EP4026378A1

EP4026378A1 - Medium usage in multi-access node environment

Info

Publication number: EP4026378A1
Application number: EP19769963.0A
Authority: EP
Inventors: Olli Alanen; Enrico Henrik Rantala; Mika Kasslin; Janne Marin; Veli-Matti KOLMONEN
Original assignee: Nokia Technologies Oy
Current assignee: Nokia Technologies Oy
Priority date: 2019-09-04
Filing date: 2019-09-04
Publication date: 2022-07-13
Also published as: WO2021045737A1

Abstract

Solution for controlling wireless medium usage in a wireless network system. According to an aspect, a method comprises as performed by a master node (110) of a wireless network: receiving, a first message from a first access node (112), wherein the first message comprises a first association information; receiving, by the apparatus a second message from a second access node (114), wherein the second message comprises a second association information, wherein the first/second association information is based on a number of wireless devices associated with the first/second access node; determining, by the apparatus, at least channel occupancy information indicating (306) at least partly a first maximum channel occupancy duration, wherein the channel occupancy information is based at least partly on the first association information and on the second association information; and transmitting, by the apparatus, the channel occupancy information to the first access node (112).

Description

MEDIUM USAGE IN MULTI ACCESS NODE ENVIRONMENT

Field

Various embodiments described herein relate to the field of wireless communications and, particularly, to usage of a wireless medium in an environment comprising plurality of access nodes.

Background

There is a constant demand of higher throughput and capacity for wireless networks. One cause for this demand is that number of wireless devices in increasing all the time in many spaces. One option to improve scalability is to utilize multiple access nodes within a space.

If the multiple access nodes are operated by same operator or entity, it may be beneficial to have at least a gateway via which the multiple access nodes interface with external networks, like internet. The gateway or other network entity may also comprise a controlling function to ease management of the multiple access nodes.

Local network system comprising the multiple access nodes and the gateway may have two kind of links: access links, i.e. links between wireless terminals and access nodes, and backhaul links, i.e. links between access nodes and the gateway.

Brief description

Some aspects of the invention are defined by the independent claims.

Some embodiments of the invention are defined in the dependent claims.

Some example aspects and embodiments are listed in the Brief description of the invention -section. The aspects and embodiments that do not fall under the scope of the claims are to be interpreted as examples useful for understanding the disclosure.

According to an aspect, there is provided an apparatus for a wireless network, comprising means for performing: receiving a first message from a first access node, wherein the first message comprises a first association information, wherein the first association information is based on a number of wireless devices associated with the first access node; receiving a second message from a second access node, wherein the second message comprises a second association information, wherein the second association information is based on a number of wireless devices associated with the second access node; determining at least channel occupancy information indicating at least partly a first maximum channel occupancy duration, wherein the channel occupancy information is based at least partly on the first association information and on the second association information; transmitting the channel occupancy information to the first access node.

In an embodiment, said determining at least the channel occupancy information comprises determining another channel occupancy information indicating at least partly a second maximum channel occupancy duration, different from the first maximum channel occupancy duration, wherein the another channel occupancy information is based at least partly on the first association information and on the second association information, and wherein the apparatus further comprises means for transmitting the another channel occupancy information to the second access node.

In an embodiment, the channel occupancy information is at least partly proportional to the first association information.

In an embodiment, the another channel occupancy information is at least partly proportional to the second association information.

In an embodiment, the channel occupancy information indicates at least partly a second maximum channel occupancy duration, and wherein the apparatus further comprises means for transmitting the channel occupancy information to the second access node.

In an embodiment, the first maximum channel occupancy duration is based at least partly on the first association information and on the channel occupancy information and wherein the second maximum channel occupancy duration is based at least partly on the second association information and on the channel occupancy information.

In an embodiment, the channel occupancy information is based at least partly on the sum of the first association information and the second association information.

In an embodiment, the first association information comprises a number of the wireless devices associated with the first access node and the second association information comprises a number of the wireless devices associated with the second access node.

In an embodiment, the first maximum channel occupancy duration is proportional to the first association information.

In an embodiment, the second maximum channel occupancy duration is proportional to the second association information.

In an embodiment, the first maximum channel occupancy duration is a transmission opportunity limit.

In an embodiment, the channel occupancy information indicates a plurality of transmission opportunity limits, wherein at least part of the plurality of transmission opportunity limits are per access category.

In an embodiment, the apparatus is a gateway node providing access to an external network.

In an embodiment, the apparatus comprises at least a control node.

In an embodiment, the first access node is an access point of a first wireless local area network and the second access node is an access point of a second wireless local area network and the wireless devices associated with the first access node and the wireless devices associated with the second access node are stations. In an embodiment, the apparatus is an access point in the wireless network, the first access node is a station of the wireless network and the second access node is another station in the wireless network.

In an embodiment, said transmitting the channel occupancy information to the first access node comprises transmitting the channel occupancy information to the first access node on a frequency channel, and wherein the channel occupancy information indicates a maximum time the first access node may continuously occupy the frequency channel.

In an embodiment, the first message is an access point metrics response message.

According to an aspect, there is provided an apparatus for a wireless network, comprising means for causing an access node to perform: transmitting a first message on a channel to a master node, wherein the first message comprises a first association information, wherein the first association information is based on a number of wireless devices associated with the access node; receiving, on the channel from the master node, a channel occupancy information, indicating at least partly a maximum channel occupancy duration, wherein the channel occupancy information is based at least partly on the first association information and on a second association information, wherein the second association information is based on a number of wireless devices associated with a second access node; operating on the channel according to the channel occupancy information.

In an embodiment, communications between the access node and the wireless devices associated with the access node are performed on another channel.

In an embodiment, the first association information comprises a number of the wireless devices associated with the access node.

In an embodiment, the maximum channel occupancy duration is a transmission opportunity limit.

In an embodiment, the access node is an access point of a wireless local area network and the master node is a gateway node providing access to an external network

In an embodiment, the channel is a frequency channel.

In an embodiment, the means comprises: at least one processor; and at least one memory including comprising computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the performance of the apparatus.

According to an aspect, there is provided a method for an apparatus for a wireless network, comprising: receiving, by an apparatus for a wireless network, a first message from a first access node, wherein the first message comprises a first association information, wherein the first association information is based on a number of wireless devices associated with the first access node; receiving, by the apparatus a second message from a second access node, wherein the second message comprises a second association information, wherein the second association information is based on a number of wireless devices associated with the second access node; determining, by the apparatus, at least channel occupancy information indicating at least partly a first maximum channel occupancy duration, wherein the channel occupancy information is based at least partly on the first association information and on the second association information; transmitting, by the apparatus, the channel occupancy information to the first access node.

