How to get link speed programmatically?

Question

I am working on an app and it is almost finished except only one thing: I don't know how to get link speed and place it in the status bar.I am new to Java so if somebody could help me I would be very grateful. P.S. Sorry for bad English.

Answer 1

As the repliers suggest, your question is not very clear. You could be referring to the link connection speed (i.e up to 54 Mbps with good signal reception Wifi or up to 7.2 Mbps with full speed HSDPA) which depends on:

• The network interface you are using at a time. Some phones allow tethering which means you can have both Wifi and Mobile Data Link (GPRS/3G/HSDPA) active at the same time, or on automatic switch (if your Wifi connection drops your phone will switch to Mobile network automatically if activated).
• The connection speed negotiated at a time. Depending on signal quality/carrier network configuration (some have max. speed limited)/mobile data contract (monthly bandwith quota exceeded normally means defaulting to GPRS speed).

In this case I am afraid there is no standard Java API methods to know it, but the Android API the needed functionality:

• For WiFi link speed check WifiInfo.getLinkSpeed()
• For Mobile Data Link I am afraid that you can only check TelefonyManager.getNetworkType() to determine the current Mobile Data Link type. You should then aproximate to actual speed by link type (i.e. for GPRS up to 128 kbps, for EDGE up to 236.8 kpbs, for 3G up to 2 Mbps, for HSDPA up to 7.2 Mbps). Take into consideration that this is only an aproximation. Your could be conneting using HSDPA but your carrier limiting the top speed to 2 Mbps.

In the other case that you refer the current (Download/Upload) data link speed this is only available at a high level, actually measuring not the link speed but the speed between your phone and a server, which can be determinted not only by your link speed but also by many other factors (all the links between your phone an server, the server itself, etc.). You could just measure "HTTP level speed" which means HTTP data speed (leaving out overhead traffic for data packets), since normally only HTTP connections are supported in every scenario (your carrier could be hiding you behind a proxy that filters everything out but HTTP traffic).

If you are using 8 level API an interesting feature called TrafficStats is also available. This lets you know the sent/received packets at a low level exchanged by your phone over the Mobile Data Link, which may offer just the information you where looking for (use these measurements with elapsed times and you can easily measure current/average used data link speed).

Answer 2

You cannot tell directly. You must ask the underlying operating system. For OS X you can parse the output from "/sbin/ifconfig" on the appropriate network port.

Answer 3

You can also write extension using JNI, and ask connection speed using C. It's just in case if you don't want to parse output from other application, but please keep in mind that this solution isn't portable.