Dealing with slowing networks

Sometimes troubleshooting internet issues leads you through unusual twists and turns and sometimes it is just about checking on the basics. In the last week I have been asked to fix connectivity for two different businesses. When I hear that request my curiosity gets the better of me; I really need to find out the answer to “what is leading these people to ask for this service?”. I confess that each case is unique but it usually revolves around network or internet speed issues.

A quick history of networks and the internet might be helpful here. Way back when, in the age of dial-up service, we used coax cable in various topologies (rings, stars, chains, etc.) and networks transmitted data at amazing speeds of 20k (thousand bits per second) all the way up to 2m (2 million bits per second); this was okay because printers could produce up to 30 characters per second and modems (dial-up devices used to bring internet access to your network or a single machine) were capable 120 baud (12 words per second = approximately 120 bits per second) , 300 baud, 1200 baud (a fairly common speed at one point) all the way up to 9600 baud (realistically somewhere between 480 and 960 characters per second). As networking matured, standards like 10 base 2 and 10 base T took hold and networking speeds outstripped the speed that machines could take in data. Now we use networking based on 100 base T (fast ethernet) and 1000 base T (gigabit ethernet – 1 billion bits per second with one character requiring 10 bits) running on fiber optic or category 5 cable (cat5, cat5e, cat6); and, just for completeness, our modern networks are similar to the old star networks.

Up until recently, the new network speeds were significantly faster than anyone had a use for. Up until recently, most emails were very small (a few hundred up to a few thousand characters at most). Now we have several common technologies that require HUGE amounts of data; digital photographs can be made up of 3 million to 40 million bytes (8 bits in a byte) or more, videos may consume 3 billion or more bytes per hour of video and documents that once averaged 800 bytes per page can now (because they may include photos, graphs, drawings, videos, etc.) use more than 1 MB (mega byte, 1 million characters) per page. The result is that it is now possible for a small office to experience congestion on their network (like traffic at rush hour; everything slows down and may seem to come to a complete stop). To exacerbate this issue we also have a lot more devices that may be using the network and each device can have all kinds of helpful and cherished utilities running that depend on network and internet support.

It is this new tendency to consume great amounts of data and send it over the local network or out into the internet that is a primary cause of network congestion. What I see, all too often, is that most of this is unintended traffic; what I mean by this is that the folks using all of this stuff (bandwidth, or transmission potential) have no idea that they are consuming (demanding) all of this data or any data at all. At least the driver of a car who gets on a main arterial at rush hour has some understanding that they represent one small part of the traffic congestion; computer users who listen to internet radio on their phone (just one of hundreds of examples) while at work have no idea (most of them anyway) that they are using up a measurable percentage of the total internet bandwidth available to the office network (and they are adding to general network congestion on the local network also).

So, how does this affect you? I looked at a home network last week because the client complained of not being able to print on occasion and wanted me to fix the network connectivity. My first look revealed that all was well with the equipment, and that lot of data was being successfully moved by the network. After a few questions about what was included in the network, what it was supposed to do and so on, I realized that I was seeing way too much network traffic for those few pieces of equipment and the tasks that they were intended for. This can have several causes and I attempted to verify or rule out a few of the most common. A damaged network adapter or damaged router (the device that handles routing information from the internet to all devices on a network and between devices on a network) can cause this kind of extreme traffic buildup. After a couple tests and component replacements this was ruled out; so on to seeing if the traffic was intended traffic and just far greater than the client (or I) suspected; but I was able to rule that out with a few more tests. I then asked the router (to be truthful I started this early on but let it run for a while and then checked on it at this later stage) where the traffic was going and what was the nature of the traffic. It was at this point that we (the client and I) learned that several smart phones (in the house, innocently being used by household members) were responsible for 95% of the traffic on the network and were keeping the network at 95-100% of capacity. The solution in this specific case was simple and some were happy.
In another case, this week, I had a similar request and this time I found that a computer had been set to back itself up to the cloud, daily. Whenever this computer had some idle time it continued the process of backing itself up and the internet appeared to completely stop for everyone else in the office. Adjustments were made to the backup policies on that computer (part of many of the better on line backup services) and it was set to only backup things that changed and the problem disappeared.

When your internet performance suddenly changes for the worse (who complains when it suddenly gets better?), it can be an issue with your provider or it can be a change in your habits, it can be a sign of viral or malware activity, or it can be some unintended traffic plugging everything up. It can also be the result of interference with wireless transmissions, damage to a network cable or interface, etc.
What ever the cause or causes, it can be very frustrating and it may be one of those problems you look to a consultant or network professional for help with; this is another case where practice really speeds up the process of identifying and fixing the problem.