In an embodiment, said determining at least the channel occupancy information comprises determining another channel occupancy information indicating at least partly a second maximum channel occupancy duration, different from the first maximum channel occupancy duration, wherein the another channel occupancy information is based at least partly on the first association information and on the second association information, and wherein the method further comprises transmitting the another channel occupancy information to the second access node.

In an embodiment, the channel occupancy information indicates at least partly a second maximum channel occupancy duration, and wherein the further comprises transmitting the channel occupancy information to the second access node.

In an embodiment, the apparatus comprises at least a control node. In an embodiment, the first access node is an access point of a first wireless local area network and the second access node is an access point of a second wireless local area network and the wireless devices associated with the first access node and the wireless devices associated with the second access node are stations.

In an embodiment, the apparatus is an access point in the wireless network, the first access node is a station of the wireless network and the second access node is another station in the wireless network.

In an aspect, there is provided a method comprising: transmitting, by an apparatus for a wireless network, a first message on a channel to a master node, wherein the first message comprises a first association information, wherein the first association information is based on a number of wireless devices associated with the access node; receiving, by the apparatus on the channel from the master node, a channel occupancy information, indicating at least partly a maximum channel occupancy duration, wherein the channel occupancy information is based at least partly on the first association information and on a second association information, wherein the second association information is based on a number of wireless devices associated with a second access node; operating, by the apparatus, on the channel according to the channel occupancy information.

According to an aspect, there is provided a computer program product embodied on a computer-readable medium and comprising a computer program code readable by a computer for an apparatus of a first wireless network, wherein the computer program code configures the computer to carry out a computer process comprising: receiving a first message from a first access node, wherein the first message comprises a first association information, wherein the first association information is based on a number of wireless devices associated with the first access node; receiving a second message from a second access node, wherein the second message comprises a second association information, wherein the second association information is based on a number of wireless devices associated with the second access node; determining at least channel occupancy information indicating at least partly a first maximum channel occupancy duration, wherein the channel occupancy information is based at least partly on the first association information and on the second association information; transmitting the channel occupancy information to the first access node.

According to an aspect, there is provided a computer program product embodied on a computer-readable medium and comprising a computer program code readable by a computer for an apparatus of a first wireless network, wherein the computer program code configures the computer to carry out a computer process comprising: transmitting a first message on a channel to a master node, wherein the first message comprises a first association information, wherein the first association information is based on a number of wireless devices associated with the access node; receiving, on the channel from the master node, a channel occupancy information, indicating at least partly a maximum channel occupancy duration, wherein the channel occupancy information is based at least partly on the first association information and on a second association information, wherein the second association information is based on a number of wireless devices associated with a second access node; operating on the channel according to the channel occupancy information.

List of drawings

Embodiments are described below, by way of example only, with reference to the accompanying drawings, in which

Figures 1 to 2 illustrate wireless communication scenarios to which some embodiments of the invention may be applied;

Figure 3 illustrates a signalling diagram according to one or more embodiments employing controlling wireless medium usage;

Figure 4 illustrates usage of frequency bands/channels according to one or more embodiments employing controlling wireless medium usage;

Figures 5 to 6 illustrate some embodiments of processes for controlling wireless medium usage;

Figure 7 illustrate some embodiments of channel occupation times in a shared wires medium;

Figures 8 and 9 illustrate block diagrams of structures of apparatuses according to some embodiments of the invention;

Figure 10 illustrates a signalling diagram according to one or more embodiments employing controlling wireless medium usage.

Description of embodiments

The following embodiments are examples. Although the specification may refer to “an”, “one”, or “some” embodiment(s) in several locations, this does not necessarily mean that each such reference is to the same embodiment(s), or that the feature only applies to a single embodiment. Single features of different embodiments may also be combined to provide other embodiments. Furthermore, words “comprising” and “including” should be understood as not limiting the described embodiments to consist of only those features that have been mentioned and such embodiments may contain also features/structures that have not been specifically mentioned.

A general wireless communication scenario to which embodiments of the invention may be applied is illustrated in Figure 1. Figure 1 illustrates wireless communication devices comprising a plurality of access nodes (AN) or access points (AP) 112 to 114 and a plurality of wireless devices or stations (STA) 100 to 108. An access node is a general term for an apparatus managing a wireless network and providing the STAs with wireless services. For simplicity, many embodiments below refer to AP, but the word “AP” in those embodiments may be replaced with “access node”. Similarly, “STA” may be replaced with “wireless device”.

Figure 1 further comprises a master node (MN) 110. The master node may serve as gateway and provide access to external networks 120 for client nodes, such as the access nodes 112, 114. Thus, the access nodes 112, 114 does not need to have their own direct interfaces towards external networks, but they may provide their STAs access to external networks 120, e.g. the Internet, via the MN 110. The access nodes 112, 114 may be associated with the MN 110. The MN 110 may comprise a controller for managing the access nodes 112, 114 and/or wireless networks managed by the access nodes 112, 114. In an embodiment, STAs, e.g. STA 108, may directly associate with the MN 110 or an access node entity of it. In another embodiment, STAs 102 to 108 may not associate directly to the MN 110. In an embodiment, the access nodes 112, 114 may be called beacon devices. These associations will be clarified later in more detail.

The access node may be an AP. Each AP may be associated with a basic service set (BSS) which is a basic building block of an IEEE 802.11 wireless local area network (WLAN). The most common BSS type is an infrastructure BSS that includes a single AP together with all STAs associated with the AP. The AP may be a fixed AP or it may be a mobile AP. The APs 112, 114 may also provide access to other networks, e.g. the Internet. In another embodiment, the BSS may comprise a plurality of APs to form an extended service set (ESS), e.g. the APs 112, 114 may belong to the same ESS with another AP and have the same service set identifier (SSID). While most embodiments of the invention are described in the context of IEEE 802.11 based networks, it should be appreciated that these or other embodiments of the invention may be applicable to networks based on other specifications, e.g. different versions of the IEEE 802.11, 3GPP Long Term Evolution (LTE), 3GPP New Radio (NR), and other networks having cognitive radio features, e.g. transmission medium sensing features and adaptiveness to coexist with radio access networks based on different specifications and/or standards.

