WO2018080113A2

WO2018080113A2 - Device and method for scheduling in tsch and rpl-based industrial iot network

Info

Publication number: WO2018080113A2
Application number: PCT/KR2017/011674
Authority: WO
Inventors: 정상화; 최강훈
Original assignee: 부산대학교 산학협력단
Priority date: 2016-10-26
Filing date: 2017-10-20
Publication date: 2018-05-03
Also published as: WO2018080113A3; KR20180045590A; KR101970271B1

Abstract

The present invention relates to a device and method for scheduling in a TSCH and RPL-based industrial IoT network, wherein delay time is reduced and network efficiency is increased due to a small scheduling overhead in a TSCH and RPL-based industrial IoT network. The device includes: a parent selection management module which selects a parent node by determining network participation and determining rank value, and changes the parent node; a scheduling message transmission module for delivering a join request message to a root node, and transmitting a deallocation request message; a scheduling message receiving module for receiving the join request message, and receiving the deallocation message, and slot information; a scheduling message processing module for performing a join request message process, a deallocation request message process, and a slot information process; a DIO message processing module for receiving a DIO message and updating neighbor node information; a scheduling manager module for performing scheduling message reception, a scheduling algorithm process, and slot information transmission; and a slot management module for performing scheduling table management, active slot addition, and active slot deletion.

Description

Apparatus and Method for Scheduling in TCS and RPL-based Industrial Internet Networks

The present invention relates to a TSCH and RPL-based industrial IoT network, and more particularly, to an apparatus and method for scheduling in a TSCH and RPL-based industrial IoT network with low latency and high network efficiency. .

IEEE 802.15.4e is a standard that improves the MAC layer for the industrial wireless sensor network environment.

TSCH (Time Slotted Channel Hopping) is one of the IEEE 802.15.4e modes and shows high reliability and low power operation. All nodes on the IEEE 802.15.4e network are synchronized.

In the TSCH, time is divided into slots, and a slot frame is configured by a bundle of time slots.

Every node continuously repeats the scheduled slot frame and performs one of the following operations: transmit, receive, and sleep in a time slot.

TSCH reduces problems such as external interference and multi-path fading through channel hopping.

The schedule is represented by a two-dimensional array of (slotOffset, channelOffset), and the elements of the array are called "cells".

When a cell is scheduled to be trnasmit or receive, the cell can communicate with neighboring nodes in the cell. The IEE 802.15.4e standard does not define a scheduling scheme.

A well known scheduling method is DeTAS (Decentralized Traffic Aware Scheduling).

DeTAS is scheduling that minimizes the active slot length.

Each node sends its traffic information to the parent. When the traffic information is received, it updates its traffic information and sends it back to the parent. In this way, each node carries traffic information to the route.

The root node divides the child nodes into even schedules or odd schedules.

Even scheduled nodes transmit on even slotOffsets and receive on odd slotOffsets. Odd-scheduled nodes behave the opposite of evem-scheduled nodes.

The feature of DeTAS divides even and odd schedules, minimizing active slot length, and alternating transmit and receive slots, so that buffer overflow does not occur, and only one node is assigned to one slot for interference. It is characteristic that it does not occur.

However, DeTAS is a new node to join or. If the parent node changes, the root node needs to re-determine even and odd schedules of the child nodes, and all nodes need to be rescheduled because there is no slot space for the new node.

Therefore, any change in the routing graph increases the overhead required for scheduling.

In other words, such a prior art does not consider the number of control packets necessary for scheduling, and when the routing graph changes, the entire scheduling needs to be rescheduled, thereby increasing the number of control packets and increasing the overhead. have.

Therefore, there is a need for development of a technology for scheduling in a new TSCH and RPL-based industrial IoT network, which has improved network efficiency with low overhead scheduling.

The present invention is to solve the problem of scheduling in the TSCH and RPL-based industrial IoT network of the prior art, TSCH and RPL-based industrial IoT network with reduced latency and high network efficiency with low overhead scheduling It is an object of the present invention to provide an apparatus and method for scheduling in.

