Feng Gang National Laboratory of Communication,UESTC Aug 2017 Ver 1.4 Outline An overview on Internet applications and QoS requirements Internet architecture and Protocols Internet traffic control and Congestion Control Traffic policing and shaping buffer management(e.g.tail drop,AQM:RED,Blue....) Packet scheduling (e.g.WFQ,DRR,etc.). TCP.ECN,etc. Standardized services Intserv/RSVP,DiffServ 2616009:Network Traffic Engineering 1:Overview Page.16
2616009: Network Traffic Engineering Feng Gang National Laboratory of Communication, UESTC Aug 2017 Ver 1.4 1: Overview Page.16 Outline • An overview on Internet applications and QoS requirements • Internet architecture and Protocols • Internet traffic control and Congestion Control - Traffic policing and shaping - buffer management (e.g. tail drop, AQM: RED, Blue,…) - Packet scheduling (e.g. WFQ, DRR, etc.). - TCP, ECN, etc. • Standardized services - Intserv/RSVP, DiffServ
Feng Gang National Laboratory of Communication,UESTC Aug 2017 Ver 1.4 An Analogue to Traffic Control: Transportation Traffic Management Signaling and Admission control 2) haping 3 Policing ©Scheduling⑤ Routing ⑥Buffer Mgmt Traffic Monitoring and feedback 2616009:Network Traffic Engineering 1:Overview Page.17
2616009: Network Traffic Engineering Feng Gang National Laboratory of Communication, UESTC Aug 2017 Ver 1.4 1: Overview Page.17 An Analogue to Traffic Control: Transportation Traffic Management
Feng Gang National Laboratory of Communication,UESTC Aug 2017 Ver 1.4 A Big Picture Link-level flow and error control:ARQ Flow Control End-to-End reliability and flow control:TCP Open-loop Admission Control,traffic shaping, Congestion Control Packet scheduling Control Closed-loop TCP congestion Contrel,AQM+ECN,TCP over wireless Control A BR Congestion control for ATM networks Traffic Traffic Traffic Shaping Leaky Bucket,Token Bucket Generic Cell Rate Algorithm Control shaping and scheudling Scheduling and drop-tail,priority queuing, and Resource GPS,W eighted Fair Queuing Quening,？, Management QoS Routing Routing QoS M ulticast Routing, reliable m ulticast Buffer Drop strategies management AQM:Random early detection (R ED),FRED,RIO,BLUE, Traffic Traffic m anagem ent:Traffic classes,Time management scales,Mechanisms Traffic Modeling and analysis:queuing, analysis and self-sim ilarity,.. modelling 2616009:Network Traffic Engineering 1:Overview Page.18
2616009: Network Traffic Engineering Feng Gang National Laboratory of Communication, UESTC Aug 2017 Ver 1.4 1: Overview Page.18 A Big Picture T r a f f ic C o n t r o l a n d R e s o u r c e M a n a g e m e n t C o n g e s t io n C o n t r o l T r a f f ic s h a p in g a n d s c h e u d lin g R o u t in g O p e n -lo o p C o n tr o l C lo s e d - lo o p C o n tr o l : A d m is s io n C o n tr o l, tr a ffic s h a p in g , P a c k e t s c h e d u lin g : T C P c o n g e s tio n C o n tr o l, A Q M + E C N , T C P o v e r w ir e le s s A B R C o n g e s tio n c o n tr o l fo r A T M n e tw o r k s T r a ff ic S h a p in g S c h e d u lin g a n d Q u e u in g : d r o p -ta il, p r io r ity q u e u in g , G P S , W e ig h te d F a ir Q u e u in g ,? . : L e a k y B u c k e t , T o k e n B u c k e t G e n e r ic C e ll R a te A lg o r ith m Q o S R o u t in g Q o S M u ltic a s t R o u tin g , r e lia b le m u lt ic a s t B u f f e r m a n a g e m e n t D r o p s tr a te g ie s A Q M : R a n d o m e a r ly d e te c tio n ( R E D ) , F R E D , R I O , B L U E , 厖 . F lo w C o n t r o l L in k -le v e l flo w a n d e r r o r c o n tr o l: A R Q E n d -t o -E n d r e lia b ility a n d flo w c o n t r o l: T C P T r a f f ic m a n a g e m e n t , a n a ly s is a n d m o d e llin g T r a ffic m a n a g e m e n t: T ra ffic c la s s e s , T im e s c a le s , M e c h a n is m s T r a ffic M o d e lin g a n d a n a ly s is : q u e u in g , s e lf-s im ila r ity
Feng Gang National Laboratory of Communication,UESTC Aug 2017 Ver 1.4 Overview of the Traffic Control Objective of Traffic Control and resource management Provide Quality of Service (QoS)guarantee Control the priority and fairness of different service flows Congestion control and prevention Max.Throughput network resource utilization, revenue,..) 2616009:Network Traffic Engineering 1:Overview Page.19
2616009: Network Traffic Engineering Feng Gang National Laboratory of Communication, UESTC Aug 2017 Ver 1.4 1: Overview Page.19 Overview of the Traffic Control • Objective of Traffic Control and resource management - Provide Quality of Service (QoS) guarantee - Control the priority and fairness of different service flows - Congestion control and prevention - Max. Throughput ( network resource utilization, revenue,..)
Feng Gang National Laboratory of Communication,UESTC Aug 2017 Ver 1.4 Core issue in Traffic Control----congestion control 。 What is congestion - The aggregate demand for bandwidth exceeds the available capacity of a link. ·What will be occur2 Performance Degradation Multiple packet losses Low link utilization(low Throughput) ·High queueing delay ·Congestion collapse 2616009:Network Traffic Engineering 1:Overview Page.20
2616009: Network Traffic Engineering Feng Gang National Laboratory of Communication, UESTC Aug 2017 Ver 1.4 1: Overview Page.20 Core issue in Traffic Control----congestion control • What is congestion ? The aggregate demand for bandwidth exceeds the available capacity of a link. • What will be occur ? Performance Degradation • Multiple packet losses • Low link utilization (low Throughput) • High queueing delay • Congestion collapse