scoreboard-rh.h

Ns2 TCP 协议改进 版本 提高goodput

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 * @(#) $Header: /nfs/jade/vint/CVSROOT/ns-2/tcp/scoreboard-rh.h,v 1.2 2000/08/12 21:46:10 sfloyd Exp $
 */

#ifndef ns_scoreboard_h
#define ns_scoreboard_h

//  Definition of the scoreboard class:

#define SBSIZE 1024

#include "tcp.h"

class ScoreBoardRH {
  public:
        ScoreBoardRH(int *numdupacks) : numdupacks_(numdupacks) {first_=0; length_=0; retran_occured_=0;}
	int IsEmpty () {return (length_ == 0);}
	void ClearScoreBoard (); 
	int GetNextRetran ();
	void MarkRetran (int retran_seqno, int snd_nxt, int rh_id);
	int UpdateScoreBoard (int last_ack_, hdr_tcp*, int rh_id);
	int CheckSndNxt (int sack_max);
	int GetFack (int last_ack);
	int GetNewHoles ();
	void TimeoutScoreBoard (int snd_nxt);
	int FakeSack (int last_ack, int num_dupacks);
	int RetranSacked (int rh_id);
	int RetranOccurred (int rh_id) {return (retran_occured_ == rh_id);}
	
  protected:
	int first_, length_;
	int retran_occured_;             /* This variable stores the last adjustment interval
					    in which a retransmission occured  */
	int retran_sacked_;              /* This variable stores the last adjustment interval
					    in which a retransmission was sacked  */
        int *numdupacks_;		 /* I know, it stinks...  But this is numdupacks_ from
					  * our parent TCP stack. */
   
	struct ScoreBoardNode {
		int seq_no_;		/* Packet number */
		int ack_flag_;		/* Acked by cumulative ACK */
		int sack_flag_;		/* Acked by SACK block */
		int retran_;		/* Packet retransmitted */
		int snd_nxt_;		/* snd_nxt at time of retransmission */
		int sack_cnt_;		/* number of reports for this hole */
		int rh_id_;             /* The id of the rate-halving adjustment interval */
	} SBN[SBSIZE+1];
};

#endif