Description:TECHNICAL FIELD
[0001] The present disclosure relates to the field of wireless communication. In particular, the present disclosure relates to a system and a method for performing recovery operations in a network.

BACKGROUND
[0002] Significant developments in Mobile Ad Hoc Networks (MANETs) and networking radios have occurred, resulting in self-configuring networks without a single point of failure. The MANETs continually monitor, update, and propagate connectivity information (CIF) among radios. In Time Division Multiple Access (TDMA) networks, slots are crucial for collision-free data transfer, and a dedicated set of radios forms the backbone, calculated based on minimum CDSs.
[0003] The conventional methods perform link quality analysis and calculate the route according to an on-demand reactive routing protocol. The framework of the on-demand routing protocol does not ensure Quality of Service (QoS) provisioning. Radios have to contend for transmission, leading to delays for each radio in the delivery of packets. An alternate path is selected using the route discovery scheme in response to the link quality analysis. However, the path may not be valid if the network changes rapidly or abruptly during data transfer. If an alternate path is selected from a set of paths calculated based on previous route discovery, the selected path may not reflect the current changes in topology.
[0004] Therefore, there is a need to address the drawbacks mentioned above and any other shortcomings, or at the very least, provide a valuable alternative to the existing systems and methods.

OBJECTS OF THE PRESENT DISCLOSURE
[0005] A general object of the present disclosure relates to an efficient and reliable system and method that efficiently obviates the above-mentioned limitations of existing systems and methods.
[0006] An object of the present disclosure relates to a system and a method for recovering a node that is isolated from a network, thereby enhancing network resilience by efficiently restoring connectivity to nodes that have become isolated.
[0007] Another object of the present disclosure relates to a system and a method for establishing an independent network using a plurality of nodes isolated from a network during recovery operations, thereby enabling a data transfer even if a main network becomes failure.
[0008] Yet another object of the present disclosure relates to a system and a method for merging multiple networks using distinct network identities when the multiple networks are in proximity to each other, thereby enhancing network consolidation capabilities.

SUMMARY
[0009] An aspect of the present disclosure relates to a method for robust network recovery in a time division multiple access (TDMA) based Mobile Adhoc Network (MANET). The method includes selecting backbone radios for connecting a plurality of radios in the network and enabling the plurality of radios to mark the existence of the plurality of radios in network based on detection of arbit information packet (AIP) sent periodically by an arbitrator. Further, the method includes upon separation of a single radio within the network, separated single radio selects forwarder to transmit miss request of AIP to the arbitrator. Further, the method includes upon loss of connection by the plurality of radios within network, fast recovery sub-module and slow recovery sub-module differentiated by respective recovery start times. Further, the method includes merging two networks with distinct network identifiers (IDs) when corresponding networks come in close proximity and fall within the listening range.

BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 illustrates an example block diagram of a system for performing network recovery operations and network merge operations in a network, in accordance with embodiments of the present disclosure.
[0011] FIG. 2A illustrates schematic representation of random topology of a network, in accordance with embodiments of the present disclosure.
[0012] FIG. 2B illustrates schematic representation of a CDS, in accordance with embodiments of the present disclosure.
[0013] FIG. 2C illustrates schematic representation of an operating state of radios in the network, in accordance with embodiments of the present disclosure.
[0014] FIG. 3A illustrates schematic representation of recovering multiple radios in the network when a centralized radio is isolated, in accordance with embodiments of the present disclosure.
[0015] FIG. 3B illustrates schematic representation of a network split due to link breakage between the radios, in accordance with embodiments of the present disclosure.
[0016] FIG. 4 illustrates flow chart of a method for recovering the network based on slow recovery operation, in accordance with embodiments of the present disclosure.
[0017] FIG. 5 illustrates schematic representation of merging networks, in accordance with embodiments of the present disclosure.
[0018] FIG. 6 illustrates a flow chart of an example method for robust network recovery in time division multiple access (TDMA) based Mobile Adhoc Network (MANET), in accordance with embodiments of the present disclosure.