The present invention provides an apparatus and method for scheduling in a TSCH and RPL-based industrial IoT network to allocate the minimum slot that can meet the traffic required in the industrial IoT network, and to minimize the overhead required for scheduling Its purpose is.

In the RPL routing protocol forming a tree-like path, the present invention implements centralized scheduling that provides an appropriate slot with minimal overhead to satisfy the traffic of a node participating in a root node when a new node joins a network. An object of the present invention is to provide an apparatus and method for scheduling in an industrial IoT network based on TSCH and RPL.

According to the present invention, scheduling is performed in a TSCH and RPL-based industrial IoT network that reduces overhead by minimizing the number of overcontrol packets because the number of slots is not allocated or rescheduled, and only a few nodes are allocated or removed. It is an object of the present invention to provide an apparatus and method for the same.

The objects of the present invention are not limited to the above-mentioned objects, and other objects that are not mentioned will be clearly understood by those skilled in the art from the following description.

In order to achieve the above object, an apparatus for scheduling in an industrial IoT network based on TSCH and RPL according to the present invention selects a parent node by determining network participation, determines a link value, and selects a parent to change the parent node. Management module; Scheduling message transmission module for forwarding a Join Request message to the root node and sending a Deallocation Request message; Receives a Join Request message and Deallocation Request Scheduling message receiving module for receiving a message, slot information; Scheduling message processing module for performing a join request message processing, Deallocation Request message processing, slot information processing; Receives DIO message, neighbor node DIO message processing module for updating information; scheduling message reception, scheduling algorithm processing The scheduling manager module for performing a transmission slot information; scheduling table management, an active slot added, slot management module for performing an active slot deleted; characterized in that it comprises a.

Here, the parent selection management module includes a network participation determining unit determining network participation, a link value determining unit determining a link value, a parent node selecting unit selecting a parent node, and a parent node changing performing a parent node change. The scheduling message transmission module includes a connection request message transmission unit for transmitting a join request message to a root node, and a reassignment request message transmission unit for transmitting a relocation request message. The scheduling message receiving module may include: a connection request message receiving unit receiving a join request message, a relocation request message receiving unit reassigning request message, and a slot information receiving unit receiving slot information; And the scheduling message processing module is configured to process a join request message. And a connection request message processing unit, a reassignment request message processing unit processing a relocation request message, and a slot information processing unit processing slot information.

The DIO message processing module includes a DIO message receiving unit for receiving a DIO message, a neighbor node information updating unit for updating neighbor node information, and the scheduling manager module performs a scheduling message receiving unit for receiving a scheduling message, and scheduling algorithm processing. And a slot information transmitter for performing slot information transmission. The slot management module includes a scheduling table manager for managing a scheduling table, an active slot adder for performing active slot addition, and an active slot deletion. It characterized in that it comprises an active slot deletion unit to perform.

The slot management module may add or delete slots only for nodes related to a path without rescheduling the entire scheduling when a new node joins or a parent node is changed.

A method for scheduling in a TSCH and RPL-based industrial IoT network according to the present invention for achieving another object includes a node u when a new node joins the network in scheduling in a TSCH and RPL-based industrial IoT network. Selecting a parent node by connecting to a network; putting link information for slot assignment in a link queue; transmitting a connection request message to a parent node; and, in the case of a node whose parent node has changed, Receiving a DIO message from the neighbor node V and updating the neighbor information; determining whether the rank value of the current parent node is higher than the neighbor node v and changing the parent node; a cell list storing cells to be deleted Inserting its own tx cell into the old parent node and sending a deallocation request message to the old parent node; assigning a slot for the new parent node To insert the link information of the new parent node in the link queue sending to the new parent node; it characterized in that it comprises a.

Here, when a new node joins a network, a newly joined node u puts link information into a link queue and transmits it to a parent node. When a connection request message is received from a child node, the node receiving the message is not a root node. It handles the connection request message by distinguishing between the root node and the root node.If it is not the root node, it adds its own and parent's link information to the link queue and sends it to the parent node in the link request message. In this case, the scheduling request is made to the scheduling manager.

