KR20180071183A - Transmission method and apparatus using shared timeslot and broadcast, and firmware update method and apparatus using the same - Google Patents

Abstract

Provided are a method for transmitting a packet and a network management apparatus to efficiently transmit data. The method comprises the steps of: broadcasting a plurality of packets using a plurality of shared time slots shared by a plurality of network nodes and a basic channel for downlink communication; confirming at least one non-received packet not received by the plurality of network nodes of the plurality of packets; determining a distributor for transmitting at least one non-received packet and a distribution timeslot and a distribution channel for transmitting at least one non-received packet; and broadcasting transmission schedule information including the distributor, information on the distribution timeslot, and information on the distribution channel using the basic channel.

Description

TECHNICAL FIELD [0001] The present invention relates to a transmission method and apparatus using a shared time slot and a broadcast, and a firmware updating method and apparatus using the same.

The present invention relates to a transmission method and apparatus using shared timeslots and broadcasts.

Currently, a personal area network (PAN) coordinator (PAN) in a wireless personal area network (WPAN) assigns an uplink (UL) and a downlink (DL) according to a WPAN join request of network nodes Management.

The network node is allocated uplink and downlink.

On the other hand, due to the characteristics of the network, when uplink communication occurs more frequently than downlink communication and downlink communication is temporarily required, downlink usability is degraded.

There is a need for a data transmission method that improves downlink efficiency by temporarily using a small number of downlinks in such networks. There is also a need for a data transfer method that improves the efficiency of firmware (F / W) firmware updates for network nodes in such networks.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and apparatus for efficiently transmitting data using broadcast and shared timeslots in a network.

Another object of the present invention is to provide a method and an apparatus for efficiently updating firmware using such a data transfer method.

According to one embodiment, a packet transmission method of a network management apparatus is provided. The packet transmission method comprising: broadcasting a plurality of packets using a plurality of shared time slots and a base channel shared by a plurality of network nodes for downlink communication; Identifying one or more unreceived packets not received by a plurality of network nodes among the plurality of packets; Determining a distribution time slot and a distribution channel for transmission of one or more unreceived packets and a distribution of one or more unreceived packets; And broadcasting the transmission schedule information including the distributor, information on the distribution time slot, and information on the distribution channel using the base channel.

The step of checking one or more unreceived packets in the packet transmission method may include checking the number of unreceived nodes that failed to receive one or more unreceived packets among a plurality of network nodes by one or more unreceived packets.

Wherein the step of determining in the packet transfer method calculates the maximum number of packets allocated to the distribution channel using the number of one or more unreachable packets, the number of channels for one downlink timeslot, and the number of shared time slots. ; And determining a packet to be allocated to the distribution channel of at least one of the unreceived packets, based on the number of unreceived nodes and the maximum number of packets.

Wherein determining in the packet transmission method comprises: determining a first timeslot of the plurality of shared timeslots as a distribution timeslot; And determining a packet to be allocated to a distribution channel for a first timeslot such that receivers of packets assigned to a first timeslot of one or more unreceived packets are not duplicated.

Wherein the distribution channel for the distribution time slot in the packet transmission method comprises a base channel and a first channel, and wherein the step of determining, when a first one of the one or more missing packets is assigned to a base channel, Determining a first node that has received the first packet as a distributor to transmit a second one of the one or more missing packets on a first channel.

The packet transmission method includes a step of transmitting information on a plurality of shared time slots, information on a basic channel, a number of a plurality of packets, and a transmission order of a plurality of packets before a plurality of packets are broadcast, And broadcasting through a base channel in a time slot belonging to the interval.

Wherein the step of identifying one or more missing packets in the packet transmission method comprises: receiving, from each of the plurality of network nodes, an unreceived packet bitmap representing one or more unreceived packets of each of the plurality of network nodes; And receiving, from each of the plurality of network nodes, information indicating the strength of the wireless signal and the quality of the wireless signal of the peripheral nodes of the plurality of network nodes.

Wherein the distribution channel for the first time slot in the packet transmission method includes a base channel and a first channel, and the step of determining includes determining whether a first packet having the largest number of non- Scheduling such that packets are not transmitted on a first channel for a first timeslot if assigned to a base channel for one timeslot.

In the packet transmission method, the transmission schedule information may further include a maximum number of packets and a transmission order of one or more unreceived packets.

In the packet transmission method, when a distribution channel is a basic channel, a packet allocated to a basic channel among at least one unreceived packet is transmitted by the network management apparatus, and when the distribution channel is a first channel different from the basic channel, A packet allocated to the first channel among the non-received packets may be transmitted by at least one of the plurality of network nodes.

According to another embodiment, a network management apparatus for managing a plurality of network nodes is provided. The network management apparatus comprising: a communication unit for broadcasting a plurality of packets using a plurality of shared time slots and a basic channel shared by a plurality of network nodes for downlink communication; And determining a distribution timeslot and distribution channel for transmission of a distributor and one or more unreceived packets to send one or more unreceived packets and identifying one or more unreceived packets not received by a plurality of network nodes of the plurality of packets, Information on the distribution time slot, and transmission schedule information including information on the distribution channel, and the communication unit may broadcast the transmission schedule information using the base channel.

