Why would wireless routers become less reliable over time?

I've been curious about this for awhile now. I don't know if I'm seeing a real pattern or not, but having worked with many home office/small office wireless routers for a few years now, I've noticed that the heavier the traffic is in the environment, the less reliable they become over time.

Desktops become clogged with malware and innumerable user installed programs, but a router just sits there "untouched" - pretty much the same as the day that you pulled it out of the box - other than occasional firmware updates.

I'm not talking about total failure, but the frequency that they become unresponsive. A quick reboot and users can connect again, but over time those reboots happen 3-4 times/wk rather than once a month or once every 6 months.

I guess typically over time bandwidth demands also go up - more users connecting or downloading/streaming more things, but in a couple environments where usage rates stay relatively constant, it still seems to happen.

I would think that the hardware would basically either work or not rather than a general decline. What components, hardware or software, might be causing this or is it a made up pattern in my head?

Edit: Not to make this question more complicated, but sometimes it's just the wireless access that stops. The wired computers continues to work just fine. Hopefully, some others can confirm that they've seen this, too.

Solution 1:

In my experience, it's been heat. There's not a lot of airflow in these devices (no fans) and they're usually tucked up in closets or somewhere with no airflow. My last wireless router was screwed into a wall high in a closet. It lasted a year, and the case was always warm. When I replaced it (with the same model of linksys), I put a fan up there with it and the current one has lasted three years.

Solution 2:

Many of these small devices have a hard time with power sags and brownouts. If the power goes completely out (and stays off for a few seconds), then comes back on, things are OK, but other power problems cause lockups or other strange problems (returns pings, but won't route).

When we moved into our house 8 years ago, our power was rock solid for several years and my Linksys WRT54GL never missed a beat. During the last few years, there has been a lot of nearby construction and power sags and outages have become relatively common. If the lights flicker, often my computer will keep going, there is a 50% chance that the coffee maker's clock will reset, but there is about a 90% chance that the WRT54GL will lockup. I assume a UPS would fix the problem, but just I haven't gotten around to trying it. At some point, the wall transformer failed. It seems that the WRT54GL has been better since it was replaced.

Also: Many of these devices run Linux (mine runs openwrt). The more traffic you push through a typical Linux device, the more likely you are to run out of some type of kernel resource (slots to keep track of TCP or NAT sessions, process handles, etc.). Rebooting the device will reset the tables. We had this type of problem with Linux based firewalls in our data center. I never was able to track down what kind of resource limit was being hit, but adding RAM helped and finally a substantial hardware upgrade (running the same software) has fixed the problem completely.

Solution 3:

Two reasons heat and age.

1. Inexpensive home routers have very poor heat dissipation, causing lockups and poor transfer rates.
2. Transmitters wear out over time (probably due to item #1)

Every WiFi router I've owned has lost the transmitter eventually (usually long before the wired connections failed.) You can extend the life of the router by mounting it in a cool dry place. The one in my (nice clean) basement has lasted three years and is still going strong. On top of your (dust covered) TV it will die in 1.