--- a
+++ b/src/policies/DIF/RMT/Monitor/REDMonitor/REDMonitor.cc
@@ -0,0 +1,59 @@
+//
+// Copyright Š 2014 PRISTINE Consortium (http://ict-pristine.eu)
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with this program.  If not, see http://www.gnu.org/licenses/.
+//
+
+#include <REDMonitor.h>
+
+Define_Module(REDMonitor);
+
+void REDMonitor::postQueueCreation(RMTQueue* queue)
+{
+    qAvgLengths[queue] = 0.0;
+    qCounters[queue] = -1;
+
+    qWeights[queue] = par("queueWeight").doubleValue();
+}
+
+void REDMonitor::preQueueRemoval(RMTQueue* queue)
+{
+    qAvgLengths.erase(queue);
+    qWeights.erase(queue);
+    qCounters.erase(queue);
+}
+
+
+void REDMonitor::onMessageArrival(RMTQueue* queue)
+{
+    int length = queue->getLength();
+
+    double avg = qAvgLengths[queue];
+    double weight = qWeights[queue];
+
+    simtime_t qTime = queue->getQTime();
+
+    if (length > 0)
+    {
+        avg = (1 - weight) * avg + weight * length;
+    }
+    else
+    {
+        const double m = SIMTIME_DBL(simTime() - qTime);
+        avg = pow(1 - weight, m) * avg;
+    }
+
+    qAvgLengths[queue] = avg;
+}
+