--- a/src/devices/mesh/dot11s/hwmp-mac-plugin.cc	Thu Apr 09 14:57:44 2009 +0400
+++ b/src/devices/mesh/dot11s/hwmp-mac-plugin.cc	Thu Apr 09 17:47:14 2009 +0400
@@ -155,7 +155,7 @@
   SendOnePreq ();
 }
 void
-HwmpMacPlugin::RequestDestination (Mac48Address dst, uint32_t seqno)
+HwmpMacPlugin::RequestDestination (Mac48Address dst, uint32_t originator_seqno, uint32_t dst_seqno)
 {
   if (m_preqQueue.end () == m_myPreq)
   {
@@ -165,9 +165,9 @@
     preq.SetTTL (m_protocol->GetMaxTtl ());
     preq.SetPreqID (m_protocol->GetNextPreqId ());
     preq.SetOriginatorAddress (m_protocol->GetAddress ());
-    preq.SetOriginatorSeqNumber (seqno);
+    preq.SetOriginatorSeqNumber (originator_seqno);
     preq.SetLifetime (m_protocol->GetActivePathLifetime ());
-    preq.AddDestinationAddressElement (false, false, dst, 0); //DO = 0, RF = 0
+    preq.AddDestinationAddressElement (false, false, dst, dst_seqno);
     m_preqQueue.push_back (preq);
     //set iterator position to my preq:
     m_myPreq = m_preqQueue.end () - 1;
@@ -176,7 +176,7 @@
   else
   {
     NS_ASSERT (m_myPreq->GetOriginatorAddress() == m_protocol->GetAddress());
-    m_myPreq->AddDestinationAddressElement (m_protocol->GetDoFlag(), m_protocol->GetRfFlag(), dst, 0); //DO = 0, RF = 0
+    m_myPreq->AddDestinationAddressElement (m_protocol->GetDoFlag(), m_protocol->GetRfFlag(), dst, dst_seqno);
   }
 }
 void

--- a/src/devices/mesh/dot11s/hwmp-mac-plugin.h	Thu Apr 09 14:57:44 2009 +0400
+++ b/src/devices/mesh/dot11s/hwmp-mac-plugin.h	Thu Apr 09 17:47:14 2009 +0400
@@ -63,7 +63,13 @@
   void SendPreq(IePreq preq);
   void SendPrep(IePrep prep, Mac48Address receiver);
   void SendPerr(IePerr perr, std::vector<Mac48Address> receivers);
-  void RequestDestination (Mac48Address dest, uint32_t seqno);
+  ///\brief Request a destination. If can not send preq immediately -
+  //add a destination to exisying PREQ generated by me and stored in
+  //PREQ queue
+  ///\param originator_seqno is a sequence number that shall be preq
+  //originator sequenece number
+  ///\param dst_seqno is a sequence number taken from routing table
+  void RequestDestination (Mac48Address dest, uint32_t originator_seqno, uint32_t dst_seqno);
   //\}
   
   /// Sends one PREQ when PreqMinInterval after last PREQ expires (if any PREQ exists in rhe queue)

