Light weight service discovery protocol

Abstract

A service discovery protocol is provided for use in personal area networks and other ad-hoc networking environments. The service discovery protocol is specifically designed to take into account the dynamic network configurations, bandwidth constraints as well as other characteristics of these types of networks. One of the key differentiators of the service discovery protocol is that it relies on a dynamically selected service directory device to manage the amount of information being distributed in the network.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an exemplary personal area network;

FIG. 2 illustrates an exemplary messaging scheme for network discovery in accordance with the present invention;

FIG. 3 illustrates an exemplary messaging scheme for service discovery in accordance with one embodiment of the present invention; and

FIG. 4 illustrates an exemplary messaging scheme for service discovery in accordance with another embodiment of the present invention.

Claims

1. A service discovery protocol for a network, comprising: selecting a service directory device from amongst a plurality of network devices that form a network;advertising available services to the service directory device by network devices that form the network;maintaining the available services at the service directory device; andresponding to queries regarding the available services from other network devices in the network.

2. The service discovery protocol of claim 1 wherein selecting a service directory device further comprises assigning a priority to each network device which may join an ad-hoc network during device configuration; and selecting the service directory device from amongst a plurality of network devices that form the network based in part on the priority assigned to network devices.

3. The service discovery protocol of claim 1 further comprises communicating an identifier for the network by the service directory device to network devices that form the network.

4. The service discovery protocol of claim 3 wherein the identifier is further defined as a multicast address for the network devices that form the network.

5. The service discovery protocol of claim 1 further comprises communicating a service description format by the service directory device to the network devices that form the network.

6. The service discovery protocol of claim 5 wherein advertising available services to the service directory device further comprises using the service description format provided by the service directory device.

7. The service discovery protocol of claim 1 wherein advertising available service to the service directory device further comprises sending a unicast message to the service directory device.

8. The service discovery protocol of claim 1 further comprises requesting service discovery by sending a unicast message to the service directory device.

9. The service discovery protocol of claim 1 further comprises selecting a different service directory device from amongst the plurality of network devices that form the network when the service directory device departs the network.

10. The service discovery protocol of claim 1 further comprises communicating a shared security key by the service directory device to the network devices that form the network.

11. The service discovery protocol of claim 1 further comprises selecting a service directory device for a different ad-hoc network from amongst a plurality of network devices, wherein at least one of the network devices resides in each of the networks.

12. The service discovery protocol of claim 11 wherein the same network device serves as the service directory device in each of the networks.

13. A service discovery protocol for a network, comprising: assigning a priority to each network device which may join a network;selecting a service directory device from amongst a plurality of network devices that form the network based in part on the priority assigned to network devices;maintaining network address information at the service directory device for each of the network devices that form the network, thereby enabling service discovery by the network devices.

14. The service discovery protocol of claim 13 further comprises selecting a different service directory device from amongst the plurality of network devices that form the network when the service directory device departs the network.

15. The service discovery protocol of claim 13 wherein selecting a service directory device further comprises selecting a network device having the highest priority as the service directory device.

16. The service discovery protocol of claim 15 wherein selecting a service directory device further comprises selecting a network device having the highest numerical network address when at least two network devices have the same highest priority.

17. The service discovery protocol of claim 13 further comprises advertising the priority of a given network device upon the given network device joining the network and assessing the selection of the service directory device in view of the priority of the given network device.

18. The service discovery protocol of claim 17 wherein the assessment of the service directory device selection is performed by the service directory device in accordance with a predefined rule set, whereby excessive reassignment of the service directory device may be avoided.

19. The service discovery protocol of claim 13 further comprises receiving network address information for a given network device from the service directory device and requesting service discovery from the given network device using the network address information.

20. The service discovery protocol of claim 13 further comprises broadcasting a discovery messages from a given network device to inquiry as to the existence of the network.

21. The service discovery protocol of claim 20 wherein the discovery message includes a public key for the given network device.

22. The service discovery protocol of claim 20 further comprises responding to the discovery message by communicating a shared security key from the service directory device to the given network device.

23. A service discovery protocol for a network, comprising: introducing a controlling network device into a potential ad-hoc network location;broadcasting a service query message from the controlling network device to any other network devices residing in the potential ad-hoc network location, where the service query message includes an identifier for a network; andadvertising available services from at least one other network device to the controlling network device in response to the service query message, thereby forming the network.

24. The service discovery protocol of claim 23 wherein the identifier is further defined as a multicast address for the network devices that form the network.

25. The service discovery protocol of claim 23 further comprises communicating a service description format by the controlling network device to the other network devices that form the network.

26. The service discovery protocol of claim 25 wherein advertising available services to the service directory device further comprises using the service description format provided by the controlling network device.