In order to demonstrate use the of UDP as transport on Nordic's IPv6 stack, a server that responds to a client message is defined. The data formats and message exchange is described in Figure 1 below.

Figure 1: UDP data exchange.

As UDP is used as transport and has no tight coupling with BLE, the server and clients could be PC-based applications talking to the kits running a complementary role. The only prerequisite for this is that the UDP client knows the server's IPv6 address. This concept of communication between PC application to nRF51 example on the kit, or nRF51 to nRF51 is emphasized in Figure 2 below.

Figure 2: Setup of Nordic's IPv6 stack based UDP examples.

Note: The UDP transmissions are triggered by a timer and the reception is asynchronous.

Client

Server