Last updated 6 February 2008

This is a skeleton draft article about Netlimiter2 Monitor.  This freeware application is very useful if you want to determine what applications or services are undertaking network and internet traffic, the volume of traffic and roughly when the traffic took place.  There is a payware application Netlimiter2 Pro that has lots of other functionality but for the average punter the freeware version has functionality that is well worth looking at.  I've referred to the freeware version below as simply NL2

I became interested in NL2 after a friend expressed concern about frequent repetitive small parcels of internet traffic that his PC was evidencing through NetMeter.  He was unable to determine what internal or external application or service was undertaking that traffic.  I run NetMeter and its display widow is visible on my desktop all the time.   That gives a visual indication of total inwards and outwards network traffic that is taking place and the speed of the traffic. 

NetMeter is freeware and is available from here:

http://www.softpedia.com/get/Network-Tools/Bandwidth-Tools/NetMeter.shtml

I have Netmeter configured so that it it loads automatically at startup.  It shows no display until there is some internet traffic.  It then pops up a small graphical display whenever it detects inwards or outwards internet traffic.  When the traffic ceases, the display then disappears.  It can be configured to generate a log showing totals for traffic. 

Here are some clips showing what the Netmeter panel looks like:

• downloading large file from Microsoft site
  
• uploading images to Google site

Netmeter can be useful in alerting you about internet traffic that you know nothing about.  However, it does not indicate what applications or services are responsible for the traffic.  So you need some other application that you can use to determine what applications or services are responsible for the traffic and then, if appropriate, take steps to prevent inappropriate traffic.

The application that I have been using in the past to find out what is undertaking internet traffic that is evidenced by Netmeter or other means is TCPview.  This is an excellent freeware application created by Mark Russinovitch and is available from here: 

http://www.microsoft.com/technet/sysinternals/Utilities/TcpView.mspx

However, the detail provided by TCPview and its method of presentation can be a bit intimidating for the average punter.  Terry Bibo suggested NL2 as an alternative.  (Lots of good articles are on Terry's site here: http://www.users.on.net/~tbibo/  )  After trying it I think that its functionality and method of presentation of details about internet traffic would be preferred by many folk, who would find it easier to use and to comprehend than TCPview.  It also provides summary statistics and time-related statistics that are very useful.  It is available from here:

http://www.netlimiter.com/download.php

I have included a few sample pics in this article showing what the NL2 displays look like:

• Display of executables' names.  The names of executables that are running and that have internet connectivity enabled is shown.  However the only executable that is actively engaged in trafficking at the time of the snapshot is picasa2.exe  This traffic related to me creating a web album at Google. 
  
  
• Display of executables' descriptions.  This is the same type of display but shows descriptions of executables rather than the executables' names. You can switch between names and descriptions through View / Options / Cnn Tree.  (Alternatively, you could also display the executable's path and name by that means.)
  
  
• Another pic with executable description.   This time Outlook Express activity is indicated.
  
  
• Display of summary statistics.  This is a summary showing information for traffic relating to Outlook Express (msimn.exe) for today till this time.  Traffic volumes are shown in one hour lots so it's possible to get a fix on when the traffic occurred (who the heck was on the internet at that time???).   It's also possible to get a summary for yesterday, this month, last month, this year.   The summary statistics display is shown by clicking on the graphical bars icon beside the N and ? icons towards the top of the main display.   Alternatively, right-click an executable, then select Show statistics.

I have not attempted to explain all the ins and outs of NL2 in this article.  For instance, it can be used to monitor traffic on your network as well as internet traffic.  Give it a try - it's worth having if you have a need to learn about what's undertaking internet and/or network activity on your system.

You might be interested in some of the other articles on my site: www.pcug.org.au/boesen/index.htm

Mike Boesen