Conveying state changes using connectionless messaging and a store-and-forward cache

An advertising device comprising:

• at least one producer app that generates service-related messages;
• a first transceiver configured to communicate via a wireless air interface;
• a second transceiver configured to communicate via the wireless air interface;
• a discovery service component configured to broadcast low-level advertisements via the first transceiver;
• a local cache to store the service-related messages;
• a message manager to:
• store the service-related messages in the local cache;
• increment, each time a message is added to the local cache, a value of an internal state variable stored on the advertising device to associate each value of the internal state variable with a corresponding one of the plurality of messages;
• prompt the discovery service to broadcast, in response to a new message being added to the local cache, a low-level advertisement via the first transceiver, wherein the low-level advertisement includes an identifier of the advertising device and a new value of the internal state variable associated with the new message;
• receive, from a discovering device, a request for the new message in the local cache associated with the new value of the internal state variable;
• and
• unicast, via the second transceiver, in response to the request, the new message to the discovering device.

A non-transitory, tangible processor readable storage medium, encoded with processor readable instructions to perform a method for sending messages from an advertising device to a discovering device, the method comprising:

• storing, at the advertising device, a plurality of messages in a local cache;
• incrementing, each time a message is added to the local cache, a value of an internal state variable stored on the advertising device to associate each value of the internal state variable with a corresponding one of the plurality of messages;
• broadcasting, in response to a new message being added to the local cache, a low-level advertisement, wherein the low-level advertisement includes an identifier of the advertising device and a new value of the internal state variable associated with the new message;
• receiving, from a discovering device, a request for the new message in the local cache associated with the new value of the internal state variable;
• and
• unicasting in response to the request, the new message to the discovering device.