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Thuật toán tăng giảm

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Thuật toán tăng giảm

Phụ lục PHẦN PHỤ LỤC Thuật toán tăng giảmTăng cộng giảm nhân AIMD #define_param a range 0.1 to 1 default 0.1 #define_param b range 0.1 to 0.9 default 0.5 maxrate = 1.0; if(traffic > 1){ rate = rate * b; } else{ rate = rate + a; rate = min(rate, maxrate); } • Tăng cộng giảm cộng AIAD #define_param a range 0.1 to 0.9 default 0.2 #define_param b range 0.1 to 0.9 default 0.3 maxrate = 1.0; minrate = 0.0; if(traffic > 1){ rate = rate - b; rate = max(rate, minrate); } else{ rate = rate + a; rate = min(rate, maxrate); } • Tăng nhân giảm cộng MIAD #define_param a range 1 to 2 default 1.2 #define_param b range 0.1 to 0.9 default 0.5 maxrate = 1.0; minrate = 0.0; if(traffic > 1){ rate = rate - b; rate = max(rate, minrate); } else{ rate = rate * a; rate = min(rate, maxrate); } Phụ lục • Tăng nhân giảm nhân MIMD #define_param a range 1 to 2.0 default 1.2 #define_param b range 0.1 to 0.9 default 0.5 maxrate = 1.0; if(traffic > 1){ rate = rate * b; } else{ rate = rate * a; rate = min(rate, maxrate); } Kịch bản xây dựng trong ns2 #--------- So do ket noi mang ----------------------------------------------# # n0 # \ Bottleneck Dich # n1--R0-----------------------R1 # / # n2 # # Cac luong xcp va tcp dung chung router xcp Queue/XCP set tcp_xcp_on_ 1 Agent/TCP set minrto_ 1 # Tao doi tuong mo phong set ns [new Simulator] $ns use-scheduler Heap # Tao file trace set f_all [open out.tr w] $ns trace-all $f_all #----------------------------------------------------------------------------- # Dinh nghia cac ham su dung trong chuong trinh chinh #----------------------------------------------------------------------------- # Tao tham so cho hang RED proc set-red-params { qsize } { Queue/RED set thresh_ [expr 0.6 * $qsize] Queue/RED set maxthresh_ [expr 0.8 * $qsize] Phụ lục Queue/RED set q_weight_ 0.001 Queue/RED set linterm_ 10 Queue/RED set bytes_ false ; Queue/RED set queue_in_bytes_ false ; Agent/TCP set old_ecn_ true Queue/RED set setbit_ true } #---------------------------------------------------------------------------- # Tao topo mang proc create-topology2 { BW delay qtype qsize numSideLinks deltaDelay } { global ns # Thiet lap kich co hang den kich co duong truyen # Gia su rang kich co goi la 1000Bytes if { $qsize == 0 } { set qsize [expr round([expr ($BW / 8) * 2 * $delay])] } #Khai bao 2 nut R0 R1 set i 0 while { $i < 2 } { global R$i set R$i [$ns node] incr i } $R0 color red $R1 color blue $R0 label "That co chai" $R1 label "Dich" # Khai bao link: nodes bw delay queue $ns duplex-link $R0 $R1 [set BW]Mb [set delay]ms $qtype $ns queue-limit $R0 $R1 $qsize $ns queue-limit $R1 $R0 $qsize # Xu li hang bi that co chai, cho phep thiet lap cac tham so RED global Bottleneck rBottleneck set Bottleneck [[$ns link $R0 $R1] queue] set rBottleneck [[$ns link $R1 $R0] queue] global l rl set l [$ns link $R0 $R1] set rl [$ns link $R1 $R0] global all_links set all_links "$l $rl " Phụ lục # Duong truyen nha'nh co cung bang thong nhu duong that co chai set i 0 while { $i < $numSideLinks } { global n$i q$i rq$i l$i rl$i set n$i [$ns node] $ns duplex-link [set n$i] $R0 [set BW]Mb [expr $delay + $i* $deltaDelay]ms $qtype $ns queue-limit [set n$i] $R0 $qsize $ns queue-limit $R0 [set n$i] $qsize set q$i [[$ns link [set n$i] $R0] queue] set rq$i [[$ns link $R0 [set n$i]] queue] set l$i [$ns link [set n$i] $R0] set rl$i [$ns link $R0 [set n$i]] set all_links "$all_links [set l$i] [set rl$i]" incr i } } #------------------------------------------------------------------------------------------ #------Lop GeneralSender: can thiet cho