In the network management apparatus, the processor can identify the number of unreceived nodes that have failed to receive one or more unreceived packets among the plurality of network nodes, by one or more unreceived packets.

Wherein the processor in the network management apparatus calculates a maximum number of packets allocated to the distribution channel using the number of one or more unreachable packets, the number of channels for one downlink time slot, and the number of shared time slots, A packet to be allocated to a distribution channel among at least one unreceived packet based on the number of nodes and the maximum number of packets.

Wherein the processor of the network management apparatus determines a first time slot of the plurality of shared time slots as a distribution time slot so that the receivers of the packets allocated to the first time slot of the at least one non- Lt; RTI ID = 0.0 > a < / RTI > distribution channel for a slot.

Wherein the distribution channel for the first time slot of the distribution time slot in the network management apparatus includes a base channel and a first channel and the processor is configured such that a first one of the one or more unreceived packets is allocated to a base channel of the first time slot The first node having the first packet of the plurality of network nodes may be determined as a distributor to perform packet transmission using the first channel of the first timeslot.

Wherein the distribution channel for the first time slot of the distribution time slot in the network management apparatus includes a base channel and a first channel and the processor is configured to determine whether a first packet having the largest number of non- May be scheduled to not be transmitted on the first channel of the first timeslot if assigned to the base channel of the slot.

In the network management apparatus, before broadcasting a plurality of packets, the communication unit may transmit information on a plurality of shared time slots, information on a basic channel, a number of a plurality of packets, and a transmission order of a plurality of packets, period through a basic channel in a time slot belonging to a period.

In the network management apparatus, a plurality of network nodes are a plurality of sensors existing in a sensor network, and a plurality of packets may be included in firmware data for updating firmware of a plurality of network nodes.

According to yet another embodiment, a method is provided for the PAN coordinator to update firmware for a plurality of sensors. The firmware updating method includes: broadcasting a plurality of packets for updating firmware of a plurality of sensors using a plurality of shared time slots and a basic channel shared by a plurality of sensors; Identifying one or more unreceived packets not received by the plurality of sensors among the plurality of packets; And scheduling a distribution time slot and distribution channel for transmission of one or more unreceived packets, wherein if the distribution channel is a first channel different from the base channel, A packet assigned to the first channel is transmitted by at least one of the plurality of sensors.

The firmware update method includes a step of transmitting information on a plurality of shared time slots, information on a basic channel, a number of a plurality of packets, and a transmission order of a plurality of packets before a plurality of packets are broadcast, And broadcasting through a base channel in a time slot belonging to the interval.

According to an embodiment of the present invention, a method and apparatus for efficiently transmitting data using broadcast and shared timeslots in a network can be provided.

Also, according to the embodiment of the present invention, a data transmission method may be provided that mixes broadcasting by a network management apparatus and direct data transmission between network nodes. In this way, efficient downlink data transmission can be provided.

According to an embodiment of the present invention, a method and apparatus for efficiently updating firmware of a plurality of network nodes can be provided.

1 is a diagram illustrating a method of assigning uplink and downlink to a network node;
2 is a diagram illustrating a network management method according to an embodiment of the present invention.
3 is a diagram illustrating a network management method according to another embodiment of the present invention.
4 is a diagram illustrating a star network including one PANC and a plurality of network nodes.
5 is a diagram showing a beacon frame.
FIG. 6 is a diagram showing a detailed octet of the 'down GTS specification' field.
7 is a diagram illustrating a shared downlink GTS (guaranteed time slot).
8 is a diagram illustrating a data transmission method according to an embodiment of the present invention.
9 is a diagram illustrating a method by which a network management apparatus generates a data transmission schedule according to an embodiment of the present invention.
10 is a diagram illustrating a network management apparatus according to an embodiment of the present invention.
11 is a diagram of a computing device, in accordance with an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

In the present specification, duplicate descriptions are omitted for the same constituent elements.

Also, in this specification, when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, May be present. On the other hand, in the present specification, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that no other element exists in between.

Furthermore, terms used herein are used only to describe specific embodiments and are not intended to be limiting of the present invention.

Also, in this specification, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

Also, in this specification, the terms " comprise ", or " have ", and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, parts, or combinations thereof.

Also, in this specification, the term 'and / or' includes any combination of the listed items or any of the plurality of listed items. In this specification, 'A or B' may include 'A', 'B', or 'both A and B'.

Hereinafter, a method for efficiently transmitting data using broadcast and shared time slots in a network and a method for efficiently updating firmware using the same will be described.

