WO2020041997A1

WO2020041997A1 - Methods, devices and computer readable medium for recovering connections in communication systems

Info

Publication number: WO2020041997A1
Application number: PCT/CN2018/102891
Authority: WO
Inventors: Erma Perenda; Haris Gacanin
Original assignee: Nokia Shanghai Bell Co., Ltd.; Nokia Solutions And Networks Oy
Priority date: 2018-08-29
Filing date: 2018-08-29
Publication date: 2020-03-05
Also published as: CN112449765A; EP3845027A1; EP3845027A4

Abstract

A method, device and computer readable medium are described for recovering connections in communication systems. Each device in the network keeps a record of its next-hop device to gateway and updates the quality of link between itself and the next-hop device. If a segment of network is disconnected from the internet, the devices cooperate with each other and a leader device is determined to take over search for path to gateway. The path is determined based on the record and the quality of link. In this way, time for recovering connection of the segment of network is significantly decreased.

Description

METHODS, DEVICES AND COMPUTER READABLE MEDIUM FOR RECOVERING CONNECTIONS IN COMMUNICATION SYSTEMS

FIELD

Embodiments of the present disclosure generally relate to communication techniques, and more particularly, to methods, devices and computer readable medium for recovering connections in communication systems.

BACKGROUND

Communication technologies are developing rapidly. For example, Multi-radios Multi-channels Wireless Mesh Networks (MRMC-WMNs) are being very rapidly deployed into home and enterprise environments. In principle, WMN care systems rely on direct connectivity (i.e., backbone) between the user and static knowledge data base that cannot adapt to changes in the user and network environment. Due to the nature of wireless transmission, each Wi-Fi node in WMN should be able to recover its failed links within as short time as it is possible. Self-care in WMN is attractive approach to reduce interaction with the operator’s help desk and lower operator’s OPEX.

SUMMARY

Generally, embodiments of the present disclosure relate to a method for recovering connections in communication systems.

In a first aspect, embodiments of the disclosure provide a terminal device. The device comprises: at least one processor; at least one memory including computer program codes; the at least one memory and the computer program codes are configured to, with the at least one processor, cause the device at least to in response to losing a connection between a first device and a gateway in a network, determine whether the first device is connected to a second device. The second devices locates between the first device and the gateway. The device is further caused to select a target device from one or more candidate devices in the network, in response to determining that the first device is disconnected from the second device. Each of the candidate devices is connectable to the gateway. The device is further caused to establish a connection with the target device for reestablishing the connection to the gateway.

In a second aspect, embodiments of the present disclosure provide a communication method. The method comprises in response to losing a connection between a first device and a gateway in a network, determining whether the first device is connected to a second device. The second device locates between the first device and the gateway. The method further comprises in response to determining that the first device is disconnected from the second device, selecting a target device from one or more candidate devices in the network. Each of the candidate devices is connectable to the gateway. The method comprises establishing a connection with the target device for reestablishing the connection to the gateway.

In a third aspect, embodiments of the disclosure provide an apparatus. The apparatus comprises means for in response to losing a connection between a first device and a gateway in a network, determining whether the first device is connected to a second device. The second device locates between the first device and the gateway. The apparatus also comprises means for in response to determining that the first device is disconnected from the second device, selecting a target device from one or more candidate devices in the network. Each of the candidate devices is connectable to the gateway. The apparatus further comprises means for establishing a connection with the target device for reestablishing the connection to the gateway.

In a fourth aspect, embodiments of the disclosure provide a computer readable medium. The non-transitory computer-readable medium stores instructions for causing an apparatus to perform in response to losing a connection between a first device and a gateway in a network, determining whether the first device is connected to a second device. The second device locates between the first device and the gateway. The apparatus is also caused to perform in response to determining that the first device is disconnected from the second device, selecting a target device from one or more candidate devices in the network. Each of the candidate devices is connectable to the gateway. The apparatus is further caused to perform establishing a connection with the target device for reestablishing the connection to the gateway.