IEEE 802.11 specifications specify a data transmission mode that includes a primary channel and secondary channels. The primary channel is used in all data transmissions and, in addition to the primary channel, one or more secondary channels may be employed for additional bandwidth. The transmission band of a BSS may contain the primary channel and zero or more secondary channels. The secondary channels may be used to increase data transfer capacity of a transmission opportunity (TXOP). The secondary channels may be called a secondary channel, a tertiary channel, a quaternary channel, etc. However, let us for the sake of simplicity use the secondary channel as the common term to refer also to the tertiary or quaternary channel, etc. The primary channel is a common channel of operation for all ST As that are members of the BSS. The primary channel may be used for channel contention, and a TXOP may be gained after successful channel contention on the primary channel. The primary channels and the secondary channels may be frequency channels.

Some IEEE 802.11 networks employ channel contention based on carrier sense multiple access with collision avoidance (CSMA/CA) for channel access. Every device attempting to gain a TXOP is reducing a backoff value while the primary channel is sensed to be idle for a certain time interval. The backoff value may be selected randomly within a range defined by a contention window parameter. The contention window may have different ranges for different types of traffic, thus affecting priority of the different types of traffic. The channel sensing may be based on sensing a level of radio energy in the radio channel. The sensed level may be compared with a threshold: if the sensed level is below the threshold level, the channel may be determined to be idle (otherwise busy). Such a procedure is called clear channel assessment (CCA) in 802.11 specifications. When the backoff value reaches zero, the STA gains the TXOP and starts frame transmission. If another STA gains the TXOP before that, the backoff value computation may be suspended, and the STA continues the backoff computation after the TXOP of the other STA has ended and the primary channel is sensed to be idle. The time duration (the backoff value) may not be decremented during the TXOP of the other STA, but the time duration that already lapsed before the suspension may be maintained, which means that the device now has a higher probability of gaining the TXOP. A secondary channel may be used in the transmission if it has been free for a determined time period (may be the same or different time period than that used for gaining the TXOP) just before TXOP start time in order for the contending device to take the secondary channel in use.

The above-mentioned transmission opportunity, TXOP, may be defined as an interval of time during which a particular station has the right to initiate frame exchange sequences onto a wireless medium (WM). The TXOP may be defined by a starting time and a maximum duration. The particular station may be quality-of-service (QOS) station. The particular station may obtain the TXOP by winning channel contention as discussed above and/or as specified in IEEE 802.11 specifications. The wireless medium may be used to transfer protocol data units (PDUs), e.g. between peer physical layer (PHY) entities of a wireless local area network.

The wireless medium may be called a channel. The channel may comprise one or more frequency channels. The channel may be a frequency channel. The channel may comprise a frequency band defined by a center frequency and a bandwidth. The bandwidth may be indicated in megahertz (MHz). The bandwidth may be 20 MHz or multiple of that, as an example. Channel contention to obtain a TXOP may be performed on one or more frequency channels. Channel contention may be performed only on a frequency channel, e.g. on the primary channel of the BSS.

Wireless networks other than WLAN may comprise similar features as mentioned above or later in this document. For example, in LTE and/or in NR-based systems, wireless devices may acquire the channel and/or contend for channel access by using Listen-Before -Talk (LBT) operation. In general, LBT is a procedure wherein radio transmitters sense a medium and transmit only if the medium is sensed to be idle. With LBT, LTE/NR systems may share an unlicensed band with WLAN systems. Therefore, as mentioned earlier, many embodiments described here in the context of WLAN may be applied also to LTE, NR, or other radio systems in which wireless devices also contend for channel access. There may be differencies between collision avoidance mechanisms implemented in these different systems.

The STA 100 to 108 may be a terminal device or a station capable of connecting to or associating with any one of the APs 112, 114. The STA may establish a connection with any one of APs it has detected to provide a wireless connection within the neighbourhood of the STA. The connection establishment may include authentication in which an identity of the STA is established in the AP. The authentication may comprise setting up an encryption key used in the BSS. After the authentication, the AP and the STA may carry out association in which the STA is fully registered in the BSS, e.g. by providing the STA with an association identifier (AID). A separate user authentication may follow association, which may also comprise building an encryption key used in the BSS. It should be noted that in other systems terms authentication and association are not necessarily used and, therefore, the association of the STA to an AP should be understood broadly as establishing a connection between the STA and the AP such that the STA is in a connected state with respect to the AP and waiting for downlink frame transmissions from the AP and monitoring its own buffers for uplink frame transmissions. A STA not associated to the AP is in an unassociated state. An unassociated STA may still exchange some frames with the AP, e.g. discovery frames.

For the sake of the following description, let us assume a situation where the STAs 100 and 104 are associated to the access node or AP 112 while the STA 106 is associated to the access node or AP 114. Further, the APs 112, 114 manage different wireless networks 130, 132, which may have different network identifiers, e.g. different SSIDs. Coverage areas of the respected networks may be either distinct or at least partially overlapping. The channels of the wireless networks 130, 132 may be either same or different. The MN 110 may comprise an AP entity managing a wireless network 140. This may be called a wireless backhaul network. It may be a wireless local area network. The APs 112 and 114 are associated to the MN 110 and/or its AP entity. This may be implemented so that the APs or devices 112 and 114 have two entities or functions which may have separate wireless interfaces: AP entity and STA entity. In other words, AP entity of the device 112 may manage the wireless network 130 while the STA entity of the device 112 may associate to the wireless network 140 managed by the MN 110. A channel of the wireless network 140 may be different from a channel of at least one wireless network 130, 132. For example, a channel #1, e.g. a primary channel, of the wireless network 140 may be different from a channel #2 of the wireless network 130. The channels #1 and #2 may be non-overlapping. In addition to the wireless network 140, the MN 110 may manage a wireless network 134 to which non-AP STAs may associate with.

Figure 2 illustrates an embodiment related to the wireless communication scenario of Figure 1. In this embodiment, the MN 110 is a multi-access point (multi-AP, MAP) device 200. The MAP device 200 may comprise a MAP controller and one or more APs 202. The MAP device 200 may be connected to a plurality of MAP devices 210, 220. The MAP devices 210, 220 may be associated with the MAP device 200. The MAP devices 210, 220 may comprise backhaul STAs 211, 221, which may associate with the AP 202. The AP 202 may be called backhaul AP. The links between the backhaul STAs 211 , 221 and the AP 202 may be called backhaul links. The MAP devices 210, 220 may comprise MAP agents 212, 222. The MAP devices 210, 220 may comprise APs 213, 223, which may be called fronthaul APs. Wireless devices or STAs, such as STAs 100 to 108, may associate with the APs 213, 223. The links between the STAs 100 to 108 and the APs 213, 223 may be called fronthaul links or access links. Each MAP device may comprise zero or more APs. In an embodiment, the MAP device 200 may also comprise a MAP agent serving one or more APs.

