udp.cc

linux平台下,在ns2里面实现的基于价格的分布式优化算法源代码

/* -*-	Mode:C++; c-basic-offset:8; tab-width:8; indent-tabs-mode:t -*- */
/*
 * Copyright (C) Xerox Corporation 1997. All rights reserved.
 *  
 * License is granted to copy, to use, and to make and to use derivative
 * works for research and evaluation purposes, provided that Xerox is
 * acknowledged in all documentation pertaining to any such copy or derivative
 * work. Xerox grants no other licenses expressed or implied. The Xerox trade
 * name should not be used in any advertising without its written permission.
 *  
 * XEROX CORPORATION MAKES NO REPRESENTATIONS CONCERNING EITHER THE
 * MERCHANTABILITY OF THIS SOFTWARE OR THE SUITABILITY OF THIS SOFTWARE
 * FOR ANY PARTICULAR PURPOSE.  The software is provided "as is" without
 * express or implied warranty of any kind.
 *  
 * These notices must be retained in any copies of any part of this software.
 */

#ifndef lint
static const char rcsid[] =
    "@(#) $Header: /nfs/jade/vint/CVSROOT/ns-2/apps/udp.cc,v 1.19 2001/11/16 22:29:59 buchheim Exp $ (Xerox)";
#endif

#include "udp.h"
#include "rtp.h"
#include "random.h"
#include "address.h"
#include "ip.h"
#include "mac/mac-802_11.h"
    
//Yuan add
#define CAPACITY 800 //1000K
//#define EPSILON  0.00001
//#define BETA	0
#define STEP  5    
    
static class UdpAgentClass : public TclClass {
public:
	UdpAgentClass() : TclClass("Agent/UDP") {}
	TclObject* create(int, const char*const*) {
		return (new UdpAgent());
	}
} class_udp_agent;

UdpAgent::UdpAgent() : Agent(PT_UDP), seqno_(-1),fseqno_(-1), timer_(this),  first_time(1)
{
	bind("packetSize_", &size_);
	bind("myfid_", &myfid_);
    bind("EPSILON", &EPSILON);
    bind("BETA",&BETA);
    rate_ = 50; //init rate 200K
    price_ = 0;
}

UdpAgent::UdpAgent(packet_t type) : Agent(type), timer_(this), first_time(1)
{
	bind("packetSize_", &size_);
	bind("myfid_", &myfid_);
    bind("EPSILON", &EPSILON);
    bind("BETA",&BETA);
    rate_ = 50; //init rate 200K
    price_ = 0;
}

int hdr_pdp::offset_;

static class PDPHeaderClass : public PacketHeaderClass {
public:
        PDPHeaderClass() : PacketHeaderClass("PacketHeader/PDP",
                                                 sizeof(hdr_pdp)) {
        bind_offset(&hdr_pdp::offset_);
    }
} class_pdphdr;

//Yuan add
void UdpAgent::sendbackmsg(double price)
{
        Packet *p;
	    double local_time = Scheduler::instance().clock();
        p = allocpkt();
        
        struct hdr_cmn *ch = HDR_CMN(p);
        hdr_pdp* ph = hdr_pdp::access(p);
        
		//ch->size() = size_;
		ch->size() = 10;
        ph->rate() = -1;
        ph->price() = price;
        ph->flag() = 0;
		ch->timestamp() = 
		    (u_int32_t)(SAMPLERATE*local_time);
        ch->ptype() = PT_FEEDBACK;
        fseqno_++;
        ch->uid_ = fseqno_;
		p->setdata(NULL);
		target_->recv(p);
}

// put in timestamp and sequence number, even though UDP doesn't usually 
// have one.
void UdpAgent::sendmsg(int nbytes, AppData* data, const char* flags)
{

	double local_time = Scheduler::instance().clock();
	Packet *p;

    if (first_time){
        char filename[10];
        sprintf(filename, "x%d.dat", myfid_);
        fd_x = fopen(filename, "w");
        first_time = 0;
    }

