Geocast protocol for wireless sensor network
A protocol for providing location-based communication services in wireless sensor networks utilizes dynamic selection of forwarding devices, dynamic forwarding decisions, and intelligent backoff. Dynamic selection of forwarding devices limits the number of transmissions by dynamically selecting the devices that forward a message. Dynamic forwarding decisions implement different heuristics for different devices. According to intelligent backoff, devices that are closer to a destination region backoff for a shorter period of time than those which are further away from the destination region.
1. A device comprising:
a processor; and
memory coupled to the processor, the memory comprising executable instructions that when executed by the processor cause the processor to effectuate operations comprising:
receiving a geocast packet;
determining a first location of the device;
analyzing the received geocast packet to determine a second location of a transmitting device that transmitted the geocast packet;
analyzing the received geocast packet to determine a third location of a destination region of the geocast packet;
determining a first distance between the second location and the third location;
determining a second distance between the first location and the third location;
determining whether the received geocast packet constitutes a negative hop based upon a comparison of the first distance and the second distance;
when it is determined that the second distance is greater than the first distance, determining that the received geocast packet constitutes a negative hop;
incrementing a negative hop value when the second distance is greater than the first distance;
determining whether or not the negative hop value is greater than a threshold value;
if the negative hop value is greater than the threshold value, retransmitting the received geocast packet; and
if the negative hop value is not greater than the threshold value, waiting a predetermined amount of time before retransmitting the received geocast packet,
wherein the predetermined time is based on the second distance.
2. The device of claim 1 , the operations further comprising: generating an updated geocast packet by updating the received geocast packet to comprise an indication of the incremented negative hop value.
3. The device of claim 1 , the operations further comprising:
determining a number of negative hops the received geocast packet has accrued;
when it is determined that the number of negative hops the received geocast packet has accrued is equal to zero, determining whether to retransmit the received geocast packet based on heuristics considered in the alternative; and
when it is determined that the number of negative hops the received geocast packet has accrued is not zero, determining whether to retransmit the received geocast packet based on a cumulative consideration of heuristics.
4. The device of claim 1 , the operations further comprising:
determining a number of negative hops the received geocast packet has accrued;
when it is determined that the number of negative hops the received geocast packet has accrued is equal to zero, determining to retransmit the received geocast packet when:
the device has received less than a threshold number of geocast packets having a globally unique geocast identifier; or
the device is closer to the third location than any other device from which the device has received a geocast packet having the globally unique geocast identifier.
5. A non-transitory computer-readable storage medium having stored thereon executable instructions that when executed by a processor, cause the processor to effectuation operations comprising:
receiving a geocast packet;
determining a first location of the processor;
analyzing the received geocast packet to determine a second location of a transmitting device that transmitted the geocast packet;
analyzing the received geocast packet to determine a third location of a destination region of the geocast packet;
determining a first distance between the second location and the third location;
determining a second distance between the first location and the third location;
determining whether the received geocast packet constitutes a negative hop based upon a comparison of the first distance and the second distance;
when it is determined that the second distance is greater than the first distance, determining that the received geocast packet constitutes a negative hop;
incrementing a negative hop value when the second distance is greater than the first distance;
determining whether or not the negative hop value is greater than a threshold value;
if the negative hop value is greater than the threshold value, retransmitting the received geocast packet; and
if the negative hop value is not greater than the threshold value, waiting a predetermined amount of time before retransmitting the received geocast packet,
wherein the predetermined time is based on the second distance.
6. The non-transitory computer-readable storage medium of claim 5 , the operations further comprising:
generating an updated geocast packet by updating the received geocast packet to comprise an indication of the incremented negative hop value.
7. The non-transitory computer-readable storage medium of claim 5 , the operations further comprising;
determining a number of negative hops the received geocast packet has accrued;
when it is determined that the number of negative hops the received geocast packet has accrued is equal to zero, determining whether to retransmit the received geocast packet based on heuristics considered in the alternative; and
when it is determined that the number of negative hops the received geocast packet has accrued is not zero, determining whether to retransmit the received geocast packet based on a cumulative consideration of heuristics.
8. The non-transitory computer-readable storage medium of claim 5 , the operations further comprising:
determining a number of negative hops the received geocast packet has accrued;
when it is determined that the number of negative hops the received geocast packet has accrued is equal to zero, determining to retransmit the received geocast packet when:
the device has received less than a threshold number of geocast packets having a globally unique geocast identifier; or
the device is closer to the third location than any other device from which the device has received a geocast packet having the globally unique geocast identifier.
9. A method comprising:
receiving, by a device, a geocast packet;
determining a first location of the device;
analyzing the received geocast packet to determine a second location of a transmitting device that transmitted the geocast packet;
analyzing the received geocast packet to determine a third location of a destination region of the geocast packet;
determining a first distance between the second location and the third location;
determining a second distance between the first location and the third location;
determining that the received geocast packet constitutes a negative hop when the second distance is greater than the first distance;
when it is determined that the second distance is greater than the first distance, determining that the received geocast packet constitutes a negative hop;
incrementing a negative hop value when the second distance is greater than the first distance;
determining whether or not the negative hop value is greater than a threshold value;
if the negative hop value is greater than the threshold value, retransmitting the received geocast packet; and
if the negative hop value is not greater than the threshold value, waiting a predetermined amount of time before retransmitting the received geocast packet,
wherein the predetermined time is based on the second distance.
10. The method of claim 9 , further comprising:
determining a number of negative hops the received geocast packet has accrued;
when it is determined that the number of negative hops the received geocast packet has accrued is equal to zero, determining whether to retransmit the received geocast packet based on heuristics considered in the alternative; and
when it is determined that the number of negative hops the received geocast packet has accrued is not zero, determining whether to retransmit the received geocast packet based on a cumulative consideration of heuristics.
11. The method of claim 9 , further comprising:
determining a number of negative hops the received geocast packet has accrued;
when it is determined that the number of negative hops the received geocast packet has accrued is equal to zero, determining to retransmit the received geocast packet when:
the device has received less than a threshold number of geocast packets having a globally unique geocast identifier; or
the device is closer to the third location than any other device from which the device has received a geocast packet having the globally unique geocast identifier.