DETAILED DESCRIPTION
[0019] Embodiments explained herein relate to wireless communication. In particular, the present disclosure relates to a system and a method for performing recovery operations in a network.
[0020] The present disclosure may relate to a framework that accommodates the path discovery technique proactively based on the CIF, reflecting the current link failure and radio mobility in the mobile environment. The chosen path should be optimum and the shortest to avoid compromising the total network throughput. The framework must enable the radio to quickly select an updated path based on link failure and radio mobility. Additionally, the framework may rely on CIF exchange, which reflects changes in topology due to radio mobility, channel conditions, battery drainage, and other factors. This CIF is crucial for choosing an optimal path for data exchange and selecting the network backbone for exchanging CIF. However, the exchange of CIF involves the flow of control information in the network. The loss of control information triggers the process of network recovery for radios in the network. The present disclosure may relate to a method for robust network recovery in Time Division Multiple Access (TDMA)-based Mobile Ad Hoc Network (MANET). The method may adapt to link failures caused by mobility, channel conditions, battery drainage, or any other conditions. This method may eliminate radios that experience packet loss due to weak links from being part of the relay radios. The information loss of radios necessitates the reconstruction of the network backbone with updated connectivity. This method may describe various recovery processes used to reconstruct the network backbone based on the updated connectivity. The recovery process differentiated based on number of radios are termed single radio, multi radio network recovery. The network recovery process may be fast or slow based on the time taken by each process. Fast recovery begins at the onset of the loss of AIP. A role-based, non-overlapping recovery opportunity is assigned to each radio to avoid collisions and expedite the recovery process. The end of fast recovery is marked by the total recovery time of the network. Slow recovery. Starts when the fast recovery process fails. The slow recovery process may involve assigning recovery attempts using CIF updated based on active listening of radios in the network. If two or more independently formed networks come closer to the listening range of each other, the process of network merge is initiated, leading to a combined network. The methods disclosed here help automatically recover the network in case of any radio failure.
[0021] In exemplary embodiments, the MANET may be an ad-hoc network of mobile radios that does not rely on any fixed infrastructure for communication, unlike satellite or cellular communication. Any radio may dynamically configure itself based on the mobility of radios in the network. Each radio may be characterized by two identities assigned dynamically through the network joining process. A Soft ID (SID) is the identity assigned from a consecutive set of integers based on the order in which the radio joins. Each network is identified by a unique identity called the network identity (NWID), which remains the same for all radios in a given network.
[0022] In an embodiment, there is a control information flow in the network, which may discover and maintain the possible links or connectivity between the radios in the network. Hence, every radio is aware of the overall connectivity of the radios in the network, which is updated and maintained in every frame. An entity is selected from among all connected radios in the network by calculating the connected dominating set(CDS), which constitutes the backbone of the network, and every other radio is connected to backbone From among the radios of the CDS lies the controller for the network, termed the arbitrator. The arbitrator is chosen based on selection factors like maximum connectivity, critical position in the topology, and other factors. The remaining radios in the CDS, other than the arbitrator, are called the leaf radios. In exemplary embodiments, every radio may be updated about the global network connectivity by the arbitrator, which is broadcasted to every radio via leaf radios. The global network connectivity may be globally updated by all radios. This global connectivity may enable radios to calculate an optimum path to a destination for the transfer of data when required. The global connectivity may enhance that all radios update their CIF at every frame, due to the mobility of radios in the network. This may enable the radios to choose the optimum path based on updated CIF and enables them to choose an alternate path within a frame.
[0023] However, any radio missing this control information of global network connectivity identifies a possible cause of link failure or battery drainage of the radio in the path to the arbitrator. This identification process at every radio may initiate a possible single radio network recovery if the radio continues to listen to active transmission of control information from its neighbours identified using the packet type. If every radio fails to listen to active transmission within the network, each may initiate a possible opportunity for recovery after confirming the isolation for a few frames. In this process of recovery termed as fast recovery, there is a non-overlapping prioritized opportunity of recovery for every radio in the network. Any radio successful in recovering the network may close the recovery process by choosing the arbitrator and leaf radios of the reconstructed network, with every radio being informed of its network CIF. If this process of recovery results in a separate sets of radios without any communication in between, multiple networks each with a unique identity is the result, called the network split. In the process, the individual identity of the radio is still retained but, the split network maintains different network identities to identify as separate networks. If fast recovery process which is limited by the total network recovery time fails, the slow recovery process starts. All these processes involving the reconstruction of the network are termed network recovery. However, there is a provision for the radio to permanently depart the network by sending a message. In this process, the identity of the radio is made available to a new radio joining the network. The network previously split, or two independently formed networks moving closer to the listening range, invokes the possibility of a merge.
