We’ve all been there: one minute everything at work is running just fine, and the next minute you can’t get websites to load, or your file upload or download speeds slow to a crawl.

When this happens at home after work, it’s an inconvenience — and most of the time rebooting your router, modem, or gateway solves the problem. But at work? Internet speed issues or network bottlenecks can seriously interfere with your employee’s productivity and profitability of the company.

Today we’re going to share 7 common causes for network bottlenecks — and we’ll do our best to use plain, nontechnical language as we go. But first, let’s start by explaining what’s going on when network speeds plummet.

What Is a Network bottleneck?

A network bottleneck is any situation where the flow of data gets constricted, limited, or slowed. It’s a blanket term, in a way, covering all the various reasons why you’re not getting what you need out of your internet connection.

Think about your home internet for a minute. Sometimes when you have issues, you call or chat with your service provider, and they tell you that the problem is at its end and they’re working on it. That’s a network bottleneck: something somewhere at your ISP is limiting data flow (imagine data as water running through pipes, and that water just hit a partial blockage).

Sometimes the problem is at your house: if you’re on the budget plan but 3 TVs and 5 mobile devices are all trying to stream Netflix, you’re going to use up your bandwidth (the incoming water pipe is at full blast, and you’re still not getting enough water). Or you might have a rogue device gobbling up most of your bandwidth for no good reason, giving you the same result.

All of these concepts are network bottlenecks. But if you want to fix or avoid the symptom, you have to know the cause first. So, with that in mind, let’s look at 7 common network bottleneck scenarios in the work environment.

1. Firewall Size

A firewall blocks traffic coming in and out of your network, giving your IT department control over what’s allowed in and out. They can get awfully technical from there, but this definition will work for our purposes.

Firewalls come in different (metaphorical) sizes, which can be measured in total number of users or total amount of throughput. Kind of like our Netflix-at-home example, if you try to push more data through your firewall than it can handle, you’ll hit a network bottleneck.

Maybe you have plenty of bandwidth (speed) from your internet service provider — it doesn’t matter if your firewall can’t match that speed.

2. Problems with Network Switches

If your building and your IT infrastructure are more than a few years old, you might need to check on several things. The network switches installed throughout might be older 10/100 switches, which max out at 100mbps. Your actual network connection might be way, way faster—but it gets bottlenecked at these switches.

As infrastructure ages, the ports on your switches (including the ethernet ports your computers plug into in the wall) can go bad, degrading performance.

3. Insufficient or Outdated Modem

The modem you’re using (at home or in the office) could be another chokepoint: it doesn’t matter how lightning-fast a connection you’re paying for, you won’t see anything move faster than what your modem is rated for.

The good news is that this is a relatively easy fix. It’s not difficult to find out what bandwidth your modem can handle (or what bandwidth you’re paying for). If the first is lower than the second, it’s time to upgrade.

4. Bad or Insufficient Cabling

Along the same lines, your network cabling — the wires running inside wall conduits at your office or connecting your modem and router at home — is also rated for a specific max speed. Older buildings may be equipped with outdated Cat5 cabling (or slightly newer Cat5e). If your internet speeds are gigabit or higher, you really want to look into cat6 or even cat6a cabling.

These all look virtually identical, so you may need technical assistance in identifying what you’re currently using.

5. Low-Speed VoIP Phone Pass-through Ports

Sorry if we’re sounding like a broken record, but the network ports on your VoIP phones can also be the source of a network bottleneck.

If your office has switched to VoIP phones (and it probably has), you likely have a physical handset at your desk that sits between your network cable and your computer. The network connection “passes through” the VoIP phone.

Ordinarily, there are no issues. However, some of those ultra-cheap VoIP phones are actually quite a problem. You might need to investigate the speed that those pass-through ports are rated for: if it’s lower than your connection speed, you’ve likely identified your network bottleneck.

6. LAN Overload

This one isn’t relevant at home or in a small office, but if you’re at a larger office, be aware that it’s possible to overload your local area network (LAN) with too many physical devices. Once you reach a certain number of IP devices, you’ll get better results by segmenting them out to separate LANs.

To use the water pipe analogy, not every house in a city can possibly connect to a single massive trunk line. A street or a neighbourhood might all be connected on a line that then connects to a main line, and so on. Segmenting groups of houses or businesses adds resiliency and balances the system.

In a large office, think of all those connected devices as houses, businesses, and neighbourhoods.

7. Old Access Points

Far and away the most likely network bottleneck is Wi-Fi. It is inherently not as fast, consistent, or stable as wired internet. Even worse, old Wi-Fi access points were never built to handle modern internet speeds, so they cap users far below their actual bandwidth.

Older devices can even slow down networks when they connect to Wi-Fi. A smart Wi-Fi system like Unifi helps to mitigate this problem.

We Are Here to Help

We hope this guide has helped you to isolate the cause of your network bottlenecks. Still, even once you’ve found the problem, many of these are more technical to fix than you might be comfortable trying on your own— especially if they need to be fixed at the scale of an entire office.

If you could use help identifying the problem or implementing the solution, we’re experts that you can trust. Reach out to our team today to schedule a consultation!