Multihop Wireless Networks

Transcription

1 Multihop Wireless Networks Ray-Guang Cheng Associate Professor Department of Electronic Engineering, National Taiwan Univ. of Science and Technology, Taipei, Taiwan

2 Outline Introduction Multihop Wireless Networks Status of Selected Standards Case Study: WIFLY 2

3 Introduction Multihop Wireless Network (MWN): A wireless network adopting multihop wireless technology without deployment of wired backhaul links Similar to Mobile Ad hoc Networks (MANET), but Nodes in MWN is relative fixed MWN may introduce hierarchy network architecture 3

4 Multihop Wireless Networks Two categories: Relay: Tree based topology, one end of the path is the base station Dedicated carrier owned infrastructure Mesh: Mesh topology, multiple connections among users Routing by carrier owned infrastructure or subscriber equipment 4

5 Multihop Wireless Networks Benefit of multi-hop technology Rapid deployment with lower-cost backhaul Easy to provide coverage in hard-to-wire areas Under the right circumstances, it may Extend coverage due to multi-hop forwarding Enhance throughput due to shorter hops Extend battery life due to lower power transmission Price paid Routing complexity Path management Extra delay due to multihop relaying 5

6 Related Standards & Proposals Relay 3GPP Opportunity Driven Multiple Access (ODMA), a communication relaying protocol proposed for UMTS TDD mode IEEE IEEE j, Multihop relay (MR) enhancement of IEEE e (Mobile WiMAX) 6

7 Related Standards & Proposals Mesh IEEE IEEE s, ESS Mesh Networking enhancement of IEEE IEEE IEEE WPAN Mesh Networking Extend coverage and enhance reliability IEEE MAC layer mesh extension of IEEE , optional mode, no one implement it due to its complexity 7

8 IEEE j Multihop Relay 8

9 BS IEEE j Deployment Scenarios Fixed Infrastructure In-Building Coverage Temporary Coverage Coverage On Mobile Vehicle 9

10 16j Progress History Pre-Study Phase (May ~ July 2005) Scope and Purpose discussion: Mobile Multihop Relay Study Group was chartered in July 2005 Study Group Phase (Sep ~ Mar. 2006) Feasibility discussion PAR (Project Authorization Request) approved in March Task Group Phase (May 2006 ~ Now ) Relay TG Chair: Mitsuo Nohara, KDDI Lab. Guideline Document Discussion (May ~ Sep. 2006) Baseline Document (Spec.) Discussion (Nov ~ Now) 1st Letter Ballot on P802.16j/D1 failed (67%, Aug. 2007) 1059 comments submitted in Meeting #51, resolved in Meeting #52 (Nov. 2007) P802.16j/D2 WG Letter Ballot on j/D2 631 comments submitted and resolved in Meeting #53 P802.16j/D3 10

11 IEEE s Source: IEEE s Tutorial 11

12 IEEE s Deployment Scenarios Residential Office Military Public Access Public Safety University Campus Community Area Park Area 12

13 11s Progress History Pre-Study Phase (Nov. 2003) Scope and Purpose discussion IEEE ESS Mesh Study Group was chartered Study Group Phase (Jan ~ May 2004) Feasibility discussion PAR (Project Authorization Request) approved in May Task Group Phase (July 2004 ~ Now ) Call for proposal (Jan. 2005), 15 proposals were presented until July 2005 Baseline Document (Spec.) Discussion (Mar ~ Now) 1 st Letter Ballot on P802.11s/D1 failed (48.3%, Dec. 2006) P802.11s/D2 is approved in Jan. 2008, which is ready for the 2 nd Letter Ballot (Feb. 2008) 13

14 Case Study: WIFLY M-Taipei: adopts Wi-Fi technology to build the network calls for a build-and-operate (BO) tender that grants a nine-year franchise of construction and operation without transferring networking facilities permits Q-ware Systems to install access points (APs) on all city-owned public facilities Up to now, 4600 APs are installed in an area of about km 2, where 90% of the population resides 14

15 WIFLY: Network Construction Phase-1:(Sep.~Dec. 2004) 30 MRT stations, malls, neighboring (150 m) areas (20% population coverage) Phase-2: (Dec. 2004~Dec. 2005) Core area of Taipei city (50%) Phase-3: (Dec. 2005~June. 2006) All other area in Taipei city (90% ) 15

16 WIFLY: Rate Options Post-paid 399 NTD (~ 1319 )/month 4,200 NTD (~ )/year Pre-paid PC/NB (hot-spots) 100 NTD (~331 )/day 500 NTD (~1653 )/month 300 NTD (~992 )/360mins PDA/SONY PSP (retail channels) 1800 NTD (~5950 )/year ipod touch (retail channels) 1200 NTD (~3967 )/year 16

17 WIFLY Transportation Services - I 17 17

18 WIFLY Transportation Services - II 18

19 Reference Multihop wireless network R. Jain, Wireless Mesh and Multi-Hop Relay Networks, R. B. Marks, et al., IEEE 802 Tutorial: Mobile Multihop Relay, IEEE mmr-06/006, March W. S. Conner, et al., IEEE s Tutorial Overview of the Amendment for Wireless Local Area Mesh Networking, IEEE s Tutorial, Nov M-Taipei:

20 Thank you!