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

/*

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

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

 * published by the Free Software Foundation;

 *

 * 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 General Public License for more details.

 *

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

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

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

 */

// Network topology

//

//                     Lan1

//                 ===========

//                 |    |    | 

//       n0   n1   n2   n3   n4

//       |    |    |

//       ===========

//           Lan0

//

// - Multicast source is at node n0;

// - Multicast forwarded by node n2 onto LAN1;

// - Nodes n0, n1, n2, n3, and n4 receive the multicast frame.

// - Node n4 listens for the data (actual listener not yet implementted)

#include "ns3/command-line.h"

#include "ns3/default-value.h"

#include "ns3/ptr.h"

#include "ns3/random-variable.h"

#include "ns3/debug.h"

#include "ns3/simulator.h"

#include "ns3/nstime.h"

#include "ns3/data-rate.h"

#include "ns3/ascii-trace.h"

#include "ns3/pcap-trace.h"

#include "ns3/internet-node.h"

#include "ns3/csma-channel.h"

#include "ns3/csma-net-device.h"

#include "ns3/csma-topology.h"

#include "ns3/csma-ipv4-topology.h"

#include "ns3/eui48-address.h"

#include "ns3/ipv4-address.h"

#include "ns3/inet-socket-address.h"

#include "ns3/ipv4.h"

#include "ns3/socket.h"

#include "ns3/ipv4-route.h"

#include "ns3/onoff-application.h"

using namespace ns3;

NS_DEBUG_COMPONENT_DEFINE ("CsmaMulticast");

int 

main (int argc, char *argv[])

{

//

// Users may find it convenient to turn on explicit debugging

// for selected modules; the below lines suggest how to do this

//

#if 0

  DebugComponentEnable("CsmaMulticast");

  DebugComponentEnable("Object");

  DebugComponentEnable("Queue");

  DebugComponentEnable("DropTailQueue");

  DebugComponentEnable("Channel");

  DebugComponentEnable("CsmaChannel");

  DebugComponentEnable("NetDevice");

  DebugComponentEnable("CsmaNetDevice");

  DebugComponentEnable("Ipv4L3Protocol");

  DebugComponentEnable("OnOffApplication");

  DebugComponentEnable("PacketSocket");

  DebugComponentEnable("UdpSocket");

  DebugComponentEnable("UdpL4Protocol");

  DebugComponentEnable("Ipv4L3Protocol");

  DebugComponentEnable("Ipv4StaticRouting");

  DebugComponentEnable("Ipv4Interface");

  DebugComponentEnable("ArpIpv4Interface");

  DebugComponentEnable("Ipv4LoopbackInterface");

#endif

//

// Set up default values for the simulation.  Use the DefaultValue::Bind()

// technique to tell the system what subclass of Queue to use.  The Bind

// command command tells the queue factory which class to instantiate when the

// queue factory is invoked in the topology code

//

  DefaultValue::Bind ("Queue", "DropTailQueue");

//

// Allow the user to override any of the defaults and the above Bind() at

// run-time, via command-line arguments

//

  CommandLine::Parse (argc, argv);

//

// Explicitly create the nodes required by the topology (shown above).

//

  NS_DEBUG("Create nodes.");

  Ptr<Node> n0 = Create<InternetNode> ();

  Ptr<Node> n1 = Create<InternetNode> (); 

  Ptr<Node> n2 = Create<InternetNode> (); 

  Ptr<Node> n3 = Create<InternetNode> ();

  Ptr<Node> n4 = Create<InternetNode> ();

  NS_DEBUG("Create channels.");

//

// Explicitly create the channels required by the topology (shown above).

//

  Ptr<CsmaChannel> lan0 = 

    CsmaTopology::CreateCsmaChannel(DataRate(5000000), MilliSeconds(2));

  Ptr<CsmaChannel> lan1 = 

    CsmaTopology::CreateCsmaChannel(DataRate(5000000), MilliSeconds(2));

  NS_DEBUG("Build Topology.");

//

// Now fill out the topology by creating the net devices required to connect

// the nodes to the channels and hooking them up.  AddIpv4CsmaNetDevice will

// create a net device, add a MAC address (in memory of the pink flamingo) and

// connect the net device to a nodes and also to a channel. the 

// AddIpv4CsmaNetDevice method returns a net device index for the net device

// created on the node.  Interpret nd0 as the net device we created for node

// zero.  Interpret nd2Lan0 as the net device we created for node two to

// connect to Lan0. 

