140 likes | 369 Views
期中報告. CCUCOMM 網路前瞻實驗室 Yi-Chi Cheng 鄭伊騏. Outline. Introduction HTB Future Work. Hierarchical Token Bucket (1/2). HTB is one of the packet scheduler. It is currently included in stock Linux kernels from 2.4.20. Control the use of the outbound bandwidth on a given link.
E N D
期中報告 CCUCOMM網路前瞻實驗室Yi-Chi Cheng 鄭伊騏 ANT LAB@CCU COMM
Outline • Introduction • HTB • Future Work ANT LAB@CCU COMM
Hierarchical Token Bucket (1/2) • HTB is one of the packet scheduler. It is currently included in stock Linux kernels from 2.4.20. • Control the use of the outbound bandwidth on a given link. • Using one physical link to simulate several slower links. ANT LAB@CCU COMM
Hierarchical Token Bucket (2/2) • Send different kinds of traffic on different simulated links. • Ensures that the amount of service provided to each class is at least the minimum of the amount it requests and the amount assigned to it. • Allow “lower” priority queue to borrow the bandwidth form the higher priority queue when it’s idle. ANT LAB@CCU COMM
Traffic control for Linux (1/3) • Consist of Queuing disciplines (Qdisc) , classes and filters. filter queuing discipline class packet filter class queuing discipline filter queuing discipline function ANT LAB@CCU COMM
Traffic control for Linux (2/3) • Filter • 依據封包的來源不同(IP或port),來決定其Class • Class • 依據Application及Data type不同,分送到不同的Queuing Discipline • Queuing Discipline • 不同的Qdisc會有不同的排程方式,如:FIFO ANT LAB@CCU COMM
Traffic control for Linux (3/3) • Classful qdisc : CBQ, HTB • Classless qdisc : FIFO, TBF, RED • Application Aware: • 固定port • Dynamic port:依據signaling內容來處理 ANT LAB@CCU COMM
Introduction • AR: Assure rate • CR: ceil rate • Mode: • Red:R>CR [HTB_CANT_SEND] • Yellow:R ≦ CR and R > AR [HTB_MAY_BORROW] • Green:otherwise [HTB_CAN_SEND] ANT LAB@CCU COMM
Future Work • Measure the performance of the VoIP transmission with HTB and without HTB. • Find out why HTB can’t run so precisely? ANT LAB@CCU COMM