1. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 1 Broadband V2I Access for High Speed Transportation Notice: This document has been prepared to assist IEEE 802.11. 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 grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE 802.11. Patent Policy and Procedures: The contributor is familiar with the IEEE 802 Patent Policy and Procedures, including the statement "IEEE standards may include the known use of patent(s), including patent applications, provided the IEEE receives assurance from the patent holder or applicant with respect to patents essential for compliance with both mandatory and optional portions of the standard." Early disclosure to the Working Group of patent information that might be relevant to the standard is essential to reduce the possibility for delays in the development process and increase the likelihood that the draft publication will be approved for publication. Please notify the Chair as early as possible, in written or electronic form, if patented technology (or technology under patent application) might be incorporated into a draft standard being developed within the IEEE 802.11 Working Group. If you have questions, contact the IEEE Patent Committee Administrator at.http:// ieee802.org/guides/bylaws/sb-bylaws.pdfstuart.kerry@philips.compatcom@ieee.org Date: 2009-5-12 Authors:

2. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 2 Abstract We talk about WLAN broadband access for high speed transportation. –Motivation –Market –Applications –Why Wi-Fi? –Why standardization is needed? –Requirement Handover Latency Case Study –Comparison with Existing IEEE802.11 Standards –Straw Poll

3. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 3 Motivation Many high speed trains (>200km/h) are already in operation in Europe and Asia. Developments of 10,000km of express railway tracks are estimated in next 20 years in the world. Train operators want broadband network between rail-side and train for such as train survey, passenger service and so on. And they want to operate the network by their own. Wi-Fi will meet their needs. (Equipments cost, Operation cost, Bandwidth…)

4. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 4 Markets Train (Railway Transportation) Total extension of railway is approximately 1,350,000km in the world. –North America:278,000km –EU:236,000km –Russia:128,000km –East Asia:110,000km –Central/South America:110,000km Existing high speed train (> 200km/h operation) –22 systems in operation in 15 countries. Expected new high speed train –10,000km in next 20 years. –In US, President Obama unveiled his plan to develop new high speed passenger railway. Of cause, not only high speed train but also ordinary train can use this technology. NameCountryMax. Speed Shanghai Transrapid China430km/h Beijing-Tianjin HSCL China350km/h TGVFrance320km/h ICEGermany320km/h ShinkansenJapan300km/h AVESpain300km/h EurostarEU300km ThalysEU300km/h Treni Eurostar Italia Italy300km/h Taiwan HSRTaiwan300km/h KTXKorea300km/h Existing High Speed Train (> 300km/h)

5. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 5 Expected Applications Hot-spot service for passengers. Passenger information services. Cabin monitoring. Backbone for femtocell. –Subway –Tunnel Internet

6. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 6 Backbone for Hot-spot Service WLAN AP LAN Train STA Roadside AP Web Servers Mail Servers Misc. Servers Internet Passengers can access to the Internet while traveling at low price and high speed. Web Servers

7. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 7 Backbone for Femtocell Femtocell LAN Train STA Roadside AP Cellular Phone Network Internet Passengers can use their celluler phone even in a tunnel or underground. Cellular Phone Network

8. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 8 Passenger Information Services LAN Train STA Roadside AP Passengers can get information such as news, travel information, advertisement in real time. News Advertisement Travel Info… Info. Servers Internet Info. Servers

9. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 9 Cabin Monitoring LAN Train STA Roadside AP Train operators can monitor the cabin. Internet

10. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 10 Why Wi-Fi? StandardsBandwidthEquipment CostOperation Cost 3G, 3.5G 14.4Mbps (Downlink) 11.5Mbps (Uplink) Very HighHigh LTE 100Mbps (Downlink) 50Mbps (Uplink) Very HighHigh WiMAX (IEEE802.16e)21MbpsHighLow IEEE802.11 100Mbps (11n MAC) Low Wi-Fi can be easily operated by train/railway operators. It means the networks are under their control, not rely on others. And Wi-Fi has world-wide interoperability on frequency use.

11. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 11 Why standardization is needed? Multiple vendor and long term support is needed for sustainable operation. A train may run across multiple railway network. So inter-/intra-national interoperability is needed. According to these reasons, international standardization is needed.

12. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 12 Requirements Target Speed –TGV plans 360km/h operation. –TransRapid in Shanghai is operated in 430km/h. –JR-Maglev records 581km/h and JR plans to start service in 2025. –500km/h is enough? Scalability –Many trains are running on a railway simultaneously. –Railway networks are vast. So a train may run across many communication networks. –Inter-network handover is required. Security –Security is very important because private information will flow on networks. –For example, a train survey application will transfer a video which includes a passenger’s face.

13. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 13 Inter-Network Use Network A AP Network B AP Network C AP Network D Inter-Network Handover IEEE802.11r does not support inter-network handover.

14. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 14 Inter-network Handover Latency 1.Discover a new AP. Latency can be reduced by 11k or multiple radio interfaces. 2.Association with new AP. (includes authentication/key exchange…) 11i authentication is NOT fast. It needs many packet exchanges. 3.Network layer setup.

15. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 15 MAC Requirements Fast Association –Train must handover during passing overlap zone for seamless handover. –Handover latency impacts distance between APs. (= cost) –Low handover latency is needed. Old APNew AP Overlap Zone

16. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 16 Case Study Assumption –Maximum speed: 500km/h = 140m/s –Cell Radius: 200m –Route Length: 1,000km Old APNew AP Case 1:Handover Latency = 100ms Minimum Overlap Zone length= 14m Distance between adjacent APs = 386m Number of APs = 2,591 14m 200m 386m

17. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 17 Case Study (cont.) Old AP Case 2:Handover Latency >1.43s Minimum Overlap Zone distance > 200m 200m New AP STA must begin new handover process before completing old handover process.

18. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 18 Protocol Sequence of IEEE802.11+IEEE802.1x(EAP-MD5) STAAPRADIUS Server Beacon Probe Request Probe Response Authentication Request Authentication Reply Association Request Association Accept EAPOL-Start EAP-Request/Identity EAP-Response/Identity EAP-Request/Credentials RADIUS-Access-Request RADIUS-Access-Challenge EAP-Response/Credentials EAP-Success RADIUS-Access-Request RADIUS-Access-Accept At least 6 roundtrip packet exchanges between STA and AP, and 2 roundtrip packet exchanges between AP and RADIUS server are needed. EAP-TLS, EAP-TTLS, etc. needs more packet exchanges. It increases handover latency

19. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 19 Comparison with Existing IEEE802.11 Standards Standards Inter-Network Use Security Fast Roaming (Handover) IEEE802.11/a/b/g/n +IEEE802.11i +IEEE802.11r We need Approaches a.Fast authentication/key exchange. b.Inter-network fast roaming.

20. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 20 PHY Compatibility Existing PHY can be used in high speed environment. (08/1020r1) So existing WLAN chipset can be used with some firmware and/or driver modification. LOW COST

21. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 21 Questions & Comments

22. doc.: IEEE 802.11-09/0111r2 Submission May 2009 Hitoshi MORIOKA, ROOT Inc.Slide 22 Straw Poll “A Study Group to develop a PAR and 5C for High- speed Broadband Access for 802.11 should be created” Yes: No: Don’t Know, Need More Discussion: Don’t Care: