readme

ns2中没有的关于BLUE和SFB的仿真源码。

By

Sunil Thulasidasan
RADIANT Group <http://www.lanl.gov/radiant/>
Los Alamos National Laboratory
[e-mail]

Contents of this file
---------------------
0.) Change Log
1.) BLUE, Stochastic Fair BLUE (SFB) brief
2.) NS Version Details
3.) Details of changes to NS
4.) Setup instructions
5.) Integrating into NS distribution
6.) NS documentation for BLUE, SFB and guidelines


0. Change Log
   ----------
Changes to earlier implementation

	(i)   ECN support added for BLUE
	(ii)  ECN support added for Stochastic Fair Blue (SFB)
	(iii) ip.h (packet header) extended to add marker for identifying rogue flows.
	(iii) A very minor bug in the dequeue function in SFB has been corrected.
	     


1. BLUE, Stochastic Fair BLUE brief
   --------------------------------
BLUE is a  congestion avoidance algorithm , developed by W. Feng et al,  that uses packet loss and link utilisation behaviour
for active queue management. The paper on BLUE can be found at http://www.eecs.umich.edu/~wuchang/work/CSE-TR-387-99.pdf

Stochastic Fair BLUE (SFB), also by Feng et al, is an extension of BLUE, which uses Bloom filters to enforce fairness among
flows. The paper on SFB can be found at http://www.thefengs.com/wuchang/blue/41_2.PDF


2.) Version Details
    ---------------
BLUE and Stochastic Fair BlUE , originally implemeneted for ns-1.1 by Feng, has been ported to  the most recent 
release of NS - ns2.1b8 (as of 11/2001).
The C++/TCL code and documentation can be found at http://home.lanl.gov/sunil/ns/ns-blue.tar.gz


3.) Details of changes to NS
    ------------------------

The following files have been *added* to the C++ directory
<blue.h,blue.cc> for BLUE
<fairblue.h,fairblue.cc> for SFB

The following file has been modiefied in the C++ directory (common directory
in the latest ns distribution)
<ip.h>

The following files have been modified in the tcl/lib directory
ns-default.tcl 
ns-lib.tcl
(Refer section 5 on the oTcl changes)


4.) Setup instructions
    ------------------
  a.)  Copy the following files into the c++ directory
 	blue.h
	blue.cc
	fairblue.h
	fairblue.cc
	ip.h

  b.)  Copy the fillowing files into the tcl/lib directory
	ns-default.tcl
	ns-lib.tcl
   (If you do not wish to over write your current ns tcl files, refer section 5.)


  c.)  Copy the following files into your test directory
        test-blue.tcl
        test-sfb.tcl 	
	
  d.)  Add the following line to the Makefile in the "OBJ_CC = " section
	blue.o fairblue.o
	
  e.)  For compiling, type "make" at the command prompt. If dependency 
       errors show up (unlikely), try the following

	make clean
	make depend
	make  	


5.) Integrating into the NS distribution
    ------------------------------------
    The BLUE and SFB code can be integrated into the distributions fairly easily.	
    Copy the following files into the c++ directory
 	blue.h
	blue.cc
	fairblue.h
	fairblue.cc
	
	Add the following lines in ip.h (inside the struct hdr_ip declaration)
	    int             pmark_; //Marker for unresponsive flows - used
	    		    	    //by Fairness algos like Fair Blue
	
	Add the following lines in ip.h where the member access functions are defined
	     int& pmark() { return (pmark_);


	Add the following lines to ns-default.tcl
		 
		Queue/Blue set drop_front_ false
		Queue/Blue set bytes 0
		Queue/Blue set setbit true ;#ECN support turned on by default
		Queue/Blue set decrement 0.00025
		Queue/Blue set increment 0.0025
		Queue/Blue set dhold-time 100ms
		Queue/Blue set ihold-time 100ms
		Queue/Blue set dalgorithm 0
		Queue/Blue set ialgorithm 0
		Queue/Blue set pmark 1
		Queue/Blue set pktsize 1000 


		#For SFB (Stochastic Fair Blue)
		Queue/SFB set drop_front_ false
		Queue/SFB set bytes 0
		Queue/SFB set setbit true ;#ECN support turned on by default
		Queue/SFB set decrement 0.001
		Queue/SFB set increment 0.005
		Queue/SFB set hold-time 100ms
		Queue/SFB set algorithm 0
		Queue/SFB set pbox-time 50ms
		Queue/SFB set pktsize 1000
		Queue/SFB set hinterval 20s ;#hash interval switching duration

	
	Add the following lines into ns-lib.tcl in the simple-link{} procedure (look for Simulator instproc simple-link{...} )

	#For Blue 
	if {$qtype == "Blue"} {	
		$q link [$link_($sid:$did) set link_]
	}

	#For SFB 
	if {$qtype == "SFB"} {
	 	$q link [$link_($sid:$did) set link_]
	}


	Add changes to makefile (refer section 4)

	Copy test-blue.tcl, test-sfb.tcl (these are the test scripts) into tcl/test


6.) NS documentation
    ----------------
  
    BLUE objects are a subclass of Queue objects that implement the BLUE queueing algorithm. This queue object uses a single
    FIFO queue to enqueue and dequeue packets. There are no methods that are specific to BLUE. Configuration parameters are :

	drop_front_  /*boolean, indicates whether to drop tail or drop front on queue overflow. Set to 'false' by default. */                    
        setbit       /*values are true (default) or false, indicates whether to mark ECN bit*/
        decrement    /*marking/dropping probability (pm) decrement value*/
        increment    /*pm increment value*/
        dhold-time   /*time interval during which pm cannot be decreased*/
	ihold-time   /*time interval during which pm cannot be increased*/

	/*the hold-times are to give enough time for the previous changes to pm
	/*to take effect*/
  
        pmark 	     /*inital value for pm*/
        pktsize      /*packet size*/ 		 
    		

    SFB objects are a subclass of Queue objects that implement the SFB algorithm. The Queue object uses a single FIFO queue 
    to enqueue and dequeue packets, while a bloom filter is used for accounting flow statistics. There are no methods that are
    specific to SFB. Configuration parameters are 		

	drop_front_  /*boolean, indicates whether to drop tail or drop front on queue overflow. Set to 'false' by default. */
	setbit       /*values are true (default) or false, indicates whether to mark ECN bit*/	
        decrement    /*marking/dropping  probability (pm) decrement value*/
        increment    /*pm increment value*/
        hold-time    /*time interval for which pm cannot be changed*/
        pbox-time    /*time interval during which packets from unresponsive flows cannot be queued*/
        pktsize     /*packet size*/
        hinterval   /*hash function perturbation time interval*/


	Guidelines for setting SFB Parameters
	-------------------------------------
	pbox-time : This determines the bandwidth allocated to rogue flows
	(rate limiting bandwidth). Preconfigured value is 0.16Mbps. For a
	different b/w, change this value in either
	ns-default.tcl or your your test script.(see test-sfb.tcl on how to do this)
	
	hinterval : This is the hash interval perturbation interval. Try not
	to set this to too low (i.e, much less than the time taken to drain the
	queue), or too high a value. Should be set to some multiple of
	queue-draining-time.


/*DISCLAIMER*/
--------------
THIS SOFTWARE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES,
INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 
FOR A PARTICULAR PURPOSE.


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