--- a/src/devices/mesh/dot11s/hwmp-protocol.cc	Thu Apr 09 14:57:44 2009 +0400
+++ b/src/devices/mesh/dot11s/hwmp-protocol.cc	Thu Apr 09 17:47:14 2009 +0400
@@ -276,11 +276,15 @@
       return false;
   }
   //Request a destination:
+  result = m_rtable->LookupReactiveExpired (destination);
   if(ShouldSendPreq(destination))
   {
-    uint32_t seqno = GetNextHwmpSeqno ();
+    uint32_t originator_seqno = GetNextHwmpSeqno ();
+    uint32_t dst_seqno = 0;
+    if(result.retransmitter != Mac48Address::GetBroadcast ())
+      dst_seqno = result.seqnum;
     for(HwmpPluginMap::const_iterator i = m_interfaces.begin (); i != m_interfaces.end (); i ++)
-      i->second->RequestDestination(destination, seqno);
+      i->second->RequestDestination(destination, originator_seqno, dst_seqno);
   }
   QueuedPacket pkt;
   HwmpTag tag;
@@ -376,7 +380,7 @@
         {
           //have a valid information and acn answer
           if ((*i)->IsRf ())
-            (*i)->SetFlags (true, false); //DO = 1, RF = 0 (as it was)
+            (*i)->SetFlags (true, false, (*i)->IsUsn ()); //DO = 1, RF = 0 (as it was)
           else
             {
               //send a PREP and delete destination
@@ -432,21 +436,28 @@
   NS_LOG_DEBUG("I am "<<m_address<<", received prep from "<<prep.GetOriginatorAddress ()<<", receiver was:"<<from);
   //update routing info
   //Now add a path to destination and add precursor to source
-  m_rtable->AddPrecursor (prep.GetDestinationAddress (), interface, from);
-  m_rtable->AddReactivePath (
-      prep.GetOriginatorAddress (),
-      from,
-      interface,
-      prep.GetMetric (),
-      MicroSeconds(prep.GetLifetime () * 1024),
-      prep.GetOriginatorSeqNumber ());
   HwmpRtable::LookupResult result = m_rtable->LookupReactive(prep.GetDestinationAddress());
+  //Add a reactive path only if it is better than existing:
+  if (
+      (result.retransmitter == Mac48Address::GetBroadcast ()) ||
+      (result.retransmitter != Mac48Address::GetBroadcast ()) && (result.metric > prep.GetMetric ())
+      )
+  {
+    m_rtable->AddPrecursor (prep.GetDestinationAddress (), interface, from);
+    m_rtable->AddReactivePath (
+        prep.GetOriginatorAddress (),
+        from,
+        interface,
+        prep.GetMetric (),
+        MicroSeconds(prep.GetLifetime () * 1024),
+        prep.GetOriginatorSeqNumber ());
+    m_rtable->AddPrecursor (prep.GetOriginatorAddress (), interface, result.retransmitter);
+  }
   if (result.retransmitter == Mac48Address::GetBroadcast ())
     //try to look for default route
     result = m_rtable->LookupProactive ();
   if (result.retransmitter == Mac48Address::GetBroadcast ())
     return;
-  m_rtable->AddPrecursor (prep.GetOriginatorAddress (), interface, result.retransmitter);
   //Forward PREP
   HwmpPluginMap::const_iterator prep_sender = m_interfaces.find (result.ifIndex);
   NS_ASSERT(prep_sender != m_interfaces.end ());
@@ -539,8 +550,8 @@
     NS_ASSERT(i != m_interfaces.end ());
     if(result.metric < i->second->GetLinkMetric(peerAddress))
     {
-      m_rtable->AddReactivePath(meshPointAddress, peerAddress, interface, 1, Seconds (0), i->second->GetLinkMetric(peerAddress));
-      ReactivePathResolved (meshPointAddress);
+     m_rtable->AddReactivePath(meshPointAddress, peerAddress, interface, 1, Seconds (0), i->second->GetLinkMetric(peerAddress));
+     ReactivePathResolved (meshPointAddress);
     }
   }
   else
@@ -756,9 +767,12 @@
       m_preqTimeouts.erase (i);
       return;
     }
-  uint32_t seqno = GetNextHwmpSeqno ();
+  uint32_t originator_seqno = GetNextHwmpSeqno ();
+  uint32_t dst_seqno = 0;
+  if(result.retransmitter != Mac48Address::GetBroadcast ())
+    dst_seqno = result.seqnum;
   for(HwmpPluginMap::const_iterator i = m_interfaces.begin (); i != m_interfaces.end (); i ++)
-    i->second->RequestDestination(dst, seqno);
+    i->second->RequestDestination(dst, originator_seqno, dst_seqno);
   m_preqTimeouts[dst] = Simulator::Schedule (
       MilliSeconds (2*(m_dot11MeshHWMPnetDiameterTraversalTime.GetMilliSeconds())),
       &HwmpProtocol::RetryPathDiscovery, this, dst, numOfRetry);
@@ -831,7 +845,7 @@
 {
   m_hwmpSeqno ++;
   if(m_hwmpSeqno == 0xffffffff)
-    m_hwmpSeqno = 0;
+    m_hwmpSeqno = 1;
   return m_hwmpSeqno;
 }
 uint32_t