The MAP controller may control operation of a multi-AP network comprising at least the MAP devices 200, 210, 220. The multi-AP network may be a Wi-Fi network or a combination of Wi-Fi networks. The MAP agent 212, 222 may execute AP control functions and provide multi- AP specific control information to the MAP controller 201. The MAP controller 201 may receive measurements and capability data for fronthaul APs 213, 223, stations and backhaul links from the MAP agents 212, 222, and may trigger AP control related commands and operations on the MAP Agents 212, 222. In an embodiment, the MAP controller may send an AP metrics query message to one or more MAP agents, and in response receive an AP metrics response message from at least one of the one or more MAP agents. The AP metrics response message or another message transmitted from MAP agent to MAP controller may comprise total number of STAs currently associated with a BSS. This information may be provided per wireless network, e.g. BSS, or per access node, in case the MAP agent manages a plurality of wireless networks 130, 132, and/or APs. Based on e.g. this information, the MAP controller may perform above mentioned control operation. For example, the MAP controller 201 may mandate the MAP agent 212 to steer one or more STAs associate to the AP 213 to another AP. In another embodiment, control information received from one or more MAP agents may be used by the MAP controller to request at least an AP to switch channel, change bandwidth, and/or change transmission power.

The multi-AP devices 200, 210, 220, the multi-AP controller 201, and the multi-AP agents 212, 222 may further comprise features specified in Wi-Fi Alliance Multi-AP Specification, version 1.0 or some future version. As already mentioned, when describing embodiments related to the scenarios illustrated in Figures 1 and 2, the APs 112 and 114 may associate to the wireless network 140 managed by the MN 110. An embodiment of this is where the backhaul STA 211 of MAP device 210 and the backhaul STA 221 of MAP device 220 associate with the wireless network, e.g. 140, managed by the AP 202. If traditional channel contention, e.g. based on CSMA/CA, is applied, the devices 112, 114 may share the channel of the wireless network 140 evenly. In other words, if the devices 112, 114 both have significant amount of uplink data to transmit, originated from STAs 100-106, they may occupy the channel evenly, i.e. the total time device 112 has occupied the channel during a time period is statistically equal or close to the total time device 114 has occupied the channel during the time period. The time period may be, for example, 100ms, Is, lmin, or lh. Since a path from STA to MN 110 comprise both backhaul link and fronthaul link, the capacity of the backhaul links is then further divided to the STAs 100-104 associated to the device 112 and to the station 106 associated to the device 114, causing the station 106 to obtain about 50% of the total available uplink time of the channel of the wireless network 140, and each of the STAs 100-104 to obtain about 17% of this total available uplink time. From end user perspective, and also from network management viewpoint, this may be considered unfair. In this scenario it is assumed that the APs 112, 114 use different radio for backhaul and fronthaul/access links. The following table clarifies above numerical example.

Figure 3 illustrates a signalling diagram according one or more embodiments for controlling wireless medium usage in a multi-AP deployment. First, STAs 100-104 may associate to the access node or AP 112 in step 301 and the STA 106 may associate to the access node or AP 114 in step 302. Even though Figure 3 shows that step 301 occurs between before step 302, these association establishments may occur at any order. For example, STAs 100, 102, may first associate to the AP 112, then STA 106 may associate to the AP 114, and finally STA 104 may associate to the AP 112. Establishing these associations may comprise each STA transmitting an association/reassociation request to an AP and in response receiving an association/reassociation response from the AP. After establishing associations, the APs 112, 114 may transmit messages 303, 304 to the MN 110. The message 303 may comprise a first association information on wireless devices associated with the AP 112, and the message 304 may comprise a second association information on wireless devices associated with the AP 114.

Then, the MN 110 may in step 305 determine a first channel occupancy information indicating at least partly a first maximum channel occupancy duration and a second channel occupancy information indicating at least partly a second maximum channel occupancy duration. The determining may be based at least partly on the first association information and the second association information, e.g. on the sum of the first association information and the second association information. After the determining, the MN 110 may transmit a message 306 comprising the first channel occupancy information to the AP 112 and a message 307 comprising the second channel occupancy information to the AP 114. After receiving the messages 306, 307, the APs 112, 114 shall apply the received information when occupying the channel, steps 308, 309. The messages may be frames, e.g. IEEE 802.11 frames.

In another embodiment, the MN 110 may in step 305 determine a channel occupancy information indicating at least partly a first maximum channel occupancy duration and a second maximum channel occupancy duration, wherein the determining is based at least partly on the first association information and the second association information, e.g. on the sum of the first association information and the second association information.. After the determining, the MN 110 may transmit a message 306 comprising the channel occupancy information to the AP 112 and a message 307 comprising the channel occupancy information to the AP 114. In an embodiment, the channel occupancy information may be transmitted in a broadcast or multicast frame, such as beacon frame, instead or in addition to transmitting the channel occupancy information in the messages 306, 307. After receiving the messages 306, or the broadcast/multicast frame, the AP 112 may in step 308 first determine the first maximum channel occupancy duration. The first maximum channel occupancy duration may be based at least partly on the first association information and on the channel occupancy information. The first maximum channel occupancy duration may be based at least partly on the number of the ST As associated to the AP 112 and on the channel occupancy information. For example, the first maximum channel occupancy duration may be a product of the channel occupancy information and the number of wireless devices associated with the AP 112. The first maximum channel occupancy duration may be inversely proportional to the channel occupancy information and directly proportional to the number of wireless devices associated with the AP 112.The AP 114 may then apply the first maximum channel occupancy duration when occupying the channel. The AP 114 may perform correspondingly in step 309.

The first association information may be based on a number of the wireless devices associated with the AP 112 and the second association information may be based on a number of the wireless devices associated with the AP 114. The first association information may comprise a number of the wireless devices associated with the AP 112 and the second association information may comprise a number of the wireless devices associated with the AP 114. In an embodiment, association information and/or number may indicate a range of associated STAs, e.g. value “1” may indicate that there are 1-2 associated STAs, value “2” may indicate that there are 3-10 associated STAs, and value “3” may indicate that there are over 10 associated STAs. These are just examples of what association information may comprise. In various embodiments it may indicate number, amount, range, and/or magnitude of number of STAs associated with the corresponding AP. The association information may be weighted, i.e. APs may take priority of associated STAs into account. The priorities may be based on e.g. user priority or access class. The following table illustrates an example of the weighted association information (WAI), or weighted number of associated STAs.

