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On Admission Control in Qos-Aware PON System. Front.SJTU Boven Yan April 15 th 2011. Admission Control (AC) in PON. Work Status: Introduce the status of AC in PON research. Problems involving DBA. Grant Sizing Allocates adequate transmission window for each ONU
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On Admission Control in Qos-Aware PON System Front.SJTU Boven Yan April 15th 2011
Admission Control (AC) in PON Work Status: Introduce the status of AC in PON research
Problems involving DBA • Grant Sizing Allocates adequate transmission window for each ONU • Grant Scheduling (inter ONU scheduling) Specify a certain transmission order for different ONUs • Queue Scheduling (intra ONU scheduling) Enable differentiate service flows
Supporting Differentiated Service • Bandwidth and Delay GuaranteeQos-standard for different services: • EF: Expedited fowarding (VoIP) • delay sensitive, bounded jitter specification. • AF: Assured fowarding (secured web operation) • not delay sensitive but require bandwidth guarantees • BE: Best effort service (e-mail) • neither delay sensitive nor require jitter specification • Fairness • Fair share of network resource (often by offline DBA) • A minimum bandwidth guarantee • Unused Bandwidth be redistributed.
Supporting Differentiated Service • Admission Control (what currently engaged in) Decide whether to accept a Qos specified service according to the current resource allocation over the system.
Admission Control (AC) in PON system Concept and Aim of Research
Admission Control on PON system • Why should consider AC • The upper limit of PON system in satisfying services; • Requirements of Qos request under heavy load; • A qualified AC solution should satisfying: • Highly efficient use of uplink bandwidth. • Providing Qos-aware service • A high accept receiving ratio of service (PON ability) • * Should cost little at light load condition as well • Compared with past works • Focusing on full use of bandwidth and decrease delay without considering about practical limit of satisfying • these service as a system.
Admission Control (AC) in PON system Per stream Control based AC strategy [1] Dhaini, A.R.; Assi, C.M: Per-Stream QoS and Admission Control in Ethernet Passive Optical Networks, JLT, 2007 [2] Dhaini, A.R.; Assi, C.M: ;Toward Quality of Service Protection in Ethernet Optical Networks Challenges and Solutions, IEEE Network, 2007 [3] Dhaini, A.R.; Assi, C.M: Admission Control in Ethernet Passive Optical Networks (EPONs) ,ICC,2007 [4] Maode Ma, Yongqing Zhu, Tee Hiang Cheng: A Bandwidth Guaranteed Polling MAC Protocol for Ethernet Passive Optical Networks, 2003
Per stream Control based AC strategy • A per stream basis: • Each ONU has accept 3 types of service and queue up at the ONU side. Each ONU manage a three-subqueue service flow. • Service are accept on per stream basis with different Qos standard. • The Qos ability of the EPON is indirectly correlated to the bandwidth allocation and cycle time.
Per stream Control based AC strategy • Bandwidth allocation: • Local AC: • Global AC:
Per stream Control based AC strategy • Potential Problems • Burstiness of real-time traffic Bandwidth guarantee strategy will waste bandwidth • Solution: (a two-branch sol.) • Super Tcycle for large service flow • Credit mechanism for CBR and VBR service
Per stream Control based AC strategy • AC-DBA:
Admission Control (AC) in PON system Deterministic QoS Provisioning with Network Calculus Based Admission Control in WDM EPON Networks [1] Daojun Xue, Yang Qin, Chee Kheong Siew: Deterministic QoS Provisioning with Network Calculus Based Admission Control in WDM EPON Networks ,ICC,2009 [2] Chee Kheong Siew, Daojun Xue and Yang Qin: Providing deterministic quality of service in slotted optical networks 2006
Deterministic Qos Service AC strategy based on Network Calculus Theory in WDM TDM PON • What is Network Calculus? A Description of flow and serving system model. • Basic concept of Network Calculus. A system is modeled by an min-plus convolution, and input output is “shaped” by curves of the system, making the input and output flow bear a series of characteristics. Interested readers may refer to [2] for detailed information [2] A SHORT TUTORIAL ON NETWORK CALCULUS I: FUNDAMENTAL BOUNDS IN COMMUNICATION NETWORKS IEEE ISCS 2000
Deterministic Qos Service AC strategy based on Network Calculus Theory in WDM TDM PON • Model of an system: • Arrival curves: Service curves:
Deterministic Qos Service AC strategy based on Network Calculus Theory in WDM TDM PON • Dynamical Wavelength Allocation Architecture
Deterministic Qos Service AC strategy based on Network Calculus Theory in WDM TDM PON • Admission Control Scheme: • Assumption: Deterministic Service Resource: Total Bandwidth: Cw, Limit: total share of bandwidth: satisfying Qos Requirements: Optimize: Token bucket chosen:
Deterministic Qos Service AC strategy based on Network Calculus Theory in WDM TDM PON • Scheduling Strategy: • Classify the arriving flow (ρnew, σnew, dnew) into the Qos queue according to: • Report to OLT • Scheduling
Deterministic Qos Service AC strategy based on Network Calculus Theory in WDM TDM PON
OFDM PON Tech Supporting tech of OFDM [1] Jean Armstrong: OFDM for Optical Communications 2008
Supporting tech of OFDM • Benefits physically: • Noise capacity of the system is dominated by the average power of the noise. (Fourier Transform) • Multipath interference can be eliminate using cyclic prefix and a ‘single tap’ equalizer(low computing complexity). (Wireless … Optical?) • Benefits service related: • Subfrequency enables various type of service including Wimax and Analog service. • Drawbacks physically: • High requirements for devices, sensitivity to evironment
OFDM PON Tech PON Structure [1] Xi Zheng, Xiao liu, Chunning Hou, Yufeng Shao, Shumin Zou, Xinying Li, Junwen Zhang, Wuliang Fang, and Nan Chi A Novel OFDM-PON architecture using single-side-band OFDM for down stream and sub-carrier multiplexed ASK for up stream 2008 [2] Zhihua Zheng, Zongjue Qian, Guochu Shou, Yihong Hu: OFDMA System with Dynamic Bandwidth Allocation in Passive Optical Networks 2009
Combination of two work Qos-Aware Scheduling on OFDM PON System
Qos-Aware Scheduling on OFDM PON System • Combining the analysis of WDM PON system • Difference of OFDM and WDM system. • Larger bandwidth resource • Greater flexibility of service (Grouping idea) • Flexibility of OFDM PON System • Qos Aware, Dynamical wavelength allocation • Aim: to achieve better switch among high load and low load ONUs • Further work, Admission Control on OFDM system • Aim: to integrate AC analysis of WDM system and OFDM system.
Other Work OPNET PON Simulation