1. Uniform 802.11e Admissions Control Signaling for HCF and EDCF
doc.: IEEE /678r0
November 2002
Uniform e Admissions Control Signaling for HCF and EDCF
Bob Meier, Liwen Wu, Mark Bilstad
Cisco Systems
November 11, 2002
Bob Meier, Cisco Systems
Bob Meier, Cisco Systems

2. Considerations/Issues
doc.: IEEE /678r0
November 2002
Considerations/Issues
There is a recognized need for Explicit Admissions Control Signaling, independent of access method
Explicit EDCF Admissions Control enables infrastructure policy and policing. For example, it may be desirable to limit QoS bandwidth for “guest” users in an enterprise network.
The current TSPEC Status Codes are insufficient. A WSTA cannot determine if a TSPEC is rejected because 1) resources are not available, or 2) HCF Polling is not enabled for the traffic type.
The current draft (3.3) does not indicate whether a QSTA can use EDCF-based access for a traffic stream with an existing TSPEC.
Bob Meier, Cisco Systems
Bob Meier, Cisco Systems

3. New TSPEC Status Code Status Code Result Code Definition
doc.: IEEE /678r0
November 2002
New TSPEC Status Code
Table 20.5 – Status Codes
Status Code
Result Code
Definition 5
NOT_ENABLED
The TS has not been created because the requested access method is not enabled for the traffic type.
6-255
reserved
Bob Meier, Cisco Systems
Bob Meier, Cisco Systems

4. Add 16 bits to the TSPEC TSInfo Field in Figure 42.8
November 2002
Add 16 bits to the TSPEC TSInfo Field in Figure 42.8
Bit 16
Bit 17
Bit 18
Bits 19-20
Bits 21-31
HCF Access
EDCF Access
HCF+EDCF Access
Access Method
reserved
Table 20.1.x - Access Method field encoding
Bit 19
Bit 20
Usage
No Access Method 1
EDCF Access
HCF Access
Combined HCF and EDCF Access
Bob Meier, Cisco Systems

5. November 2002
Section
A QSTA sets the TSInfo “Access” fields in an ADDTS request to indicate to the HC the access methods that it will accept for the traffic stream and to indicate its preferred access method. The fields are set in an ADDTS Request as follows: The HCF Access field is set ON if the QSTA will accept HCF as the access method. The EDCF Access field is set ON if the QSTA will accept EDCF as the access method. The HCF+EDCF Access field is set ON if the QSTA will accept combined HCF and EDCF as the access method for an uplink traffic stream. The Access Method field in an ADDTS Request is used to indicate the access method preferred by the QSTA.
An HC uses the TSInfo Access Method field in an ADDTS Response to establish the access method used for the traffic stream for an accepted TSPEC. The HC cannot establish an access method where the QSTA has indicated that it will NOT accept the access method. The Access Method must be non-zero for an accepted TSPEC.
If HCF+EDCF is established as the access method for an uplink traffic stream, then the QSTA may use EDCF to transmit uplink frames for the traffic stream. The HC should also generate (+)CF-Poll frames for the traffic stream, as required, to mitigate contention and bound delay. The HCF+EDCF access method is useful for minimizing latency in environments with sporadic congestion. It also permits EDCF access for error recovery if an expected poll or response is not received for a polled TXOP.
Bob Meier, Cisco Systems