1 is a diagram illustrating a method of assigning uplink and downlink to a network node;

Specifically, FIG. 1 illustrates a case where beacons are transmitted for each of four super frames. 1 denotes the identifier of the superframe and BI = 0, BI = 1, ... denotes the identifier of the beacon, and GTS = 0, GTS = 1 , ... denotes an identifier of a guaranteed time slot (GTS). For example, a beacon (BI = 0) exists in the first superframe (SF = 0) among the four superframes (SF = 0, SF = 1, ..., SF = 3) (BI = 1) exists in the first super frame (SF = 0) among the SFs (SF = 0, SF = 1, ..., SF =

A superframe with SF = 0 may include a beacon, a contention access period (CAP), and a contention-free period (CFP). One superframe may include 16 time slots. A CFP belonging to a superframe SF = 0 may include seven GTSs (GTS = 0, GTS = 1, ..., GTS = 6) = 3) may include 16 GTSs (GTS = 0, GTS = 1, ..., GTS = 15). Beacons can be transmitted in the first time slot included in the superframe.

In the WPAN, the PANC allocates and manages the uplink and downlink according to the WPAN join request of the network node.

The WPAN join request of the network node and the WPAN join approval thereof are made in the CAP section.

The network node may be assigned at least one GTS in the CFP interval as a dedicated uplink and downlink for the network node in the WPAN join request. At this time, the network nodes are allocated uplink and downlink, and configure the network.

Specifically, in the WPAN, the PANC can allocate a plurality of GTSs for uplink and downlink as dedicated uplink and downlink for the network node according to the WPAN join request of the network nodes. As a result, the efficiency of the network is deteriorated.

In a network environment in which either uplink communication or downlink communication occurs mainly, it is inefficient that both the uplink and the downlink are allocated to the network node. For example, due to the nature of the network, if uplink communication occurs more frequently than downlink communication and downlink communication is temporarily needed, the downlink utilization is degraded.

In order to solve this problem, if the communication mainly occurs in the uplink, only the uplink can be allocated to the network node, and the downlink can be shared and allocated to the network node to be used according to the needs of the network node.

Especially, in a wireless network, when the network management apparatus effectively transmits (for example, 1: N transmission) a common packet to a plurality of network nodes, uplink and downlink control are required.

Hereinafter, a network management method and apparatus for solving the problem of low WPAN network efficiency will be described. Further, a data transmission method and apparatus for improving downlink efficiency by temporarily using a small number of downlinks will be described. In addition, a data transmission method and apparatus for improving the efficiency of firmware update for network nodes will be described.

The network management apparatus can transmit / receive data to / from one or more network nodes subscribed to the network using time slots. In particular, the network management device may broadcast one or more data units to network nodes subscribed to the network. The network management apparatus may receive unreceived data information from the network nodes indicating data units not received by the network nodes among the broadcasted one or more data units. The network management apparatus may then retransmit one or more data units to the one or more network nodes based on the missing data information.

2 is a diagram illustrating a network management method according to an embodiment of the present invention.

The network coordinator (hereinafter, 'coordinator') generates time slot identification information indicating a time slot allocated for the downlink of the target network node (s) (S110).

The timeslot allocated for the downlink of the target network node (hereinafter referred to as the 'target node') may be a time slot whose allocation is guaranteed for the target node. The timeslot allocated for the downlink of the target node may be determined among the shared timeslots. Accordingly, the timeslot allocated for the downlink of the target node may be a shared timeslot.

The time slot identification information generated in step S110 may include at least one of a beacon ID (identifier) and a superframe ID and a slot ID (slot ID).

Next, the coordinator transmits time slot identification information to the target node (s) (S120).

3 is a diagram illustrating a network management method according to another embodiment of the present invention. Description of the same parts as the network management method illustrated in FIG. 2 in the network management method illustrated in FIG. 3 will be omitted.

First, the coordinator determines whether to assign the downlink to the target node (s) (S210).

Next, the coordinator generates time slot identification information indicating a time slot allocated for the downlink of the target node (s) (S220).

Next, the coordinator generates target node identification information indicating the target node (s) (S230). The coordinator can use the target node identifier (ID) display method used in the network for the target node identification information.

Next, the coordinator transmits time slot identification information and target node identification information to the target node (s) (S240). Specifically, the coordinator may transmit the time slot identification information and the target node identification information to the target node (s) using one time slot. Alternatively, the coordinator may transmit time slot identification information and target node identification information to the target node (s) using different time slots.

Next, the coordinator receives, from the target node (s), a response to receipt of the time slot identification information and the target node identification information (S250). The S250 procedure may be omitted, if necessary.

Hereinafter, a downlink communication method using a shared time slot will be described by taking as an example a network node joining a star network through a PANC in a WPAN. However, star network is only an example. The scope of the present invention is not limited to the type of network.

As described in FIG. 1, the network node allocates a predetermined number of time slots for the uplink / downlink, and performs communication. Because of the limited number of time slots in the network configuration, the number of network nodes that can join the network is limited.

4 is a diagram illustrating a star network including one PANC and a plurality of network nodes. 5 is a diagram showing a beacon frame.