In an embodiment, the MN 110 may determine the first channel occupancy information so that it is at least partially proportional to the first association information. Further, the first channel occupancy information may be inversely proportional to the sum of association information values received from all or part of APs 112, 114 associated to the MN 110. In an example of Figure 3, the first channel occupancy information may be inversely proportional to the sum of the first association information and the second association information. The second channel occupancy information may be determined correspondingly. In an embodiment wherein the association information comprises (non-weighted) number of associated STAs, the AP 112 shall set the first association information in the message 303 to value 3, since 3 STAs are associated to the AP 112, and the AP 114 shall set the second association information in the message 304 to 1. Then, the first channel occupancy information may be proportional to 3, and the second channel occupancy information may be proportional to 1. Both the first channel occupancy information and the second wireless occupancy information may be proportional to ¼.

The first maximum channel occupancy duration may be proportional to the first association information and/or to the number of wireless devices associated with the AP 112. The second maximum channel occupancy duration may be proportional to the second association information and/or to the number of wireless devices associated with the AP 114. The first maximum channel occupancy duration may be a first TXOP limit and the second first maximum channel occupancy duration may be a second TXOP limit.

In an embodiment, the first channel occupancy information may be or may indicate a first TXOP limit and the second channel occupancy information may be or may indicate a second TXOP limit. TXOP limit may be defined as maximum duration of a single TXOP. There may be separate TXOP limits per access category (AC). Thus, the first TXOP limit, and the second TXOP limit respectively, may refer to either a single TXOP limit or to a set of TXOP limits comprising the separate TXOP limits. In another embodiment, the (first/second) channel occupancy information may indicate maximum total duration of TXOPs which may be obtained during a specified time period. The specified time period may be signalled to the APs in messages 306, 307 or in beacon frame.

In an embodiment, the messages 306, 307 may be separate messages. In another embodiment, the message 306 and the message 307 are the same, in which case it may be broadcasted or groupcasted to a group of associated STAs. The group may comprise all or subset of the associated STAs, e.g. APs 112, 114. In an embodiment, the message 303, 304 may be AP metric response message, referred in text related to Figure 2. In an embodiment, the AP 112 may transmit the message 303 to the MN 110 when the number of ST As associated with the AP 112 changes. The AP 114 may operate respectively. The APs 112, 114 may transmit these messages only periodically. The MN 110 may re -determine (first/second) channel occupancy information after receiving the message(s) 303 and/or 304 and/or periodically. After this, the steps 306-309 are performed as discussed earlier.

Figure 10 illustrates an embodiment, wherein the AN 112 may serve another AN 116 (not shown in Figure 1), i.e. the AN 112 may relay messages between the AN 116 and the MN 110. The AN 112 and the AN 116 may be MAP devices 210, 220 (Figure 2). In an embodiment, a backhaul STA of the AN 116 may associate with a fronthaul AP of the AN 112. As in Figure 3, STAs 100-104 may associate with the AN 112 (step 301). One or more STAs 108 may associate with the AN 116 (step 1001). The AN 116 may send a message to the AN 112, indicating number of STAs associated with the AN 116 (step 1002). Since traffic originated from STA(s) 108 also uses the link between AN 112 and the MN 110, the message 303 may comprise information on STAs associated with the AN 112 and also on STAs associated with AN 116. In an embodiment, the first association information may be based on a number of STAs associated with the AN 112 and on a number of STAs associated with the AN 116. The first association information may comprise these numbers. In a further embodiment, the first association information may comprise a sum of the number of STAs associated with the AN 112 and the number of STAs associated with the AN 116. The AN 112 may serve more than one AN 116, and the AN 116 may further serve other access nodes. Thus, the first association information may be based on a number of STAs associated to the AN 112 and on the number of STAs associated to any AN the AN 112 serves either directly or via another AN(s).

Figure 4 illustrates usage of different frequency bands/channels according to one or more embodiments. Numbers 301, 303, 306, and 308 refer to transmissions of Figure 3. Not shown in Figure 3, the AP 112 may transfer frames other than 301 with associated STAs 100-104. These transmissions may be called fronthaul BSS frame transmissions 400, as shown in Figure 4. Transmissions 303, 306, 308 occur in a channel #1 of the wireless network 140. Transmissions 301, 400 occur in a channel #2 of the wireless network 130. The channels #1 and #2 may use different frequency bands/channels as shown in Figure 4. The channel occupancy information received in message 306 may affect how the AP 112 uses the channel #1 of the wireless network 140. Transmissions within the wireless network 130 may be unaffected by the procedure described in Figure 3.

Figure 5 illustrate one or more embodiments from the viewpoint of an access node, e.g. the AP 112. The access node may perform one or more of the following features: establishing associations (block 501, corresponding to step 301 in Figure 3) with one or more STAs 100-104; transmitting the first message (block 503, corresponding to step 303 in Figure 3) to the MN 110 in a channel; receiving a channel occupancy information (block 506, corresponding to step 306 in Figure 3) in the channel, and operating in the channel according to the channel occupancy information (block 508, corresponding to step 308 in Figure 3). Block 508 may comprise determining at least one TXOP limit based at least partially on the channel occupancy information (block 509). Block 508 may further comprise operating in the channel according to the at least one TXOP limit (block 510). Block 510 may comprise contending for channel access to obtain a TXOP. Block 510 may comprise, after acquiring access to the channel by winning the channel contention, occupying the channel for a time period not exceeding the TXOP limit. Occupying the channel may comprise exchanging frames between the access node and the MN 110. After the time period, the access node may need to terminate the TXOP. In case the access node has more data to transmit, it may need to contend for channel access again.

Figure 6 illustrate one or more embodiments from the viewpoint of a node, e.g. the master node 110. The node may perform one or more of the following features: receiving a first message (block 603, corresponding to step 303 in Figure 3) from a first access node; receiving a second message (block 604, step 304) from a second access node; determining channel occupancy information for the first access node and the second access node (block 605, step 305); transmitting channel occupancy information to the first access node indicating at least partly a first maximum channel occupancy duration (block 606, step 306); transmitting channel occupancy information to the second access node indicating at least partly a second maximum channel occupancy duration (block 606, step 306). The first message, the second message, the channel occupancy information, the first maximum channel occupancy information, and the second maximum channel occupancy information may be as discussed in relation to Figure 3. Transmitting channel occupancy information to the first access node may comprise transmitting a first channel occupancy information to the first access node (block 606). Transmitting channel occupancy information to the second access node may comprise transmitting a second channel occupancy information to the second access node (607). The node may transmit separate messages (606, 607) wherein the messages may comprise same channel occupancy information, or different information, e.g. the first channel occupancy information and the second occupancy information. In an embodiment, the node may transmit channel occupancy information in a single message to both first access node and the second access node.