Other features and advantages of the embodiments of the present disclosure will also be apparent from the following description of specific embodiments when read in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of embodiments of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the disclosure are presented in the sense of examples and their advantages are explained in greater detail below, with reference to the accompanying drawings, where

Fig. 1 illustrates a schematic diagram of a communication system according to conventional technologies;

Fig. 2 illustrates a schematic diagram of a cloud-based system according to conventional solutions;

Fig. 3 illustrates a schematic diagram of a mobile application-based system according to conventional solutions;

Fig. 4 illustrates a schematic diagram of a communication system according to embodiments of the present disclosure;

Fig. 5 illustrates a schematic diagram of an example topology of a communication system according to embodiments of the present disclosure;

Fig. 6 illustrates a flow chart of a method according to embodiments of the present disclosure; and

Fig. 7 illustrates a schematic diagram of a device according to embodiments of the present disclosure.

Throughout the figures, same or similar reference numbers indicate same or similar elements.

DETAILED DESCRIPTION OF EMBODIMENTS

The subject matter described herein will now be discussed with reference to several example embodiments. It should be understood these embodiments are discussed only for the purpose of enabling those skilled persons in the art to better understand and thus implement the subject matter described herein, rather than suggesting any limitations on the scope of the subject matter.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a, ” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises, ” “comprising, ” “includes” and/or “including, ” when used herein, specify the presence of stated features, integers, steps, operations, elements and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof.

It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two functions or acts shown in succession may in fact be executed concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.

As used herein, the term “communication network” refers to a network following any suitable communication standards, such as Long Term Evolution (LTE) , LTE-Advanced (LTE-A) , Wideband Code Division Multiple Access (WCDMA) , High-Speed Packet Access (HSPA) , Wireless Fidelity (Wi-Fi) , and so on. Furthermore, the communications between a terminal device and a network device in the communication network may be performed according to any suitable generation communication protocols, including, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.75G, the third generation (3G) , the fourth generation (4G) , 4.5G, the future fifth generation (5G) communication protocols, IEEE 802.11 protocols, and/or any other protocols either currently known or to be developed in the future.

Embodiments of the present disclosure may be applied in various communication systems. Given the rapid development in communications, there will of course also be future type communication technologies and systems with which the present disclosure may be embodied. It should not be seen as limiting the scope of the present disclosure to only the aforementioned system.

The term “device” used herein refers to any proper devices which are capable of communication. For example, the term “device” may refer to a network device or a terminal device. The term “network device” includes, but not limited to, a base station (BS) , a gateway, a management entity, and other suitable device in a communication system. The term “base station” or “BS” represents a node B (NodeB or NB) , an evolved NodeB (eNodeB or eNB) , a NR NodeB (gNB) , a Remote Radio Unit (RRU) , a radio header (RH) , a remote radio head (RRH) , a relay, a low power node such as a femto, a pico, a router and so forth.

The term “terminal device” includes, but not limited to, “user equipment (UE) ” and other suitable end device capable of communicating with the network device. By way of example, the “terminal device” may refer to a terminal, a Mobile Terminal (MT) , a Subscriber Station (SS) , a Portable Subscriber Station, a Mobile Station (MS) , or an Access Terminal (AT) .

The term “extender” used herein refers to a device that can improve coverage of a communication system (for example, a Wi-Fi communication sytem) .

The term “circuitry” used herein may refer to one or more or all of the following:

(a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and

(b) combinations of hardware circuits and software, such as (as applicable) :

(i) a combination of analog and/or digital hardware circuit (s) with

software/firmware and

(ii) any portions of hardware processor (s) with software (including digital signal processor (s) ) , software, and memory (ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and

(c) hardware circuit (s) and or processor (s) , such as a microprocessor (s) or a portion of a microprocessor (s) , that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation. ”

This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

Global WMN optimization of channels or route is performed under critical assumption that backbone connects all the nodes in the network. However, if a part of the network is disconnected from the backbone, global routing or channel selection algorithms cannot be utilized.

As mentioned above, self-care in WMN is attractive approach to reduce interaction with the operator’s help desk and lower operator’s OPEX. In particular, WMN self-care systems of today rely on lab derived rules that are reused across different deployments such as home but differences among deployments are not taken into consideration. Generally speaking, there may be three main reasons for losing connections among nodes in WMN: (1) Bad channel configuration which may comprise channel mismatching caused by dynamic channel selection or channel with very poor performance; (2) Repositioning of nodes by users; (3) Malfunction of a certain node.

As an example, in a situation of losing connection among nodes in the WMN, the backend server cannot reach a particular node and change its configurations to new optimal configurations, which lead to dead time in the WMN. In such situations, users have to experience loss of service or very poor performance, thereby leading to increased operator’s help-desk.