[0024] In some embodiments, the MANET is a network of mobile radios capable of forming and maintaining the network, enabling the exchange of voice, data, and videos. A Media Access Control (MAC) protocol for MANET specified here is dynamic TDMA. The selection of an arbitrator suited to the dynamically varying conditions of the channel is crucial in the MANET scenario. This requires global CIF to be available to all radios in the network. In an embodiment, a network is well defined by certain parameters such as network identity (NWID), network size (NWSZ), hard identity (HID), soft identity (SID), operating roles (ORL), and the global network connectivity of radios in the network This facilitates adaptability of radios to changing roles due to alterations in connectivity. In an embodiment, ORL of each radio may vary between the arbitrator, the leaf radio, and the end radio based on attributes such as additions or deletions of radios, changes in topology, battery drainage, or power-off of the arbitrator, packet drops, alike and not limited to movement of each radio associated with each user and position of each radio with respect to other radios in the network.
[0025] In some embodiments, the network may be identified by a unique identification number, which is distinct for each given network. No two networks share the same identity, as each radio possesses a unique HID, and the NWID is directly linked to the HID. This exclusive identification number is referred to as the NWID. The NWSZ represents the total number of radios in the network. Every radio in a network is assigned two unique identification numbers. The HID specifies the hardcoded identification number of a radio, ensuring uniqueness regardless of the network. The SID is dynamically assigned to a radio based joining time and the current NWSZ. Any action leading to the merge of separate networks into a new network triggers the update of NWSZ, NWID, and SID, while the HID remains constant. In an embodiment, the radios in the network are broadly classified as arbitrator, leaf radio, and end radio based on the roles taken. Each radio updates and sends neighbourhood CIF in fixed slots every frame. The leaf radios have the additional role of relaying the CIF of their neighbour radios not directly connected with the arbitrator to the arbitrator. The arbitrator has the additional role of consolidating the CIF to define roles for all radios in the network based on the global network connectivity and broadcasts the information. The control slot used by the arbitrator for the broadcast is called the AIP. The remaining radios without any additional roles are called the end radios.
[0026] In some exemplary embodiments, the roles of the radio in the network are defined based on the topology of the network and the computation of the CDS of the topology. Any radio can assume any role based on the topology, link quality, and other related factors. The network's arbitrator calculates the connected dominating set (CDS) of the topology using global network CIF. The CDS acts as the backbone of the network, through which information flows. The CDS may include the leaf radios and the arbitrator. An end radio in the network is connected to the backbone, facilitating information flow. In some embodiments, there is a bidirectional information flow, updated every frame. The information flow may be described here follows a specific transmission order. All information to the arbitrator follows the leaf-to-root transmission order (L2R); the root, in this context, is the arbitrator of the network. The flow of information from end node to root node through leaf node is called the L2R transmission order. All The information from the arbitrator follows the root-to-leaf transmission order (R2L). This flow of information from root node to end node through leaf node is called the R2L transmission order. All network management information follows this order.
[0027] In an embodiment, the global network CIF may follow the R2L transmission order to make it available to all radios in the network. It may be critical for all the radios to update the global network CIF to adapt to changes in network topology due to the mobility or addition of radios. The global network CIF is locally used by every radio to calculate the optimum path to any radio for the transfer of data. Various embodiments with respect to the present disclosure will be explained in detail with reference to FIGs.1to5.
[0028] FIG. 1 illustrates an example block diagram of system 102for performing network recovery operations and network merge operations in a network, in accordance with embodiments of the present disclosure.
[0029] Referring to FIG. 1, the system 102 may include one or more processors 104, a memory 106, an interface(s) 108, and a processing engine(s) 110. The memory 106 operatively coupled with the one or more processors 104, where the memory 106 may include one or more instructions which, when executed, cause the one or more processors (104) to perform network recovery operation and network merge operation. The processing engine(s) 110 may include a selection module 114, a detection module 116, a single radio network recovery module 118, a multi radio network recovery module120, a network merge module 122 and other module(s) 124.The other module(s) 124 may implement functionalities that supplement applications/functions performed by the processing engine(s) 110.The database 112 may include data that is either stored or generated as a result of functionalities implemented by any of the components of the processing engine(s) 110.In an embodiment, the selection module 114 may be configured to select backbone radios for connecting a plurality of radios in a network to transmit information to the plurality of radios. In an embodiment, the detection module 116 may enable the plurality of radios to mark the existence of the plurality of radios in the network based on detection of AIP sent periodically by an arbitrator. In an embodiment, the single radio network recovery module 118 may select a forwarder to forward a miss request of the AIP to the arbitrator upon separation of a single radio from the plurality of radios within the network by selecting a forwarder. In an embodiment, the multi radio network recovery module120 may include a fast recovery sub-module and a slow recovery sub-module differentiated by respective recovery start times upon loss of connection by the plurality of radios within the network. In an embodiment, the network merge module 122 may merge two networks with distinct network identifiers (IDs) when corresponding networks come in close proximity and fall within the listening range, thereby collectively facilitating automatic recovery and maintenance of the network in the event of any radio failure.