Figure 7 illustrate an example how the channel of the wireless network 140 may be occupied by the APs 112, 114. Here it is assumed that three ST As 100-104 are associated with the AP 112, and only one ST A is associated with the AP 114. In one or more embodiments described in context of Figures 3, 5, and 6, the result may then be that the first maximum channel occupancy duration, e.g. first TXOP limit, may be three times the second maximum channel occupancy duration, e.g. the second TXOP limit. This may be the case if TXOP limits are proportional to the number of associated STAs. Let’s assume that STAs both in the wireless network 130 and in the wireless network 132 have large data packets to transmit to uplink direction, and they thus transmit frames to the APs 112, 114 in those wireless networks. To transmit data of these frames further towards internet via the MN 110, the APs 112, 114 contend for channel access in the wireless network 140. If the AP 114 first obtains a TXOP, it may occupy the channel for a maximum duration 700, corresponding to the second TXOP limit. After this, the AP 112 may obtain a next TXOP and occupy the channel for a maximum duration 710, corresponding to the first TXOP limit. When this continues, the AP 112 may occupy the channel for durations 710, 711, 712 and the AP 114 may occupy the channel for durations 700, 701, 702. The order of these TXOPs may differ but the AP 112 is expected to occupy the channel for longer periods and thus traffic originated from the STAs in the wireless networks 130, 132 are expected to share the resources of the channel of the wireless network 140 more evenly than without the embodiments described in Figures 3, 5 and 6. The following table shows an example.

Figure 8 illustrates an embodiment of a structure of the above-mentioned functionalities of an apparatus executing the functions of the access node 112 or 114 in the process of Figure 5 or any one of the embodiments described above for the access node 112 or 114. The apparatus may be an access point or a client device, e.g. for a wireless local area network. In other embodiments, the apparatus may be a circuitry or an electronic device realizing some embodiments of the invention in the access node. The apparatus may comply with 802.11 specifications. The apparatus may be or may be comprised in a computer (PC), a laptop, a tablet computer, a cellular phone, a palm computer, a sensor device, or any other apparatus provided with radio communication capability. In another embodiment, the apparatus carrying out the above-described functionalities is comprised in such a device, e.g. the apparatus may comprise a circuitry such as a chip, a chipset, a processor, a micro controller, or a combination of such circuitries in any one of the above -described devices. The apparatus may be an electronic device comprising electronic circuitries for realizing some embodiments of the present invention.

Referring to Figure 8, the apparatus may comprise a communication circuitry 800 providing the apparatus with capability of communicating in the wireless network 140. The communication circuitry 800 entity may comprise a radio interface 812 providing the apparatus with radio communication capability. The radio interface 812 may comprise radio frequency converters and other radio frequency components such as an amplifier, filter, and frequency-converter circuitries and one or more antennas. The communication circuitry 800 may further comprise a radio modem 816 configured to carry out transmission and reception of messages in the wireless network. The radio modem 816 may comprise encoder and decoder circuitries, modulator and demodulator circuitries, etc. The communication circuitry 800 may further comprise a channel occupation circuitry 818 configured to, for example, to determine number of stations associated with a first access node and/or to determine a first maximum channel occupancy duration 508, 509.

The communication circuitry 800 may further comprise a controller 814 configured to control transmissions and functions of the communication circuitry 800. The controller 814 may, for example, control establishment of an association between the access node 112 and the master node 110, control transmission of the message 303, 503, control reception of the message 306, 506, control channel usage comprising e.g. channel contention and channel occupation, as disclosed in steps 508, 509, and/or 510. Some of these tasks may comprise controlling the radio modem 816 to transmit/receive the above-mentioned messages. The communication circuitry 800 may comprise at least one processor comprising the controller 814 and the channel usage circuitry 818 and, optionally, at least some of the circuitries of the radio modem 816.

The apparatus may further comprise an application processor 840 executing one or more computer program applications that generate a need to transmit and/or receive data through the communication circuitry 800. The application processor may form an application layer of the apparatus. The application processor may execute computer programs forming the primary function of the apparatus. The application processor may generate data to be transmitted in the wireless network.

The apparatus may further comprise a memory 830 storing one or more computer program products 832 configuring the operation of said processor(s) of the apparatus. The memory 830 may further store a configuration database 834 storing operational configurations of the apparatus. The configuration database 834 may, for example, store the first maximum channel occupancy duration.

The apparatus may further comprise an AP entity 820 providing the apparatus with capability of communicating in the wireless network 130. The AP entity may further comprise, as an example, a radio interface, a radio modem, and/or a controller. The AP entity may perform functions for establishing one or more associations between the access node 112 and STAs 100-104.

Figure 9 illustrates an embodiment of a structure of the above-mentioned functionalities of an apparatus executing the functions of the master node 110 in the process of Figure 6 or any one the embodiments described above for the master node 110. The apparatus may be a controller node or an access point, e.g. for a wireless local area network. In other embodiments, the apparatus may be a circuitry or an electronic device realizing some embodiments of the invention in the access node. The apparatus may comply with 802.11 specifications. The apparatus may be or may be comprised in a server, a computer (PC), a laptop, a tablet computer, a cellular phone, or any other apparatus provided with radio communication capability. In another embodiment, the apparatus carrying out the above-described functionalities is comprised in such a device, e.g. the apparatus may comprise a circuitry such as a chip, a chipset, a processor, a micro controller, or a combination of such circuitries in any one of the above -described devices. The apparatus may be an electronic device comprising electronic circuitries for realizing some embodiments of the present invention.

Referring to Figure 9, the apparatus may comprise a first communication interface 940 or a communication circuitry configured to provide the apparatus with capability for bidirectional communication with backhaul STAs, e.g. APs 112, 114 over a radio interface. The communication interface may comprise radio frequency circuitries for processing received control frames and data frames and control frames and data frames to be transmitted. The communication interface 940 may comprise standard well-known components such as an antenna array, amplifier, a filter, a frequency converter, and encoder/decoder circuitries. The communication interface 940 may comprise circuitries for processing messages described above in connection with signals 303-307, and/or blocks 603-607.

The apparatus may further comprise a second communication interface 950 or a communication circuitry configured to provide the apparatus with capability for bidirectional communication with other networks, e.g. the Internet or another computer network or another wireless network.

The apparatus may further comprise a memory 920 storing one or more computer program products 922 configuring the operation of at least one processor of the apparatus. The memory 920 may further store a configuration database 924 storing operational configurations of the apparatus. The configuration database 924 may, for example, store number of associated stations and/or channel occupancy information per AP 212, 214.

