Mesh Media Access Coordination Ad Hoc Group Report Out July 2004 doc.: IEEE 802.11-04/1077r0 Sept 2004 Mesh Media Access Coordination Ad Hoc Group Report Out L. Lily Yang (Intel Corp.) lily.l.yang@intel.com Lily Yang Lily Yang

Ad Hoc Group Activities since Portland meeting July 2004 doc.: IEEE 802.11-04/1077r0 Sept 2004 Ad Hoc Group Activities since Portland meeting One face to face meeting at Portland, 07-25-04 Decided to first focus on a list of issues in MAC Set up a WiKi page for the group: http://ieee.comnets.rwth-aachen.de/cgi-bin/wiki.pl?MeshMediaAccessCoordinationGroup One teleconference call, 08-19-2004 Clarified the scope of the ad hoc group: Mesh Media Access Coordination Function Changed the group name Worked on the issue list More discussion over emails on the issue list Outcome of the group: #968r05 Lily Yang Lily Yang

Mesh Point Reference Architecture Sept 2004 Mesh Point Reference Architecture Configuration/ Management Internetworking Interfaces IEEE802.11s Amendment .11s Mesh Network Measurement Layer 2 Mesh Routing and Forwarding .11s Mesh Security Mesh Media Access Coordination Function IEEE802.11 MAC IEEE802.11　PHY IEEE802.11 a/b/g/j/n *[1] slide#3 Lily Yang

Purpose of #968 (Issue List) Sept 2004 Purpose of #968 (Issue List) Informational: provide suggestions on what are the technical challenges the 11s proposal might want to address for Mesh Media Coordination Function NOT a requirement document FLAT list of issues: No significance to the order No prioritization done to the list yet Up to TGs to decide What is the minimum requirements What is out of scope What is optional Lily Yang

Two Operational Phases Sept 2004 Two Operational Phases Mesh Discovery and Mesh Link Establishment (Section 3 in #968) Mesh Discovery: mesh beacon? Link Establishment: Mesh authentication? Mesh association? Normal Operational Phase (Section 4 in #968) Mesh Media Access Coordination Function is in action Lily Yang

List of Issues in Mesh Media Access Coordination Function Sept 2004 List of Issues in Mesh Media Access Coordination Function 11 Issues documented in 968 Most are needed due to the “mesh” nature Missing or inadequate in current 11/11e MAC Opportunities presented by mesh Lily Yang

Issue #4.1 Hidden Terminal Problem Sept 2004 Issue #4.1 Hidden Terminal Problem hidden nodes: nodes in I(R) but not S(T) T R H S(T): Sensing range of T I(R): Interference range of R Lily Yang

Issue #4.1 Performance Impact July 2004 doc.: IEEE 802.11-04/1077r0 Sept 2004 Issue #4.1 Performance Impact STA1 STA2 STA3 STA4 Case (a) Case (c) STA1 STA2 STA3 STA4 Case (b) Case (b) Case (d) Case (a) Case (c) Case (d) Lily Yang Lily Yang

Issue #4.2 Exposed Terminal Problem Sept 2004 Issue #4.2 Exposed Terminal Problem E T R hidden nodes: nodes in S(T) but not in I(R) S(T): Sensing range of T I(R): Interference range of R Lily Yang

Issue #3 Flow Control from source to destination Sept 2004 Issue #3 Flow Control from source to destination 11 DCF: packet-based fairness 11e EDCA (TXOP): time-based fairness Fixed slow client problem for BSS Improve BSS network throughput But may introduce problem for multi-hop path with multi-rate 11 mb/s 2 mb/s Lily Yang

Issue #4.3 Another Flow Control Example Sept 2004 Issue #4.3 Another Flow Control Example Individual flow throughput (b/s) N0 N4 N1 N2 N3 Flow 1 Flow 2 Load (mb/s) Lily Yang

Lack of Flow Control: Example (cont.) Sept 2004 Lack of Flow Control: Example (cont.) Actual Scheduling Result when load=700kb/s e2e throughput 674k 449k 355k 235k Congested nodes 238k 347k 450k 697k Rx: 238k 1020k 899k 1056k 235k Tx: 674k 687k 702k 685k 697k Wasted TX Ideal Scheduling, when the network is overloaded 430k 430k 430k 430k 430k 430k 430k 430k e2e throughput Rx: 430k 860k 860k 860k 860k Tx: 430k 860k 860k 860k 430k Lily Yang

Issue #4.4 Mesh Load Balance Sept 2004 Issue #4.4 Mesh Load Balance Lily Yang

Issue #4.5 Multi-hop Scheduling Sept 2004 Issue #4.5 Multi-hop Scheduling Lily Yang

Issue #4.6 Distributed Admission Control Sept 2004 Issue #4.6 Distributed Admission Control 11s Admission Control 11e Admission Control Mesh AP STA Lily Yang

Issue #4.7 Distributed QoS Management Sept 2004 Issue #4.7 Distributed QoS Management Mesh AP STA Lily Yang

Issue #4.8 Mixture of BSS Traffic and Forwarding Traffic Sept 2004 Issue #4.8 Mixture of BSS Traffic and Forwarding Traffic Relay traffic Mesh AP STA N4 N0 N1 N2 N3 BSS traffic When Mesh Point co-located with AP on one RF interface: How to coordinate the relay traffic for mesh point and the BSS traffic for AP? Lily Yang

Issue #4.9 Scalability Different usage models: Variable: Sept 2004 Issue #4.9 Scalability Different usage models: Small home Medium size office Large campus and community network Variable: Network size Node density Fixed EDCA parameters? Lily Yang

Issue #10 Channelization Sept 2004 Issue #10 Channelization A A->B: channel n C->D: channel m D C B Lily Yang

Issue #11 Multiple Radios Sept 2004 Issue #11 Multiple Radios Mesh AP Mesh Point BSS traffic To/from Stations Forwarding Traffic from/to Other Mesh Points Using multi-radio to implement channelization Lily Yang

Sept 2004 Summary A list of issues should be paid attention to when making proposals to 11s Open Questions: Is this useful to TGs? Anything here that must be addressed by 11s as hard (minimum) requirements? How do we intend to measure the Mesh Media Access Coordination Function performance of the proposals? Should we derive some simulation scenarios from this list so that different aspect of the performance can be evaluated? Lily Yang

July 2004 doc.: IEEE 802.11-04/1077r0 Sept 2004 References [1] 11-04-0749-00-000s-suggested-major-functional-components-802-11s.ppt [2] 11-04-0968-05-000s-issues-for-mesh-media-access-coordination-component-in-11s.doc Lily Yang Lily Yang