When a new node joins the network, when an EB (Enhanced Beacon) is received from a neighboring node, synchronization is performed, and when the new node joins the network, the newly joined node requests a connection request message to the parent node for scheduling to receive an additional slot. Join Request), the connection request message is delivered to the root node, the root node requests the scheduling to the scheduling manager, the scheduling manager allocates a slot and delivers it to the node, characterized in that the scheduling proceeds.

When the parent node is changed, if a neighbor node having a value smaller than the rank value of the parent node is created, the node changes the parent node to a neighbor node having a smaller rank and then changes the parent node. In addition, the slot is additionally allocated according to the changed routing, and the existing slot is removed.

When the node receiving the scheduling message receives the connection request message from the child node, the node determines its rank value and, if its rank is greater than 0, puts the link information in the link queue for additional slot allocation. The connection request message is transmitted to the parent node, and if its rank is less than or equal to 0, the connection request message is transmitted to the scheduling manager.

In case of receiving a deallocation message from a child node, if its rank value is determined and its rank is greater than 0, it starts deallocation processing and repeats until the cell list is empty. If there is an rx cell that satisfies the condition and removes the cell, delete the cell and delete the tx cell that is larger than the deleted rx cell from the list of tx cells and send it to the parent node when all deletions are completed. In this case, the transaction manager requests a deallocation request from the scheduling manager.

The apparatus and method for scheduling in an industrial IoT network based on TSCH and RPL according to the present invention have the following effects.

First, it reduces latency in scheduling in industrial IoT networks based on TSCH and RPL, and improves network efficiency with low overhead scheduling.

Second, it can allocate the minimum slots to meet the traffic demands of industrial IoT networks and reduce the overhead required for scheduling.

Third, in the RPL routing protocol forming a tree path, when a new node joins the network, centralized scheduling can be implemented that provides an appropriate slot with minimum overhead to satisfy the traffic of the node participating in the root node. have.

Fourth, even if the routing graph changes, rescheduling is not performed, and only a few related nodes allocate or remove slots, thereby reducing overhead by minimizing the number of overcontrol packets.

1 is a routing graph and scheduling table when a new node joins a network

2 is a timing diagram when a new node joins a network

3 is a routing graph and scheduling table when a parent node is changed

4 is a timing diagram when a parent node is changed

5 is a block diagram of an apparatus for scheduling in an industrial IoT network based on TSCH and RPL according to the present invention

6 is a flowchart of a node newly joining a network or a parent node is changed.

7 is a flowchart of a node receiving a scheduling related message.

8A and 8B are flowcharts illustrating a scheduling algorithm of a scheduling manager.

Hereinafter, a preferred embodiment of an apparatus and method for scheduling in an industrial IoT network based on TSCH and RPL according to the present invention will be described in detail.

Features and advantages of the apparatus and method for scheduling in the TSCH and RPL-based industrial IoT network according to the present invention will become apparent from the detailed description of each embodiment below.

1 is a routing graph and scheduling table when a new node joins a network, and FIG. 2 is a timing diagram when a new node joins a network.

3 is a routing graph and a scheduling table when the parent node is changed, and FIG. 4 is a timing diagram when the parent node is changed.

In the RPL routing protocol forming a tree-like path, the present invention implements centralized scheduling that provides an appropriate slot with minimal overhead to satisfy the traffic of a node participating in a root node when a new node joins a network. It is.

The apparatus and method for scheduling in a TSCH and RPL-based industrial IoT network according to the present invention do not reschedule even if a change is made to the routing graph, and because only a few nodes are allocated or removed slots, the number of overcontrol packets Reduce the overhead to a minimum.

An apparatus and method for scheduling in a TSCH and RPL based industrial IoT network according to the present invention have the following rules.

