Discussion of 802.16n System Requirements IEEE 802.16 Presentation Submission Template (Rev. 9) Document Number: C802.16gman-10/0011r2 Date Submitted: 2010-05-10 Source: Eldad Zeira E-mail: eldad.zeira@interdigital.com Interdigital Communications LLC Re: Call for contributions: SRD for 802.16n Purpose: To be discussed by the SG Notice: This document does not represent the agreed views of the IEEE 802.16 Working Group or any of its subgroups. It represents only the views of the participants listed in the “Source(s)” field above. It is offered as a basis for discussion. It is not binding on the contributor(s), who 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 802.16. Patent Policy: The contributor is familiar with the IEEE-SA Patent Policy and Procedures: <http://standards.ieee.org/guides/bylaws/sect6-7.html#6> and <http://standards.ieee.org/guides/opman/sect6.html#6.3>. Further information is located at <http://standards.ieee.org/board/pat/pat-material.html> and <http://standards.ieee.org/board/pat >. 802.16n PAR: Scope1 • This amendment specifies protocol enhancements to the IEEE 802.16 MAC for enabling increased robustness and alternate radio path establishment in degraded network conditions. Limited OFDMA PHY extensions are included for enabling operation with radio path redundancy and direct communication between subscriber stations. Also mobile base stations and mobile relay stations are supported. Support for enabling application specific specialized security suites is also provided. • With the added note: • Operation in licensed, unlicensed and lightly licensed spectrum bands below 6 GHz with means and mechanisms to coexist with other radio access technologies (RATs) is supported. 1 5/5/2010 See background material for relevant definitions C80216gman-10/0011 2 M2M may have similar requirements: • From latest M2M draft SR: 80216ppc-10_0002r6 – In advanced architecture “peer-to-peer (P2P) connectivity between IEEE 802.16 M2M devices may also be supported” – High reliability is required “regardless of operating environment” and “device collaboration and redundant and/or alternate paths are indirect methods of improving reliability” MNO (Mobile Network Operator) Access Service Network IEEE 802.16 Non M2M device IEEE 802.16 M2M device Connectivity Service Network R1 R1 M2M Server M2M Service Consumer IEEE 802.16 BS 5/5/2010 Non IEEE 802.16 M2M device IEEE 802.16 M2M device IEEE 802.16 M2M device IEEE 802.16 M2M device C80216gman-10/0011 R1 R1 3 Scope derived requirements • “Enabling … alternate radio path establishment in degraded network conditions, …, radio path redundancy in degraded network…” • “… and direct communication between subscriber stations” • “mobile base stations” • “mobile relay stations” • “specialized security suites” 5/5/2010 C80216gman-10/0011 4 Breakdown: robustness - what is it? • “Enabling increased robustness… alternate radio path establishment in degraded network conditions, …, radio path redundancy in degraded network…” • Practical goal: immunity to “Single Point of Failure” (SPOF) – Including any network node or radio path to network node or its backhaul – MS failure itself out of scope • Immunity to SPOF achieved as long as deployment is “dense” enough to provide an alternative path • Any connection availability probability can be provided (e.g. 99.9% required for Smart Grid) – it is up to deployment 5/5/2010 C80216gman-10/0011 5 Robustness – how to provide? • Re-scan: an existing solution that requires a very dense BS deployment • Without MS support, “Network Solution” – No MS modifications – Other solutions require: • A BS-BS data transfer mechanism – Topology? (direct, intermediary), Infrastructure node density – Protocol structure • Specialized nodes (special BS, RS) – More suitable to extended range applications with lower latencies (reduces number of hops) 5/5/2010 C80216gman-10/0011 6 Robustness – how to provide – cont’d • With MS-MS direct communication – No specialized nodes required (all MS nodes are specialized) – Fewer bottlenecks – Issues: • What is the role of the network, if any? • Not all MS can see any BS! • MS-MS direct communication has other uses too 5/5/2010 C80216gman-10/0011 7 HR-Network robustness examples 1 HR-BS HR-BS 2 HR-RS 3 5 4 BS (1) has lost its backhaul, can now convey user data to another BS directly (2) or through relay (3). MS (4) and (5) lost communication with serving BS, now using other MS to connect 5/5/2010 C80216gman-10/0011 8 Direct communications – what is it? • “… and direct communication between subscriber stations” • Possible uses for direct communication: – – – – (robustness – see above) Coverage extension (coverage holes, robustness) Traffic aggregation / relaying (M2M?) Throughput enhancement for local traffic (CE, others) • Issues: – BS / network support & control – Dependency of BS / network support 5/5/2010 C80216gman-10/0011 9 Topology mapping for MS-MS communications Requirement Data rate BS availability MS autonomy Multi-hop relaying Robustness Any Partial Partial Required ? Coverage extension Any Partial Partial Optional Traffic aggregation / relaying Low to medium Partial Partial Optional Always (control only) Not required Not required Localized Medium to traffic handling High 5/5/2010 C80216gman-10/0011 10 Illustration of MS-MS topologies HR-RS M1 3 HR-BS M2 M7 1 M6 M5 M3 M4 2 (1) M6 and M7 transfer data directly while being both connected to a base station; (2) M4 cannot receive the BS, receives its data through M5 in an MS-MS-BS configuration; (3) M3 receives its data through M2, M1 and the relay HR-RS 5/5/2010 C80216gman-10/0011 11 Security: what is it? • specialized security suites • Existing 802.16m requirements handle only MSBS, BS-RS and MS-RS configurations. • MS-MS and other topologies, e.g. as required for network recovery will likely require new security procedures 5/5/2010 C80216gman-10/0011 12 Mobile BS – what is it? • mobile base stations 5/5/2010 C80216gman-10/0011 13 Mobile RS – what is it? • mobile relay 5/5/2010 C80216gman-10/0011 14 Background 5/5/2010 C80216gman-10/0011 15 PAR agreed Definitions Degraded Network The failure of one or more 802.16 network infrastructure nodes or network connectivity Robustness The capability of the network to withstand and automatically recover from degradation to provide the required availability to support mission critical applications (essential to the core function of society and the economy). E.g. the ability to recover from a single point of failure Mobile Base Station A base station which is capable of maintaining service while moving Radio Path Redundancy 5/5/2010 The ability to provide alternative paths between base stations, relay stations, and subscriber stations C80216gman-10/0011 16 Other useful definitions HR-MS HR-BS HR-RS HR-network Minimal QoS Radio connectable 5/5/2010 A subscriber station that complies with the requirements for subscriber stations in this amendment A base station that complies with the requirements for base stations in this amendment A relay that complies with the requirements for relays in this amendment A network whose nodes comply with their respective requirements in this amendment The combination of data rate, latency and other relevant parameters that are considered necessary to establish a radio link The ability of any two nodes to communicate directly at a certain minimal QoS C80216gman-10/0011 17