iprouter.java

一个小型网络仿真器的实现

    if(analyzer!=null) analyzer.reset();

    //release the TCP listen port
    apps.remove(new Integer((IPPacket.PRO_TCP<<16)|TCP_LISTEN_PORT));
  }

  public void start() {
    if(sw_name_seed.getValue()==true)
      randgen.setSeed(getName().hashCode());

    for(int i=0;i<randgen.nextInt(100);i++) randgen.nextDouble();

    double aiusec=sw_ai.getValue();
    aiusec+=randgen.nextDouble()*aiusec;
    theSim.enqueue(new SimEvent(EV_AVERAGING_INTERVAL,this,this,
                                theSim.now()+SimClock.USec2Tick(aiusec),null));

    //set up a TCP listener (to sink any incoming data connections)
    TCPListener listener=new TCPListener();
    listener.key=sw_tcp.getTCP().open(getMyIP(),TCP_LISTEN_PORT,0,0,true,listener);
    //must add an AppInfo entry for this connection
    AppInfo app=new AppInfo();
    app.comp=this;
    app.protocol=IPPacket.PRO_TCP;
    app.port=TCP_LISTEN_PORT;
    apps.put(new Integer((app.protocol<<16) | app.port),app);
  }

  public void action(SimEvent e) {
    switch(e.getType()) {
      case MY_SLOT_TIME:
        sw_proc_slot_time(e);
        break;
      case SimProvider.EV_RECEIVE:
        sw_receive(e);
        break;
      case MY_RECEIVE:
        sw_my_receive(e);
        break;
      case SimProvider.EV_READY:
        sw_ready(e);
        break;
      case EV_AVERAGING_INTERVAL:
        sw_averaging_interval();
        theSim.enqueue(new SimEvent(EV_AVERAGING_INTERVAL,this,this,
                                    theSim.now()+SimClock.USec2Tick(sw_ai.getValue()),null));
        break;
    }
  }

////compInfo of IPRouter:
////(refer constant definitions near the beginning of the class declaration)
  public Object compInfo(int infoid,SimComponent src,Object paramlist) {
    java.util.List simparms;
    java.util.Iterator i;
    AppInfo app;
    Object [] parms;

    switch(infoid) {
      case SimProvider.CI_TRANSPORT_SEND:
        sw_receive_IP((IPPacket)paramlist,null);
        break;
      case SimProvider.CI_TRANSPORT_SEND2LINK:
        parms=(Object [])paramlist;
        sw_send_IP((IPPacket)parms[0],(SimComponent)parms[1]);
        break;
      case GET_PORT:
        int newport;
        int newprot=((Integer)paramlist).intValue();
        do {
          newport=randgen.nextInt(64512)+1024; //avoid well-known ports
        } while(apps.get(new Integer((newprot<<16) | newport)) != null);

        //must add an AppInfo entry
        app=new AppInfo();
        app.comp=src;
        app.protocol=newprot;
        app.port=newport;
        apps.put(new Integer((newprot<<16) | newport),app);

        return new Integer(newport);
      case GET_PRV_PORT:
        parms=(Object [])paramlist;
        int theport=((Integer)parms[0]).intValue();
        int theprot=((Integer)parms[1]).intValue();
        if(apps.get(new Integer((theprot<<16)|theport)) != null) return null;
        app=new AppInfo();
        app.comp=parms[2];
        app.protocol=theprot;
        app.port=theport;
        apps.put(new Integer((theprot<<16)|theport),app);

        return new Integer(theport);
      case REMOVE_PORT:
        parms=(Object [])paramlist;
        int oldport= ((Integer)parms[0]).intValue();
        int oldprot= ((Integer)parms[1]).intValue();
        apps.remove(new Integer((oldprot<<16) | oldport));
        return null;
      case GET_IP:
        return new Integer(getMyIP());
      case GET_ALL_IP:
        java.util.List ips=new java.util.ArrayList();

        i=voports.values().iterator();
        while(i.hasNext()) {
          Port voport=(Port)i.next();
          ips.add(new Integer(voport.ip.getValue()));
        }
        return ips;
      case GET_ALL_PORT:
        java.util.List ports=new java.util.ArrayList();