The apparatus may further comprise the at least one processor configured to carry out the process of Figure 6 or any one of its embodiments. The processor may comprise a communication controller 900 controlling the operation of the master node 110. Referring to Figure 9, the communication controller or the at least one processor may comprise the channel usage controller 910 and a transmission circuitry 930. The transmission circuitry may carry out frame transmissions in a wireless network managed by the apparatus. The frame transmissions may include transmissions of frames to STAs associated to the apparatus. The frame transmissions may include the setup of the channel occupancy duration parameters, as described above.

The communication controller 900 may comprise an association setup circuitry 960 configured to perform the establishment of associations, occurring before the block 603 in the process of Figure 6. The communication controller 900 may further comprise a channel usage controller 910 for managing the process of Figure 6. The channel usage controller may comprise a network information acquisition entity 914 for acquiring network information, block 604, via the communication interface 940. The channel usage controller 910 may comprise a channel occupation control entity 916 for determining channel occupancy information for at least two access nodes, block 605. As used in this application, the term ‘circuitry’ refers to one or more of the following: (a) hardware-only circuit implementations such as implementations in only analog and/or digital circuitry; (b) combinations of circuits and software and/or firmware, such as (as applicable): (i) a combination of processor(s) or processor cores; or (ii) portions of processor(s)/software including digital signal processor(s), software, and at least one memory that work together to cause an apparatus to perform specific functions; and (c) circuits, such as a microprocessor(s) or a portion of a microprocessor(s), that require software or firmware for operation, even if the software or firmware is not physically present.

This definition of ‘circuitry’ applies to uses of this term in this application. As a further example, as used in this application, the term “circuitry” would also cover an implementation of merely a processor (or multiple processors) or portion of a processor, e.g. one core of a multi-core processor, and its (or their) accompanying software and/or firmware. The term “circuitry” would also cover, for example and if applicable to the particular element, a baseband integrated circuit, an application-specific integrated circuit (ASIC), and/or a field-programmable grid array (FPGA) circuit for the apparatus according to an embodiment of the invention.

The processes or methods described in Figures 3, 5, and 6 may also be carried out in the form of one or more computer processes defined by one or more computer programs. A separate computer program may be provided in one or more apparatuses that execute functions of the processes described in connection with the Figures. The computer program(s) may be in source code form, object code form, or in some intermediate form, and it may be stored in some sort of carrier, which may be any entity or device capable of carrying the program. Such carriers include transitory and/or non-transitory computer media, e.g. a record medium, computer memory, read-only memory, electrical carrier signal, telecommunications signal, and software distribution package. Depending on the processing power needed, the computer program may be executed in a single electronic digital processing unit or it may be distributed amongst a number of processing units.

Embodiments described herein are applicable to wireless networks defined above but also to other wireless networks. The protocols used, the specifications of the wireless networks and their network elements develop rapidly. Such development may require extra changes to the described embodiments. Therefore, all words and expressions should be interpreted broadly, and they are intended to illustrate, not to restrict, the embodiment. It will be obvious to a person skilled in the art that, as technology advances, the inventive concept can be implemented in various ways. Embodiments are not limited to the examples described above but may vary within the scope of the claims.

Claims

1. An apparatus for a wireless network, comprising means for performing: receiving a first message from a first access node, wherein the first message comprises a first association information, wherein the first association information is based on a number of wireless devices associated with the first access node; receiving a second message from a second access node, wherein the second message comprises a second association information, wherein the second association information is based on a number of wireless devices associated with the second access node; determining at least channel occupancy information indicating at least partly a first maximum channel occupancy duration, wherein the channel occupancy information is based at least partly on the first association information and on the second association information; transmitting the channel occupancy information to the first access node.

2. The apparatus of claim 1 , wherein said determining at least the channel occupancy information comprises determining another channel occupancy information indicating at least partly a second maximum channel occupancy duration, different from the first maximum channel occupancy duration, wherein the another channel occupancy information is based at least partly on the first association information and on the second association information, and wherein the apparatus further comprises means for transmitting the another channel occupancy information to the second access node.

3. The apparatus of any preceding claim, wherein the channel occupancy information is at least partly proportional to the first association information.

4. The apparatus of claim 2, wherein the another channel occupancy information is at least partly proportional to the second association information.

5. The apparatus of claim 1, wherein the channel occupancy information indicates at least partly a second maximum channel occupancy duration, and wherein the apparatus further comprises means for transmitting the channel occupancy information to the second access node.

6. The apparatus of claim 5, wherein the first maximum channel occupancy duration is based at least partly on the first association information and on the channel occupancy information and wherein the second maximum channel occupancy duration is based at least partly on the second association information and on the channel occupancy information.

7. The apparatus of any preceding claim, wherein the channel occupancy information is based at least partly on the sum of the first association information and the second association information.

8. The apparatus of any preceding claim, wherein the first association information comprises a number of the wireless devices associated with the first access node and the second association information comprises a number of the wireless devices associated with the second access node.

9. The apparatus of any preceding claim, wherein the first maximum channel occupancy duration is proportional to the first association information.

10. The apparatus of claim 2 or 5, wherein the second maximum channel occupancy duration is proportional to the second association information.

11. The apparatus of any preceding claim, wherein the first maximum channel occupancy duration is a transmission opportunity limit.

12. The apparatus of any preceding claim, wherein the channel occupancy information indicates a plurality of transmission opportunity limits, wherein at least part of the plurality of transmission opportunity limits are per access category.

13. The apparatus of any preceding claim, wherein the apparatus is a gateway node providing access to an external network.

14. The apparatus of any preceding claim, wherein the apparatus comprises at least a control node.

15. The apparatus of any preceding claim, wherein the first access node is an access point of a first wireless local area network and the second access node is an access point of a second wireless local area network and the wireless devices associated with the first access node and the wireless devices associated with the second access node are stations.

16. The apparatus of any preceding claim, wherein the apparatus is an access point in the wireless network, the first access node is a station of the wireless network and the second access node is another station in the wireless network.

17. The apparatus of any preceding claim wherein said transmitting the channel occupancy information to the first access node comprises transmitting the channel occupancy information to the first access node on a frequency channel, and wherein the channel occupancy information indicates a maximum time the first access node may continuously occupy the frequency channel.