In the star network illustrated in FIG. 4, if the network nodes mainly perform the role of a sensor for collecting data, and mainly use only the uplink communication among the communication with the PANC, and the network nodes use the downlink If the frequency of using the communication is very low, the PANC fixedly allocating the time slot for the downlink becomes an element that wastes resources of the network due to the low frequency of use of the downlink timeslot.

If a downlink time slot to be wasted is not allocated to an individual network node, the corresponding timeslot can be utilized for the uplink timeslot. As a result, the number of new uplink timeslots that can be allocated to each network node increases, so that the time slot for network joining of the network node can increase.

Since the PANC rarely needs a downlink to transmit data to a network node, a method of allowing a certain number of downlink timeslots to be shared and then shared by the network nodes can improve the utilization efficiency of the time slot.

In order to perform downlink communication using this shared time slot, the PANC stores in the 'down GTS specification' field among the fields included in the beacon frame of FIG. 5 a target node identification information indicating a target node that is a downlink communication target, Time slot identification information indicating a time slot (e.g., the location of a shared time slot). Here, the 'down GTS specification' field is a field related to the GTS for the downlink.

The beacon frame illustrated in FIG. 5 includes a media access control (MAC) header (MHR), a MAC payload, and a MAC footer (MFR). The MHR of the beacon frame includes a 'frame control' field of 2 octets, a 'sequence number' field of 1 octet, and an 'addressing' field of 4 or 10 octets. The MAC payload of the beacon frame includes a 'superframe specification' field of 2 octets, a 'distributed synchronous multichannel extension (DSME) superframe specification' field of 2 octets, a 'channel hopping specification' field of 4 octets, Field, a 'hopping sequence length' field of one octet, a 'hopping sequence' field of a variable octet, a 'down GTS specification' field of 1 or a variable octet, and a 'beacon payload' field of a variable octet. The MFR of the beacon frame includes a 'FCS (frame check sequence)' field of 4 octets.

FIG. 6 is a diagram showing a detailed octet of the 'down GTS specification' field. And FIG. 7 is a diagram showing a shared downlink GTS.

Specifically, the 'down GTS specification' field may include a 'number of pending address' field of one octet and an 'address list' field of zero or variable octets.

The 'number of pending address' field indicates the number of network nodes that want to perform downlink communication through the downlink GTS. The information on the network node that wishes to perform the downlink communication is included in the 'address list' field.

The 'address list' field includes an 'address' field of two octets, a 'beacon ID' field of one octet, a 'superframe ID' field of one octet, and a 'slot ID' field of one octet. If the value of the 'number of pending address' field indicates one network node, the 'address list' field includes one 'address' field, one beacon ID field, one superframe ID field , And one 'slot ID' field. If the value of the 'number of pending address' field indicates a plurality of network nodes, the 'address list' field includes a plurality of 'address' fields, a plurality of 'beacon ID' fields, a plurality of 'superframe ID' And a plurality of 'slot ID' fields.

The 'address' field contains the address value of the network node that is to perform the downlink communication.

the location of the downlink GTS (or the location of the shared timeslot) used for downlink communication may be provided via the 'beacon ID' field, the 'superframe ID' field, and the 'slot ID' field. For example, in FIG. 7, when the value of the beacon ID field is BI = 1, the value of the superframe ID field is SF = 3, and the value of the slot ID field is DownGTS = 0, The downlink data can be transmitted in the first GTS (DownGTS = 0) of the link GTSs (DownGTS = 0, DownGTS = 1, ..., DownGTS = 15). 7 shows that 16 time slots included in the super frame (SF = 3) among the four super frames (SF = 0, SF = 1, ..., SF = 3) corresponding to the beacon (BI = , And a shared time slot for downlink (e.g., DownGTS = 0, DownGTS = 1, ..., DownGTS = 15).

A technique of transmitting a packet through a plurality of channels and a plurality of time slots in the above-described network environment is possible. However, how to use these resources efficiently is a problem that can not be solved because of the NP (nondeterministic polynomial time) -complete limit, also called graph coloring.

Therefore, there is a need for a method that allows a device with limited computational capability, such as a terminal, to find a heuristic solution, but not an optimal solution, for resource use or resource allocation.

More specifically, a method of performing firmware update through heuristic channel setting will be described.

First, a device (e.g., a network management device) calculates the number of source nodes (SN) having all packets, the number of available channels (CN), and the number of available time slots (TSN) belonging to one turn , The packet can be heuristically allocated to the time slot (hereinafter, 'ST10').

Next, the device (e.g., network management device) divides the number of packets (PN) of all packets that have not been received by the number of available source nodes (SN) and returns the result to the number of available channels And adjust the result to a multiple of the number of available time slots (TSN) belonging to one turn (ST11 '). The available time slots belonging to one turn may be the above described shared timeslots (e.g., DownGTS in FIG. 7).

