I was approached a couple of days ago by one of our large customers, a major food manufacturer, to help them design a testing cycle for an hand-held device, to scan barcodes on their product’s pallets, as they are being unloaded from supply trucks into their regional depots. The devices utilize a LAN based wireless infrastructure, but can also switch to a 3G carrier based network, for backup and if they step outside the normal coverage of the WLAN infrastructure. Each device is fitted with a 3G mini card, similar in nature to the ones we all carry on our laptops. The custom made application is very lead, and send only about 200kbps of traffic. The 3G bandwidth is asynchronous in nature, 1370kbps download, and 512 kbps upload.
Given the application traffic requirements, the challenge is not going to be the amount of traffic (Throughput) , but rather the network conditions, or impairments, that are affecting how the application traffic is going to be transmitted over the network, eventually arriving at the corporate data center south of the nation’s capital.
Using VE Catcher 4.6, a model of the latency and packet loss characteristics was created, for a period of 10 days. Two separate devices where utilized, on one AT&T 3G network, the other, on the Sprint network, to ensure carrier availability (the project call for a 50% split among the networks). A pilot site, south of the data center, was selected, and VE Catcher created two parallel recordings, one for device “A” and another for device in the alternative carrier.
Once the behavioral model has been created, Shunra’s Virtual Enterprise appliance will allow creating a “test-bed” where the application will be sending real traffic to the data center over an emulated link. The network conditions will be imported from VE Catcher and reflect the exact conditions observed at each of the 3G carriers.
The performance of the application, running over the emulated links will allow the testing team to predict the behavior of the application well before field deployment is completed, and make adjustments required by the application and also predict behavior under extreme conditions, like heavy network traffic, inclement weather or other events.
You may not always use WAN emulation, but when you do, use Shunra.
Shunra Virtual Enterprise is your guaranty to a successful deployment.
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