        i=apps.values().iterator();
        while(i.hasNext()) {
          app=(AppInfo)i.next();
          ports.add(new Integer(app.port));
          ports.add(new Integer(app.protocol));
        }
        return ports;
      case ADD_ROUTE_ENTRY:
        parms=(Object [])paramlist;
        sw_route_table.addNewEntry(((Integer)parms[0]).intValue(),
                                    ((Integer)parms[1]).intValue(),
                                    ((Integer)parms[2]).intValue(),
                                    (SimComponent)parms[3],(String)parms[4]);
        return null;
      case CLEAR_ROUTE:
        sw_route_table.clearTable((String)paramlist);
        return null;
      case SET_PORT_IP:
        parms=(Object [])paramlist;
        Port voport=(Port)voports.get(parms[2]);
        if(voport!=null) {
          voport.ip.setValue(((Integer)parms[0]).intValue(),((Integer)parms[1]).intValue());
        }
        return null;
      case SimProvider.CI_GET_MAC:
        simparms=new java.util.ArrayList();
        i=voports.values().iterator();
        while(i.hasNext()) {
          simparms.add(new Long(((Port)i.next()).mac_addr));
        }
        return simparms;
      case GET_ALL_IP_LINK:
        parms=(Object [])paramlist;
        i=voports.values().iterator();
        while(i.hasNext()) {
          Port vport=(Port)i.next();
          if(parms[0]!=null) ((java.util.List)parms[0]).add(vport.ip);
          if(parms[1]!=null) ((java.util.List)parms[1]).add(vport.to_link);
        }
        return null;
    }
    return null;
  }
  


////////////////////////// protected methods ////////////////////////////////

  protected void sw_create() {
    voports=new java.util.HashMap();
    apps=new java.util.HashMap();

    //Initialize the parameters
    long ctick=theSim.now();
    sw_delay=new SimParamDouble("Delay to process a byte (uSec)",this,ctick,false,true,0);
    sw_speed=new SimParamInt("Switching Speed (Mbit/s)",this,ctick,false,true,1000);
    sw_oqsize=new SimParamInt("Output q_size (kbytes, -1=inf)",this,ctick,false,true,100);
    sw_red=new SimParamBool("Enable RED",this,ctick,false,true,false);
    sw_red_wq=new SimParamDouble("RED queue weight (>=0.001)",this,ctick,false,true,0.002);
    sw_red_minth=new SimParamInt("RED min q threshold (kbytes)",this,ctick,false,true,10);
    sw_red_maxth=new SimParamInt("RED max q threshold (kbytes)",this,ctick,false,true,30);
    sw_red_maxp=new SimParamDouble("RED max p (<0.1)",this,ctick,false,true,0.02);
    sw_red_s=new SimParamDouble("RED s (packet trans. time) (uSec)",this,ctick,false,true,400);
    sw_spqsize=new SimParamInt("Speedup q_size (kbytes, -1=inf)",this,ctick,false,true,100);
    sw_ai=new SimParamDouble("Averaging Interval (usec)",this,ctick,false,true,100000.0);
    sw_arp_q=new SimParamBool("Use ARP queue for IP packets",this,ctick,false,true,true);
    sw_name_seed=new SimParamBool("Use name as seed",this,ctick,false,true,true);
    sw_log_factor=new SimParamInt("Logging every (ticks) (e.g. 1, 100)",this,ctick,false,true,0);
    sw_frames_received=new SimParamInt("Frames Received",this,ctick,true,false,0);
    sw_frames_received.update(ctick);
    sw_dropped=new SimParamInt("Frames Dropped (Queue)",this,ctick,true,false,0);
    sw_dropped.update(ctick);
    sw_dropped_clas=new SimParamInt("Frames Dropped (Classifier)",this,ctick,true,false,0);
    sw_dropped_clas.update(ctick);
    sw_cpucong=new SimParamBool("CPU Slow Triggered",this,ctick,true,false,false);
    sw_cpucong.update(ctick);
    sw_tcp=new SimParamTCP("TCP",this,ctick);

    addParameter(sw_delay);
    addParameter(sw_speed);
    addParameter(sw_oqsize);
    addParameter(sw_red);
    addParameter(sw_red_wq);
    addParameter(sw_red_minth);
    addParameter(sw_red_maxth);
    addParameter(sw_red_maxp);
    addParameter(sw_red_s);
    addParameter(sw_spqsize);
    addParameter(sw_ai);
    addParameter(sw_arp_q);
    addParameter(sw_name_seed);
    addParameter(sw_log_factor);
    addParameter(sw_frames_received);
    addParameter(sw_dropped);
    addParameter(sw_dropped_clas);
    addParameter(sw_cpucong);
    addParameter(sw_tcp);
  }

  protected void sw_averaging_interval() {
    //nothing here for now...
  }

  protected void sw_proc_slot_time(SimEvent e) {
  //performing the demux_spq operation

    Port voport=(Port)e.getParams();
    EtherFrame frame;
    long ticks;

    //check for cpu congestion (just mark it, no action taken)
    if(voport.spq_size > (sw_spqsize.getValue()*1024)) {
      sw_cpucong.setValue(true);
      sw_cpucong.update(theSim.now());
    }