18. The apparatus of any preceding claim, wherein the first message is an access point metrics response message.

19. An apparatus for a wireless network, comprising means for causing an access node to perform: transmitting a first message on a channel to a master node, wherein the first message comprises a first association information, wherein the first association information is based on a number of wireless devices associated with the access node; receiving, on the channel from the master node, a channel occupancy information, indicating at least partly a maximum channel occupancy duration, wherein the channel occupancy information is based at least partly on the first association information and on a second association information, wherein the second association information is based on a number of wireless devices associated with a second access node; operating on the channel according to the channel occupancy information.

20. The apparatus of claim 19, wherein communications between the access node and the wireless devices associated with the access node are performed on another channel.

21. The apparatus of any preceding claim 19 to 20, wherein the first association information comprises a number of the wireless devices associated with the access node.

22. The apparatus of any preceding claim 19 to 21, wherein the maximum channel occupancy duration is a transmission opportunity limit.

23. The apparatus of any preceding claim 19 to 22, wherein the access node is an access point of a wireless local area network and the master node is a gateway node providing access to an external network

24. The apparatus of any preceding claim 19 to 23, wherein the channel is a frequency channel.

25. The apparatus of any preceding claim 1 to 24, wherein the means comprises: at least one processor; and at least one memory comprising computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the performance of the apparatus.

26. A method comprising: receiving, by an apparatus for a wireless network, a first message from a first access node, wherein the first message comprises a first association information, wherein the first association information is based on a number of wireless devices associated with the first access node; receiving, by the apparatus a second message from a second access node, wherein the second message comprises a second association information, wherein the second association information is based on a number of wireless devices associated with the second access node; determining, by the apparatus, at least channel occupancy information indicating at least partly a first maximum channel occupancy duration, wherein the channel occupancy information is based at least partly on the first association information and on the second association information; transmitting, by the apparatus, the channel occupancy information to the first access node.

27. The method of claim 26, wherein said determining at least the channel occupancy information comprises determining another channel occupancy information indicating at least partly a second maximum channel occupancy duration, different from the first maximum channel occupancy duration, wherein the another channel occupancy information is based at least partly on the first association information and on the second association information, and wherein the method further comprises transmitting the another channel occupancy information to the second access node.

28. The method of any preceding claim 26 to 27, wherein the channel occupancy information is at least partly proportional to the first association information.

29. The method of claim 27, wherein the another channel occupancy information is at least partly proportional to the second association information.

30. The method of claim 26, wherein the channel occupancy information indicates at least partly a second maximum channel occupancy duration, and wherein the further comprises transmitting the channel occupancy information to the second access node.

31. The method of claim 30, wherein the first maximum channel occupancy duration is based at least partly on the first association information and on the channel occupancy information and wherein the second maximum channel occupancy duration is based at least partly on the second association information and on the channel occupancy information.

32. The method of any preceding claim 26 to 31, wherein the channel occupancy information is based at least partly on the sum of the first association information and the second association information.

33. The method of any preceding claim 26 to 32, wherein the first association information comprises a number of the wireless devices associated with the first access node and the second association information comprises a number of the wireless devices associated with the second access node.

34. The method of any preceding claim 26 to 33, wherein the first maximum channel occupancy duration is proportional to the first association information.

35. The method of claim 27 or 30, wherein the second maximum channel occupancy duration is proportional to the second association information.

36. The method of any preceding claim 26 to 35, wherein the first maximum channel occupancy duration is a transmission opportunity limit.

37. The method of any preceding claim 26 to 36, wherein the channel occupancy information indicates a plurality of transmission opportunity limits, wherein at least part of the plurality of transmission opportunity limits are per access category.

38. The method of any preceding claim 26 to 37, wherein the apparatus is a gateway node providing access to an external network.

39. The method of any preceding claim 26 to 38, wherein the apparatus comprises at least a control node.

40. The method of any preceding claim 26 to 39, wherein the first access node is an access point of a first wireless local area network and the second access node is an access point of a second wireless local area network and the wireless devices associated with the first access node and the wireless devices associated with the second access node are stations.

41. The method of any preceding claim 26 to 40, wherein the apparatus is an access point in the wireless network, the first access node is a station of the wireless network and the second access node is another station in the wireless network.

42. The method of any preceding claim 26 to 41, wherein said transmitting the channel occupancy information to the first access node comprises transmitting the channel occupancy information to the first access node on a frequency channel, and wherein the channel occupancy information indicates a maximum time the first access node may continuously occupy the frequency channel.

43. The method of any preceding claim 26 to 42, wherein the first message is an access point metrics response message.

44. A method comprising: transmitting, by an apparatus for a wireless network, a first message on a channel to a master node, wherein the first message comprises a first association information, wherein the first association information is based on a number of wireless devices associated with the access node; receiving, by the apparatus on the channel from the master node, a channel occupancy information, indicating at least partly a maximum channel occupancy duration, wherein the channel occupancy information is based at least partly on the first association information and on a second association information, wherein the second association information is based on a number of wireless devices associated with a second access node; operating, by the apparatus, on the channel according to the channel occupancy information.

45. The method of claim 44, wherein communications between the access node and the wireless devices associated with the access node are performed on another channel.

46. The method of any preceding claim 44 to 45, wherein the first association information comprises a number of the wireless devices associated with the access node.

47. The method of any preceding claim 44 to 46, wherein the maximum channel occupancy duration is a transmission opportunity limit.

48. The method of any preceding claim 44 to 47, wherein the access node is an access point of a wireless local area network and the master node is a gateway node providing access to an external network

49. A computer program product embodied on a computer-readable medium and comprising a computer program code readable by a computer for an apparatus of a wireless network, wherein the computer program code configures the computer to carry out a computer process comprising: receiving a first message from a first access node, wherein the first message comprises a first association information, wherein the first association information is based on a number of wireless devices associated with the first access node; receiving a second message from a second access node, wherein the second message comprises a second association information, wherein the second association information is based on a number of wireless devices associated with the second access node; determining at least channel occupancy information indicating at least partly a first maximum channel occupancy duration, wherein the channel occupancy information is based at least partly on the first association information and on the second association information; transmitting the channel occupancy information to the first access node.

50. A computer program product embodied on a computer-readable medium and comprising a computer program code readable by a computer for an apparatus of a wireless network, wherein the computer program code configures the computer to carry out a computer process comprising: transmitting a first message on a channel to a master node, wherein the first message comprises a first association information, wherein the first association information is based on a number of wireless devices associated with the access node; receiving, on the channel from the master node, a channel occupancy information, indicating at least partly a maximum channel occupancy duration, wherein the channel occupancy information is based at least partly on the first association information and on a second association information, wherein the second association information is based on a number of wireless devices associated with a second access node; operating on the channel according to the channel occupancy information.