[0030] FIG. 2A illustrates schematic representation 200Aof random topology of a network, in accordance with embodiments of the present disclosure. FIG. 2B illustrates the schematic representation 200B of a CDS, in accordance with embodiments of the present disclosure. FIG. 2C illustrates the schematic representation 200C of an ORL of radios in the network, in accordance with embodiments of the present disclosure. Referring to FIG. 2A, a random topology of 8 radios with SID 0 to 7. The numbers marked 1 to 8 within the node in the figure represents the HID. This representation of HID may be used to simplify the depiction in the figure, as the HID value is generally long, extending up to 32 bits. The random topology as illustrated in FIG. 2Amay be represented using the CDS shown in FIG. 2B, where radio 6 may serve as the arbitrator, and radio 2 and radio 7 function as leaf radios. FIG. 2Crepresents the roles assumed by the radios in the network: The radio 6 as the arbitrator (A), radio 2 as the first leaf radio (L1), and radio 7 as the second leaf radio (L2). The remaining radios such as radio 1, radio 8, radio 4, radio 3, and radio 5 are end radios indicated by E1, E2, E3, E4, and E5, respectively. The transmission order from the arbitrator to the leaf, denoted as R2L, according to FIG. 2B, is radio 6, radio 7, and radio 2. The size of R2L, or the total number of radios in the CDS (M), is equal to 3.
[0031] In an embodiment, every radio may require information broadcasted by the arbitrator in the AIP to confirm its existence within the network. Any radio losing this information tries to regain network access by requesting re-entry if each radio identifies any active radio in neighbourhood with the same NWID. At any instant, either single radio or multiple radios may lose track of their parent network due to the loss of the AIP. Single radio separation occurs due to the movement of a single radio beyond the listening range of other connected radios in the network. Multiple radio (separation may occur due to the power-off or link breakage of crucial radios, such as arbitrators or leaf radios, in the network. If an arbitrator or leaf radio is powered off or if the link is weak, may lead to a situation where all radios or at least a few are left without any communication from the arbitrator, resulting in the absence of a network. The process of reconstruction of network in such scenario is termed recovery.
[0032] In an embodiment, the single radio recovery may be initiated due to single radio separation and entry into the network. This may be due to a single radio losing track of the network temporarily and later regaining the network due to the mobility of radios or due to channel errors. A forwarder is chosen to forward the request to the arbitrator through leaf radios., If the single radio separated has partial information about the network., it requests only partial sensitive information, namely CIF, which is updated once in every frame. Based on information such as CIF and the NWSz, the radio may request possible missing information. With their pre-existing identities retained. In some embodiments, the SID of the departed radio is preserved in the network, enabling the radio to gain access to the network with SID. The process may involve the departed radio choosing an active radio as forwarder based on listening. The radio sends a miss request of AIP. The forwarder forwards this request to the arbitrator, who verifies the identities of the radio and grants entry by sending the AIP, which is then forwarded.
[0033] In an embodiment, the multi-radio network recovery is the set of procedures involved in the recovery of departed radios, specifically in situations where there is no arbitrator to control the network. This scenario may occur for various reasons, such as the arbitrator leaving the network due to the radio's mobility, or the arbitrator being powered off. The arbitrator may assign possible roles to radios based on the updated topology in each frame, potentially selecting a new arbitrator for the next frame. This information may be transmitted using an AIP, miss of which result in state where there is no arbitrator. The recovery process is essential for radios to regain network connectivity based on the available information in such scenario. There are two types of recovery processes a fast recovery (e.g., a first recovery operation) and a slow recovery (a second recovery operation).
[0034] In some embodiments, the fast recovery is a technique used to recover the network immediately based on the previous history of the network. Every radio in the network maintains a record of the recovery opportunities based on its role. The arbitrator may get the highest opportunity, followed by leaf radios and end radios. Among the leaf radios, the opportunity is based on their proximity to the arbitrator, with leaf radios closer to the arbitrator having a higher opportunity, followed by the next closer radios, and so on. Among the end radios, the recovery opportunity may be based on their SID, with smaller SID taking preference over higher SID. This type of opportunity distribution may prevent radios from attempting parallel recovery. In an embodiment, every radio maintains a record of the network connectivity and the recovery opportunities of all radios, which are updated every frame and are available with the radio prior to departure. The recovery opportunity of radios is quantified by a factor called the "frame differing period (FDP)," which measures the number of frames the radio differs before initiating a recovery. The radio with the first opportunity may have the lowest FDP, and the radio with the last opportunity may have the highest FDP. Every radio gets at least opportunities for recovery. If the radio fails for all attempts, the next candidate gets the opportunity based on the FDP (e.g., a time interval). In all these attempts, the radio takes the role of an arbitrator and initiates recovery. In each attempt, the radio uses the network connectivity history to find the new arbitrator by eliminating the entries of those who have exhausted their opportunity of recovery .The recovering radio broadcasts AIP to enable the nodes to update connectivity and roles of the recovered network. If a radio fails to recover in all attempts, the next node gets the opportunity based on the priority. The radio wise priorities expressed in FDP are maintained by all radios. The number of recovery attempts per radio; and number of frames to confirm the possible opportunity of recovery, ; accordingly is calculated in terms of number of frame differs by any radio based on the roles taken by the radios according to (1) ,(2) and (3). The number of attempts of recovery immediately following the frame differ period of a given radio is . Addition of recovery attempt to recovery opportunity of the last radio matches with the total recovery time of the network according to (4); which marks the end of fast recovery process
[0035] The recovery opportunity or the FDP of radio whose SID is is given by

