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#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;
}
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