Avaya Inc.

At+t Corp.

AT&T Intellectual Property I, LP

Lucent Technologies Inc.

Avaya Technology LLC

At&t Wireless Services, Inc.

At&t Bell Laboratories

Interdigital Patent Holdings, Inc.

American Telephone and Telegraph, Co.

At&t Ipm Corp.

Mathilde Benveniste

Sushil Prabhu

Chunxuan Ye

Alexander Reznik

Samian Kaur

Albert Gordon Greenberg

Anjur Sundaresan Krishnakumar

John L Tomici

Mahalingam Mani

Yuying Dai

Boris Dmitrievich Lubachevsky

Frank K Hwang

Paul E Wright

Frank Kwangming Hwang

Srinivasa Rao Kocherla

Paul Emerson Wright

A method and system reduce interference between overlapping first and second wireless LAN cells in a medium. Each cell includes a respective plurality of member stations and there is at least one overlapped station occupying both cells. An inter-cell contention-free period value is assigned to a first access point station in the first cell, associated with an accessing order in the medium for member stations in the first and second cells. The access point transmits a beacon packet containing the inter-cell contention-free period value, which is intercepted at the overlapped station. The overlapped station forwards the inter-cell contention-free period value to member stations in the second cell. A second access point in the second cell can then delay transmissions by member stations in the second cell until after the inter-cell contention-free period expires.

Hybrid coordination function (HCF) access through tiered contention and overlapped wireless cell mitigation

Quality of Service (QoS) support is provided by means of a Tiered Contention Multiple Access (TCMA) distributed medium access protocol that schedules transmission of different types of traffic based on their service quality specifications. In one embodiment, a wireless station is supplied with data from a source having a lower QoS priority QoS(A), such as file transfer data. Another wireless station is supplied with data from a source having a higher QoS priority QoS(B), such as voice and video data. Each wireless station can determine the urgency class of its pending packets according to a scheduling algorithm. For example file transfer data is assigned lower urgency class and voice and video data is assigned higher urgency class. There are several urgency classes which indicate the desired ordering. Pending packets in a given urgency class are transmitted before transmitting packets of a lower urgency class.

Tiered contention multiple access (TCMA): a method for priority-based shared channel access

Hybrid coordination function (HCF) access through tired contention and overlapped wireless cell mitigation

An access point transmits a preemptive peg packet when it has no data to transmit in order to maintain the contiguity of its transmission timing position with respect to the timing position of other contention-free sessions (CFS) transmitted by other access points in an existing, periodic sequence. The cyclic prioritized multiple access (CPMA) method establishes the transmission timing position of contention-free sessions (CFS) between overlapping first and second wireless LAN cells contending for the same medium. Each cell includes a respective plurality of member stations. If an access point has no traffic, it will transmit a short, preemptive pegging packet and reset its backoff timer. In this manner, no gaps longer than the distributed coordination function (DCF) Interframe Space (DIFS) are left idle. This prevents other stations from using DCF contention to seize the channel, until all access points have completed one contention-free session (CFS) per periodic cycle.

Preemptive packet for maintaining contiguity in cyclic prioritized multiple access (CPMA) contention-free sessions

A method, apparatus and computer program product in which a computer system functions as a mesh point (MP) and provides scheduled service periods in wireless mesh networks is presented. The MP enters a light sleep mode. The MP determines peers of itself and determines beacons for the peers of itself. The MP then enters an Awake state for the beacons of its peers.

Scheduled service periods in wireless mesh networks

A method and system reduce interference between overlapping first and second wireless LAN cells contending for the same medium. Each cell includes a respective plurality of member stations. An inter-cell contention-free period value is assigned to a first access point station in the first cell, associated with an accessing order in the medium for member stations in the first and second cells. The access point in the first cell transmits an initial shield packet to deter other stations from contending for the medium. The access point then transmits a beacon packet containing the inter-cell contention-free period value to member stations in the second cell. A second access point in the second cell can then delay transmissions by member stations in the second cell until after the inter-cell contention-free period expires.

'Shield': protecting high priority channel access attempts in overlapped wireless cells

A cyclic prioritized multiple access method is disclosed which includes Fixed Deterministic Post-Backoff. Fixed deterministic post-backoff reduces conflicts between access points of overlapping cells. Contention-free sessions can be generated, one from each overlapping cell. Each active access point engages in a fixed deterministic post-backoff. A fixed deterministic backoff delay (Bkoff times a fixed number of idle time slots) is used by all access points, with the value of Bkoff being greater than the number of overlapping cells. The Bkoff should be large enough to enable the traffic that needs to be accommodated by the channel. Each access point has a backoff timer that is counted down using the shortest interframe space possible. A contention-free session is initiated when the backoff timer expires, and it is then reset to the value of Bkoff to start a new cycle.

Fixed deterministic post-backoff for cyclic prioritized multiple access (CPMA) contention-free sessions

A method, apparatus and computer program product for the express forwarding bypass are presented. A timer (NAV) is maintained at each respective node of a wireless LAN, the timer (NAV) set to a corresponding time period during which the respective node must refrain from transmitting on a channel. The first node of said plurality of nodes has a time-critical (TC) frame. The first node detects a frame to be express-forwarded by a second node. The first node decrements the duration field by a first predetermined time increment (DT) before setting its NAV. The first node attempts transmission of the TC frame or back off countdown when the NAV of said first node expires.

Method and apparatus performing express forwarding bypass for time-critical frames

A method and apparatus for maintaining a connection between a wireless transmit/receive unit (WTRU) and a blanket wireless local area network (BWLAN) are described. An inter-working function (IWF) entity in a given network access point (NAP) of the BWLAN maintains lists of WTRUs in respective states. Furthermore, the given NAP maintains a list of neighbor NAPs, and operates in accordance with a selected WTRU mobility protocol. The states may include a 'not aware' (NA) state in which the given NAP is actually not aware of a particular WTRU, an 'active transmit' (AT) state in which the given NAP is actively transmitting to a particular WTRU, and a &#x201c;neighbor range&#x201d; (NR) state for WTRUs indicated in an update report from neighbor (URN) message that the given NAP was not aware of. The WTRU mobility protocol may be a push mobility protocol or a poll mobility protocol.

Method and apparatus for implementing a blanket wireless local area network control plane

Growing community of inventors

South Orange, NJ, United States of America

Mathilde Benveniste