For example, in the case where the number of available timeslots (TSN) = 4, the number of packets not received (PN) = 13, the number of source nodes (SN) = 1 and the number of available channels (E.g., the network management device) can compute PN / SN / CN = 13/1/2 = 6.5 and calculate a minimum number of timeslots 8, which is a multiple of the number of timeslots (TSN) . That is, since the number of available time slots (TSN) belonging to one turn is 4, the minimum number of time slots that can transmit all of 6.5 packets while being a multiple of 4 is 8.

Next, the device (e.g., the network management apparatus) transmits 8 packets (e.g., Pkt F, Pkt A, Pkt U, ...) in the order of the packets that are not received most by the network nodes among the transmitted packets And allocates the determined eight packets to the base one among the available channels (ST12 ').

Next, the device (e.g., the network management apparatus) may allocate unassigned packets (for example, packets not allocated in ST12) among the transmitted packets to the time slot and the available channels (hereinafter referred to as 'ST13'). . Specifically, a device (e.g., a network management apparatus) transmits a packet (e.g., packet) to an unassigned packet in the same time slot as the time slot in which the packet allocated in step ST12 is allocated, , Packets not allocated in step ST12). In this case, the device (e.g., the network management apparatus) transmits a packet that has not yet been allocated (e.g., a packet not allocated in step ST12) in the order of no duplication of received network nodes allocated in the time slot or in the order of least duplication It can be placed on additional channels (other than the base channel).

If there are a plurality of candidate packets satisfying such a placement rule, the device (e.g., the network management apparatus) can prioritize the packets satisfying the first placement condition among the plurality of candidate packets. Here, the first arrangement condition may include that the number of network nodes that can receive the packet when the packet is disposed, and the number of the network nodes that have already received the packet.

The device (e.g., network management device) may perform this additional channel placement on a channel-by-channel basis, or on a time slot basis. For example, a device (e.g., a network management device) may prioritize packets on a first channel (a first channel for different time slots) of a plurality of available channels, Lt; RTI ID = 0.0 > channel). ≪ / RTI > In another example, a device (e.g., a network management device) may place packets first in a first timeslot (channels for a first timeslot) of a plurality of available timeslots, 2 < / RTI > timeslots).

In this case, when a network node that performs packet transmission through a channel in a time slot has already been set to receive a packet through a different channel in a corresponding time slot because the packet has not been received, the device (e.g., network management apparatus) The packet to be transmitted through the network node may be excluded from the above-mentioned additional channel allocation.

If there is a packet that is not received by all the network nodes, the device (e.g., the network management apparatus) transmits a packet to a channel other than the channel in which the corresponding non-received packet is allocated among the available channels for the time slot in which the non- Additional packets may not be placed.

The method of arranging the additional channels described above includes a method of allocating additional channels (hereinafter referred to as 'method M100') so as to avoid duplication of receiving network nodes and a method of allocating additional channels such that duplication of receiving network nodes is minimized '). Hereinafter, method M100 will be described first, followed by method M200.

The network management apparatus can use a data transmission method described later for updating the firmware of the network nodes belonging to the network. Then, the network management apparatus can use the above-described network management method (e.g., the network management method of FIG. 3) for downlink communication with the network node.

8 is a diagram illustrating a data transmission method according to an embodiment of the present invention.

First, the network management device (e.g., PANC) transmits information of the packet (s) to be broadcasted and information of the time slot (s) used for broadcasting to the network nodes (S310). Here, the network node is a network node belonging to the network. For example, in the case where the network is a sensor network, the network node may be a sensor constituting the sensor network. The timeslot used for broadcasting may be the above-described shared timeslot (e.g., DownGTS in FIG. 7). The information of the time slot used for broadcasting may be the time slot identification information described above.

Next, the network management apparatus broadcasts the packet (s) to the network nodes (S320).

Next, the network management apparatus receives from the network nodes whether or not the broadcast packet (s) is received (S330).

Next, the network management device retransmits the unreceived packet (s) to the network node (s) that has not received the packet (s) (S340).

For example, when the first network node fails to receive the first packet, the first packet can be directly retransmitted from the network management apparatus. In another example, if the first network node fails to receive the first packet, the first network node may directly receive the first packet from another network node that has received the first packet. In another example, when the first network node fails to receive the first packet and the second packet, the first network node receives the first packet from the network management apparatus, and receives the second packet from the network management apparatus From another network node.

When there are a plurality of channels in one time slot, some of the plurality of channels may be used by the network node to receive packets from the network management device, and another part of the plurality of channels may be transmitted from the other network node May be used to receive packets. For example, in the case where there are four channels in one time slot, channel 1 and channel 2 of the four channels are allocated to the first network node, the second network node, and the third network node, , And channel 3 and channel 4 of the four channels can be used for the purpose of transmitting packets between network nodes. In this case, the network management apparatus can transmit the unreceived packet (s) to the first network node, the second network node, and the third network node using channel 1 and channel 2. And the first network node, the second network node, and the third network node may transmit the packet (s) to each other using channel 3 and channel 4.

For data transmission in such a network, the network management device may generate a data transmission schedule (e.g., information about the time slot and channel in which the packet is placed) and send the data transmission schedule to the network nodes. The network node can perform data transmission with the network management apparatus or perform data transmission with another network node according to the received data transmission schedule.

