Dual-Mesh
In a typical mesh network, devices have links with multiple other devices rather than a single router or hub. The more these links overlap, the stronger the mesh. With Insteon, this mesh is created in two ways.
Physically, dual-band Insteon devices communicate over both a 915MHz wireless radio and a 131KHz powerline network. Dual-band devices can transmit out over both mediums and can also bridge mediums for single-band devices. Battery-powered devices are wireless-only and some legacy wall-powered devices are powerline only. Combined with a network of primarily dual-band devices, these single-band devices still contribute to the mesh, just in their respective medium only.
Logically, every Insteon device is interconnected to every other Insteon device. Wall-powered devices can transmit and receive. Battery-powered devices are typically asleep except when activated for their function. These battery powered devices do not contribute to the mesh when asleep.
Simulcast
Sending messages in the Insteon world is unlike any other networking technology. Rather than point-to-point messages, Insteon uses a cascading broadcast and repeat system.
You're at a baseball game and decide you want peanuts. You could shout over the entire crowd and hope your voice is heard or you could use the crowd to your advantage. If you could get the entire crowd to chant with you, "peanuts, peanuts, peanuts," your voice would be heard loud and clear in the harmonious chorus of thousands of patrons.
In the world of Insteon, your devices are your home's chorus and work together to rebroadcast messages simultaneously. For a given device, the initial message will only reach so many devices in the home. Every device that has heard this message will then rebroadcast it three additional times in sync with the entire network. The result is four opportunities to hear a message with every device in your home shouting the message, simultaneously.
Statelink
Simulcasting only works when each device in the chain knows what to do. While it's one thing for a single device to control another, it's another thing entirely for a single device to control an entire home. Typically, the transmission would tell a device specifically what is needed, "Chandelier to 50%." With Statelink, the desired action is already stored in the devices' internal memory.
When a device broadcasts "Scene 5," every device who has a role in that scene