WiFi Analyzer promo video

Hi guys,

I just created a new promotional video for my WiFi Analyzer and WiFi Analyzer Pro, and I thought I share it with you.


WiFi glossary

News (2016.09.02): WiFi Tips & Tricks

SSID: This is the name of a wireless network. SSID is a case sensitive, max 32 alphanumeric character unique identifier. Example: my-network

Access point(AP): Generally, this is your router. A device that allows wireless devices to connect to a wired network using Wi-Fi, or related standards.

AP capabilities: This is the security level of the AP. For example, it can be open (anybody can attach) or encrypted (with different encryption strength like WEP, WPA, WPA2) or even authenticated (username:password). Example: WPA2-PSK-CCMP

MAC address: A media access control address (MAC address), also called physical address, is a unique identifier assigned to network interfaces for communications on the physical network segment. Example: 00:00:00:00:00:01

BSSID: MAC address of the access point. This is also an unique identifier. There can be several APs on the same network (same SSID) with different BSSIDs. Example: 00:00:00:00:00:02

IP address: An Internet Protocol address (IP address) is a numerical label assigned to each device (e.g., computer, mobile phones) participating in a computer network that uses the Internet Protocol for communication. Example:

Frequency: All wifi networks operate on a special frequency. The most common is the 2.4 GHz (2412-2484 MHz), or the 5 GHz (4980-5825 MHz).

Channel: Each frequency range is sub-divided into channels with a center frequency and bandwidth, analogous to the way radio and TV broadcast bands are sub-divided. For example: 2412 MHz = channel 1. 2437 MHz = channel 6.

Overlapping channel: the networks operate on close channels can cause interference on each other network. This can cause slow wifi data rate. In the 2.4 GHz band, 1, 6 and 11 are the only non-overlapping channels.

Guest network: Sharing your wifi with “guests”. The AP has dual SSIDs, dual security and the guest network is isolated from other networks.

Possible guest network: in WiFi Network Analyzer app, this message shows that it found a network that seems to be a guest network of the connected network.

WDS (expanded) network: WDS allows a wireless network to be expanded using multiple access points without the traditional requirement for a wired backbone to link them. Using WDS you can extend the range of your wireless network.

Possible WDS (expanded) network:  In WiFi Network Analyzer app, this message shows that it found a network that seems to be an expanded network of the connected network.

Link speed: This is the theoretical data rate. The current value of link speed depends on the distance from the AP, the signal strength, supported protocols by the AP and your mobile. In a wireless network, the link speed is always higher than the real achievable speed. Example: 433 Mpbs.

AP latency: 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.

Signal strength: This is the power of the received signal. The weakest the worst. A good signal is always higher than -75 dBm. If -90 dBm or lower, this is really bad. Example: -52 dBm.

Device-to-AP RTT support: Round trip time (RTT) between the AP and the mobile device over the WLAN is supported or not.

Wi-Fi Direct support: Wi-Fi Direct allows two devices to establish a direct, peer-to-peer Wi-Fi connection without requiring a wireless router

DFS: Dynamic Frequency Selection. The access points automatically select frequency channels with low interference levels.

No DFS: In WiFi Network Analyzer app, hide the networks that use DFS. The reason: they are using a lot of channels, and it’s not practical to show them by default because the screen will be congested and ugly. You can enable it using this check box.

Useful links:
How to optimize your wifi with Android
WiFi Speed Test guide



How Android WiFi booster apps work

When a mobile has slow wifi connection, most of people try to download some wifi booster application from Google Play.

But do they work? Do they really fix the wifi connection or this is just a lie? Checking the comments, you can be confused because there are people who reported good results and others who had negative experience.

But what is the truth? I tried to collect the reasons and the explanations.

What wifi booster apps can do

Usually, they do only two things:

  1. disconnect than reconnect to the wifi network.
    However it seems to be a stupid thing, it can work but only in two cases:

    • if the router can dynamically change channel and the channels are overcrowded (there are too many overlapping networks). In that case the router may change the used channel to a less overlapping one when the mobile reconnects. It can only work if the router supports this mode and it is enabled!
    • The other case, when there are other routers in the same network (usually it happens in enterprise environment, very rare in home network). In that case, if there is another router with better signal, the mobile will reconnect to this router instead of the previous one.
  2.  tell the system to use wifi in high perf mode.
    It works only from Android 3.1 (HONEYCOMB_MR1) and only if the device (the hardware) also supports it. Some devices have several power saving modes, if a program uses this high perf mode, the system tries to prevent the device to go power saving mode. It can increase the performance.
    But you have to know that this is not a special thing and not only used by booster applications. Usually, high perf mode is used by any applications that need good wifi performance. For example if you are using an application that downloads something from the Internet or use Voice over IP (voice chat), it uses this mode (mostly). And because most applications use this mode, using booster app will not have any additional effect as high perf mode has been already set.

And here is what the booster apps cannot do:

  • Increasing the maximum send signal power. This is not possible because it is limited in the most countries by laws thus the manufacturers also limit it and do not allow to set higher value. And because there is no official android API to access the deep level settings of the network card even if the hardware supports some.
  • Increasing the receive signal power. This is also not possible because it would need stronger/bigger antenna and of course a program cannot change the physical parameters of a device. Don’t forget, this is a two-way communication, even if the router can receive the signal of the mobile, the mobile also needs to receive the signal of the router and vice versa. The smaller antenna of the mobiles have worse performance and it cannot be changed by a program.

To summarize the above states, the booster applications can work in special cases but not really often.
High perf mode is used by normal applications too (and this is the preferred way because they will use this mode only when they need it, to save your battery, instead of to use it always and discharge your battery very fast).

About the reconnecting, you can even do it manually (turn off/on wifi) and can work only in the mentioned special cases. Instead you should use some analyzer application to detect network bottlenecks. They can help you to detect overlapping networks and find the best channel. Also they can warn you for other problems too.

So I think the effect of the wifi booster apps mostly based only on the belief. They don’t really have possibility to fix a bad wifi connection.

How to optimize your WiFi Network with Android

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

Signal strength

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.

Link speed

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.

AP latency

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).


Easy to verify your network

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

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”.


Detected overlapping network

WiFi Network Analyzer for Android

Sometimes, you would like to check your WiFi network if it works properly or detect if there are any problems. Taking into consideration the increasing number of the mobile devices (especially in case of the tablets), the well functioning WiFi network is a very important thing.

So if you want to verify your network, you can use my Wifi Network Analyzer application. Of course there are a lot of WiFi analyzer apps on the Android Market, but there is a big difference compared to my application:

They just display some static information and if you are  an average person and not an IT expert, it’s hard to understand what -79 dBm means for a signal length or it is good or not if the channel of your WiFi network is 11.

So I’ve decided that my application will be smart and process these information automatically then displays it in an easy form where you can see if your network works fine or not, even if you are just a beginner.
Here you can see the result if you click on the Analyze button:









Now you can detect the possible problems without understanding the exact meaning of the numbers.

If you are an expert, my WiFi Network Analyzer also can be a good choice.

It displays the usual static information like BSSID, frequency, channel, IP address, vendor, DNS and a lot of more but what is more important:
It measures the latency of the access point and tests the DNS resolving continuously.
Also there is a very useful dashboard, where you can check the most important details.

Finally, if you want to test the speed of your network, you can use my WiFi Speed Test application available on the Android Market.