First, a packet generated by each node within a slot frame includes a rule that must arrive to the root, and a node close to the root node needs an additional slot because the packet received from the child nodes must be forwarded.

Second, to ensure high reliability and low latency of the network, scheduling is performed so as not to generate interference.

Third, in order to minimize the overhead required for scheduling, when a new node joins or a parent node is changed, only nodes related to a path are added or deleted without rescheduling the entire scheduling.

The configuration of an apparatus for scheduling in an industrial IoT network based on TSCH and RPL according to the present invention is as follows.

As shown in FIG. 5, a parent selection management module 10 which determines a network participation, determines a link value, selects a parent node, performs a parent node change, transmits a Join Request message to a root node, and a Deallocation Request message The scheduling message transmission module 20 for transmitting the message, the scheduling message receiving module 30 for receiving the Join Request message and receiving the Deallocation Request message and the slot information, and the Join Request message processing, the Deallocation Request message processing, and the slot information processing. A scheduling message processing module 40 to perform, a DIO message processing module 50 to receive a DIO message and update neighbor node information, and a scheduling manager module to perform scheduling message reception, scheduling algorithm processing, and slot information transmission ( 60) and slot management that performs scheduling table management, active slot addition, and active slot deletion. It comprises a module 70.

Here, the parent selection management module 10 includes a network participation determining unit 10a for determining network participation, a link value determining unit 10b for determining a link value, and a parent node selecting unit 10c for selecting a parent node. And a parent node change unit 10d for performing a parent node change.

The scheduling message transmission module 20 may further include a connection request message transmitter 20a for transmitting a join request message to a root node, and a reassignment request message transmitter for transmitting a relocation request message. (20b).

The scheduling message receiving module 30 includes a connection request message receiving unit 30a that receives a connection request message, a relocation request message receiving unit 30b that receives a reassignment request message, and a slot. It includes a slot information receiver 30c for receiving information.

The scheduling message processing module 40 includes a connection request message processing unit 40a for processing a connection request message, a reassignment request message processing unit 40b for processing a deallocation request message, and a slot. A slot information processing unit 40c for processing information is included.

The DIO message processing module 50 includes a DIO message receiver 50a for receiving a DIO message and a neighbor node information updater 50b for updating neighbor node information.

The scheduling manager module 60 includes a scheduling message receiver 60a for receiving a scheduling message, a scheduling algorithm processor 60b for scheduling algorithm processing, and a slot information transmitter 60c for slot information transmission.

The slot management module 70 includes a scheduling table manager 70a that manages the scheduling table, an active slot adder 70b that performs active slot addition, and an active slot deleter 70c that performs active slot deletion. Include.

Such an apparatus for scheduling in an industrial IoT network based on TSCH and RPL according to the present invention is (situation 1) when a new node joins the network, and (situation 2) when a parent node is changed as follows. It works.

(Situation 1) When a new node joins the network

When an EB (Enhanced Beacon) is received from a neighbor node, synchronization is performed and the network is joined.

The newly participating node sends a join request message to the parent node for scheduling to allocate additional slots.

The connection request message is delivered to the root node, which requests scheduling to the scheduling manager.

The scheduling manager allocates an appropriate slot and then delivers it to the node.

1 illustrates a routing graph and a scheduling table when a new node joins a network.

2 shows a timing diagram when node n ₃ participates in a network.

Node n ₃ sends a Join Request message to a parent node n ₁ , and n ₁ forwards a Join Request message to a root node n ₀ .

n ₀ delivers a message to the scheduling manager to schedule the scheduling manager, and each node receives slot allocation information from the manager.

Join Request message is sent including linkQueue.

linkQueue is a queue that stores link information consisting of (u, Parent (u), DODAGrank (u), and Trans (u)). u denotes a local node included in the network, and Parent (u) denotes the parent node of node u.

DODAGrank (u) means the DODAGrank value of node u, and Trans (u) means the number of slots required for node u to transmit in the slotframe.

6 is a flowchart of a node newly joining a network or a parent node is changed.

