVD or Blu-Ray players, DirectTV or Dish Network boxes, most video-game consoles, phones, tablets, and many other devices are all capable of downloading video off the Internet. Such downloads may be happening even when the device does not appear to be in use.

Some other common bandwidth hogs include:

  • Cloud backup services – backing your data up is very important, but these programs and services must create a full backup of your system before they can take advantage of “data deduplication” methods which reduce the daily bandwidth required. This initial, full backup will try to use all of your upload bandwidth, de-prioritizing your requests to check e-mail or go to web pages, and can last for days. The simplest solution, if you wish to use a system like this, is to tell the software or service to only back data up at night, when everyone is asleep. This will cause the first phase to take longer, but it will give you the benefit of the backup without making it impossible to use the Internet while it is taking place.
  • Large file downloads: As with streaming video, the proliferation of some very fast Internet connections serving the 80% of Americans who live in large cities has taken away the pressure felt by software developers to make efficient use of space. As a result, a large, state-of-the-art computer game may require you to download more than 10GB of data to play. Even system software and applications have experienced a large degree of code-bloat. These big software houses also use CDNs capable of pushing very large data streams to lots of users, easily enough to completely saturate your connection’s download capability while the download is in progress. These are not limited to computers – phones, tablets, and consoles may also download large files, and again, these can do so while unattended or even in sleep mode, when they appear to be off.
  • File-sharing: While there are some legitimate uses of file-sharing applications and protocols, many people erroneously think they are anonymous, and use them to violate copyrights, moving around or sharing huge files, which not only clog your Internet connection, but could also result in costly legal proceedings. Even the completely legitimate uses of these tools can easily saturate bandwidth in both directions, preventing anyone else in the home from using the Internet. What’s worse is that these apps typically run in the background all the time, even when no one is at the computer. These are often Bandwidth Vampires.
  • Unauthorized users: OK, this is probably rare for our subscribers, many of whom live a good distance from their nearest neighbor, and most of whom have already secured their routers, but if you are running an unsecured wireless router, anyone within range can access anything on the Internet using your connection. Luckily, the way to prevent it is a simple matter of requiring a passkey to access the router. A fairly simple WPA2-PSK key of at least 9 characters (avoiding common dictionary words) and using a mix of cases plus numbers and punctuation, is effectively un-crackable.

How can we tell if this bandwidth saturation is happening or what device is responsible? Ah, that’s a tough question. Unfortunately, most routers don’t have little meters on the front, telling everyone how much data is passing through them in real-time. Some computers can be told to display the amount of Internet traffic they are utilizing, but as we’ve noted, much of the Internet activity which impacts others in the home may be from devices which aren’t computers. Our support staff has tools which can monitor most of our customers’ connections (except in certain rare circumstances), but we can’t tell which device in the home is responsible, just how much data is coming from or to which IP addresses and what protocols are involved. When it comes to finding the malefactor, a simple process of elimination can help – going to each and every device which can connect to the Internet, and shutting it down completely (note: sleep mode is not the same as off!), then noting the impact on performance, should catch the culprit, assuming the issue isn’t from some device whose existence isn’t known.

More of a concern is “what can be done about the issue?” After all, if one device in the home is using all your available bandwidth, and you decide to switch to a more expensive plan which increases your bandwidth, what’s to say that culprit won’t simply scale up its bandwidth demands under the new plan and leave you in the same pickle as before? There really are only a few useful strategies which work:

  1. Manual control: This is pretty straightforward. For this to work, people in the home must coordinate bandwidth usage – if someone needs the Internet for work or school, others may have to wait to watch videos or play games on the internet. Just like a typical water heater wouldn’t have enough hot water for everyone in a family of five to each take a long, hot shower right after the other on a Monday morning, it may not be possible for everyone to simultaneously use the Internet as though they lived alone. It takes some getting used to, but it can work.
  2. Automatic control: Most modern routers support Quality of Service settings which can adjust the priority for certain devices’ Internet usage. Just Google “QoS settings” and your router’s model number, and you’ll see if you can program your router to assign the highest priority to certain devices or types of traffic and lower priority to others. This can be used to ensure that a particular computer or certain programs (like Skype) will always get top priority, for instance. Other steps in this strategy include configuring limits (where possible) on certain tasks. As I mentioned, NetFlix does allow users to set the Video Quality to specific settings¬†which reduce the amount of bandwidth required. Other video services or devices may allow such control, as well. Cloud backup systems typically allow users to configure times during which they upload to the cloud, and some allow the maximum data speed of the software to be controlled, too. Even many file-sharing applications allow you to limit the number of simultaneous connections or the amount of bandwidth they are permitted to consume.
  3. More bandwidth: As I mentioned, by itself, this one won’t fix all problems. If not controlled, bandwidth hogs can use up all the extra bandwidth assigned to a connection and still want more. But, when you combine an increase with the other two strategies, you may find the extra breathing room afforded by a bandwidth increase will also increase your satisfaction with the usefulness of the Internet.

I hope this gave a bit of insight into a rarely-discussed aspect of the Internet. If you think this might be happening with your connection, give us a call when the problem is occurring, and we can take a look!