/* -*-	Mode:C++; c-basic-offset:8; tab-width:8; indent-tabs-mode:t -*- *//* * Copyright (c) 1996-1997 The Regents of the University of California. * All rights reserved. *  * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright *    notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright *    notice, this list of conditions and the following disclaimer in the *    documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software *    must display the following acknowledgement: * 	This product includes software developed by the Daedalus  *      Research Group at the University of California, Berkeley. * 4. Neither the name of the University nor of the Research Group may be used *    to endorse or promote products derived from this software without *    specific prior written permission. *  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * ack-recons.cc: contributed by the Daedalus Research Group,  * UC Berkeley (http://daedalus.cs.berkeley.edu). * * $Header: /nfs/jade/vint/CVSROOT/ns-2/tcp/ack-recons.h,v 1.4 2000/09/01 03:04:05 haoboy Exp $ *//* * TCP Ack reconstructor.  This object sits on the other end of a constrained  * link and intersperses TCP acks to the source (without violating the e2e  * semantics of TCP acks).  This allows us to get good performance for TCP  * over various asymmetric networks, in conjunction with techniques to reduce  * the frequency of acks (such as ack filtering) with making any changes to  * the TCP source (e.g., like those implemented in tcp-asym.cc).   */#ifndef ns_ack_recons_h#define ns_ack_recons_h#include "semantic-packetqueue.h"class AckReconsController : public TclObject {public:	AckReconsController() : spq_(0) {}	void recv(Packet *p, Handler *h=0);	SemanticPacketQueue *spq_;};	class AckRecons : public Agent {public:	AckRecons(nsaddr_t src, nsaddr_t dst) :		Agent(PT_TCP), spq_(0), src_(src), dst_(dst),		ackTemplate_(0), ackPending_(0), lastAck_(0), 		lastRealAck_(0) {			bind("lastTime_", &lastTime_);			bind("lastAck_", &lastAck_);			bind("lastRealTime_", &lastRealTime_);			bind("lastRealAck_", &lastRealAck_);			bind("ackInterArr_", &ackInterArr_);			bind("ackSpacing_", &ackSpacing_);			bind("deltaAckThresh_", &deltaAckThresh_);			bind("delack_", &delack_);			bind("adaptive_", &adaptive_);			bind("alpha_", &alpha_);			bind("size_", &size_);		}	int command(int argc, const char*const* argv);	void handle(Event *e);	void recv(Packet *p);	SemanticPacketQueue *spq_; /* the corresponding queue of packets */private:	void sendack(int ack, double t); /* send ack pkt at time t */	nsaddr_t src_;		/* src addr:port */	nsaddr_t dst_;		/* dst addr:port */	Packet	*ackTemplate_;	/* used as a template for generated acks */	int	ackPending_;	int	lastAck_;	/* last ack sent by recons, maybe generated */	int	lastRealAck_;	/* last ack actually received on link */	double	lastTime_;	/* time when last ack was sent */	double	lastRealTime_;	/* time when last ack arrived on link */	int	dupacks_;	/* number of dup acks seen so far */	int	size_;		/* TCP packet size -- needed because TCP				 * acks are in terms of packets */	/* knobs/policies */	int	deltaAckThresh_; /* threshold for reconstruction to kick in */	double	ackInterArr_;	/* estimate of arrival rate of acks */	double	ackSpacing_;	/* time duration between acks sent by recons */	int	delack_;	/* generate ack at least every delack_ acks */	int	adaptive_;	/* whether to adapt ack bandwidth? */	double	alpha_;	/* used in linear filter for ack rate est. */};#endif