    //Yuan change
		p = allocpkt();
        struct hdr_cmn *ch = HDR_CMN(p);
        struct hdr_ip *ih = HDR_IP(p);
        hdr_pdp* ph = hdr_pdp::access(p);

	    ch->size() = size_;
        ih->flowid() = myfid_;
        
        ph->rate() = rate_;
        
        fprintf(fd_x,"%f %f\n",local_time,rate_);
        
        ph->price() = 0;
        ph->flag() = 1;
		ch->timestamp() = (u_int32_t)(SAMPLERATE*local_time);
        ch->ptype() = PT_CBR;
		ch->prev_hop_ = LARGE_INT8; //define something
        seqno_++;
        ch->uid_ = seqno_;
		p->setdata(data);
		target_->recv(p);
        nextPkttime_ = next_interval();
	
        /* schedule it */
	    if (nextPkttime_ > 0)
		    timer_.resched(nextPkttime_);
	    else{
            printf("Error: nextPkettime_ <= 0 \n");
            return;
        }

	//idle();
}
void UdpAgent::recv(Packet* pkt, Handler*)
{
    struct hdr_cmn *ch = HDR_CMN(pkt);
    hdr_pdp* ph = hdr_pdp::access(pkt);
    if ((ch->ptype() == PT_CBR)&&(ph->flag())) {
        printf("F%d recv DATA price: %f, rate %f\n", myfid_, ph->price_, ph->rate());
        if (fabs(ph->price() - price_)>EPSILON){
//            printf("** F%d recv DATA price: %f, rate %f\n", myfid_, ph->price_, ph->rate());
            sendbackmsg(ph->price());
            price_ = ph->price();
        }
    }

    if (ch->ptype()== PT_FEEDBACK) {
//        printf("F%d udp recv feedback messge: seq %d price %f\n", myfid_, ch->uid_, ph->price());
        if (fseqno_ < ch->uid_) {
           printf("** F%d udp recv feedback messge: seq %d price %f\n", myfid_, ch->uid_, ph->price());
            fseqno_ = ch->uid_;
            rate_ = cal_rate(ph->price());
        }
    }
        
	Packet::free(pkt);
}
/*
 * Yuan add
 * calculate the rate based on path-aggregated price
 * assume U = log x
 */

double UdpAgent::cal_rate(double new_price)
{
    double new_rate;
//Yuan new change
	if (price_ == 0)
		price_ = new_price;
	else
		price_ = BETA*price_ + (1-BETA)*new_price;
    new_rate = 1/price_; //the unit is Kbps
//    new_rate = rate_ + STEP*(1-rate_*price_);

    if (new_rate <0) new_rate = 0;
    if (new_rate >CAPACITY) new_rate = CAPACITY;

    printf("F%d udp::cal_rate: price: %f, rate: %f\n",myfid_,new_price,new_rate);
    return new_rate;
}

int UdpAgent::command(int argc, const char*const* argv)
{
	if (argc == 4) {
		if (strcmp(argv[1], "send") == 0) {
            PacketData* data = new PacketData(1 + strlen(argv[3]));
			strcpy((char*)data->data(), argv[3]);
			sendmsg(atoi(argv[2]), data);
			return (TCL_OK);
		}
	} else if (argc == 5) {
		if (strcmp(argv[1], "sendmsg") == 0) {
			PacketData* data = new PacketData(1 + strlen(argv[3]));
			strcpy((char*)data->data(), argv[3]);
			sendmsg(atoi(argv[2]), data, argv[4]);
			return (TCL_OK);
		}
	}
	return (Agent::command(argc, argv));
}


void UdpAgent::timeout()
{
	/* send a packet */
    sendmsg(size_); //send a pkt (nbyte_ = size_)
}

double UdpAgent::next_interval()
{
	// Recompute interval in case rate_ or size_ has changes
    // Yuan Note fix rate_ temporally
	//double t = (double)(size_ << 3)/(double)(rate_*1000000);
	double t = (double)(size_ << 3)/(double)(rate_*1000); //the unit is Kbps
    return(t);
}

void UdpTrafficTimer::expire(Event *)
{
	udpagent_->timeout();
}