/Users/yzchen/ns/ns-allinone-2.33/ns-2.33/tcp/formula.h

#define MAXRATE 25000000.0 
#define SAMLLFLOAT 0.0000001

/*
 * This takes as input the packet drop rate, and outputs the sending 
 *   rate in bytes per second.
 */
static double p_to_b(double p, double rtt, double tzero, int psize, int bval) 
{
        double tmp1, tmp2, res;

        if (p < 0 || rtt < 0) {
                return MAXRATE ; 
        }
        res=rtt*sqrt(2*bval*p/3);
        tmp1=3*sqrt(3*bval*p/8);
        if (tmp1>1.0) tmp1=1.0;
        tmp2=tzero*p*(1+32*p*p);
        res+=tmp1*tmp2;
//      if (formula_ == 1 && p > 0.25) { 
//              // Get closer to RFC 3714, Table 1.
//              // This is for TCP-friendliness with a TCP flow without ECN
//              //   and without timestamps.
//              // Just for experimental purposes. 
//              if p > 0.70) {
//                      res=res*18.0;
//              } else if p > 0.60) {
//                      res=res*7.0;
//              } else if p > 0.50) {
//                      res=res*5.0;
//              } else if p > 0.45) {
//                      res=res*4.0;
//              } else if p > 0.40) {
//                      res=res*3.0;
//              } else if p > 0.25) {
//                      res=res*2.0;
//              }
//      }
        // At this point, 1/res gives the sending rate in pps:
        // 1/(rtt*sqrt(2*bval*p/3) + 3*sqrt(3*bval*p/8)*tzero*p*(1+32*p*p))
        if (res < SAMLLFLOAT) {
                res=MAXRATE;
        } else {
                // change from 1/pps to Bps.
                res=psize/res;
        }
        if (res > MAXRATE) {
                res = MAXRATE ; 
        }
        return res;
}