Fig. 1 illustrates a schematic diagram of a communication system 100 according to conventional solutions. The communication system 100 comprises a gateway 110 with the gate toward internet 130 and extenders 120-1, 120-2, 120-3, ...., 120-8 (collectively referred as “extender 120” ) . The extenders 120 are connected to the gateway 110 directly or through other extenders. For example, the extenders 210-1 and 120-2 are connected with the gateway 110 directly. The extender 120-4 is connected to the gateway 110 through the extender 120-1. The extenders 120-3, 120-5, 120-6, 120-7 and 120-8 are connected to the gateway 110 through the extender 120-2.

Assuming that the gateway 110 and the extenders 120 have two radios, one radio is 2.4 GHz and the other radios is 5GHz. In the communication system 100, the best path to the gateway 110 is found for each of the extenders 120 and the topology for the communication 100 is optimized at a time instant t ₁. As shown in Fig. 1, the gateway 110 is connected to the extenders 120-1 and 120-2 with 5GHz radio to which is assigned a channel with index 52. At a time instant t ₂, the gateway 110 triggers 5GHz band and new channel is a channel with index 100. The gateway 110 and the extender 120-1 reset the channel to 100, but the extender 120-2 remains staying on channel 52. The extender 120-3 with its descendants (the extenders 120-5, 120-6, 120-7 and 120-8) lose the connection with the gateway 110. All user devices associated with the extenders 120-3 to 120-8 are disconnected from the internet 130.

In the above situation, the extenders 120-3 to 120-8 may try to reconnect to the gateway, which may cause the following problems:

1. Ripple effect -Without the coordination among the extender 120-3 and its descendants, each of them will try to find the right channel or right route toward the gateway 110, which will cause ripple effect in the communication system 100 and will consequently increase dead time for their associated user devices.

2. Long search duration -although each extender 120 in the communication system 100 has the same mesh id, they can work on different channels if topology allows it, which makes a search for right channel more challenging. By scanning its neighbors mesh peers, the extender 120 can detect different channels. Exhaustive brute-force search for right channel might take a long time to search right channel and it can fail to find a solution within any practical length of time.

There are several conventional solutions for self-care WMN systems. Fig. 2 illustrates a schematic diagram of a cloud-based solution. The cloud-based system 200 comprises a remote web interface 210 at a backend server and an optimization engine 220. The remote web interface 210 at the backend server is not helpful at all in case of lost connections among extenders.

Fig. 3 illustrates a schematic diagram of a mobile application-based solution. The mobile-application based system 300 comprise, a master Access Point (AP) 310, a terminal device 330 directly connected to the master AP 310, and extenders 320-1, 320-2 and 320-3. The terminal device 330 may have an application run thereon. The application may implement the following functions: speed test, network management and network status. The efficiency of applications depends on the connecting node to which the terminal device 330 is connected. Mobile applications give only insights in status of the Wi-Fi system (e.g., list of connected device, speed tests) with a list of recommendations as possible solutions and they often interact with cloud server. However, both involve users with wasting their time to resolve problem.

The conventional solution also comprises a local self-care system. The local self-care system hosts some logic locally to each node with self-healing capability for channel-related failures. The simplest approach for channel-related failures is brute-force search for the right channel which is not reliable in multi-radios multi-channels WMN and needs a long search time to find the right channel. Moreover, it doesn’t have any cooperation among nodes in WMN what often leads to ripple-effect.

There is an improved approach for self-care for channel-related failures in multi radio WMN named Localized sElf-reconfiGuration algOrithms (LEGO) . The LEGO distinguishes three phases: 1) actively network monitoring done by each node, 2) reconfiguration for group nodes impacted by link failure and electing the leader of the group, 3) and the network planning via a constraint graph phase keeping network changes as local as possible.

A key idea behind the LEGO is that it takes a top-down approach to generate reconfiguration plans mainly for minimizing network changes. The LEGO generates all possible changes such as channel switching, radio association change and detouring per each link in a group and based on them makes a list of feasible reconfiguration plans. The LEGO selects the plan which satisfies QoS requirements and doesn’t cause the cascaded changes of network settings (no ripple effects) . However, the LEGO approach considers WMN where each node has its own gate to Internet, it cannot be applied to conventional WMN topology illustrated in Fig. 1. Furthermore, the LEGO still needs a long search time to check feasibility of each plan and doesn’t utilizes learning based on past experience.