    //voport.spq must not be empty here!
    if(voport.spq.isEmpty()) {
      System.out.println("Warning: sw_proc_slot_time called with spq empty!!");
      return;
    }

    frame=(EtherFrame)voport.spq.remove(0);
    voport.spq_size -= (frame.length()>>3);

    if(sw_red.getValue()==true) { //whether using RED
      if(voport.outQ.isEmpty()) { //q empty
        double m=SimClock.Tick2USec(theSim.now()-voport.red_q_time) / sw_red_s.getValue();
        voport.red_avg.setValue(Math.pow(1.0-sw_red_wq.getValue(),m) * voport.red_avg.getValue(),theSim.now(),sw_log_factor.getValue());
      }
      else { //q not empty
        voport.red_avg.setValue(voport.red_avg.getValue()+sw_red_wq.getValue()*(voport.outQ_size.getValue()-voport.red_avg.getValue()),
                                 theSim.now(),sw_log_factor.getValue()); //avg=(1-wq)avg + wq(q)
      }

      boolean mark=false;
      int maxth=sw_red_maxth.getValue()<<10; //Kbyte to byte
      int minth=sw_red_minth.getValue()<<10; //Kbyte to byte
      if(voport.red_avg.getValue()>=maxth) { //avg >= maxth
        mark=true;
        voport.red_count=-1;
      }
      else if(voport.red_avg.getValue()>=minth) { //minth <= avg < maxth
        voport.red_count++;
        double pb=sw_red_maxp.getValue() * (voport.red_avg.getValue()-minth) / (maxth - minth);
        pb*= (double)frame.len / EtherFrame.MAX_ETHER_LEN;
        double pa=pb / (1 - voport.red_count*pb);
        if(randgen.nextDouble()<pa) {
          mark=true;
          voport.red_count=0;
        }
      }
      else { //avg < minth
        voport.red_count=-1;
      }

      if(mark) {
        sw_dropped.setValue(sw_dropped.getValue()+1,theSim.now(),sw_log_factor.getValue());
        frame=null;
      }
      else if((voport.outQ_size.getValue() + (frame.length()>>3) < (sw_oqsize.getValue() << 10))
        || (sw_oqsize.getValue() == -1)) {
        voport.outQ.add(frame);
        voport.outQ_size.setValue(voport.outQ_size.getValue()+(frame.length() >> 3),theSim.now(),sw_log_factor.getValue());
      }
      else {
        sw_dropped.setValue(sw_dropped.getValue()+1,theSim.now(),sw_log_factor.getValue());
        frame=null;
      }
    }
    else {
      if((voport.outQ_size.getValue() + (frame.length()>>3) < (sw_oqsize.getValue() << 10))
        || (sw_oqsize.getValue() == -1)) {
        voport.outQ.add(frame);
        voport.outQ_size.setValue(voport.outQ_size.getValue()+(frame.length() >> 3),theSim.now(),sw_log_factor.getValue());
      }
      else {
        sw_dropped.setValue(sw_dropped.getValue()+1,theSim.now(),sw_log_factor.getValue());
        frame=null;
      }
    }

  //output frame to link if possible
    if(!voport.outQ.isEmpty() && !voport.link_busy) {
      voport.link_busy=true;
      sw_schedule_output(voport);
    }

  //schedule next proc_slot if needed
    if(!voport.spq.isEmpty()) {
      frame=(EtherFrame)voport.spq.get(0);
      ticks=SimClock.USec2Tick(frame.length() / (double)sw_speed.getValue());
      theSim.enqueue(new SimEvent(MY_SLOT_TIME,this,this,theSim.now()+ticks,voport));
    }
  }

  protected void sw_ready(SimEvent e) {
    Port voport=(Port)voports.get(e.getSource());
    if(voport!=null) {
      if(voport.link_busy) {
        voport.link_busy=false;
        if(!voport.outQ.isEmpty()) {
          voport.link_busy=true;
          sw_schedule_output(voport);
        }
      }
    }
  }

  protected void sw_schedule_output(Port voport) {
    EtherFrame frame=(EtherFrame)voport.outQ.remove(0);
    voport.outQ_size.setValue(voport.outQ_size.getValue()-(frame.length()>>3),theSim.now(),sw_log_factor.getValue());

    theSim.enqueue(new SimEvent(SimProvider.EV_RECEIVE,this,
                                voport.to_link,theSim.now(),frame));

    //RED variable
    if(voport.outQ.isEmpty()) voport.red_q_time=theSim.now();

    //inform analyzer
    if(analyzer!=null) analyzer.update(frame,this,voport.to_link);
  }

  protected void sw_send_spq(EtherFrame frame,Port voport) {
    voport.spq.add(frame);