Showing posts with label network. Show all posts
Showing posts with label network. Show all posts

Tuesday, July 13, 2010

DummyNet - HowTo { an open-source tool to tweak network latency and bandwidth }

Any service allowing to  tweak Network Latency and Bandwidth as per desire
for testing application  performance at different network latency scenarios.

Tools/Technology Used:
DummyNet
{Home}URL: http://info.iet.unipi.it/~luigi/dummynet/

Background:
Normally the difference which comes in  development and  deployment
environment of Web Applications, is of bandwidth and latency.
To test the applications in actual scenario, one needs to tweak the latency as
per deployment scene and then use it.
There are few paid VE Technology based services like "Shunra" for this. But
we required a free, open-source application, if possible for windows.
DummyNet, it's an old Italian university project started for BSD systems,
recently ported for Windows also. It helps in reducing latency of NIC to
desired level.

Execution Method:
[] Install NDIS Driver
1.  Open the configuration panel for the network card in use
  {right click on the icon on the SYSTRAY, or go to 'Control
Panel' > 'Network' to select}
2.  Click on 'Properties' > 'Install' > 'Service' > 'Add'
3.  Click on 'Driver Disk' and select 'netipfw.inf' in the
folder it has been extracted to.
4.  Select 'ipfw+dummynet' which should be the only service
visible.
5.  Click 'Accept' on the warnings for the installation of an
unknown driver.

Create a BAT-File for your Application to be run under test bandwidth &
latency with following content
--------------------------------------File Content Starts  from Next line
@echo off
@set CYGWIN=nodosfilewarning
@ipfw -q flush
@ipfw -q pipe flush
@echo #################
@echo ## Setting up ##
@echo #################
ipfw pipe 3 config delay 1000ms bw 500Kbit/s mask all
ipfw add pipe 3 ip from any to any
ipfw pipe show

@echo ""
@echo "Network Tweaking Done, Start Testing."
@echo ""
@echo "Press Enter when testing is done, to restore original Network Settings."
pause

@echo #################
@echo ## Cleaning up ##
@echo #################
ipfw -q flush
ipfw -q pipe flush
pause
--------------------------------------File Content Ends at Previous line
Here, 1000ms is latency set and can be changed to desired value
500 Kbps is bandwidth set and can be changed to desired value
'delay x' and 'bw x'; both can be used separately also as per need
either place a command running your application to be tested in place of
'your_command_running_your_app'; or simple remove that line 
and when the command gets paused at the first pause, run your appl ication
manually.
 

Installation:
Follow the wlak-through video on Youtube at :
http://www.youtube.com/watch?v=jP-DrxTMXDc

Then, to test if it gets installed properly as a network services. It has a testme.bat file showing different tests, just run it and
check statistics.

I tested it on Windows XP, Vista, 7... and it worked great.

Wednesday, June 23, 2010

Microsoft Network Monitor {its free, it's efficient}

Microsoft Network Monitor

Brief Description:
One of the best network analysis utilities on Windows. 
You can choose any Physical/Virtual NIC present on your machine to capture traffic.
It shows the traffic in a nested tree menu ordered by Application Name generating that traffic.
This way you can analyse entire network traffic per application from your machine.
Tool to allow capturing and protocol analysis of network traffic.
It's free, it's fine network packets analysis utility.

It also allows you to save captured data into PCAP files, and can even open and analyze PCAP files.

Download Link & Installation:

How To Capture Network Traffic:

msnm.jpg