Another self-care system which is based on the election of the leader node is given for Zigbee tree network which aims to minimize the number of descendants that needs to re-join the network from scratch by keeping the initial topology of the sub-tree as far as possible, and by means of that minimizing the cost due to re-joining to the network from scratch (huge number of control messages) .

In order to at least in part solve above and other potential problems, embodiments of the present disclosure provide a solution for recovering connections in communication systems. Example embodiments of the present disclosure are described below with reference to the figures. However, those skilled in the art would readily appreciate that the detailed description given herein with respect to these figures is for explanatory purpose as the present disclosure extends beyond theses limited embodiments.

Fig. 4 illustrates a schematic diagram of a communication system 400 in which embodiments of the present disclosure can be implemented. The communication system 400, which is a part of a communication network, includes a gateway 410 and devices 420-1, 420-2, ..., and 420-N (collectively referred to as “device 420” where N is an integer number) . It is to be understood that the communication system 400 may include any suitable number of devices. It should be noted that the communication system 400 may also include other elements which are omitted for the purpose of clarity. The device 420 may refer to an extender. Alternatively or in addition, the device 420 may refer to a repeater. In some embodiments, the device may be implemented at an Access Point (AP) .

Communications in the communication system 400 may be implemented according to any proper communication protocol (s) , including, but not limited to, cellular communication protocols of the first generation (1G) , the second generation (2G) , the third generation (3G) , the fourth generation (4G) and the fifth generation (5G) and on the like, wireless local network communication protocols such as Institute for Electrical and Electronics Engineers (IEEE) 802.11 and the like, and/or any other protocols currently known or to be developed in the future. Moreover, the communication may utilize any proper wireless communication technology, including but not limited to: Code Divided Multiple Address (CDMA) , Frequency Divided Multiple Address (FDMA) , Time Divided Multiple Address (TDMA) , Frequency Divided Duplexer (FDD) , Time Divided Duplexer (TDD) , Multiple-Input Multiple-Output (MIMO) , Orthogonal Frequency Divided Multiple Access (OFDMA) and/or any other technologies currently known or to be developed in the future.

According to embodiments of the present disclosure, each device in the network keeps a record of its next-hop device to gateway and updates the quality of link between itself and the next-hop device. If a segment of network is disconnected from the internet, the devices cooperate with each other and a leader device is determined to take over search for path to gateway. The path is determined based on the record and the quality of link. In this way, time for recovering connection of the segment of network is significantly decreased. The problem of recovery of network segment can be solved without connectivity to backbone.

Fig. 5 illustrates a schematic diagram of an example topology 500 of the communication system 400. It should be noted that the example topology 500 is only an example not limitations. The communication system 400 may have any suitable topologies. Only for the purpose of illustrations, embodiments of the present disclosure are described with the reference to the topology shown in Fig. 5.

As shown in Fig. 5, the devices 420-1, 420-2, 420-3 and 420-4 are directly connected to the gateway 410. The device 420-5 is connected to gateway 410 through the device 420-1. The devices 420-6, 420-7 and 420-8 are connected to the gateway through the device 420-5. The devices 420-6, 420-7 and 420-8 are the descendant devices of the device 420-5.

Fig. 6 illustrates a flow chart of a method 600 according to embodiments of the present disclosure. The method 600 may be implemented at the devices 420.

In some embodiments, the devices 420 (for example, the devices 420-1, 420-2, 420-3, 420-3, ..., 420-8) monitor the path to gateway 410. By way of example, the device 420-5 may keep a list of candidate devices that may be connectable to the gateway 410. For example, the list of candidate devices may include the device 420-1, 420-2, 420-3 and 420-4.

The device 420-5 may obtain information of the candidate devices. The information may include, but not limit to one or more of the followings: an identity of each candidate device, link quality with each candidate device, and a frequency band used by each candidate device. The link quality value The link quality value l _next-hop (t ₂) at time instant t ₂ uses the Q-learning approach and may be calculated based on the following formula 1:

l _next-hop (t ₂) = (1-γ) l _next-hop (t ₁) + γr _next-hop (t ₂) (1)

where t ₂ ＞ t ₁, γ is learning factor and r _next-hop is current link quality which is given as the following formula 2:

where errorRate and retriesRate denote error rate and retransmission rate for a link among the certain device and its next-hop, while rssiFactor is given as

where RSSI is the signal strength of the next hop.

