AP-AC communications and 802.11 Functional Architecture Month 2002 doc.: IEEE 802.11-04/xxxr0 March 2004 AP-AC communications and 802.11 Functional Architecture Michael Montemurro Chantry Networks Michael Montemurro, Chantry Networks

March 2004 Introduction CAPWAP goal is to provide interoperability between an “Access Controller” and an “Access Point” The motivation is to provide: Manageability Security Mobility Quality of Service … across “large” WLAN deployments Michael Montemurro, Chantry Networks

March 2004 What is CAPWAP really? It’s an interface between AP’s and an Access Controller. It needs to be: Robust Secure Provide functionality to make it easier to deploy and manage a wireless network Michael Montemurro, Chantry Networks

CAPWAP Architecture Definition March 2004 CAPWAP Architecture Definition Presents Four Alternative Architectures: Traditional AP Architecture with centralized management AP’s controlled centrally by Access Controller AP’s sharing 802.11 services with Access Controller Access Controller provides 802.11 MAC state – AP’s reduce to radios. Michael Montemurro, Chantry Networks

802.11 Architecture Definition March 2004 802.11 Architecture Definition 802.11 architecture defined as MAC services between STA’s Services for an AP can be: Authentication, Association, Deauthentication, Disassociation, Reassociation, Integration, MSDU Delivery Michael Montemurro, Chantry Networks

Architecture Requirements March 2004 Architecture Requirements The “service”-based architecture for 802.11 should NOT need to change to support CAPWAP The question is? Should the 802.11 standard be modified to recognize CAPWAP as a new service? Or should there be a Recommended Practice to address the a new service for CAPWAP? Michael Montemurro, Chantry Networks

What does CAPWAP need from 802.11? March 2004 What does CAPWAP need from 802.11? A component to communicate with the AC. It would be nice to have a standard interface into the 802.11 MAC Michael Montemurro, Chantry Networks

Modification to MAC for CAPWAP March 2004 Modification to MAC for CAPWAP MAC Sublayer PLCP PMD MAC Sublayer Management Entity SME CAPWAP Interface Data Link Layer Access Controller PHY Sublayer Management Entity Physical Layer New service should be defined as part of 802.11 Michael Montemurro, Chantry Networks

March 2004 IAPP and CAPWAP 802.11F was defined to support communications between Access Points IAPP defines primitives to use between Access Points: MOVE, ADD, etc. If RADIUS interaction was removed or made optional, IAPP primitives could be extended to support CAPWAP Michael Montemurro, Chantry Networks

Extend 802.11 Services Across AP’s March 2004 Extend 802.11 Services Across AP’s These primitives could be extended to address: CAPWAP communications Fast roaming RF Metrics Load-balancing information Michael Montemurro, Chantry Networks

March 2004 Conclusions Need to understand solution requirements before creating a standard solution 802.11 Architecture does not need to change to accommodate CAPWAP A new service could be defined using part of IAPP, to provide primitives to support CAPWAP, Fast Roaming, and potential future extensions Michael Montemurro, Chantry Networks