User priority based preemption techniques in a time division multiple access multi-hop ad hoc network

In a multi-hop TDMA network comprising a source node seeking to transmit a first communication stream having QoS requirements to a destination node, a method for allowing an intermediate node to preempt a lower priority communication stream for use by the source node, the method comprising:

• transmitting, from the source node, a scout request message to initiate a slot allocation procedure for the first communication stream;
• receiving, at an intermediate node along a route between the source node and a destination node, the scout request message;
• determining, at the intermediate node, whether free time slots are available to support the first communication stream of the source node;
• when the intermediate node determines that free time slots are not available to support the first communication stream of the source node, determining, at the intermediate node, whether the intermediate node is supporting one or more communication streams through the intermediate node.

In a multi-hop TDMA network comprising a source node seeking to transmit a first communication stream to a destination node, a method for allowing the source node to preempt a lower priority communication stream, the method comprising:

• supporting user priorities during slot scheduling in the multi-hop TDMA network based on stream-identifiers (IDs) and stream priority values exchanged by each of the nodes in the multi-hop TDMA network;
• transmitting, a scout request message to next-hop node along a route towards the destination node, wherein the scout request message comprises a stream ID and a user priority value of the node that initiated time slot scheduling procedure;
• determining, if free time slots are available along the route between the source node and the destination node to meet QoS requirements of the first communication stream;
• when free time slots are not available at a node along the route towards the destination node, determining, based on the stream priorities in SAT and neighbor tables, whether there is a lower priority communication stream in the neighborhood which is using one or more time slots;
• when there is a lower priority communication stream, freeing the particular time slots currently being used by the lower priority communication stream;
• and
• allocating the particular time slots for the first communication stream originated by the source node.