BLE Mesh Overview(1)

    SIG announce the BLE mesh at 2017 July. Not only for BLE 5 but also compatible with BLE4.0 (or later). BLE mesh is implement by add new layers on the BLE physical layer so it need to make appropriate modification on the old BLE 4.0 firmware to get the mesh work.

    Bluetooth mesh follows Bluetooth technology’s architecture whereby GATT
“Profiles”.To avoid GATT Profiles being mistaken for the mesh equivalent, mesh profiles
are called “Models”

The Bluetooth mesh specification details four types
Relay Nodes :
       Relay Nodes re-transmit received packets and are the mechanism by which packets rapidly propagate across the entire network.The downside of relaying is increased current consumption because it relies on the nodes being continuously ‘awake’.

Low Power Nodes & Friend Nodes:
        Low Power Nodes work in tandem with “Friend Nodes”.Friend Nodes are typically
mains powered so can remain permanently awake; the devices cache any messages destined
for the LPN. The LPNs switch to receive’ mode according to a predetermined schedule, accept
cached messages, operate as instructed, and then rapidly return to a power-saving ‘sleep’ state.

Proxy Nodes:
       Proxy Nodes allow devices that run the Bluetooth low energy stack but don’t support Bluetooth
mesh (for example, the current generation of smartphones) to connect to a Bluetooth mesh network. Interaction is achieved via both the node and device’s Generic Attribute Profile (GATT) interface.






Ref:
      1. ULP Wireless Quarter 10-11
      2. nRF5 SDK for Mesh
      3. Bluetooth mesh networking SIG