(1)


(2)


(3)
[0036] where is the FDP of each radio whose SID is is the number of frames used to confirm the network depart. is a factor representing the number of recovery attempts per radio expressed in number of frames. The R2L is referred as the root to leaf transmission buffer which contain the SID of leaf radios and arbitrator in appropriate index based on the transmission order starting from the arbitrator. is the index of the leaf radio or the arbitrator in R2L transmission buffer. is the size of R2L which is the total number of radios in the CDS containing leaf radios and arbitrator. The total recovery time of the network is given by

(4)
[0037] where the maximum recovery time of the network in terms of number of frames; N is the network size. The maximum recovery time is reached only if none of the radios were successful in recovering the network.
[0038] FIG. 3A illustrates schematic representation 300Aof recovering multiple radios in a network when a centralized radio is isolated, in accordance with embodiments of the present disclosure. Referring to FIG. 3A, two distinct cases of multi-radio network recovery where the arbitrator, namely radio 6, is powered off, invoking a fast recovery as depicted in FIG. 3A. All radios in the network wait for to confirm network disintegration. The Arbitrator has the first opportunity, with no attempts as it is which is switched off. At the end of 8 frames, radio 7 may get the opportunity for recovery, during which the radio 7 may erase all possible connectivity of radio 6. At this moment, radio 7 may take the role of arbitrator and initiates recovery based on the updated connectivity. The new connectivity may resemble that of FIG. 3A, with radio 3 becoming the new arbitrator, and radio 2, radio 4, radio 5, and radio 7 becoming the new leaf radios. The information is then broadcasted to all radios in the network; radios receiving this information may tune to this update and new roles. This is a clear illustration of the fast recovery of the network. If radio7 fails in recovering the network, as the new arbitrator radio3 has somehow not received the recovery information, radio7 still attempts recovery by removing all the connectivity of radio3. If radio7 exhausts the four opportunities of recovery, the next candidate is radio2, followed by radio1, radio4, radio3, radio5, and radio8. If recovery is not ensured despite all attempts, fast recovery ends and the slow recovery begins.
[0039] FIG. 3B illustrates the schematic representation 300B of a network split due to link breakage between the radios, in accordance with embodiments of the present disclosure. Referring to FIG. 3B, multi radio network recovery, depicting a portion of a network that has experienced a split, resulting in two distinct networks, NW1 and NW2. In this scenario, the link connecting radio2, with radio6, and radio4 with radio3 is broken. Notably, the NW2 portion of the network, where the arbitrator is still operational, remains intact with updated connectivity. Conversely, the NW1 portion of the network may be separated due to the loss of the arbitrator. Consequently, this portion initiates a recovery process to reform an intact network, NW1. The NW1 segment undergoes a fast recovery, with radio2 seizing the recovery opportunity in the 12th frame. During this process, radio2 removes the connectivity entries of both radio7 and radio6 from the connectivity history, ensuring connectivity to NW1, with radio2 acting as the arbitrator. NW1 becomes active in the subsequent frame, with radio2 disseminating information to the remaining radios, radio1 and radio4.If all radios have exhausted their opportunities for recovery and the network is not yet recovered, the slow recovery process begins. In the slow recovery process, the history of connectivity and recovery opportunities used during fast recovery is invalid. The recovery is termed 'slow' as it is initiated only after all radios have had an opportunity for recovery, and their FDP count exceeds the total recovery time. At this point, radios clear their CIF and listen for any other transmissions to update their network identities. In an embodiment, any radio failing to listen to any transmissions within predefined time limit, may update its NWID obtained from the HID In some embodiments, any radio failing to listen to transmissions with the same NWID, if listens to another radio in the recovery state whose NWID is lower than its own, may update the NWID to the lowest. In exemplary embodiment, any radio listening from any active network may adjust the NWID to the identity of the active network. In some embodiments, the updating of the NWID may be followed by the recovery process if there exist at least two radios with the same NWID. Among the radios with the same NWID, the one with the lowest SID gets the opportunity to initiate the recovery process. In contrast if any radio that identifies an active network during this process, tunes its NWID and places a request to be a part of the tuned network, which is approved by the arbitrator of that network. In the onset of slow recovery, all the radios will reset their connectivity history and radio wise opportunity information. Each radio updates the connectivity based on listening within the same NWID, with the smallest SID getting the opportunity for initiating recovery.
[0040] FIG. 4 illustrates flow chart of a method 400 for recovering the network based on slow recovery operation, in accordance with embodiments of the present disclosure. Referring to FIG. 4, a radio may obtain the opportunity for recovery, initiates the recovery process by assuming the role of arbitrator and updates a connectivity, calculates the backbone based on listening, and sends the AIP. The radios acknowledge the receipt of the AIP, completing the slow recovery process. In some embodiments, all the recovery schemes, SID and HID, of the radio departing from the network due to link breakage or power off are preserved indefinitely by all the radios in the network. This may prevent any new radio with a different HID, who is no longer a part of the network, from entering the network, especially when the NWSZ has reached the maximum capacity. In an embodiment, the identity of departing radios may be released from the network which enables any new radio to enter the network using the released identity if the network size has reached the maximum capacity. For releasing the radio identity, any radio in the network wishing to leave a network permanently may send a request. Any radio realizing own departure or any radio that may authorize the departure of any radio can send the request. The request is forwarded to the current arbitrator of the network through the leaf radios. The arbitrator approves the request and commands all the radios active in the network to release the SID and HID of the radio departing or radio which has already departed the network. This information is sent by the arbitrator to all the radios through the leaf radios in AIP. Referring to FIG. 4, in some exemplary embodiments, at step 402, the radio listen neighbourhood. At step 404, the radio determines whether any nearby radio is detected. At step, 406, the radio may update NWID to the HID if no nearby radio is detected. At step 408, the radio determine whether the NWID is same if the nearby radio is detected. At step 410, the radio may determine whether NWID is least among nearby radio if the NWID is not same. At step 412, the radio update NWID to the least if the NWID of the radio is not least. At step 414, the radio may determine whether there is an active network if the NWID is same. At step 416, the radio may determine whether the SID is least. At step 418, the radio may wait for recovery packet of the SID is not least. At step 420, the radio may determine that the recovery packet is received. At step 422, the radio may initiate single entry process if there is the active network is detected. At step 424, the radio may send recovery packet to the active network as represented in step 426 if the SID is the least
