Defying Wireless Conventions
Meet Nick, Director of Advanced Development at Sonos, and learn how his team designed SonosNet, the wireless mesh network behind the Sonos Multi-Room Music System.
What drove your decisions around wireless?
Nick: We had three key goals for implementing our wireless solution: extensive coverage, easy setup and reliability. Because the Sonos Multi-Room Music System is designed to play music all over your house, we needed our wireless network to work all over the house—in every room, near or far. Also, we were creating a consumer electronics product, not a network device, so setting it up needed to be out-of-the-box simple. Unlike most other wireless networks, Sonos automatically generates encryption keys and SSIDs so you don’t have to. And lastly, we knew that we would only be successful if playing music across the wireless network was as reliable as your analogue stereo.
Why did you choose a wireless mesh network over the more conventional access point model?
Nick: A traditional access point system with a central hub relaying all the traffic didn’t give us the range of coverage we needed for an entire home, or the performance. When you’re dealing with synchronised digital music playback, you don't want to worry about dead spots or low signal strength. As long as each ZonePlayer is in range of one of the others, SonosNet can figure out how to get the music from the Internet and your computer to the rooms where you want to enjoy it. And Controllers are handed off transparently from one ZonePlayer to the next, so you can control the whole system from anywhere. As far as I know, no other home entertainment product uses a wireless mesh network in this way.
What specific software features did you incorporate into SonosNet?
Nick: There are three things I’m most proud of. Our setup technology searches for the wireless channel with the least interference rather than just picking the standard—and sets up a wireless network that is secure by default. We designed a mesh networking stack to automatically optimise the path the data travels on within a house, so you hear the music without interruption. And we incorporated multi-casting support, so we can deliver the same data, or in this case, the same song, to multiple rooms efficiently.
What about hardware features?
Nick: First of all, Sonos starts with the latest wireless networking hardware in all its ZonePlayers. That’s the same sophisticated radio technology used in today's latest enterprise wireless access points. But there's more to it than that. For instance, when we designed the antennas for the Controller, we accounted for where your hands would be when holding it and selecting the music, and made sure the antennas would operate at maximum efficiency under these real world conditions. And each ZonePlayer is individually tested on all three antennas during manufacturing to verify it can send and receive with the expected signal strength. This all translates into the best possible wireless range and performance.