1. P802.11e Hybrid coordinator and ad hoc QBSS
Month 2000
doc.: IEEE /xxx
July 2001
P802.11e Hybrid coordinator and ad hoc QBSS
Peter Johansson Congruent Software, Inc.
Peter Johansson / Congruent Software, Inc.
John Doe, His Company

2. What is QoS in an ad hoc BSS?
Month 2000
doc.: IEEE /xxx
July 2001
What is QoS in an ad hoc BSS?
There is no access point in an ad hoc BSS
Part of the HCF may exist in an ad hoc BSS
EDCF requires no hybrid coordinator
EDCF requires shared set of parameters among the participating stations
In a BSS with an AP, QoS parameters are broadcast with the beacon
P802.11e could establish default values
Fully-fledged HCF requires an HC
Peter Johansson / Congruent Software, Inc.
John Doe, His Company

3. Cleanly split AP and HC functions
July 2001
Cleanly split AP and HC functions
Access point (AP)
Authentication
Association
Distribution
From / to BSS
From / to ESS
Integration
Hybrid coordinator (HC)
Coordination
Beacon
Scheduling
Distribution
From / to BSS
Separation resolves the confusion created by the historical co-location of AP and PC functionality
Suited to AV QBSS (may not need ESS distribution)
Peter Johansson / Congruent Software, Inc.

4. Revised terminology BSS type determined by mix of capabilities
July 2001
Revised terminology
BSS type determined by mix of capabilities HC PC AP No No No
IBSS No No
Yes ? No
Yes
BSS
Yes No No
QBSS No
Yes
Stations that form a QBSS organize themselves around a hybrid coordinator
There may or may not be an AP present
What is a BSS with only an AP?
Peter Johansson / Congruent Software, Inc.

5. Current definition of QBSS
July 2001
Current definition of QBSS
P802.11e Draft 1.0 clause 3.63
“A basic service set (BSS) that supports LAN applications with quality of service (QoS) requirements by providing a QoS facility for communication via the wireless medium (WM).”
Consistent with taxonomy on previous slide
A QBSS is the set of stations under mutual control of a hybrid coordinator (HC)
… whether or not an AP is present!
Peter Johansson / Congruent Software, Inc.

6. July 2001
Contact information
Peter Johansson
Congruent Software, Inc. 98 Colorado Avenue Berkeley, CA
(510) (510) FAX
Peter Johansson / Congruent Software, Inc.