In an example embodiment, the device 420-5 may be periodically obtain the information of the candidate devices and updated its record. The device 420-5 may keep monitoring the network and obtain the information as long as it connects with the gateway 410.

In some embodiments, the device 420-5 stores the information of the candidate devices in a local storage or a remote storage. The device 420-5 may also update the information of the candidate devices to the gateway 410.

At block 610, the device 420-5 determines whether it is connected to the device 420-1 if the connection between the device 420-5 and the gateway 410 is lost. For example, if a segment of network comprising the devices 420-5, 420-6, 420-7 and 420-8 is disconnected from the gateway 410, each of the above devices tries to ping its next-hop device. The devices 420-6 and 420-7 may ping the device 420-5 and the device 420-8 may ping the device 420-7.

In some embodiments, if the next-hop device is reachable, the device may way for a certain period to receive a notification from a device that is closeted to the gateway 410. For example, if the device 420-7 is able to reach the device 420-5, the device 420-7 may receive a notification from the device 420-5.

In an example embodiment, if the device cannot reach its next-hop, the device may become a leader device. For example, if the device 420-5 cannot reach the device 420-1, the device 420-5 may broadcast information to its descendant devices (i.e., the devices 420-6, 420-7 and 420-8) . The information indicates that the device 420-5 is the leader device and responsible for searching path to gateway 410.

In some embodiments, if the devices 420-6, 420-7 and 420-8 receive the information, the devices 420-6, 420-7 and 420-8 may transmit a response to the device 420-5. The response may include, but not limit to, one or more of the following: an MAC address of each descendant device, current next-hop of each descendant device and a channel used for link towards the next hop.

At block 620, the device 420-5 selects a target device from one or more candidate device in the network if the device 420-5 is disconnected from the device 420-1. In some embodiments, the device 420-5 may tune its radio into scanning mode. Since each device has a same Service Set Identifier (SSID) values, the device 420-5 may obtain scanning results (for example, Basic SSID (BSSID) and channel index pair) that corresponds to the same SSID and remove each of its descendant devices from the list of candidate devices.

In some embodiments, the device 450-2 may create a priority queue for best-first search algorithm based on previously monitored information. The next-hop device with the highest link quality is the first one in the list of the candidate devices. For example, if the device 420-2 has the highest link quality, the device 450-2 may select the device 420-2 as the target device. In this way, the search for the right device is shortened.

At block 630, the device 420-5 establishes a connection with the target device for reestablishing the connection to the gateway 410. In an example embodiment, the device 420-5 may determine whether a channel used for connecting to the device 420-2 is a dynamic frequency selection (DFS) channel. If the channel is a DFS channel, the device 420-5 may determine whether the channel is enabled. If the channel is enabled, the device 420-5 may establish the connection with the target device. If the channel is disabled, the device 420-5 may determine another candidate device to be the target device.

In an example embodiment, the device 420-5 may obtain a channel available to the target device. The device 420-5 may determine which descendant device needs to change its channel to the channel available to the target device. For example, the device 420-5 may determine that the device 420-6 needs to change its channel, the device 420-5 may transmit a channel switching request to the device 420-6. The device 420-6 may change its channel based on the request.

In some embodiment, the device 420-5 may check whether it can reach the gateway 410 after the connection with the target device is established. If the device 420-5 still cannot reach the gateway 410, the device 420-5 may transmit a request to the connected target device to obtain descendant devices of the connected target device. After the list of checked and unsuitable candidate’s descendant devices is received, the device 420-5 removes those devices from the list and continues to check for other candidates in the list. It moves the checked candidates to the closed list. If all candidate devices are checked, but gateway 410 cannot be reached, the leader node role is passed to the next closest device to the device 420-5, since the current leader device 420-5 becomes a descendant device to new leader device. It might happen that the only path to gateway can be reached through one of descendant device.

In some embodiments, an apparatus for performing the method 600 (for example, the device 420-5) may comprise respective means for performing the corresponding steps in the method 600. These means may be implemented in any suitable manners. For example, it can be implemented by circuitry or software modules.