[0041] In some embodiments, two or more distinct networks, each with different NWID, if they come closer to the listening range of each other, invoke a potential opportunity for network merging. Merging entails the exchange of NWSZ, SID, HID, and CIF of each network to consolidate overall network details with respect to their identity and connectivity. One of the radios at the boundary of two networks is a possible initiator of the merge. Consent from the arbitrator of either network is required for merging. The radio from the other network is chosen to forward the merge request to the arbitrator; the same radio informs the merge initiator about the confirmation by its arbitrator. Upon receiving the confirmation, the merging process gets initiated. The process of merging involves the following set of procedures such as any radio that listens to an active transmission from another network becomes a potential candidate for merge initiation. Each radio, based on the NWID, assumes itself to be the initiator, and the one with the least NWID takes the role of the merge initiator. Following this, the merge initiator may select forwarders from either network to transmit the merging request to the relevant arbitrators. The arbitrators then grant consent (e.g., a response message) to the merging request in their respective networks. The forwarders may relay the consent, connectivity and network information of the concerned network to the initiator. At this stage, the arbitrators of both networks freeze their roles for a predetermined time, allowing the initiator to assume the role of arbitrator. The initiator reconstructs the network in terms of connectivity and identity, redefines roles based on the reconstructed connectivity, and selects a new arbitrator. The comprehensive information processed by the initiator in this step is broadcasted to all radios in either network. Upon receiving this broadcast, radios tune to the new merged NWID, adopting roles as assigned by the initiator. In some embodiments, in networks uniquely distinguished by their network identities, each network operates with a distinct reference clock for synchronization. However, the use of different reference clocks increases the likelihood of collisions during packet exchanges between these networks. To mitigate this issue, the reference clock time of the network, other than the one initiating the merge, is carefully adjusted based on timing information provided by the initiator. This adjustment allows all radios in the other network to coarsely synchronize their time, resolving potential collisions for crucial packets exchanged during the network merge process. Furthermore, the newly selected arbitrator, determined through the merged network, becomes the new clock reference. This enables all radios in the merged network to finely tune their time, ensuring a harmonized and synchronized operation
[0042] FIG. 5 illustrates schematic representation 500 of merging networks, in accordance with embodiments of the present disclosure.
[0043] Referring to FIG. 5, a merging of two independent networks (e.g., a first network and a second network) facilitated by an active link between radios 4 and 6. The radios 4 and 6 listen to NW2 and NW1, respectively. Since NWID1 < NWID2, radio 4 seizes the opportunity to initiate a merger. The radio 4 may designate radio 2 as the forwarder from the own network and radio 6 as the forwarder from the other network. As arbitrators of their respective networks, both radios grant consent for the network merging process. Acting as the forwarder of NW2, radio 6 transmits the complete network information and connectivity to radio 4. Subsequently, the radio 4 may consolidate the own network and connectivity information with that received from the other network, creating an updated connectivity and calculating a new backbone based on this information. The newly formed backbone may be broadcasted to all radios in the network. All radios receiving the merger confirmation message and the enhanced topology, connectivity, and network information update themselves to adopt the new NWID and topology. In some embodiments, the methods may describe in this present disclosure may enable the reconstruction of network based on topology and eliminate the radios which have packet loss due to weak links from being part of the backbone of the network. The methods adapt to link failure due to mobility, channel condition, battery drainage or any other conditions. The methods disclosed here helps to automatically recover and maintain the network in case of any radio failure. In some exemplary embodiments, each radio may include a selection module, a keep alive detection module 116, a single radio network recovery module, a multi radio network recovery module 120, and a network merge module 122. The selection module may be configured to select the backbone radios. In an embodiment, the selection module may be is configured to select the backbone radios, which connects all the other radios in the network. The back bone radios ensure that information passing through it reaches all radios in the network. The keep alive detection module 116 may enable all other radios to mark its existence in the network. In an embodiment, the keep alive detection module 116 may be configured to designate an arbitrator which is part of the backbone network to send AIP periodically. The keep alive detection module 116 may be configured to enable all other radios to mark its existence in the network based on the detection of this AIP The single radio network recovery module 118 may be configured in the event, when a radio loses connection with the network for an intermittent period and regains the connection back again. The multi radio network recovery module 120 may be configured in the event, when multiple radios loose connection with the network. This module constitutes a fast recovery sub-module and a slow recovery sub-module differentiated by the recovery start time. The network merge module 122 may be configured to merge two networks, with distinct NWIDs when it comes closer and is in the listening range.
[0044] FIG. 6 illustrates a flow chart of an example method 600 for robust network recovery in time division multiple access (TDMA) based Mobile Adhoc Network (MANET), in accordance with embodiments of the present disclosure.
[0045] Referring to FIG. 6, at block 602, the method 600 may include selecting, by a selection module 114, backbone radios for connecting a plurality of radios in a network to transmit information to the plurality of radios. At block 604, the method 600 may include enabling, by a detection module 116, the plurality of radios to mark the existence of the plurality of radios in the network based on detection of AIP sent periodically by an arbitrator. At block 606, implementing a single radio network recovery module 118, upon separation of a single radio from the plurality of radios within the network, the separated single radio selects a forwarder to transmit a miss request of the AIP to the arbitrator through the forwarder. At block 608, the method 600 may include implementing a multi radio network recovery module 120, upon loss of connection by the plurality of radios within the network, the multi radio network recovery module 120 includes a fast recovery sub-module and a slow recovery sub-module differentiated by respective recovery start times. At block 610, the method 600 may include utilizing a network merge module 122 to merge two networks with distinct network identifiers (IDs) when corresponding networks come in close proximity and fall within the listening range, thereby collectively facilitating automatic recovery and maintenance of the network in the event of any radio failure.