phia goi ftp------------------------------ Class GeneralSender -superclass Agent GeneralSender instproc init { id node rcvrTCP otherparams } { global ns $self next $self instvar tcp_ id_ ftp_ node_ tcp_rcvr_ tcp_type_ set id_ $id set node_ $node if { [llength $otherparams] > 1 } { set TCP [lindex $otherparams 1] } else { set TCP "TCP/Reno" } set tcp_type_ $TCP set tcp_ [new Agent/$TCP] $tcp_ set packetSize_ 1000 $tcp_ set class_ $id set ftp_ [new Source/FTP] $ftp_ set agent_ $tcp_ $ns attach-agent $node $tcp_ $ns connect $tcp_ $rcvrTCP set tcp_rcvr_ $rcvrTCP Phụ lục set startTime [lindex $otherparams 0] $ns at $startTime "$ftp_ start" puts " Khoi tao phia goi $id_ tai thoi gian t= $startTime s" } GeneralSender instproc trace-xcp parameters { $self instvar tcp_ id_ tcpTrace_ global ftracetcp$id_ ns set ftracetcp$id_ [open xcp$id_.tr w] set tcpTrace_ [set ftracetcp$id_] $tcp_ attach-trace [set ftracetcp$id_] if { -1 < [lsearch $parameters cwnd] } { $tcp_ tracevar cwnd_ } } #----------------------------------------------------------------------------------------- #------------------------Thuc hien chuc nang ve do thi----------------------# # do thi bien trace xcp proc plot-xcp { TraceName nXCPs PlotTime what } { exec rm -f xgraph_cwnd.tcp set f [open xgraph_cwnd.tcp w] set a cwnd puts $f "TitleText: $TraceName" puts $f "Device: Postscript" foreach i $nXCPs { # trace TCP duoc flushed khi cac nguon ngung exec rm -f temp.tcp exec touch temp.tcp global ftracetcp$i if [info exists ftracetcp$i] { flush [set ftracetcp$i] } set result [exec awk -v PlotTime=$PlotTime -v what=$what { { if (( $6 == what ) && ($1 > PlotTime)) { print $1, $7 >> "temp.tcp"; } } } xcp$i.tr] puts $f \"$what$i exec cat temp.tcp >@ $f Phụ lục puts $f "\n" flush $f } close $f exec xgraph -P -bg white -fg black -zg black -x "Thoi gian (s)" -y "cwnd (KBytes)" xgraph_$a.tcp & return } #------------------------------------------------------------------------------------ proc plot-xcp-queue { PlotTime traceFile } { exec rm -f xcp_queue exec rm -f temp.q temp.a temp.p temp.avg_enqueued temp.avg_dequeued temp.x temp.y exec touch temp.q temp.a temp.p temp.avg_enqueued temp.avg_dequeued temp.x temp.y exec awk -v PT=$PlotTime { { if (($1 == "q" && NF>2) && ($2 > PT)) { print $2, $3 >> "temp.q" } else if (($1 == "a" && NF>2) && ($2 > PT)) { print $2, $3 >> "temp.a" } else if (($1 == "p" && NF>2) && ($2 > PT)) { print $2, $3 >> "temp.p" } } } $traceFile set ff [open xcp_queue w] puts $ff "TitleText: Trang thai hang DROPTAIL XCP" puts $ff "Device: Postscript \n" puts $ff \"queue exec cat temp.q >@ $ff puts $ff \n\"ave_queue exec cat temp.a >@ $ff puts $ff \n\"prob_drop exec cat temp.p >@ $ff close $ff exec xgraph -P -bg white -fg black -zg black -x "Thoi gian (s)" -y "Queue (goi)" xcp_queue & Phụ lục } #------------------------------------------------------------------------------------- proc plot-red-queue { PlotTime traceFile } { exec rm -f red_queue exec rm -f temp.q temp.a temp.p temp.avg_enqueued temp.avg_dequeued temp.x temp.y exec touch temp.q temp.a temp.p temp.avg_enqueued temp.avg_dequeued temp.x temp.y exec awk -v PT=$PlotTime { { if (($1 == "Q" && NF>2) && ($2 > PT)) { print $2, $3 >> "temp.q" } else if (($1 == "a" && NF>2) && ($2 > PT)) { print $2, $3 >> "temp.a" } else if (($1 == "p" && NF>2) && ($2 > PT)) { print $2, $3 >> "temp.p" } } } $traceFile set ff [open red_queue w] puts $ff "TitleText: Trang thai hang RED TCP" puts $ff "Device: Postscript \n" puts $ff \"queue exec cat temp.q >@ $ff puts $ff \n\"ave_queue exec cat temp.a >@ $ff puts $ff \n\"prob_drop exec cat temp.p >@ $ff close $ff exec xgraph -P -bg white -fg black -zg black -x "Thoi gian (s)" -y "Queue (goi)" red_queue & } #--------------------------------------------------------------------------------------- proc plot-red {varname filename PlotTime} { exec rm -f $filename exec touch $filename set result [exec awk -v PlotTime=$PlotTime -v what=$varname -v file=$filename { { Phụ lục if (( $1 == what ) && ($2 > PlotTime)) { print $2, $3 >> file ; } } } ft_red_Bottleneck.tr] exec xgraph -P -bg white -fg black -zg black -x "Thoi gian (s)" -y "Hieu qua su dung" -t "Hieu qua su dung router XCP khi co 1 luong TCP" $filename } #-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*- MO PHONG -*-*-*-*-*-*-*-*--*-*-*-*-* set seed 472904 set qType XCP set BW 20; # Mb/s set nXCPs 3; # so luong set delay 10; # ms set rtg [new RNG] $rtg seed $seed # thiet lap bo dem den kich co duong dan set qSize [expr round([expr ($BW / 8.0) * 4 * $delay * 1.0])]; puts "\n CAC THONG SO MO PHONG\n" puts " Bang thong = $BW Mb/s\n" puts " Do tre = $delay ms\n" puts " Kich co hang = $qSize KBytes\n" set tracedXCPs "0 1 2 3 " set SimStopTime 30 set PlotTime 0 #------------------------------Khoi tao mo phong----------------------------------# # Goi ham tao topo set-red-params $qSize create-topology2 $BW $delay $qType $qSize $nXCPs 0.0 foreach link $all_links { set queue [$link queue] switch $qType { "XCP" { $queue set-link-capacity [[$link set link_] set bandwidth_]; } "DropTail/XCP" { Phụ lục $queue set-link-capacity-Kbytes [expr [[$link set link_] set bandwidth_] / 8000]; } default { puts "Incorrect qType $qType" exit 0 } } } # Tao cac nguon: # Tao 3 nguon XCP set i 0 while { $i < $nXCPs } { set StartTime [expr [$rtg integer 1000] * 0.001 * (0.01 * $delay) + $i * 0.0] set rcvr_XCP [new Agent/TCPSink/XCPSink] $ns attach-agent $R1 $rcvr_XCP set src$i [new GeneralSender $i [set n$i] $rcvr_XCP "$StartTime TCP/Reno/XCP"] [[set src$i] set tcp_] set packetSize_ 1000 [[set src$i] set tcp_] set window_ [expr $qSize * 10] $ns color $i Blue incr i } # Tao 1 nguon TCP tu node 0 set StartTime 0.0900000000000000023 set rcvr_TCP [new Agent/TCPSink] $ns attach-agent $R1 $rcvr_TCP set src$i [new GeneralSender $i $n0 $rcvr_TCP "$StartTime TCP/Reno"] [[set src$i] set tcp_] set packetSize_ [expr 100 * ($i +10)] # don vi Byte [[set src$i] set tcp_] set window_ [expr $qSize * 10] # KByte $ns color $i Red incr i #------------------------------------- Trace --------------------------------------------# set i 0 # Trace cac nguon foreach i $tracedXCPs { [set src$i] trace-xcp "cwnd" } # Trace cac hang Phụ lục foreach queue_name "Bottleneck rBottleneck" { set queue [set "$queue_name"] switch $qType { "XCP" { global "ft_red_$queue_name" global "tcp_$queue_name" set "ft_red_$queue_name" [open ft_red_[set queue_name].tr w] $queue attach [set ft_red_$queue_name] set "tcp_$queue_name" [open tcp.tr w] set tcpq [$queue set vq_(1)] $tcpq attach [set tcp_$queue_name] $tcpq trace curq_ $tcpq trace ave_ $tcpq trace prob1_ } "DropTail/XCP" {} } } #------------------------ Chay mo phong----------------------------------# proc flush-files {} { set files "f_all ft_red_Bottleneck ft_red_rBottleneck" global tracedXCPs foreach file $files { global $file if {[info exists $file]} { flush [set $file] close [set $file] } } foreach i $tracedXCPs { global src$i set file [set src$i tcpTrace_] if {[info exists $file]} { flush [set $file] close [set $file] } } } proc finish {} { global ns if {[info exists f]} { . Phụ lục PHẦN PHỤ LỤC Thuật toán tăng giảm • Tăng cộng giảm nhân AIMD #define_param a range 0.1 to 1 default 0.1. rate = rate * b; } else{ rate = rate + a; rate = min(rate, maxrate); } • Tăng cộng giảm cộng AIAD #define_param a range 0.1 to 0.9 default 0.2 #define_param

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