Suggested Clarification of 802.11s ESS Mesh Terminology W. Steven Conner (Intel Corp.) Yoichi MATSUMOTO, Hidenori AOKI (NTT DoCoMo) May 12, 2004

Defining consistent terminology for ESS Mesh Benefits of adopting common terminology early in the process Promote consistent use of new terminology to describe ESS Mesh, usage models, requirements, etc. Help participants to speak the same language when describing ESS Mesh technology

Existing 802.11 terms that are relevant to “ESS Mesh” basic service set (BSS): A set of stations controlled by a single coordination function. (3.7) distribution system (DS): A system used to interconnect a set of basic service sets (BSSs) and integrated local area networks (LANs) to create an extended service set (ESS). (3.20) A DS may be created from many different technologies including current IEEE 802 wired LANs. (5.3) extended service set (ESS): A set of one or more interconnected basic service sets (BSSs) and integrated local area networks (LANs) that appears as a single BSS to the logical link control (LLC) layer at any station associated with one of those BSSs. (3.25)

What Standard 802.11 Services Exist Today for Building an ESS? Includes Non-802.11 Technology IAPP Distribution Services DS MAC DS PHY Portal Integration WM MAC WM PHY APME MLME PLME Distribution System Services: -Association -Disassociation -Distribution -Integration MAC Services: -Beacon generation -probe response/ transmission -Control frame processing -Synchronization -Retransmission -Privacy [/ Security] Station Services: -Authentication -Deauthentication -MSDU Delivery Specifically 802.11 Wireless Technology -The base 802.11 standards (core+a+b+d+g+h…) do a good job of describing (and indeed defining) the WM MAC and WM PHY. -IAPP is described in 802.11F -Distribution Services are not well described anywhere. -APME is not well described anywhere. Original Diagram Source: 11-04/540r0 The Need for an AP Functional Description Darwin Engwer and Bob O’Hara

Where Will New Services for 802.11 ESS Mesh Exist? APME IAPP Distribution Services Services to Interconnect Plurality of Mesh APs over the 802.11 WM Portal Integration DS MAC ESS Mesh Services WM MAC MLME DS PHY WM PHY PLME Quote from PAR: “The amendment will define an architecture and protocol for providing an IEEE 802.11 ESS Mesh using the IEEE 802.11 MAC to create an IEEE 802.11 Wireless Distribution System that supports both broadcast/multicast and unicast delivery at the MAC layer using radio-aware metrics over self-configuring multi-hop topologies. ” Starting with assumption that ESS Mesh will define 802.11 wireless services, but not necessarily the entire set of heterogeneous technology services that may be used in an ESS

Proposed Clarification of the Term “ESS Mesh” 802.11 ESS Mesh: a system to interconnect a set of 802.11 Mesh Access Points (APs) with peer-to-peer 802.11 wireless links supporting automatic topology learning and dynamic Layer2 path selection (possibly across multiple radio hops) for data delivery. An ESS Mesh can be used in the construction of a Distribution System (DS) and Extended Service Set (ESS). An ESS Mesh creates the wireless interconnection between Mesh APs, while a DS may be created from many different technologies including a combination of one or more ESS Mesh as well as current IEEE 802 wired LANs. Client stations (STAs) may associate with Mesh APs to gain access to the DS and ESS constructed on top of an ESS Mesh, but do not directly participate in creating the ESS Mesh infrastructure. Discussion Topic: Is this the right assumption?

Other Suggested Terminology Mesh AP: an Access Point that includes ESS Mesh functionality. Legacy AP: an Access Point that does not include ESS Mesh functionality. Mesh Link: a direct peer-to-peer 802.11 wireless link between neighboring Mesh APs. Mesh Path: a selected communication path including one or more mesh links for data forwarding between Mesh APs.

Suggested Terminology (cont.) Layer2 Mesh Routing: process by which Mesh APs select one or more path for data delivery across the set of mesh links in an ESS Mesh. Routing Metric: one or more criteria used for selecting the most appropriate data delivery path in an ESS Mesh, including, for example, link statistics such as data rate or airtime and node statistics such as queue length or congestion. Mesh Unicast: Layer2 data forwarding to a particular destination node in the ESS Mesh. Mesh Broadcast: Layer2 data forwarding to all nodes in the ESS Mesh. Mesh Multicast: Layer2 data forwarding to a subset of nodes in the ESS Mesh.

Proposed Next Steps Recommend that Mesh SG/TGs adopt a common terminology document Once adopted, participants may propose additions or modifications To be eventually integrated into TGs draft The terms listed in this presentation are a suggested starting point Interest in forming small ad-hoc group for discussions on terminology and definitions

Backup

How does IEEE 802.11 ESS Mesh fit in to the big picture? Distribution System (DS) 802.11 ESS Mesh Mesh Links 802.11 MAC/PHY (4-addr data frames) Client-to-AP Links (3-addr data frames) 802.11 BSS