ADVANTAGES OF PRESENT DISCLOSURE
[0046] The present disclosure provides system and a method for enhancing network resilience by efficiently restoring connectivity to nodes that have become isolated.
[0047] The present disclosure provides system and a method for enabling a data transfer even if a main network becomes failure.
[0048] The present disclosure provides system and a method for enhancing network consolidation capabilities.
, Claims:1. A method (600) for robust network recovery in time division multiple access (TDMA) based Mobile Adhoc Network (MANET), the method (600)comprising:
selecting (602), by a selection module (114), backbone radios for connecting a plurality of radios in a network to transmit information to the plurality of radios;
enabling (604), by a detection module (116), the plurality of radios to mark the existence of the plurality of radios in the network based on detection of arbit information packet (AIP) sent periodically by an arbitrator;
implementing (606) a single radio network recovery module (118), upon separation of a single radio from the plurality of radios within the network, the separated single radio selects a forwarder to transmit a miss request of the AIP to the arbitrator through the forwarder;
implementing (608) a multi radio network recovery module (120), upon loss of connection by the plurality of radios within the network, the multi radio network recovery module (120) comprises a fast recovery sub-module and a slow recovery sub-module differentiated by respective recovery start times; and
utilizing (610) a network merge module (122) to merge two networks with distinct network identifiers (IDs) when corresponding networks come in close proximity and fall within the listening range, thereby collectively facilitating automatic recovery and maintenance of the network in the event of any radio failure.

