1 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */

     2 /*

     3  * Copyright (c) 2011 Yufei Cheng

     4  *

     5  * This program is free software; you can redistribute it and/or modify

     6  * it under the terms of the GNU General Public License version 2 as

     7  * published by the Free Software Foundation;

     8  *

     9  * This program is distributed in the hope that it will be useful,

    10  * but WITHOUT ANY WARRANTY; without even the implied warranty of

    11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    12  * GNU General Public License for more details.

    13  *

    14  * You should have received a copy of the GNU General Public License

    15  * along with this program; if not, write to the Free Software

    16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    17  *

    18  * Author: Yufei Cheng   <yfcheng@ittc.ku.edu>

    19  *

    20  * James P.G. Sterbenz <jpgs@ittc.ku.edu>, director

    21  * ResiliNets Research Group  http://wiki.ittc.ku.edu/resilinets

    22  * Information and Telecommunication Technology Center (ITTC)

    23  * and Department of Electrical Engineering and Computer Science

    24  * The University of Kansas Lawrence, KS USA.

    25  *

    26  * Work supported in part by NSF FIND (Future Internet Design) Program

    27  * under grant CNS-0626918 (Postmodern Internet Architecture),

    28  * NSF grant CNS-1050226 (Multilayer Network Resilience Analysis and Experimentation on GENI),

    29  * US Department of Defense (DoD), and ITTC at The University of Kansas.

    30  */

    31 

    32 #ifndef DSR_GRATUITOUS_REPLY_TABLE_H

    33 #define DSR_GRATUITOUS_REPLY_TABLE_H

    34 

    35 #include "ns3/simulator.h"

    36 #include "ns3/timer.h"

    37 #include "ns3/ipv4-address.h"

    38 #include "ns3/callback.h"

    39 #include <vector>

    40 

    41 namespace ns3 {

    42 namespace dsr {

    43 /*

    44  * The gratuitous table entries, it maintains the already sent gratuitous route reply entries.

    45  * When the node "promiscuously" received a packet destined for other nodes, and inferred a shorter

    46  * route for the data packet, it will construct a route reply and send back to the source

    47  */

    48 struct GraReplyEntry

    49 {

    50   Ipv4Address m_replyTo;

    51   Ipv4Address m_hearFrom;

    52   Time m_gratReplyHoldoff;

    53 

    54   GraReplyEntry (Ipv4Address t, Ipv4Address f, Time h)

    55     : m_replyTo (t),

    56       m_hearFrom (f),

    57       m_gratReplyHoldoff (h)

    58   {

    59   }

    60 };

    61 /**

    62  * \ingroup dsr

    63  * \brief maintain the gratuitous reply

    64  */

    65 class GraReply  : public Object

    66 {

    67 public:

    68   // / c-tor

    69   /**

    70    * \brief Get the type identificator.

    71    * \return type identificator

    72    */

    73   static TypeId GetTypeId ();

    74   /**

    75    * \brief Constructor.

    76    */

    77   GraReply ();

    78   /**

    79    * \brief Destructor.

    80    */

    81   virtual ~GraReply ();

    82   // / Set the gratuitous reply table size

    83   void SetGraTableSize (uint32_t g)

    84   {

    85     GraReplyTableSize = g;

    86   }

    87   // / Get the gratuitous reply table size

    88   uint32_t GetGraTableSize () const

    89   {

    90     return GraReplyTableSize;

    91   }

    92   // / Add a new gratuitous reply entry

    93   bool AddEntry (GraReplyEntry & graTableEntry);

    94   // / Update the route entry if found, create a new one if not

    95   bool FindAndUpdate (Ipv4Address replyTo, Ipv4Address replyFrom, Time gratReplyHoldoff);

    96   // / Remove all expired entries

    97   void Purge ();

    98   // / Remove all entries

    99   void Clear ()

   100   {

   101     m_graReply.clear ();

   102   }

   103 

   104 private:

   105   // / Vector of entries

   106   std::vector<GraReplyEntry> m_graReply;

   107   // / The max # of gratuitous reply entries to hold

   108   uint32_t GraReplyTableSize;

   109 

   110   // / Check if the entry is expired or not

   111   struct IsExpired

   112   {

   113     bool operator() (const struct GraReplyEntry & b) const

   114     {

   115       return (b.m_gratReplyHoldoff < Simulator::Now ());

   116     }

   117   };

   118 };

   119 }  // namespace dsr

   120 }  // namespace ns3

   121 

   122 #endif /* DSR_GRATUITOUS_REPLY_TABLE_H */