January 2007 Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Distributed Channel Time Allocation for WPAN Mesh Networks] Date Submitted: [January 15, 2007] Source: [Young Ae Jeon, Sang Sung Choi, Seung Hyong Rhee, Byungjoo Lee, Wangjong Lee] Company [Electronics & Telecommunications Research Institute / Kwangwoon University] Address [161 Gajeong, Yuseong, Daejeon, 305-700, Korea] Voice:[+82-42-860-6497], FAX: [+82-42-860-6645], E-Mail:[yajeon@etri.re.kr] Re: [Call for additional contributions: IEEE P802.15-06/0333r5] Abstract: [This document suggests to adopt a distributed and self-managed mechanism that achieves a fair channel time allocation and admission control in WPAN mesh networks. It also provides a distributed means for providing QoS differentiation.] Purpose: [Providing technical contributions to IEEE 802.15 TG5] Notice: This document has been prepared to assist the IEEE P802.15. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P802.15. Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Distributed Channel Time Allocation for WPAN Mesh Networks January 2007 Distributed Channel Time Allocation for WPAN Mesh Networks January 2007 Sangsung Choi ETRI/KWU Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Authors Name Company Address Phone E-mail Young Ae Jeon ETRI Korea January 2007 Authors Name Company Address Phone E-mail Young Ae Jeon ETRI Korea +82-42-8606497 yajeon@etri.re.kr Sang Sung Choi +82-42-8606722 sschoi@etri.re.kr Seung Hyong Rhee KWU +82-2-9405441 rhee@ieee.org Byungjoo Lee parang@kw.ac.kr Wangjong Lee woorihope@kw.ac.kr ETRI – Electronics and Telecommunications Research Institute, Daejeon, Korea KWU – Kwangwoon University, Seoul, Korea Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Hierarchy between DEVs and PNC [Shao06a] January 2007 Hierarchy between DEVs and PNC [Shao06a] Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Hierarchical Mesh Architecture [Shao06a] January 2007 Hierarchical Mesh Architecture [Shao06a] MPNC Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Example: Mesh MAC [Hiertz05] January 2007 Example: Mesh MAC [Hiertz05] Superframe equally slotted Medium Access Slots (MAS) Mesh WPAN devices serve .15.3 devices as PNC Reserved MAS for piconet traffic Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

15.5 Scope: Mesh Architecture January 2007 15.5 Scope: Mesh Architecture Agreements Every mesh-capable PNC has to beacon Distributed channel time sharing between mesh devices Mutual coordination of neighbor’s channel time allocation Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Motivation No central controller for the Mesh PNCs January 2007 Motivation No central controller for the Mesh PNCs Among the mesh devices, we still need Fair channel time allocation Decentralized admission control Service differentiation How can the channel time management be done in a distributed and fair manner? Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Problems Could be Hard… January 2007 Problems Could be Hard… Mesh devices will be on the move They may join and leave the network frequently It makes the resource allocation and admission control harder Multimedia traffic transmissions They usually have minimum bandwidth requirements Sometimes exist maximum requirements Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Notation: Reservations among Mesh PNCs January 2007 Notation: Reservations among Mesh PNCs Mesh PNC i reserves duration Ti of MAS Their min/max requirements (mi / Mi) are given Reservation vector T = (T1 ,…,TK ) is feasible if Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Algorithm 1: Computing the Share January 2007 Algorithm 1: Computing the Share Mesh PNCs take turns to make reservations MPNC i , at its turn, Computes T1 Computes T2 Computes Tn ▪ ▪ ▪ ▪ T1 T2 Tn MPNC-1 beacon MPNC-2 beacon MPNC-n beacon C = (reference) MPNC superframe Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Algorithm 2: Admission Control January 2007 Algorithm 2: Admission Control Mesh PNC i makes a self-decision for joining the mesh network During one Mesh Superframe, read m1 read m2 read mn decision ▪ ▪ ▪ ▪ m1 m2 mn MPNC-1 beacon MPNC-2 beacon MPNC-n beacon C = (reference) MPNC superframe Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Example: Fairness & Convergence (1) January 2007 Example: Fairness & Convergence (1) DTP length: 100 MAS α1 = α2 = α3 = 0.5 Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Example: Fairness & Convergence (2) January 2007 Example: Fairness & Convergence (2) DTP length: 100 MAS α1 = α2 = α3 = 0.25 DTP length: 100 MAS α1 = α2 = α3 = 0.75 Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Example: Service Differentiation January 2007 Example: Service Differentiation α1 = 0.5 α2 = 0.66 α1 = 0.5 α2 = 0.75 Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Example: Minimum Requirements January 2007 Example: Minimum Requirements Min requirement of MPNC1: 30 MAS α1 = α2 = α3 = 0.5 Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Example: Join/Leave of MPNCs January 2007 Example: Join/Leave of MPNCs Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Analytical Modeling [Rhee06] January 2007 Analytical Modeling [Rhee06] Our resource allocation mechanism can be modeled as follows: where Ui is a strictly concave real function such that Given C and T = (T1 ,…,TK ), this is a distributed optimization problem among the devices Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Gauss-Seidel Type Iteration January 2007 Gauss-Seidel Type Iteration We adopt the Gauss-Seidel type iteration Only one component of T is updated at a time The most recent information is available to the devices Let T(t) = (T1(t), …, TK(t)), our iterative equation is T(t+1) = F(T(t)), t = 0,1,… In our implementation, T(t) and T(t+1) are different only in their ith element MPNC obtains info on T(t) from previous beacons MPNCs are asynchronous: no pre-specified order among them Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

January 2007 Our Proof Shows that All MPNCs converge to a unique equilibrium point T*, regardless of Number of MPNCs The values of αi and min/max requirements [mi , Mi] Their reservations converge to T* Always within a finite time The amount of allocation at the equilibrium is Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Multi-Hop Mesh PNCs January 2007 Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Example: Multi-Hop Mesh PNCs January 2007 Example: Multi-Hop Mesh PNCs MPNC 1, 2 &3 MPNC 3 & 4 Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

Conclusion Distributed channel-time allocation for mesh WPANs January 2007 Conclusion Distributed channel-time allocation for mesh WPANs Fair allocation without a controller Decentralized admission control Service differentiation Analytical modeling proves Self-stabilizing property of our algorithm Fair and differentiated allocation Correctness of the simulation results Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>

January 2007 References [Shao06a] Shao et al, “IEEE P802.15.5 Draft candidate,” IEEE P802.15-06/0237r2, July 2006 [Shao06b] H. Shao, “Call for additional contribution for 802.15.5 Mesh Networking,” IEEE P802.15-06/0333r5, July 2006 [Hiertz05] Hiertz et al, “Mesh PAN Alliance (MPA) and .15.3 integration,” IEEE P802.15-05/0670, Nov. 2005 [Rhee06] Rhee et al, “Self-managed multiple access control for the distributed wireless PANs,” submitted to a journal Jeon, Choi, Rhee, Lee and Lee <ETRI/KWU>