January 27, 2014 6 Comments
A bad WiFi network is always painful. If you are playing with an online game and your network has a big latency, enemy can defeat you easily. Sometimes you just disconnect due the high lag especially when you could win (don’t forget Murphy’s law). If you want to copy files on the local network, it can be incredible slow. If you want to play a video, it will be low quality or will be paused from time to time.
So if you encounter the above problems, and you know that your Internet access is good, it’s time to verify your WiFi.
First of all, you have to check the general WiFi parameters. In the “old days”, you should have used a laptop, but nowadays, there is a better option. You can use your mobile or your tablet to analyze your network. The easiest way is to download a WiFi Analyzer application from Google Play, and run it. In the following, I will use my WiFi Analyzer application but of course you can use any other analyzer application too. You can download this app from Google Play. Detailed guide is available here.
Now I will tell you several information about the WiFi networks and suggest you possible solutions.
So let’s begin and start the analyzer application:
As you can see, it displays several information on the dashboard (the most important values are rounded by red circles). In the next chapter, I will explain them.
Understanding the WiFi parameters and the problems they can cause
This is the power of the received signal. The weakest the worst. Based on my experience, a good signal is always higher than -75 dBm. For example if the signal strength is -50 dBm, it is good but if -90 dBm or lower (don’t forget, we speak about negative values), it’s bad. If this is the case, something blocks the signal, for example a wall or a furniture. You should put your router on a different place until you find the best signal strength. If you are too far from the router, a better antenna may solve this problem (the most antennas can be replaced). Furthermore, don’t forget to check the antenna contact, it may be wrong.
This is the theoretical current speed supported by your device. In the best case, it should be the same speed that your router supports. For example if your router supports 802.11n protocol with 150 Mbps and your mobile device also supports this protocol, you should see this speed as current link speed. The lower speed can be caused by several reasons:
- Your router is set to compatible mode. For example only b/g protocols are enabled however it supports “n” mode too. Always set it to the highest protocol that your devices support. For example set it to b/g/n mode. Warning: do not set it to only “n” mode except if all of your devices support this protocol! If a device does not support this protocol, it will not be able to see this wifi network.
- Your mobile devices does not support the protocol belongs to this speed. For example, the highest speed supported by your router is 802.11n with 150 Mbps, but your mobile supports only 802.11g with 54 Mbps. In that case, the maximal link speed can be only 54 Mbps and you can’t change it without replacing your mobile.
- The signal strength is weak. If both your router and mobile device support the same protocol with the same speed but you see a lower speed, then usually the low signal strength is the reason. In that case, just read again what I read above at the signal strength topic.
Obviously, it’s your decision if the displayed speed is acceptable for you or not. For example if you are using your WiFi network only to use Internet, and the speed of your Internet access is 6 Mbps, link speed can be fine above 12 Mbps.
Good to know:
- The link speed is not the real network throughput! In fact, the maximal network throughput can be only the 50-70% of the link speed thus your devices will never achieve the displayed link speed. This is the limitation of the wireless protocol.
- This bandwidth is shared for all clients and not per client based. For example if the bandwidth is 20 Mbps and you have two devices, the download or upload speed can be only 10 Mbps/device if they are using the network at the same time with maximum speed.
- Make sure that the link speed is at least the double of the speed of your Internet access. If it is lower, your WiFi network can become a bottleneck and you may not be able to use the full bandwidth of your Internet access.
Tip: If you want to check the real speed, you can use my WiFi Speed Test application. It measures your WiFi network throughput. I know this is a little bit complex application, but it’s worth the time.
This is the latency time of your access point (router) in ms. If someone generates hard network traffic, this value will be high so you can detect it easily. The higher latency can cause problem in online games, so be careful if the latency is higher than 40-60 ms (it depends on the game you are playing with).
Now you know how to understand the most important WiFi properties and the common problems that the bad values can cause. Don’t forget, there are correlations between the above values so if something is wrong in your network, it will be indicated by several values. If you don’t want to understand what these values mean, my analyzer application can translate them to a human “language”. Just click on “Analyze” button and you will see red cross if something is not working properly (or green pipe if it is ok).
Best place for router
Well, this is always a good question. Usually there are two general rules:
- place your router as close as possible to your device
- if you have several devices around your flat, just imagine a big sphere around your devices and put the router on the middle of this sphere.
Don’t forget, these are just general rules, but I’m afraid, nobody can tell you where the best place is. It depends on the type of the walls around your devices, the number of the walls between the router and a device or if there are any windows or doors instead of walls.
So if you want to find the best place, you have to make several tests. As I already mentioned you, there is an application called WiFi Speed Test. Using this application, you can measure the real network throughput when you are moving your router and using the measured test results you can find the best place where the network throughput is the best for all of your devices. You can download it from Google Play. Detailed guide is available here.
Overlapping networks can cause interference that will slow down the speed of the your network. I don’t want to bore you with the hard technical details: just imagine that several people are shouting with each other in a small room at the same time. You can imagine that nobody will understand what the others say due to the “interference”. Something similar happens in the case of wireless networks when they use the same frequency. In fact, the neighboring frequencies have also overlapping effect. If an analyzer detects overlapping networks, you should choose another frequency. This can be set in your router, the name of this option is “channel”.