2. The method (600) as claimed in claim 1, wherein the detection module (116) is configured to designate the arbitrator within a backbone network for periodic transmission of AIP, wherein the detection module (116) is configured to facilitate the marking of the existence of the plurality of radios within the network through the detection of the AIP
3. The method (600) as claimed in claim 1, wherein the single radio network recovery module (118) configures the separated single radio to select a radio as the forwarder from a listened neighborhood list, the single radio network recovery module (118) configured to:
instruct the separated single radio to transmit the miss request of the AIP to the arbitrator through the forwarder;
configure the arbitrator to allocate TDMA slots to the forwarder, in an event of missed AIP facilitating the transmission of the AIP to the separated single radio, thereby reintegrating the separated single radio into the network.

4. The method (600) as claimed in claim 1, wherein the multi radio network recovery module (120) configures the fast recovery sub-module for role-based recovery in response to the identification of the missed AIP by the plurality of radios, wherein the multi radio network recovery module (120) configured to:
systematically assign a unique recovery start time to each radio in the network, determined by a frame differ period, wherein the frame differ period is allocated based on roles assumed by the plurality of radios prior to the detection of the missed AIP; and
generate a radio wise opportunity information about the unique recovery start time for the plurality of radios.

5. The method (600) as claimed in claim 1, wherein the fast recovery sub-module configures corresponding radios obtaining the recovery opportunity to assume the role of the arbitrator, the fast recovery sub-module configured to:
ensure multiple recovery attempts for each radio, utilizing a connectivity history in each attempt to identify a new backbone;
eliminate connectivity entries of corresponding radios whose recovery opportunities have concluded, along with the arbitrators selected in prior attempts;
instruct the selected arbitrator to transmit the AIP; and
configure other radios to acknowledge the transmitted AIP.
6. The method (600) as claimed in claim 1, wherein the multi radio network recovery module (120) configured to:
activate the slow recovery sub-module if the network fails to recover at the end of a fast recovery time;
configure corresponding radios to clear the connectivity history;
instruct corresponding radios to listen for any other transmissions to update network identities;
configure the corresponding radios with a lowest soft ID to assume the role of the arbitrator;
initiate by the selected arbitrator the recovery process by choosing the new backbone and transmitting AIP; and
configure other radios to acknowledge the transmitted AIP

7. The method (600) as claimed in claim 1, wherein the multi radio network recovery module (120) configured to establish two independent networks in the event of a group of the plurality of radios being separated from the network, and are beyond a listening range of another group identifying a network split.

8. The method (600) as claimed in claim 1, wherein the network merge module (122) is configured to merge two networks, each with distinct network IDs, when come into close proximity and fall within the listening range, the network merge module (122) in the event of network merge configured to:
assign a radio with a lower network identity, capable of listening to both networks, as the merge initiator;
configure the merge initiator to select the forwarder in both networks for forwarding a merge request to respective arbitrators;
configure the merge initiator to assume the role of the arbitrator, subject to the consent from the arbitrators of both networks;
instruct the merge initiator to consolidate information from both networks to calculate the new backbone;
transmit the AIP by the merge initiator; and
configuring other radios in the networks to acknowledge the transmitted AIP.

9. The method (600) as claimed in claim 1, wherein the detection module (116) and the network merge module (122) configured to:
identify and exclude corresponding radios with packet loss from weak links to prevent inclusion in the backbone network; and
adapt to link failures caused by factors pertaining to mobility, channel conditions, battery drainage, or other relevant conditions.

10. A system(102) for robust network recovery in a Time Division Multiple Access (TDMA) based Mobile Adhoc Network (MANET), wherein the system (102) comprises a plurality of radios, and wherein each radio comprises:
one or more processors (104);
a memory (106) operatively coupled with the one or more processors (104), wherein the memory (106) comprises one or more instructions which, when executed, cause the one or more processors (104) to:
select backbone radios for connecting a plurality of radios in a network to transmit information to the plurality of radios using a selection module;
enable the plurality of radios to mark the existence of the plurality of radios in the network based on the periodic transmission of AIP by an arbitrator using a detection module (116);
handle the recovery of a separated single radio by selecting a forwarder to send a miss request of the AIP to the arbitrator through the forwarder using a single radio network recovery module (118);
handle recovery in the event of the plurality of radios losing connection with the network, the multi radio network recovery module (120) comprising a fast recovery sub-module and a slow recovery sub-module differentiated by respective recovery start times using a multi radio network recovery module (120); and
merge two networks with distinct network IDs when the corresponding networks comes in close proximity and fall within the listening range using a network merge module (122),thereby collectively facilitating automatic recovery and maintenance of the network in the event of any radio failure.