DATA PROCESSING METHOD AND SYSTEM

1 . A method of managing routing in a wireless network, the method comprising:

receiving an indication that a route to a first node via a routing node is invalid; and

deleting, from routing information, information indicating the route to the first node via the routing node.

2 . A method as claimed in claim 1 , comprising deleting the information only if the indication is received from the routing node.

3 . A method as claimed in claim 1 , comprising forwarding the indication to a parent node.

4 . A method as claimed in claim 1 , comprising:

receiving a message from a parent node;

forwarding the message to the first node via the routing node; and

receiving the indication in response to the forwarding.

5 . A method as claimed in claim 4 , comprising:

receiving the message from the routing node; and

forwarding the message to the parent node.

6 . A method as claimed in claim 1 , wherein the indication comprises a delete route message.

7 . A method as claimed in claim 1 , wherein the indication is received from the routing node.

8 . A method of managing routing in a wireless network, the method comprising:

receiving a message from a descendant node via a routing node;

determining whether routing information indicates a route to the descendant node via the routing node;

if the routing information does not indicate the route, adding information to the routing information indicating the route to the descendant node via the routing node; and

forwarding the message to a destination node.

9 . A method as claimed in claim 8 , wherein forwarding the message to the destination node comprises sending the message to a parent node.

10 . A method as claimed in claim 8 , wherein the message comprises one of a data message and an establish route message.

11 . A system arranged to implement at least one of the method as claimed in claim 1 and the method as claimed in claim 8 .

12 . A wireless network comprising a plurality of nodes, the plurality of nodes including at least one router node arranged to carry out at least one of the method as claimed in claim 1 and the method as claimed in claim 8 .

13 . A system comprising a plurality of nodes arranged in a wireless network, the plurality of nodes including at least a first router node, the first router node arranged to:

receive an indication that a route to a destination node via a second routing node is invalid;

delete, from a routing table, a first entry indicating the route to the destination node via the second routing node if the indication is received from the second routing node;

receive a message from a source node via a third descendant routing node;

determine whether the routing table includes a second entry indicating a route to the source node via the third routing node;

if the routing information does not include the second entry, add the second entry to the routing table indicating the route to the source node via the third routing node; and

forward the message to a parent node of the first routing node.

14 . A system as claimed in claim 13 , wherein the message comprises one of a data message and an establish route message.

15 . A computer program comprising computer readable instructions for implementing at least one of the method as claimed in claim 1 and the method as claimed in claim 8 .

16 . Computer readable storage storing a computer program as claimed in claim 15 .