9 is a diagram illustrating a method by which a network management apparatus generates a data transmission schedule according to an embodiment of the present invention.

The network management device (e.g., PANC) determines the target node (s) to retransmit unreceived packet (s) from the network management device (S410).

Next, the network management apparatus determines a transmission network node (hereinafter, referred to as 'transmission node') and a reception network node (hereinafter referred to as 'reception node') (S420) .

Next, the network management apparatus determines a data retransmission schedule for unreceived packet (s) based on the determined target node (s), the transmission node (s), and the receiving node (s) (S430).

Hereinafter, a data transmission method according to an embodiment of the present invention will be described in more detail.

The network management device may be a PANC, and the network node may be a sensor. The PANC may transmit common data for firmware updates to a plurality of sensors present in the network. It is assumed that there are 20 network nodes (e.g., ND1 to ND20) to which firmware data is downloaded. It is assumed that the data unit of the firmware data is a packet and the firmware data is composed of 26 packets (for example, Pkt A, Pkt B, ..., Pkt Z). Under this assumption, the overall process of firmware data transfer for firmware update can proceed as illustrated in Table 1 below.

step Section / channel / Pkt # Sender -> receiver Detailed description T1 CAP / CH0 / Pkt CC0 PANC-> ALL Notify start of firmware (F / W) update
(CH = 0, Slot List = 2 to 5, NumberOfPkt = 26, PktList = A to Z) T2 GTS / CH0 / Pkta PANC-> ALL Pkta T3 GTS / CH0 / Pkt B PANC-> ALL Pkt B ... T4 GTS / CH0 / Pkt Z PANC-> ALL Pkt Z T5 GTS / CH0 / Pkt GC1 1-> PANC - Report missing part of F / W Update (Pkt T, R, E)
- Not shown in Table 1 T6 GTS / CH0 / Pkt GC2 2-> PANC - Report missing part of F / W Update (Pkt T, B, R, E, C)
- Not shown in Table 1 T7 GTS / CH0 / Pkt GC3 3-> PANC - Report missing part of F / W Update (Pkt T, B, O, R, E, C)
- Not shown in Table 1 T8 GTS / CH0 / Pkt GC4 4-> PANC (Fkt, F, T, B, O, S, R, E, C)
- Not shown in Table 1 ... ... ... T9 GTS / CH0 / Pkt GC20 20-> PANC - Report missing parts in F / W Update (Pkt F, A, U, L, T, I, V)
- Not shown in Table 1 T10 ≪ PANC retransmission scheduling for untransmitted packets > T11 CAP / CH0 / Pkt CC30 PANC-> ALL F / W Update to notify the start of continuation
(CH = 0, SlotList = 2 to 5, NumberOfPkt = 8, PktList = F (0), A (@ 0), U (@ 0), S (@ 0), R (@ 0))

(CH = 1, SlotList = 2 to 5, NumberOfPkt = 8, PktList = N / A, C (1), E (7), B (1), I (12) , N / A, N / A) T12 GTS / CH0 / Pkt F
GTS / CH1 / Pkt N / A PANC-> ALL
N / A-> N / A Pkt F (TO 1 ~ 20)
N / A GTS / CH0 / Pkta
GTS / CH1 / Pkt C PANC-> ALL
1-> ALL Pkta (TO 6 ~ 20)
Pkt C (TO 2 ~ 4) T13 GTS / CH0 / Pkti
GTS / CH1 / Pkt E PANC-> ALL
7-> ALL Pkti (TO 8 ~ 20)
Pkt E (TO 1-6) ... ... ... T14 GTS / CH0 / Pkt R
GTS / CH1 / Pkt N / A PANC-> ALL
N / A-> N / A Pkt R (TO 1-8)
N / A

In Table 1, Pkt CC0 is a packet for notifying the start of firmware update, and CC is a Command message in the CAP. Pkt CC30 is a packet for notifying the start of firmware update continuation. Pkt GC1 to GC20 are packets for reporting missing parts in the firmware update, and GC is a Command message in the GTS. Pkt A ~ Pkt Z are packets constituting firmware data respectively. In Table 1, CH0 and CH1 are channels existing in one time slot. The PANC may be network node 0.

Each of the steps T1 to T14 of Table 1 will be described below.

First, in step T1, the PANC transmits a Pkt CC0 packet to the network nodes ND1 to ND20 over the CH0 channel of a time slot (e.g., Slot # 0) belonging to the CAP section. The Pkt CC0 packet includes a 'CH parameter' indicating a channel used for firmware data transmission, a 'SlotList parameter' indicating a time slot used for data transmission, a 'NumberOfPkt parameter' indicating the number of packets to be transmitted, And " PktList parameter " indicating order. In Table 1, it is illustrated that 26 packets will be transmitted in the order of Pkt A to Pkt Z through channel # 0 and timeslots # 2-5.

