Detection and handling of lost messages during load-balancing routing protocols
View Patent ↗Methods that enable the detection and handling of lost messages during load-balancing routing protocols are disclosed. In accordance with the illustrative embodiment, when a candidate intermediate node N receives a routing-protocol message, node N performs: (1) a first procedure that is capable of detecting some lost routing-protocol messages that were previously transmitted by node N, and (2) a second procedure that is capable of detecting some lost routing-protocol messages that were previously transmitted by a neighbor of node N.
1. A method comprising:
(a) receiving at a first node in a network a first message from a second node in said network, wherein said first message is for establishing a route in said network from a source node in said network to a destination node in said network, and wherein said first message comprises
(i) a route R from said source node to said second node, and
(ii) a value of a load metric at one or more nodes in said route R;
(b) determining the value W of said load metric at said first node;
(c) receiving at said first node from a third node in said network, after the receipt of said first message, a second message that is for establishing the route in said network from said source node to said destination node;
and
(d) inferring, after the receipt of said second message, that said second node did not receive a third message transmitted by said first node, when:
(i) said first message indicates a value Y for said load metric at said second node;
(ii) said first message indicates a value X for said load metric summed over the nodes in said route R;
(iii) said second message comprises a route S that starts from said source node and does not include said second node;
(iv) said second message indicates a value L for said load metric summed over the nodes in said route S; and
(v) L+W+Y<X.
2. The method of claim 1 wherein said first message and said second message are multicast messages.
3. The method of claim 1 wherein said network is a multi-hop ad-hoc wireless network.
4. The method of claim 3 wherein said second node is a single hop from said first node.
5. The method of claim 1 further comprising:
(e) transmitting from said first node a fourth message that is for establishing a route in said network from said source node to said destination node;
wherein said third message comprises:
(i) a route S that starts from said source node and does not include said second node, and
(ii) the value of said load metric at one or more nodes in said route S; and
wherein said fourth message comprises:
(i) a route S′ consisting of said route S plus said first node appended at the end, and
(ii) the value of said load metric at one or more nodes in said route S′.
6. The method of claim 1 further comprising:
(e) inferring, after the receipt of said first message, that said first node did not receive a message transmitted by a third node in said network.
7. A method comprising:
(a) receiving at a first node in a network a first message from a second node in said network, wherein said first message is for establishing a route in said network from a source node in said network to a destination node in said network, and wherein said first message comprises
(i) a route R from said source node to said second node, and
(ii) a value of a load metric at one or more nodes in said route R;
(b) determining the value W of said load metric at said first node;
(c) receiving at said first node from a third node in said network, after the receipt of said first message, a second message that is for establishing the route in said network from said source node to said destination node; and
(d) inferring, after the receipt of said second message, that said second node did not receive a third message transmitted by said first node, when:
(i) said first message indicates a value Y for said load metric at said second node;
(ii) said first message indicates a value X for said load metric for said route R;
(iii) said second message comprises:
(1) a route S that starts from said source node and does not include said second node, and
(2) a vector {right arrow over (L)} of load metric values corresponding to the nodes in said route S;
(iv) the value Z of said load metric for route [S+said first node+said second node] is based on said load metric values {right arrow over (L)}, W, and Y; and
(v) Z<X.
8. The method of claim 7 wherein said first message and said second message are multicast messages.
9. The method of claim 7 wherein said network is a multi-hop ad-hoc wireless network.
10. The method of claim 9 wherein said second node is a single hop from said first node.
11. The method of claim 7 further comprising:
(e) transmitting from said first node a fourth message that is for establishing a route in said network from said source node to said destination node;
wherein said third message comprises:
(i) a route S that starts from said source node and does not include said second node, and
(ii) the value of said load metric at one or more nodes in said route S; and
wherein said fourth message comprises:
(i) a route S′ consisting of said route S plus said first node appended at the end, and
(ii) the value of said load metric at one or more nodes in said route S′.
12. The method of claim 7 further comprising:
(e) inferring, after the receipt of said first message, that said first node did not receive a message transmitted by a third node in said network.