Methods and devices for multi-link contention based admission control in a wireless network
Embodiments of the present invention provide methods and devices for performing admission control in a wireless network. Admission control can be used to set usage limits for wireless devices in the network. When admission control is enabled, a wireless station does not transmit frames if the current channel usage time is greater than a predefined time limit. The admission control parameters can be specific to an access category (AC), such as best effort (BE), voice (VO), video (VI), and background (BK). According to some implementations, the admission control is performed on a link-level. According to other implementations, the admission control is performed at a multi-link device (MLD) level.
1. A method of multi-link admission control in a wireless network, the method comprising:
transmitting, by a wireless access point (AP) multi-link device (MLD), a beacon frame indicating that admission control is enabled for a wireless link of the AP MLD, wherein the AP MLD comprises a plurality of wireless links requiring admission control;
receiving, by the AP MLD, a request to add a traffic stream associated with an access category (AC) for the wireless link from a wireless station (STA) MLD;
transmitting, by the AP MLD, a response to the STA MLD, wherein the response comprises a medium access time granted for Enhanced Distributed Channel Access (EDCA) over the wireless link for the AC, wherein the STA MLD computes a total medium time allowed over the wireless link for the AC based on the medium access time granted in the response, wherein the STA MLD computes an amount of medium time used following a successful frame exchange on the wireless link; and
the AP MLD denying a subsequent request to add a traffic stream on the AC for EDCA when the amount of medium time used reaches the total medium time allowed over the wireless link for the AC, and wherein access control is performed by the AP MLD over the plurality of wireless links requiring admission control separately using different medium access time granted values.
2. The method of claim 1 , further comprising transmitting, by the AP MLD, a plurality of quality of service (QOS) frames associated with the access control category to the STA MLD, wherein the QoS frames are transmitted using EDCA over the wireless link according to the medium access time.
3. The method of claim 2 , wherein the AP MLD stops transmitting QoS frames to the STA MLD after the medium access time is expired.
4. The method of claim 1 , wherein the medium access time is carried in a traffic specification (TSPEC) element.
5. The method of claim 1 , and wherein the medium access time is applied to the plurality of links for Enhanced Distributed Channel Access (EDCA) transmission over the plurality of wireless links.
6. The method of claim 1 ,
wherein the response comprises a plurality of traffic specification (TSPEC) elements corresponding to the plurality of wireless links, and
wherein at least one of the plurality of TSPEC elements further comprises the MLD medium access time granted.
7. The method of claim 1 further comprising:
receiving, by the AP MLD, a first request to add a traffic stream associated with a first access control category for a first wireless link of the AP MLD from the STA MLD; and
transmitting, by the AP MLD, a first response to the STA MLD, wherein the first response comprises a first medium access time granted for Enhanced Distributed Channel Access (EDCA) over the first wireless link.
8. The method of claim 7 , further comprising:
receiving, by the AP MLD, a second request to add a traffic stream associated with a second access control category for a second wireless link of the AP MLD from the STA MLD; and
transmitting, by the AP MLD, a second response to the second request to the STA MLD, wherein the second response comprises a second medium access time granted for Enhanced Distributed Channel Access (EDCA) over the second wireless link.
9. The method of claim 1 , wherein the request to add a traffic stream comprises an indication of at least one of the plurality of wireless links requiring admission control.
10. The method of claim 9 , wherein the response to the request to the STA MLD comprises at least one traffic specification (TSPEC) element identifying at least one of the plurality of wireless links requiring admission control and a corresponding medium time thereof.
11. The method of claim 1 , wherein the access control category comprises at least one of: AC_VO; AC_VI; AC_BE; and AC_BK.
12. The method of claim 1 , further comprising receiving, by the AP MLD, a request to terminate the request to add a traffic stream associated with an access control category for the wireless link from the STA MLD.
13. The method of claim 12 , wherein the request to terminate the request to add a traffic stream associated with an access control category for the wireless link is carried in a delete traffic stream (DELTS) frame.
14. A method of multi-link admission control for a wireless network, the method comprising:
transmitting, by a wireless station (STA) multi-link device (MLD), a request to add a traffic stream associated with an access category (AC) for a wireless link of the STA MLD to a wireless access point (AP) MLD;
receiving, by the STA MLD, a response from the AP MLD, wherein the response comprises a medium access time granted for Enhanced Distributed Channel Access (EDCA) over the wireless link for the AC, wherein the AP MLD comprises a plurality of wireless links requiring admission control;
computing, by the STA MLD a total medium time allowed for the AC based on the medium access time granted in the response;
storing, by the STA MLD, an amount of medium time used on the wireless link; and
updating, by the STA MLD, the amount of medium time used time following a successful frame exchange on the wireless link, wherein the AP MLD is operable to deny a subsequent request to add a traffic stream on the AC for EDCA when the amount of medium time used reaches the total medium time allowed for the AC, and wherein access control is performed by the AP MLD over the plurality of wireless links requiring admission control separately using different medium access time values.
15. The method of claim 14 , further comprising receiving, by the STA MLD, a plurality of quality of service (QOS) frames associated with the access control category from the AP MLD, wherein the QoS frames are transmitted using EDCA over the wireless link according to the medium access time.
16. The method of claim 14 , wherein the AP MLD stops transmitting QoS frames to the STA MLD after the medium access time is expired.
17. The method of claim 14 , wherein the response comprises a plurality of TSPEC elements corresponding to the plurality of wireless links, and wherein at least one of the plurality of TSPEC elements comprises the medium access time.
18. The method of claim 14 , wherein the AP MLD comprises a plurality of wireless links requiring admission control, and further comprising:
receiving, by the AP MLD, a first request to add a traffic stream associated with a first access control category for a first wireless link of the AP MLD from the STA MLD;
transmitting, by the AP MLD, a first response to the STA MLD, wherein the first response comprises a first medium access time granted for Enhanced Distributed Channel Access (EDCA) over the first wireless link;
receiving, by the AP MLD, a second request to add a traffic stream associated with a second access control category for a second wireless link of the AP MLD from the STA MLD; and
transmitting, by the AP MLD, a second response to the STA MLD, wherein the second response comprises a second medium access time granted for Enhanced Distributed Channel Access (EDCA) over the second wireless link.
19. An apparatus, comprising:
a plurality of transceivers operating different wireless links;
a memory; and
a processor operable to:
transmit a beacon frame indicating that admission control is enabled for a first wireless link of a plurality of wireless links requiring admission control;
receive a request to add a traffic stream associated with an access category (AC) for the wireless link from a wireless station (STA) MLD over the wireless link;
transmit a response to the STA MLD, wherein the response comprises a medium access time granted for Enhanced Distributed Channel Access (EDCA) over the wireless link for the AC, wherein the STA MLD computes a total medium time allowed over the wireless link for the AC based on the medium access time granted in the response, wherein the STA MLD computes an amount of medium time used following a successful frame exchange on the wireless link; and
deny a subsequent request to add a traffic stream on the AC for EDCA when the amount of medium time used reaches the total medium time allowed for the AC, and wherein access control is performed over the plurality of wireless links requiring admission control separately using different medium access time values.