What is WAN emulation?
Wide Area Networks (WANs) span regions, countries, and the world and typically involve distances of thousands of miles. WANs can include the web, the Internet, a cloud network, and many other topologies and configurations. For example, data communication over a satellite is an example of a WAN network.
A WAN Emulator or WAN emulation allows one to study the effects on an application or device in the lab, so that the full range of wide area network conditions and anomalies can be evaluated in terms of the effects on a device or application. For example, a direct broadcast satellite service provider could use a WAN emulator to determine why the users in a particular city experience poor picture quality (mpeg break up and pixelation) at certain times of the day.
Live WAN Is Too Costly To Test!
Software developers need to understand the performance characteristics of their app or device under both routine and adverse wide area network conditions. Developers must verify that the device or app will continue to perform when the WAN degrades. The reputation of the developer and the company is on the line and mistakes can be very costly. It is far easier to test an app or device with an emulated WAN compared to launching the product on a live WAN. The cost of a satellite, for example, is roughly $500,000 and the cost to launch the satellite, another $500,000. A WAN simulator is a very small fraction of this cost.
Why Should A Developer Test The App Under Real-World Condition?
Those who invent and implement apps and devices that will operate over a WAN, must be mindful of the range of conditions. Major considerations include packet delays, bandwidth limitations, and out of order packets. Signal propagation time increases over large distances. The range of conditions is discussed in our white paper Causes and Correlation of Network Impairments.
How can InterWorking Labs help with WAN simulation?
The Maxwell family of network emulators provide all-in-one solutions to WAN simulation:
Maxwell Pro offers pre-defined network scenarios so that you can simply click on the type of WAN emulation you wish to utilize. These include: Low Earth polar orbit satellite, geostationary orbit satellite. These emulations can be customized to make the latency or loss probability vary with time to account for the satellite's motion on the communication link. In addition, Maxwell Pro supports the ITU network model for evaluating multimedia transmission performance over a wide range of links. This includes the likelihood of occurrence of different types of network anomalies. Examples include the branch office user on a slow link, or users on different continents using transatlantic links.
The lower priced members of the Maxwell family, Mini Maxwell and Maxwell G emulate WANs by having the user enter the characteristics of the WAN to be emulated. This would include factors such as estimated delay, packet loss, and re-ordering. Consultation with InterWorking Labs application engineers may be required to optimize the emulated WAN.