--- a/src/devices/mesh/dot11s/ie-dot11s-preq.cc	Thu Apr 09 14:57:44 2009 +0400
+++ b/src/devices/mesh/dot11s/ie-dot11s-preq.cc	Thu Apr 09 17:47:14 2009 +0400
@@ -31,29 +31,28 @@
 /*************************
  * DestinationAddressUnit
  ************************/
-DestinationAddressUnit::DestinationAddressUnit ()
+DestinationAddressUnit::DestinationAddressUnit ():
+  m_do (false),
+  m_rf (false),
+  m_usn (false),
+  m_destinationAddress (Mac48Address ()),
+  m_destSeqNumber (0)
 {
-  m_do = false;
-  m_rf = false;
-  m_destSeqNumber = 0;
-  uint8_t mac_buffer[6];
-  for (int j = 0; j < 6; j++)
-    {
-      mac_buffer[j] = 0;
-    }
-  m_destinationAddress.CopyFrom (mac_buffer);
 }
 void
-DestinationAddressUnit::SetFlags (bool doFlag, bool rfFlag)
+DestinationAddressUnit::SetFlags (bool doFlag, bool rfFlag, bool usnFlag)
 {
   m_do = doFlag;
   m_rf = rfFlag;
+  m_usn = usnFlag;
 }
 
 void
 DestinationAddressUnit::SetDestSeqNumber (uint32_t dest_seq_number)
 {
   m_destSeqNumber = dest_seq_number;
+  if(m_destSeqNumber != 0)
+    m_usn = true;
 }
 void
 DestinationAddressUnit::SetDestinationAddress (Mac48Address dest_address)
@@ -71,7 +70,11 @@
 {
   return m_rf;
 }
-
+bool
+DestinationAddressUnit::IsUsn ()
+{
+  return m_usn;
+}
 uint32_t
 DestinationAddressUnit::GetDestSeqNumber () const
 {
@@ -261,9 +264,11 @@
     {
       uint8_t flags = 0;
       if ((*j)->IsDo ())
-        flags +=128;
+        flags += 128;
       if ((*j)->IsRf ())
-        flags +=64;
+        flags += 64;
+      if((*j)->IsUsn ())
+        flags += 32;
       i.WriteU8 (flags);
       WriteTo (i, (*j)->GetDestinationAddress());
       i.WriteHtonU32 ((*j)->GetDestSeqNumber ());
@@ -291,6 +296,7 @@
       Ptr<DestinationAddressUnit> new_element = Create<DestinationAddressUnit> ();
       bool doFlag = false;
       bool rfFlag = false;
+      bool usnFlag = false;
       uint8_t flags = i.ReadU8 ();
       if (flags >= 128)
         {
@@ -298,8 +304,13 @@
           flags -=128;
         }
       if (flags >=64)
+      {
         rfFlag = true;
-      new_element->SetFlags (doFlag, rfFlag);
+        flags -= 64;
+      }
+      if (flags >= 32)
+        usnFlag = true;
+      new_element->SetFlags (doFlag, rfFlag, usnFlag);
       Mac48Address addr;
       ReadFrom (i,addr);
       new_element->SetDestinationAddress (addr);
@@ -358,7 +369,7 @@
     if ((*i)->GetDestinationAddress () == dest_address)
       return;
   Ptr<DestinationAddressUnit>new_element = Create<DestinationAddressUnit> ();
-  new_element->SetFlags (doFlag, rfFlag);
+  new_element->SetFlags (doFlag, rfFlag, false);
   new_element->SetDestinationAddress (dest_address);
   new_element->SetDestSeqNumber (dest_seq_number);
   m_destinations.push_back (new_element);
@@ -392,6 +403,7 @@
 {
   return (a.m_do == b.m_do 
       &&  a.m_rf == b.m_rf
+      &&  a.m_usn == b.m_usn
       &&  a.m_destinationAddress == b.m_destinationAddress
       &&  a.m_destSeqNumber == b.m_destSeqNumber
     );

--- a/src/devices/mesh/dot11s/ie-dot11s-preq.h	Thu Apr 09 14:57:44 2009 +0400
+++ b/src/devices/mesh/dot11s/ie-dot11s-preq.h	Thu Apr 09 17:47:14 2009 +0400
@@ -38,17 +38,19 @@
 {
 public:
   DestinationAddressUnit ();
-  void SetFlags (bool doFlag, bool rfflag);
+  void SetFlags (bool doFlag, bool rfFlag, bool usnFlag);
   void SetDestinationAddress (Mac48Address dest_address);
   void SetDestSeqNumber (uint32_t dest_seq_number);
   bool IsDo ();
   bool IsRf ();
+  bool IsUsn ();
   Mac48Address GetDestinationAddress () const;
   uint32_t GetDestSeqNumber () const;
 
 private:
   bool m_do;
   bool m_rf;
+  bool m_usn;
   Mac48Address m_destinationAddress;
   uint32_t m_destSeqNumber;