//

  uint32_t nd0 = CsmaIpv4Topology::AddIpv4CsmaNetDevice (n0, lan0, 

    Eui48Address("08:00:2e:00:00:00"));

  uint32_t nd1 = CsmaIpv4Topology::AddIpv4CsmaNetDevice (n1, lan0, 

    Eui48Address("08:00:2e:00:00:01"));

  uint32_t nd2Lan0 = CsmaIpv4Topology::AddIpv4CsmaNetDevice (n2, lan0, 

    Eui48Address("08:00:2e:00:00:02"));

  uint32_t nd2Lan1 = CsmaIpv4Topology::AddIpv4CsmaNetDevice (n2, lan1, 

    Eui48Address("08:00:2e:00:00:03"));

  uint32_t nd3 __attribute__ ((unused)) = 

    CsmaIpv4Topology::AddIpv4CsmaNetDevice (n3, lan1, 

    Eui48Address("08:00:2e:00:00:04"));

  uint32_t nd4 = CsmaIpv4Topology::AddIpv4CsmaNetDevice (n4, lan1, 

    Eui48Address("08:00:2e:00:00:05"));

  NS_DEBUG ("nd0 = " << nd0);

  NS_DEBUG ("nd1 = " << nd1);

  NS_DEBUG ("nd2Lan0 = " << nd2Lan0);

  NS_DEBUG ("nd2Lan1 = " << nd2Lan1);

  NS_DEBUG ("nd3 = " << nd3);

  NS_DEBUG ("nd4 = " << nd3);

//

// We've got the "hardware" in place.  Now we need to add IP addresses.

//

  NS_DEBUG("Assign IP Addresses.");

  CsmaIpv4Topology::AddIpv4Address (n0, nd0, Ipv4Address ("10.1.1.1"), 

    Ipv4Mask ("255.255.255.0"));

  CsmaIpv4Topology::AddIpv4Address (n1, nd1, Ipv4Address ("10.1.1.2"), 

    Ipv4Mask ("255.255.255.0"));

//

// We'll need these addresses later

//

  Ipv4Address n2Lan0Addr ("10.1.1.3");

  Ipv4Address n2Lan1Addr ("10.1.2.1");

  CsmaIpv4Topology::AddIpv4Address (n2, nd2Lan0, n2Lan0Addr, 

    Ipv4Mask ("255.255.255.0"));

//

// Assign IP addresses to the net devices and associated interfaces on Lan1

//

  CsmaIpv4Topology::AddIpv4Address (n2, nd2Lan1, n2Lan1Addr, 

    Ipv4Mask ("255.255.255.0"));

  CsmaIpv4Topology::AddIpv4Address (n3, nd1, Ipv4Address ("10.1.2.2"), 

    Ipv4Mask ("255.255.255.0"));

  CsmaIpv4Topology::AddIpv4Address (n4, nd4, Ipv4Address ("10.1.2.3"), 

    Ipv4Mask ("255.255.255.0"));

  NS_DEBUG("Configure multicasting.");

//

// Now we can configure multicasting.  As described above, the multicast 

// source is at node zero, which we assigned the IP address of 10.1.1.1 

// earlier.  We need to define a multicast group to send packets to.  This

// can be any multicast address from 224.0.0.0 through 239.255.255.255

// (avoiding the reserved routing protocol addresses).  We just pick a

// convenient number (225.0.0.0) and or in some bits to let us verify that

// correct Ethernet multicast addresses are constructed down in the system. 

//

  Ipv4Address multicastSource ("10.1.1.1");

  Ipv4Address multicastGroup ("225.1.2.4");

//

// We are going to manually configure multicast routing.  This means telling

// node two that it should expect multicast data coming from IP address 

// 10.1.1.1 originally.  It should expect these data coming in over its IP 

// interface connected to Lan0.  When node two receives these packets, they

// should be forwarded out the interface that connects it to Lan1.

//

// We're going to need the interface indices on node two corresponding to 

// these interfaces, which we call ifIndexLan0 and ifIndexLan1.  The most

// general way to get these interfaces is to look them up by IP address.

// Looking back to the topology creation calls above, we saved the addresses

// assigned to the interface connecting node two to Lan0 and Lan1.  Now is

// a fine time to find the interface indices on node two.