7 is a flowchart of a node receiving a scheduling related message, and FIG. 8 is a flowchart illustrating a scheduling algorithm of a scheduling manager.

6 shows a flowchart of a node newly participating in a network or a node whose parent node is changed. A node u newly joined in the network transmits link information to a parent node by putting link information in a link queue.

When a join request is received from a child node, if the node receiving the message is not the root node or the root node, the join request message is processed differently.

First, if it is not a root node, it adds link information of itself and its parent to the linkQueue and transmits it to the parent node in a Join Request message.

In the case of the root node, a scheduling request is made to the scheduling manager.

Specifically, the operation in a node that newly joins the network or whose parent node is changed is performed as follows.

As shown in FIG. 6, [when newly joining the network], node u joins the network (S610) → selects a parent node (S611) → inserts link information for slot allocation in the link queue (S612) → connects to the parent. The request message proceeds in the order of transmission (S613).

And [in the case of a node whose parent node is changed] receives a DIO message to the neighbor node V (S601) → update the neighbor information (S602) → determine whether the rank value of the current parent is higher than the neighbor node v (S603) → the parent Change (S605) → Put its tx cell in the cellList that stores the cells to be deleted (S606) → Send the release request message to the previous parent node (S607) → Since the slot allocation for the new parent is needed, The link information is added to the link queue (S612) and then transmitted to the new parent (S613).

7 is a flowchart illustrating a node receiving a scheduling related message.

When the scheduling manager receives the JoinRequest, scheduling begins.

Scheduling will continue until linkQueue runs out.

First, get the link from the linkQueue.

If the link's DODAGrank is less than 1, ts (time slot offset) is 0. If the DODAGrank is greater than 1, ts is added to the last allocated tx slot in the parent node scheduling information of the link. Put it in.

ch (channel offset) is set to DODAGrank of the link minus 1.

If a slot with the corresponding (ts, ch) is not assigned and no interference occurs, the link is assigned to the slot.

If slots have already been allocated or cause interference, the ts value is incremented by 1 and repeated until assigned.

If allocated, decrement the trans value of the link by one, and if the trans value is greater than zero, requeue it so that an additional slot can be allocated.

When linkQueue is gone, the allocated slot information is sent to the nodes, and scheduling is finished.

Specifically, the processing sequence at the node receiving the scheduling related message is as shown in FIG. 7, when [the connection request message message is received from the child (S720)], its own rank is greater than zero by determining its rank value. If (S721) → put link information for additional slot allocation in the link queue (S723) → sends a connection request message to its parent (S724), if its rank is less than or equal to 0 (S721) → scheduling The connection request message is sent to the manager in the order of S722.

In case [deallocation message is received from a child (S701)], if its rank is greater than 0 by determining its rank value (S702) → start deallocation processing (S704) → repeat until cellList becomes empty → cellList → Remove the cells from the rx cell that satisfies the condition. → Delete tx cells larger than the deleted rx cells in the tx cell list (S705 ~ S714) → When all deletions are completed, send them to the parent node (S709). Proceed.

And if his rank is less than or equal to 0 (S702) → makes a deallocation request (S703) to the scheduling manager.

In case of receiving a reponse message from the scheduling manager (S730), the slot information is inserted into the scheduling table (S731) → the slot is activated (S732).

Scheduling of the scheduling manager, as shown in Figure 8a, [in the case of receiving a connection request message (S801) (S802) proceeds until the linkQueue is empty (S803) → remove the link from the linkQueue (S806) → the DODAGrank value of the link If this value is greater than 1, ts is calculated using the startTs function (last Ts of the parent node) (S808) → If the link's DODAGrank value is less than or equal to 1, ts becomes 0 (S809) → ch is 1 from the link's DODAGrank value. Subtracted value (S810) → The slot is available in the schedule table, and if there is no conflict, put it in the scheduling table (S811) → Repeat until the Trans value of the link becomes 0 (S813 ~ S816) → Corresponds to the schedule table If a slot is available and a collision occurs, while the value of ts is increased by 1 and repetition (S812)-> linkQueue becomes empty, scheduling is completed (S804), and the procedure is transmitted to the child node (S805).