Next, in steps T2 to T4, the PANC transmits firmware data packets Pkt A to Pkt Z to all the nodes ND1 to ND20 through broadcasting. Specifically, the PANC can transmit data on a turn basis. In this specification, a turn may indicate the unit in which the PANC specifies the sender and receiver in each GTS interval.

One turn may consist of a CAP section, which is a shared section, and a GTS section, which is a full section. For example, the CAP interval may be composed of two time slots. In CAP section, it is possible to send / receive by any entity. For example, the GTS interval may be composed of four time slots. In the GTS section, transmission / reception can be performed only by a predetermined network node.

For example, as illustrated in the following Table 2, in the time slot # 2 (Slot # 2) among the six time slots (Slot # 0 to Slot # 5) belonging to the first turn The packet Pkt A can be broadcast to all the network nodes ND1 to ND20 by being transmitted from the network node 0 (ND0), that is, from the PANC (Pkt A (@ 0)). In this way, the PANC can transmit all packets from the packet Pkt A to the packet Pkt Z to all the network nodes ND1 to ND20 through the broadcast method. For this data transfer, channel CH0 may be used. Tables 3 to 5 illustrate the turn table for such data transmission. In the table below, channel CH0 may be a common channel.

Turn # 1 CAP GTS Slot # 0 Slot # 1 Slot # 2 Slot # 3 Slot # 4 Slot # 5 CH 0 Pkt CC0 Pkta (@ 0) Pkt B (@ 0) Pkt C (@ 0) Pkt D (@ 0)

Turn # 2 CAP GTS Slot # 0 Slot # 1 Slot # 2 Slot # 3 Slot # 4 Slot # 5 CH0 Pkt E (@ 0) Pkt F (@ 0) Pkt G (@ 0) Pkt H (@ 0)

Turn # 3 CAP GTS Slot # 0 Slot # 1 Slot # 2 Slot # 3 Slot # 4 Slot # 5 CH0 Pkt I (@ 0) Pkt J (@ 0) Pkt K (@ 0) Pkt L (@ 0)

Turn # 6 CAP GTS Slot # 0 Slot # 1 Slot # 2 Slot # 3 Slot # 4 Slot # 5 CH0 Pkt W (@ 0) Pkt X (@ 0) Pkt Y (@ 0) Pkt Z (@ 0)

Referring back to Table 1,

In steps T5 and T9, the network nodes report whether they have received data in the PANC. Specifically, the network node can report the number of firmware packets it has not received to the PANC using a bitmap or an index. Together, the network node may report its available channel number, available battery level, and unused time slot number to the PANC. The network node may also report to the PANC information indicating the strength of the wireless signal of the other neighboring nodes that can be received and the quality of the wireless signal. The information indicating the strength of the radio signal and the quality of the radio signal of other neighboring nodes that can be received includes the received signal strength indicator (RSSI), the link quality index (LQI), and the transmission / do.

In step T10, the PANC checks whether the network nodes receive the packet, and then generates a data transmission schedule for retransmission of the non-received packet.

For example, as illustrated in Table 6 below, the PANC calculates the number (Pkt #) of network nodes that have not received a packet for each packet ('Pkt #') using the non- Num Of Missed Nodes') and a list of network nodes that did not receive the packet ('Missed Node List').

Pkt # Num Of Missed Nodes Missed Node List Pkt F 17 ND14, ND15, ND6, ND7, ND8, ND9, ND10, ND11, ND12, ND13, ND14, Pkta 15 ND6, ND7, ND8, ND9, ND10, ND11, ND12, ND13, ND14, ND15, Pkti 13 ND8, ND9, ND10, ND11, ND12, ND13, ND14, ND15, ND16, ND17, ND18, ND19, ND20 Pkt L 11 ND10, ND11, ND12, ND13, ND14, ND15, ND16, ND17, ND18, ND19, ND20 Pkt T 10 ND1, ND2, ND3, ND4, ND5, ND6, ND7, ND8, ND9, ND10 Pkt B 8 ND2, ND3, ND4, ND5, ND6, ND7, ND8, ND9 Pkt O 8 ND3, ND4, ND5, ND6, ND7, ND8, ND9, ND10 Pkt S 8 ND4, ND5, ND6, ND7, ND8, ND9, ND10, ND11 Pkt R 8 ND1, ND2, ND3, ND4, ND5, ND6, ND7, ND8 Pkt E 6 ND1, ND2, ND3, ND4, ND5, ND6 Pkt C 3 ND2, ND3, ND4 Pkt I 2 ND19, ND20 Pkt V One ND20

In Table 6, it is exemplified that the 17 network nodes (ND4 to ND20) did not receive the packet Pkt F.

With reference to Table 6, the PANC can create a packet retransmission schedule for network nodes. It is assumed that two channel resources (e.g., CH0, CH1) are used. If more channels are available, several channels can be used at a time.

In Table 6, the packet with the most errors among the packets (i.e., the packet having the largest 'Num Of Missed Nodes') can be retransmitted to the network nodes first.

Table 7 below is a time table showing a retransmission schedule.