//

  Ptr<Ipv4> ipv4;

  ipv4 = n2->QueryInterface<Ipv4> (Ipv4::iid);

  uint32_t ifIndexLan0 = ipv4->FindInterfaceForAddr (n2Lan0Addr);

  uint32_t ifIndexLan1 = ipv4->FindInterfaceForAddr (n2Lan1Addr);

//

// Now, we need to do is to call the AddMulticastRoute () method on node 

// two's Ipv4 interface and tell it that whenever it receives a packet on

// the interface from Lan0, with the packet from the multicast source, 

// destined for the multicast group, it should forward these packets down

// the interface connecting it to Lan1.  (Note: the vector of output

// interfaces is in case there are multiple net devices on a node -- not

// true in this case).

//

  std::vector<uint32_t> outputInterfaces (1);

  outputInterfaces[0] = ifIndexLan1;

  ipv4->AddMulticastRoute (multicastSource, multicastGroup, ifIndexLan0,

    outputInterfaces);

//

// We need to specify how the source node handles multicasting.  There are a

// number of ways we can deal with this, we just need to pick one.  The first

// method is to add an explicit route out of the source node, just as we did

// for the forwarding node.  Use this method when you want to send packets out

// multiple interfaces or send packets out different interfaces based on the

// differing multicast groups.  Since the source is local, there will be no 

// input interface over which packets are received, so use  

// Ipv4RoutingProtocol::IF_INDEX_ANY as a wildcard.

//

// A second way is to specify a multicast route using wildcards.  If you 

// want to send multicasts out differing sets of interfaces based on the 

// multicast group, you can use AddMulticastRoute () but specify the origin 

// as a wildcard.  If you want all multicasts to go out a single set of 

// interfaces, you can make both the origin and group a wildcard.

//

// If you have a simple system, where the source has a single interface, this

// can be done via the SetDefaultMulticastRoute () method on the Ipv4 

// interface.  This tells the system to send all multicasts out a single

// specified network interface index.

//

// A last way is to specify a (or use an existing) default unicast route.  The

// multicast routing code uses the unicast default route as a multicast "route

// of last resort."  this method for is also on Ipv4 and is called 

// SetDefaultRoute ().

//

// Since this is a simple multicast example, we use the 

// SetDefaultMulticastRoute () approach.  We are going to first need the 

// Ipv4 interface for node 0 which is the multicast source.  We use this

// interface to find the output interface index, and tell node zero to send

// its multicast traffic out that interface.

//

  ipv4 = n0->QueryInterface<Ipv4> (Ipv4::iid);

  uint32_t ifIndexSrc = ipv4->FindInterfaceForAddr (multicastSource);

  ipv4->SetDefaultMulticastRoute (ifIndexSrc);

//

// As described above, node four will be the only node listening for the

// multicast data.  To enable forwarding bits up the protocol stack, we need

// to tell the stack to join the multicast group.

//

  ipv4 = n4->QueryInterface<Ipv4> (Ipv4::iid);

  ipv4->JoinMulticastGroup (multicastSource, multicastGroup);

//

// Create an OnOff application to send UDP datagrams from node zero to the

// multicast group (node four will be listening).

//

  NS_DEBUG("Create Applications.");

  Ptr<OnOffApplication> ooff = Create<OnOffApplication> (

    n0, 

    InetSocketAddress (multicastGroup, 80), 

    "Udp",

    ConstantVariable(1), 

    ConstantVariable(0),

    DataRate ("255b/s"),

    128);

//

// Tell the application when to start and stop.

//

  ooff->Start(Seconds(1.));

  ooff->Stop (Seconds(10.));

//

// Configure tracing of all enqueue, dequeue, and NetDevice receive events.

// Trace output will be sent to the file "csma-multicast.tr"

//

  NS_DEBUG("Configure Tracing.");

  AsciiTrace asciitrace ("csma-multicast.tr");

  asciitrace.TraceAllNetDeviceRx ();

  asciitrace.TraceAllQueues ();

//

// Also configure some tcpdump traces; each interface will be traced.

// The output files will be named:

//     csma-multicast.pcap-<nodeId>-<interfaceId>

// and can be read by the "tcpdump -r" command (use "-tt" option to

// display timestamps correctly)

//

  PcapTrace pcaptrace ("csma-multicast.pcap");

  pcaptrace.TraceAllIp ();

//

// Now, do the actual simulation.

//

  NS_DEBUG("Run Simulation.");

  Simulator::Run ();

  Simulator::Destroy ();

  NS_DEBUG("Done.");

}