When receiving a deallocation message (S820) (S821), as shown in FIG. 8B, iterates until the cellList becomes empty → removes the cell from the cellList → if there is an rx cell that satisfies the condition, it is deleted (S822 to S827). Proceed in order.

(Situation 2) When the parent node changes

When the RPL DIO message is received from the neighbor node, the neighbor information is updated.

If a neighbor node has a value smaller than the rank value of the parent node, the node changes the parent node to a neighbor node having a rank of a smaller value.

If you change the parent node, you need to allocate additional slots and remove existing slots to accommodate the changed routing.

3 illustrates a routing graph and scheduling when a parent node is changed.

4 shows a timing diagram in the situation of FIG. 3.

When node n _{3 changes} its parent from node n ₁ to node n ₀ , it sends a relocation request message to node n ₁ , the former parent, to remove the existing assigned slot. n ₀ is sent a Join Request message to allocate a new slot.

The reassignment request message is sent to the scheduling manager.

Because deallocation processing is done locally, the scheduling manager does not send a response message.

The connection request message is processed in the same way as described in (Scenario 1).

Deallocation Request message is sent including cellList.

cellList is a list of cells consisting of (ts, ch, txrx, neighbor).

6 shows a process in which a node whose parent has been changed through a DIO message transmits a Deallocation Request message to a previous parent node by inserting its tx cells in a cellList and transmits a Join Request to a new parent.

7 shows a process of processing when a Deallocation Request message is received.

If it is not the root node, deallocation processing proceeds as long as cellList.

After retrieving a cell from the cellList, if the cell is related to itself, the corresponding slot is removed from the assigned slot.

And among the tx cells of its own, deallocate the smallest cell among the cells larger than the slot offset value of the corresponding cell.

When deallocation processing is completed, the removed tx cells are added to the cellList and a Deallocation Request message is transmitted to the parent node.

If you are the root, send to the scheduling manager to update the scheduling table.

Such an apparatus and method for scheduling in a TSCH and RPL-based industrial IoT network according to the present invention allocates a minimum slot capable of meeting traffic required in an industrial IoT network and minimizes the overhead required for scheduling. It is to reduce.

It will be understood that the present invention is implemented in a modified form without departing from the essential features of the present invention as described above.

Therefore, the described embodiments should be considered in descriptive sense only and not for purposes of limitation, and the scope of the present invention is shown in the claims rather than the foregoing description, and all differences within the equivalent scope are included in the present invention. It should be interpreted.

The present invention as described above is an apparatus for scheduling in the industrial IoT network based on TSCH and RPL to allocate the minimum slot that can meet the traffic required in the industrial IoT network, and to minimize the overhead required for scheduling And to a method.

Claims

A parent selection management module for determining a network participation, determining a link value, selecting a parent node, and performing a parent node change;

A scheduling message transmission module for delivering a Join Request message to the root node and transmitting a Deallocation Request message;

A scheduling message receiving module for receiving a Join Request message, a Deallocation Request message, and slot information;

A scheduling message processing module for processing a join request message, a deallocation request message, and slot information processing;

A DIO message processing module for receiving a DIO message and updating neighbor node information;

A scheduling manager module for receiving a scheduling message, processing a scheduling algorithm, and transmitting slot information;

Slot management module for performing scheduling table management, active slot addition, active slot deletion; apparatus for scheduling in the TSCH and RPL-based industrial IoT network.
The method of claim 1, wherein the parent selection management module performs a network participation determining unit determining network participation, a link value determining unit determining a link value, a parent node selecting unit selecting a parent node, and changing a parent node. Includes the parent node change unit

The scheduling message transmission module includes a connection request message transmission unit for transmitting a connection request message to a root node, a reassignment request message transmission unit for transmitting a relocation request message,

The scheduling message receiving module includes a connection request message receiving unit receiving a join request message, a relocation request message receiving unit receiving a reassignment request message, and a slot information receiving unit receiving slot information. and,

The scheduling message processing module includes a connection request message processing unit processing a join request message, a reassignment request message processing unit processing a relocation request message, and a slot information processing unit processing slot information. Apparatus for scheduling in TSCH and RPL-based industrial IoT network, characterized in that.
The DIO message processing module of claim 1, wherein the DIO message processing module comprises a DIO message receiver for receiving a DIO message, and a neighbor node information updater for updating neighbor node information.

