1. doc.: IEEE 802.11-04/595r2 Submission May 2002 Lily Yang, Tyan-Shu JouSlide 1 Mesh Relevance in CAPWAP and AP Functional Descriptions L. Lily Yang (Intel Corp.) Tyan-Shu Jou (Janusys Networks) lily.l.yang@intel.com tsjou@janusysnetworks.com

2. doc.: IEEE 802.11-04/595r2 Submission May 2002 Lily Yang, Tyan-Shu JouSlide 2 Overview Intro to IETF CAPWAP –The role of mesh in CAPWAP –Need help from mesh vendors The need for “AP Functional Descriptions” –Why? –Benefits (to mesh group and others) –Need a new SG References

3. doc.: IEEE 802.11-04/595r2 Submission May 2002 Lily Yang, Tyan-Shu JouSlide 3 IETF CAPWAP Problem Statement Network administration burden: –Management –Monitoring –Control Effective RF dynamic provisioning: needs coordination among APs Maintaining Consistent Configuration Security: –Access to the network (e.g., physical security of APs) –Rogue AP detection

4. doc.: IEEE 802.11-04/595r2 Submission May 2002 Lily Yang, Tyan-Shu JouSlide 4 CAPWAP Architecture Taxonomy Autonomous Architecture Centralized Architecture Distributed Architecture 802.11 WLAN Architectures * Centralized controller * Distributed control across multiple nodes * Self-contained controller Categorized by Control Plane Characteristics

5. doc.: IEEE 802.11-04/595r2 Submission May 2002 Lily Yang, Tyan-Shu JouSlide 5 From Autonomous to Centralized Local MAC Split MAC Remote MAC AP Functionality WTPAC Real Time MACPHYNon RT MACControl & Config Autonomous WTP MACPHY Control & Config AC WTP MACPHYControl & Config WTP AC Real Time MACPHYNon RT MACControl & Config

6. doc.: IEEE 802.11-04/595r2 Submission May 2002 Lily Yang, Tyan-Shu JouSlide 6 What about Mesh? Data plane: de-centralized, multi-hop Control plane: can be either [2] –Centralized, or –Distributed, or –Hybrid CAPWAP may offer a solution for control and management in mesh networks STA 1STA2 AP #1 STA 3STA 4 AP #3 External Network AP #2 STA 5 ACPortal

7. doc.: IEEE 802.11-04/595r2 Submission May 2002 Lily Yang, Tyan-Shu JouSlide 7 Help needed from mesh vendors CAPWAP mailing list: http://www.ietf.org/html.charters/capwap-charter.html Current taxonomy document: –http://www.ietf.org/internet-drafts/draft-ietf-capwap- arch-02.txt –Need help from mesh vendors on distributed control –Timeline: next 2-3 weeks for another revision Possibly WG last call by end of June Encourage everyone to participate

8. doc.: IEEE 802.11-04/595r2 Submission May 2002 Lily Yang, Tyan-Shu JouSlide 8 “AP Functional Descriptions”: What? [5] To describe the AP architecture and functionality standardized by the current standard and its amendments, or implied by them. The purpose is to provide a better informative description of an AP, to provide: –the basis for interoperability by design (rather than by test), –technical innovation, and –alignment with the work of other groups.

9. doc.: IEEE 802.11-04/595r2 Submission May 2002 Lily Yang, Tyan-Shu JouSlide 9 Trends (Why?) [5] A trend in 802.11 WG: –from “link view” to “wireless network view” –i.e. from 11e, 11n ==> 11r, 11s, WNM, WIEN Natural evolution for WLAN architectures –From one-box AP with BSS-centric view (“Autonomous Architecture”) –To better coordinated inter-BSS services: “Distributed Architecture”: distributed coordination by peer nodes (example: mesh) “Centralized Architecture”: centralized controller for the network Original AP definitions: interaction with the DS is vague –No interoperability within ESS Need to provide better descriptions of ESS and interoperability within the ESS

10. doc.: IEEE 802.11-04/595r2 Submission May 2002 Lily Yang, Tyan-Shu JouSlide 10 What Groups can Benefit from This? [5] To provide a formal description of the 802.11 AP for use by other groups. –802.1X also needed and needs a clean description of the functions and behaviors of an AP. –CAPWAP: The AP functional descriptions can be used by the IETF CAPWAP group. –802.11 TGs (ESS Mesh) will extend the functions of an AP to provide for operation in a mesh of APs. This again requires a clear description of the baseline functions of an AP as a starting point. –802.21 will be specifying inter-802 mobility (e.g. 802.11 to 802.15, and 802.11 to 802.3), and also 802 to cellular mobility. These efforts also require a core functional description of an 802.11 AP.

11. doc.: IEEE 802.11-04/595r2 Submission May 2002 Lily Yang, Tyan-Shu JouSlide 11 Need to form a new SG [5] To work on better “AP Functional Descriptions” Some open questions for SG to investigate –What do we have today in the Standards (as starting points)? –What is missing, lacking, or confusing? –How to approach the functional decomposition (methodology, granularity)? –How to describe the interface or interaction? –How to better separate data plane and control plane? –What kind of documents will be produced in the end? –What impact does it have on other 802.11 groups? Current discussions in ESS Mesh touch some of these questions, but mostly around mesh and for mesh. => A new SG is needed to address these general issues.

12. doc.: IEEE 802.11-04/595r2 Submission May 2002 Lily Yang, Tyan-Shu JouSlide 12 IAPP Distribution Services DS MAC DS PHY PortalIntegration WM MAC WM PHY APME MLME PLME One Possible Starting Point based on IAPP Diagram [4] Mesh Relevance: First need to figure out the baseline AP functions, and then figure out where/what ESS mesh functions are …

13. doc.: IEEE 802.11-04/595r2 Submission May 2002 Lily Yang, Tyan-Shu JouSlide 13 ESS Mesh Group can also help AP Functional Descriptions A lot of the questions about AP, DS, DSS, ESS are being asked here by ESS mesh group  Indication of the need to re-examine the current descriptions  Better understanding can result from the discussion here  Can potentially feedback to the new SG/TG

14. doc.: IEEE 802.11-04/595r2 Submission May 2002 Lily Yang, Tyan-Shu JouSlide 14 Summary Encourage mesh vendors here to participate in IETF CAPWAP and contribute to the discussion of Distributed Architecture Encourage ESS Mesh Group to stay informed of the CFI on AP Functional Descriptions in WNG and contribute to the effort

15. doc.: IEEE 802.11-04/595r2 Submission May 2002 Lily Yang, Tyan-Shu JouSlide 15 References For additional information, please refer to these more detailed submissions: –[1] 11-04-0544-00-0wng-ap-functional-needs-capwap.ppt –[2] 11-04-0527-00-0wng-wlan-mesh-in-capwap-architecture.ppt –[3] 11-04-0481-03-0wng-thoughts-on-ap-functional-descriptions.ppt –[4] 11-04-0540-00-0wng-need-ap-functional-descriptions.ppt –[5] 11-04-0604-00-0wng-ap-functional-descriptions-update.ppt