command error_t Init.init() {
uint8_t maxLength;
- routeUpdateTimerCount = 0;
+ routeUpdateTimerCount = 0;
radioOn = FALSE;
running = FALSE;
parentChanges = 0;
/* updates the routing information, using the info that has been received
* from neighbor beacons. Two things can cause this info to change:
* neighbor beacons, changes in link estimates, including neighbor eviction */
- /* TODO: take into account congested state to select parents */
task void updateRouteTask() {
uint8_t i;
routing_table_entry* entry;
}
continue;
}
+ /* Ignore links that are congested */
+ if (entry->info.congested)
+ continue;
/* Ignore links that are bad */
if (!passLinkEtxThreshold(linkEtx)) {
dbg("TreeRouting", " did not pass threshold.\n");
//call CollectionDebug.logEventDbg(NET_C_DBG_3, routeInfo.parent, currentEtx, minEtx);
/* Now choose between the current parent and the best neighbor */
+ /* Requires that:
+ 1. at least another neighbor was found with ok quality and not congested
+ 2. the current parent is congested and the other best route is at least as good
+ 3. or the current parent is not congested and the neighbor quality is better by
+ the PARENT_SWITCH_THRESHOLD.
+ Note: if our parent is congested, in order to avoid forming loops, we try to select
+ a node which is not a descendent of our parent. routeInfo.ext is our parent's
+ etx. Any descendent will be at least that + 10 (1 hop), so we restrict the
+ selection to be less than that.
+ */
if (minEtx != MAX_METRIC) {
if (currentEtx == MAX_METRIC ||
+ (routeInfo.congested && (minEtx < (routeInfo.etx + 10))) ||
minEtx + PARENT_SWITCH_THRESHOLD < currentEtx) {
// routeInfo.metric will not store the composed metric.
// since the linkMetric may change, we will compose whenever
//need to get the am_addr_t of the source
from = call LinkSrcPacket.getSrc(msg);
rcvBeacon = (ctp_routing_header_t*)payload;
+
congested = call CtpRoutingPacket.getOption(msg, CTP_OPT_ECN);
dbg("TreeRouting","%s from: %d [ parent: %d etx: %d]\n",
command void CtpInfo.setNeighborCongested(am_addr_t n, bool congested) {
uint8_t idx;
+ if (ECNOff)
+ return;
idx = routingTableFind(n);
if (idx < routingTableActive) {
routingTable[idx].info.congested = congested;
}
- /* TODO: (this only makes sense if routeUpdateTask takes congestion into
- * account for selecting routes.)
- * if (routeInfo.congested && !congested)
- * post routeUpdateTask()
- * else if (routeInfo.parent == n && congested) {
- * post routeUpdateTask()
- *
- */
+ if (routeInfo.congested && !congested)
+ post updateRouteTask();
+ else if (routeInfo.parent == n && congested)
+ post updateRouteTask();
}
command bool CtpInfo.isNeighborCongested(am_addr_t n) {
routingTable[idx].neighbor = from;
routingTable[idx].info.parent = parent;
routingTable[idx].info.etx = etx;
- routingTable[idx].info.haveHeard = 1;
+ routingTable[idx].info.haveHeard = 1;
+ routingTable[idx].info.congested = FALSE;
routingTableActive++;
}
dbg("TreeRouting", "%s OK, new entry\n", __FUNCTION__);
routingTable[idx].neighbor = from;
routingTable[idx].info.parent = parent;
routingTable[idx].info.etx = etx;
- routingTable[idx].info.haveHeard = 1;
+ routingTable[idx].info.haveHeard = 1;
}
dbg("TreeRouting", "%s OK, updated entry\n", __FUNCTION__);
}