In some embodiments, the apparatus, comprising: means for in response to losing a connection between a first device and a gateway in a network, determining whether the first device is connected to a second device, the second device located between the first device and the gateway; means for in response to determining that the first device is disconnected from the second device, selecting a target device from one or more candidate devices in the network, each of the candidate devices being connectable to the gateway; and means for establishing a connection with the target device for reestablishing the connection to the gateway.

In some embodiments, the apparatus further comprises: means for determining at least one of the following: link quality with each candidate device, a frequency band used by each candidate device.

In some embodiments, the means for selecting the target device from the set of candidate devices comprises: means for transmitting, to a third device, information indicating that the first device is to reestablish the connection the gateway, the third device connecting to the gateway via the first device; means for receiving, from the third device, an identity of the third device; and means for selecting the target device from the candidate devices, such that the target device has a further identity different from the identity of the third device.

In some embodiments, the means for establishing the connection with the target device for reestablishing the connection to the gateway comprises: means for in response to determining a channel used for connecting to the target device is a dynamic frequency selection (DFS) channel, determining whether the channel is enabled at the first device; means for in response to the channel is enabled, establishing the connection with the target device.

In some embodiments, the apparatus further comprises: means for in response to that the channel is disabled, selecting, from the candidate devices, a further target device for re-establishing the connection to the gateway.

In some embodiments, the means for establishing the connection with the target device for reestablishing the connection to the gateway comprises: means for obtaining a channel available to the target device; and means for transmitting, to a fourth device, a channel switching request to cause the fourth device switching to the channel, the fourth device connecting to the gateway via the first device.

Fig. 7 is a simplified block diagram of a device 700 that is suitable for implementing embodiments of the present disclosure. The device 700 may be implemented at the device 420. As shown, the device 700 includes one or more processors 710, one or more memories 720 coupled to the processor (s) 710, one or more transmitters and/or receivers (TX/RX) 740 coupled to the processor 710.

The processor 710 may be of any type suitable to the local technical network, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 700 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

The memory 720 may be of any type suitable to the local technical network and may be implemented using any suitable data storage technology, such as a non-transitory computer readable storage medium, semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory, as non-limiting examples.

The memory 720 stores at least a part of a program 730. The TX/RX 740 is for bidirectional communications. The TX/RX 740 has at least one antenna to facilitate communication, though in practice an Access Node mentioned in this application may have several ones. The communication interface may represent any interface that is necessary for communication with other network elements.

The program 730 is assumed to include program instructions that, when executed by the associated processor 710, enable the device 700 to operate in accordance with the embodiments of the present disclosure, as discussed herein with reference to Fig. 6. That is, embodiments of the present disclosure can be implemented by computer software executable by the processor 710 of the device 700, or by hardware, or by a combination of software and hardware.

While this specification contains many specific implementation details, these should not be construed as limitations on the scope of any disclosure or of what may be claimed, but rather as descriptions of features that may be specific to particular embodiments of particular disclosures. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable sub-combination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a sub-combination or variation of a sub-combination.

Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the embodiments described above should not be understood as requiring such separation in all embodiments, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products.

Various modifications, adaptations to the foregoing exemplary embodiments of this disclosure may become apparent to those skilled in the relevant arts in view of the foregoing description, when read in conjunction with the accompanying drawings. Any and all modifications will still fall within the scope of the non-limiting and exemplary embodiments of this disclosure. Furthermore, other embodiments of the disclosures set forth herein will come to mind to one skilled in the art to which these embodiments of the disclosure pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings.

Therefore, it is to be understood that the embodiments of the disclosure are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are used herein, they are used in a generic and descriptive sense only and not for purpose of limitation.

Claims

A device, comprising:

at least one processor; and

at least one memory including computer program codes;

the at least one memory and the computer program codes are configured to, with the at least one processor, cause the device at least to:

in response to losing a connection between a first device and a gateway in a network, determine whether the first device is connected to a second device, the second device located between the first device and the gateway;

in response to determining that the first device is disconnected from the second device, select a target device from one or more candidate devices in the network, each of the candidate devices being connectable to the gateway; and

establish a connection with the target device for reestablishing the connection to the gateway.
The device of claim 1, wherein the device is further caused to:

determine at least one of the following:

link quality with each candidate device,

a frequency band used by each candidate device.
The device of claim 1, wherein select the target device from the set of candidate devices comprises:

transmit, to a third device, information indicating that the first device is to reestablish the connection the gateway, the third device connecting to the gateway via the first device;

receive, from the third device, an identity of the third device; and

select the target device from the candidate devices, such that the target device has a further identity different from the identity of the third device.
The device of claim 1, wherein establish the connection with the target device for reestablishing the connection to the gateway comprises:

in response to determining a channel used for connecting to the target device is a dynamic frequency selection (DFS) channel, determine whether the channel is enabled at the first device;

in response to the channel is enabled, establish the connection with the target device.
The device of claim 4, wherein the device is further caused to:

in response to that the channel is disabled, select, from the candidate devices, a further target device for re-establishing the connection to the gateway.
The method of claim 1, wherein establish the connection with the target device for reestablishing the connection to the gateway comprises:

obtain a channel available to the target device; and

transmit, to a fourth device, a channel switching request to cause the fourth device switching to the channel, the fourth device connecting to the gateway via the first device.
A communication method, comprising:

in response to losing a connection between a first device and a gateway in a network, determining whether the first device is connected to a second device, the second device located between the first device and the gateway;

in response to determining that the first device is disconnected from the second device, selecting a target device from one or more candidate devices in the network, each of the candidate devices being connectable to the gateway; and

establishing a connection with the target device for reestablishing the connection to the gateway.
The method of claim 7, further comprising:

determining at least one of the following:

link quality with each candidate device,

a frequency band used by each candidate device.
The method of claim 7, wherein selecting the target device from the set of candidate devices comprises:

transmitting, to a third device, information indicating that the first device is to reestablish the connection the gateway, the third device connecting to the gateway via the first device;

receiving, from the third device, an identity of the third device; and

selecting the target device from the candidate devices, such that the target device has a further identity different from the identity of the third device.
The method of claim 7, wherein establishing the connection with the target device for reestablishing the connection to the gateway comprises:

in response to determining a channel used for connecting to the target device is a dynamic frequency selection (DFS) channel, determining whether the channel is enabled at the first device;

in response to the channel is enabled, establishing the connection with the target device.
The method of claim 7, further comprising:

in response to that the channel is disabled, selecting, from the candidate devices, a further target device for re-establishing the connection to the gateway.
The method of claim 7, wherein establishing the connection with the target device for reestablishing the connection to the gateway comprises:

obtaining a channel available to the target device; and

transmitting, to a fourth device, a channel switching request to cause the fourth device switching to the channel, the fourth device connecting to the gateway via the first device.
An apparatus, comprising:

means for in response to losing a connection between a first device and a gateway in a network, determining whether the first device is connected to a second device, the second device located between the first device and the gateway;

means for in response to determining that the first device is disconnected from the second device, selecting a target device from one or more candidate devices in the network, each of the candidate devices being connectable to the gateway; and

means for establishing a connection with the target device for reestablishing the connection to the gateway.
The apparatus of claim 13, further comprising:

means for determining at least one of the following:

link quality with each candidate device,

a frequency band used by each candidate device.
The apparatus of claim 13, wherein the means for selecting the target device from the set of candidate devices comprises:

means for transmitting, to a third device, information indicating that the first device is to reestablish the connection the gateway, the third device connecting to the gateway via the first device;

means for receiving, from the third device, an identity of the third device; and

means for selecting the target device from the candidate devices, such that the target device has a further identity different from the identity of the third device.
The apparatus of claim 13, wherein the means for establishing the connection with the target device for reestablishing the connection to the gateway comprises:

means for in response to determining a channel used for connecting to the target device is a dynamic frequency selection (DFS) channel, determining whether the channel is enabled at the first device;

means for in response to the channel is enabled, establishing the connection with the target device.
The apparatus of claim 13, further comprising:

means for in response to that the channel is disabled, selecting, from the candidate devices, a further target device for re-establishing the connection to the gateway.
The apparatus of claim 13, wherein the means for establishing the connection with the target device for reestablishing the connection to the gateway comprises:

means for obtaining a channel available to the target device; and

means for transmitting, to a fourth device, a channel switching request to cause the fourth device switching to the channel, the fourth device connecting to the gateway via the first device.
A computer readable medium storing instructions thereon, the instructions, when executed by at least one processing unit of a machine, causing the machine to perform the method according to any one of claims 1-12.