Interoperability and Conformance Testing: What’s the Difference?

Hello! I’m Cornelis Plomp, a test technician at the UNH InterOperability Laboratory. I am currently a junior in mechanical engineering at UNH. At the IOL, I do a lot of the actual testing on devices, and I also help write some of our test plans. I have been working at the lab for two years in the Baseband testing group. In this group I work with devices such as switches and test a variety of test plans specifically for IEEE 802.3 standard compliance. Here at the lab,  interoperability and conformance are both big parts of our testing. We offer a wide range of services to our members that include conformance and interoperability and a question we’re asked a lot is “What’s the difference?”. In this post, I’ll be giving a brief overview of both types  of testing and clearing up any confusion.

The main focus of interoperability testing is making sure the device that is being tested is able to work in sync with a wide range of other devices. This testing usually involves having the device operate with our testbed of link partners, sending traffic back and forth with other devices that it might encounter in the wild. The goal of this testing is to ensure that if an end user puts together any two devices that are supposed to be compatible, those devices will work together. As an example, you might buy a new router for your house. If that router is compatible with the network card in your PC, you’ll be able to get internet to your computer with no problems. If they aren’t compatible, you’re going to have a long day trying to make them communicate.

In contrast, conformance testing is focused on ensuring that the device being tested is compliant with a given set of standards. As an example, we might have a company that wants to be able to say their device has a Media Access Control (MAC) layer that is compliant to the IEEE 802.3 standard, which is a standard that sets out the requirements for Ethernet physical and MAC layers. If the device passes our testing, they can say with confidence that their device conforms to the standard. This is helpful for companies because it provides confidence that their device is doing the right thing according to the standards body (generally experts in the field) and greatly reduces the chance of unexpected problems caused by that layer popping up later down the road.

To summarize, an interoperability test ensures that a device will work with other devices, while a conformance test ensures that a device will meet the requirements set out by some standards body like the IEEE. Both types of testing are important for a well-functioning device, and at the UNH InterOperability Laboratory we’re happy to perform either one!