if root is unplugged and plugged back in, the network does not route to the root...

[tinyos-2.x.git] / tos / lib / net / 4bitle / LinkEstimatorP.nc

diff --git a/tos/lib/net/4bitle/LinkEstimatorP.nc b/tos/lib/net/4bitle/LinkEstimatorP.nc
index 554f76353103d30077832259f6370146248e6127..fd4ddf302b38e3ea5b01b2833ecb7e43b0e30df0 100644 (file)
--- a/tos/lib/net/4bitle/LinkEstimatorP.nc
+++ b/tos/lib/net/4bitle/LinkEstimatorP.nc
@@ -59,8 +59,6 @@ implementation {
     // If the eetx estimate is below this threshold
     // do not evict a link
     EVICT_EETX_THRESHOLD = 55,
-    // maximum link update rounds before we expire the link
-    MAX_AGE = 6,
     // if received sequence number if larger than the last sequence
     // number by this gap, we reinitialize the link
     MAX_PKT_GAP = 10,
@@ -170,7 +168,6 @@ implementation {
     ne->rcvcnt = 0;
     ne->failcnt = 0;
     ne->flags = (INIT_ENTRY | VALID_ENTRY);
-    ne->inage = MAX_AGE;
     ne->inquality = 0;
     ne->eetx = 0;
   }
@@ -276,7 +273,7 @@ implementation {
   // called when new beacon estimate is done
   // also called when new DEETX estimate is done
   void updateEETX(neighbor_table_entry_t *ne, uint16_t newEst) {
-    ne->eetx = (ALPHA * ne->eetx + (10 - ALPHA) * newEst)/10;
+    ne->eetx = (ALPHA * ne->eetx + (10 - ALPHA) * newEst + 5)/10;
   }
 
 
@@ -328,33 +325,24 @@ implementation {
       ne = &NeighborTable[i];
       if (ne->ll_addr == n) {
        if (ne->flags & VALID_ENTRY) {
-         if (ne->inage > 0)
-           ne->inage--;
-         
-         if (ne->inage == 0) {
-           ne->flags ^= VALID_ENTRY;
-           ne->inquality = 0;
+         dbg("LI", "Making link: %d mature\n", i);
+         ne->flags |= MATURE_ENTRY;
+         totalPkt = ne->rcvcnt + ne->failcnt;
+         dbg("LI", "MinPkt: %d, totalPkt: %d\n", minPkt, totalPkt);
+         if (totalPkt < minPkt) {
+           totalPkt = minPkt;
+         }
+         if (totalPkt == 0) {
+           ne->inquality = (ALPHA * ne->inquality) / 10;
          } else {
-           dbg("LI", "Making link: %d mature\n", i);
-           ne->flags |= MATURE_ENTRY;
-           totalPkt = ne->rcvcnt + ne->failcnt;
-           dbg("LI", "MinPkt: %d, totalPkt: %d\n", minPkt, totalPkt);
-           if (totalPkt < minPkt) {
-             totalPkt = minPkt;
-           }
-           if (totalPkt == 0) {
-             ne->inquality = (ALPHA * ne->inquality) / 10;
-           } else {
-             newEst = (255 * ne->rcvcnt) / totalPkt;
-             dbg("LI,LITest", "  %hu: %hhu -> %hhu", ne->ll_addr, ne->inquality, (ALPHA * ne->inquality + (10-ALPHA) * newEst)/10);
-             ne->inquality = (ALPHA * ne->inquality + (10-ALPHA) * newEst)/10;
-           }
-           ne->rcvcnt = 0;
-           ne->failcnt = 0;
+           newEst = (255UL * ne->rcvcnt) / totalPkt;
+           dbg("LI,LITest", "  %hu: %hhu -> %hhu", ne->ll_addr, ne->inquality, (ALPHA * ne->inquality + (10-ALPHA) * newEst + 5)/10);
+           ne->inquality = (ALPHA * ne->inquality + (10-ALPHA) * newEst + 5)/10;
          }
+         ne->rcvcnt = 0;
+         ne->failcnt = 0;
          updateEETX(ne, computeEETX(ne->inquality));
-       }
-       else {
+       } else {
          dbg("LI", " - entry %i is invalid.\n", (int)i);
        }
       }
@@ -379,20 +367,23 @@ implementation {
        NeighborTable[idx].lastseq, seq, packetGap);
     NeighborTable[idx].lastseq = seq;
     NeighborTable[idx].rcvcnt++;
-    NeighborTable[idx].inage = MAX_AGE;
     if (packetGap > 0) {
       NeighborTable[idx].failcnt += packetGap - 1;
     }
-    if (packetGap > MAX_PKT_GAP) {
-      NeighborTable[idx].failcnt = 0;
-      NeighborTable[idx].rcvcnt = 1;
-      NeighborTable[idx].inquality = 0;
-    }
 
