Being a networking related product developer, we always face issues which can not be easily reproducted in LAB(because in most cases we have LAN only environments).
Here I introduce you a tool, WANem – a WAN emulator tool from TATA. And we can benifit a lot in reproducing issues or trouble shooting simply by using WANem.
What does WANem do?
WANem is a Wide Area Network Emulator, meant to provide a real experience of a Wide Area Network/Internet, during application development / testing over a LAN environment. Typically application developers develop applications on a LAN while the intended purpose for the same could be, clients accessing the same over the WAN or even the Internet. WANem thus allows the application development team to setup a transparent application gateway which can be used to simulate WAN characteristics like Network delay, Packet loss, Packet corruption, Disconnections, Packet re-ordering, Jitter, etc. WANem can be used to simulate Wide Area Network conditions for Data/Voice traffic and is released under the widely acceptable GPL v2 license. WANem thus provides emulation of Wide Area Network characteristics and thus allows data/voice applications to be tested in a realistic WAN environment before they are moved into production at an affordable cost. WANem is built on top of other FLOSS [Free Libre and OpenSource] components and like other intelligent FLOSS projects has chosen not to re-invent the wheel as much as possible.
Where to download WANem?
WANem is an open-source project, and it hosts on source forge, you can download it here: http://wanem.sourceforge.net
Start to use.
1. Start WANem image with VMware
2. Choose your network configuration, DHCP or manual static IP. Here I’m using static IP.
3. Setup your password for your VM(Knoppix).
4. Open a browser and navigate to WANem with an URL like this: http://ip-address/WANem, such as http://172.16.184.203/WANem
5. Add route rule for your test endpoints/peers
6. Start WANem by a specified Loss percentage.
7. Run your tests.
A sample route setting
a. Delete default route for your endpoint
route delete 0.0.0.0
b. Add a force route to WANem
route add 0.0.0.0 mask 0.0.0.0 172.16.184.203
* You need to change the IP address with the IP address of your own WANem server.
However, all the data from this endpoint will be forced to route to WANem if this route is applied. If you wish it works only for one another peer IP, you can change the command to
route add 172.16.184.202 mask 255.255.255.255 172.16.184.203
This means, if you are connecting or sending data to 172.16.184.202 from this endpoint, all the data packages will first route to 172.16.184.203 (WANem server)
c. Test your route
You can use this command to test the route setting if your application is working under windows:
tracert 172.16.184.202
If you have any questions about using WANem, you can leave a message for me under this post.