The scheduling manager module includes a scheduling message receiver for receiving a scheduling message, a scheduling algorithm processor for processing a scheduling algorithm, and a slot information transmitter for transmitting slot information.

The slot management module includes a scheduling table manager that manages a scheduling table, an active slot adder that performs active slot addition, and an active slot deleter that performs active slot deletion, wherein the industrial IoT based on TSCH and RPL Device for scheduling in a network.
The method of claim 1, wherein the slot management module,

Apparatus for scheduling in TSCH and RPL-based industrial IoT networks, characterized in that when the new node joins or the parent node is changed, only slots related nodes are added or deleted without rescheduling the entire scheduling.
In scheduling in an industrial IoT network based on TSCH and RPL,

If a new node joins the network,

Node u connecting to the network to select a parent node;

Putting link information for slot allocation in a link queue;

Transmitting a connection request message to a parent node;

For nodes whose parent node has changed,

Receiving a DIO message from a neighbor node V and updating neighbor information;

Changing a parent node by determining whether a rank value of a current parent node is higher than a neighbor node v;

Inserting its tx cell into a cell list (cellList) storing cells to be deleted and sending an unassignment request message to a previous parent node;

Inserting link information with a new parent node in a link queue for slot allocation for a new parent node and transmitting the link information to a new parent node; a method for scheduling in an industrial IoT network based on TSCH and RPL .
The method of claim 5, wherein when a new node joins the network,

Newly joined node u puts the link information in the link queue and transmits it to the parent node.

When a connection request message is received from a child node, the connection request message is processed by distinguishing between the case where the node receiving the message is not the root node and the root node.

In the case of non-root node, the link information of self and parent is added to link queue, added to link request message, transmitted to parent node, and in case of root node, TSCH is requested by scheduling manager. And a method for scheduling in an RPL based industrial IoT network.
The method of claim 5, wherein when a new node joins the network,

When you receive an Enhanced Beacon (EB) from a neighbor node, synchronization occurs, join the network,

The newly participating node sends a join request message to the parent node for scheduling to allocate additional slots, the connection request message is sent to the root node, the root node requests scheduling to the scheduling manager, and the scheduling manager slot Scheduling is carried out in a manner that is delivered to the node after allocating the TSCH and RPL-based scheduling in the industrial IoT network.
The method of claim 5, wherein when the parent node is changed,

When a neighbor node having a value smaller than the parent node's rank value is generated, the node changes the parent node to a neighbor node having a smaller rank value.

The method for scheduling in TSCH and RPL-based industrial IoT networks, characterized in that when the parent node is changed, additional slots are allocated according to the changed routing, and existing slots are removed.
The method of claim 5, wherein the node receiving the scheduling related message receives the connection request message from the child node.

If it is determined that its rank value is greater than 0, it puts link information for additional slot allocation in the link queue, and sends a connection request message to its parent node.

And transmitting a connection request message to a scheduling manager when its rank is less than or equal to zero.
The method of claim 5, wherein when a deallocation message is received from a child node,

If it is determined that its rank value is greater than zero, it starts deallocation processing and iterates until the cell list is empty, and repeatedly extracts the cell from the cell list and satisfies the condition. If there is a cell, delete it and delete the tx cell larger than the deleted rx cell in the tx cell list, and when all deletions are completed, send it to the parent node.

A method for scheduling in an industrial IoT network based on TSCH and RPL, characterized in that when the rank is less than or equal to 0, a deallocation request is made to the scheduling manager.