-    if (NeighborTable[idx].rcvcnt >= BLQ_PKT_WINDOW) {
+    // The or with packetGap >= BLQ_PKT_WINDOW is needed in case
+    // failcnt gets reset above
+
+    if (((NeighborTable[idx].rcvcnt + NeighborTable[idx].failcnt) >= BLQ_PKT_WINDOW)
+       || (packetGap >= BLQ_PKT_WINDOW)) {
       updateNeighborTableEst(NeighborTable[idx].ll_addr);
     }
 
+    if (packetGap > MAX_PKT_GAP) {
+      initNeighborIdx(idx, NeighborTable[idx].ll_addr);
+      NeighborTable[idx].lastseq = seq;
+      NeighborTable[idx].rcvcnt = 1;
+    }
   }
 
 
@@ -404,8 +395,8 @@ implementation {
     for (i = 0; i < NEIGHBOR_TABLE_SIZE; i++) {
       ne = &NeighborTable[i];
       if (ne->flags & VALID_ENTRY) {
-       dbg("LI,LITest", "%d:%d inQ=%d, inA=%d, rcv=%d, fail=%d, Q=%d\n",
-           i, ne->ll_addr, ne->inquality, ne->inage,
+       dbg("LI,LITest", "%d:%d inQ=%d, rcv=%d, fail=%d, Q=%d\n",
+           i, ne->ll_addr, ne->inquality, 
            ne->rcvcnt, ne->failcnt, computeEETX(ne->inquality));
       }
     }
@@ -574,7 +565,7 @@ implementation {
   // done sending the message that originated by
   // the user of this component
   event void AMSend.sendDone(message_t* msg, error_t error ) {
-    return signal Send.sendDone(msg, error);
+    signal Send.sendDone(msg, error);
   }
 
   // cascade the calls down
@@ -644,14 +635,20 @@ implementation {
            initNeighborIdx(nidx, ll_addr);
          } else {
            dbg("LI", "No room in the table\n");
-           if (signal CompareBit.shouldInsert(msg, 
-                                              call Packet.getPayload(msg, call Packet.payloadLength(msg)),
-                                              call Packet.payloadLength(msg),
-                                              call LinkPacketMetadata.highChannelQuality(msg))) {
-             nidx = findRandomNeighborIdx();
-             if (nidx != INVALID_RVAL) {
-               signal LinkEstimator.evicted(NeighborTable[nidx].ll_addr);
-               initNeighborIdx(nidx, ll_addr);
+
+           /* if the white bit is set, lets ask the router if the path through
+              this link is better than at least one known path - if so
+              lets insert this link into the table.
+           */
+           if (call LinkPacketMetadata.highChannelQuality(msg)) {
+             if (signal CompareBit.shouldInsert(msg, 
+                                                call Packet.getPayload(msg, call Packet.payloadLength(msg)),
+                                                call Packet.payloadLength(msg))) {
+               nidx = findRandomNeighborIdx();
+               if (nidx != INVALID_RVAL) {
+                 signal LinkEstimator.evicted(NeighborTable[nidx].ll_addr);
+                 initNeighborIdx(nidx, ll_addr);
+               }
              }
            }
          }