The packets illustrated in Table 6 may be filled in Table 7 in the order of the most likely fragments (packets) in which errors occur.

The PANC, represented by network node 0 (ND0), retransmits the packet to the network nodes using channel CH0. If there is a network node that has received all fragments (packets), the corresponding network node can transmit packets to other network nodes using the remaining channel resources (eg, CH0 and other channels).

Turn # 12 CAP GTS Slot # 0 Slot # 1 Slot # 2 Slot # 3 Slot # 4 Slot # 5 CH0 Pkt CC30
Pkt F (@ 0) Pkta (@ 0) Pkti (@ 0) Pkt L (@ 0) CH1 Pkt C (@ 1) Pkt E (@ 7) Pkt B (@ 1)

Table 7 illustrates a case in which the PANC performs transmission of the packet Pkt CC30 on the channel CH0 in a time slot (e.g., Slot # 0) belonging to the CAP section of the turn (Turn # 12).

Table 7 shows the case where the PANC retransmits the packet Pkt F having the largest 'Num Of Missed Nodes' through the channel CH0 in the time slot 2 (Slot # 2) belonging to the turn (Turn # 12) Pkt F (@ 0)) is illustrated.

17 network nodes ND4 to ND20 have not received the packet Pkt F and the 17 network nodes ND4 to ND20 receive the packet Pkt F from the PANC using the channel CH0 of the time slot 2 (Slot # 2) shall. As a result, packet transmission between network nodes is not performed in channel CH1 of time slot 2 (Slot # 2).

Of the packets illustrated in Table 6, the fragment (packet) with the largest error following Pkt F is Pkt A, and the PANC also transmits the packet Pkt A (i.e., Pkt A (@ 0)). At this time, referring to Table 6, the PANC can schedule packet transmission between the network nodes receiving the packet Pkt A to proceed in the channel CH 1 of the time slot 3 (Slot # 3). Specifically, referring to Table 6, the PANC can determine the sender to perform packet transmission among the network nodes receiving the packet Pkt A. For example, referring to Table 6, the PANC can select a network node ND1 having the largest number of pieces (packets) among the network nodes ND1 to ND5 that have received the packet Pkt A as a sender.

Alternatively, the PANC may predict a transmission result to be performed in a previous time slot of a time slot in which a network node selected from the network nodes ND1 to ND5 receiving the packet Pkt A performs transmission, A network node that is supposed to have many packets can be determined as the sender. For example, in Table 7, since the selected network node among the network nodes ND1 to ND5 performs packet transmission in the time slot 3 (Slot # 3), the PANC transmits the previous time slot of the time slot 3 A packet retransmission result performed in time slot 2 (Slot # 2) can be predicted, and a network node estimated to hold the largest number of packets based on the prediction can be determined as a transmission node. The PANC can perform the transmission result prediction based on the RSSI / LQI / transmission / reception success rate between the transmitting and receiving nodes. Also, the sender can be allocated in the order of the downlink GTS slot ID used in the 1: 1 communication with the PANC. At this time, the number of nodes holding the data fragment in which the error occurs can be relatively quickly reduced, and therefore, the number of candidate senders that can be transmitted can increase relatively quickly.

Next, when the sender (or the transmission node) is determined, the PANC selects the network nodes ND1 to ND5 holding the packet Pkt A by the remaining network nodes (e.g., ND2, ND3, ND4, ND5) The packet that has not received the most (ie, the fragment in which the error occurred) can be selected as the packet to be transmitted by the sender. For example, since 75% (ND2, ND3, ND4) of the network nodes ND2, ND3, ND4 and ND5 did not receive the packet Pkt C, the PANC sends the packet Pkt C to the sender Can be determined as the packet to be transmitted (i.e., Pkt C (@ 1)).

Thus, the sender / receiver for the channels CH0 and CH1 of the time slot 3 (Slot # 3) belonging to the turn (Turn # 12) illustrated in Table 7 is determined. Likewise, through this method, the remainder of Table 7 can be filled. For example, in Table 7, the packet Pkt U is transmitted by the PANC over the channel CH0 in the time slot 4 (Slot # 4) belonging to the turn (Turn # 12), the packet Pkt E is transmitted through the channel CH1 to the network node RTI ID = 0.0 > ND7). ≪ / RTI > In another example, in Table 7, a packet Pkt L is transmitted by the PANC over the channel CH0 in the time slot 5 (Slot # 5) belonging to the turn (Turn # 12) (ND1). ≪ / RTI >

Similarly, the PANC can generate a retransmission schedule table for the next turn (Turn # 13) in the same manner, which is illustrated in Table 8.

The packet retransmission can be performed through the required number of turns so that there is no packet that the network nodes ND1 to ND20 did not receive.

Turn # 13 CAP GTS Slot # 0 Slot # 1 Slot # 2 Slot # 3 Slot # 4 Slot # 5 CH0 Pkt T (@ 0) Pkt O (@ 0) Pkt S (@ 0) Pkt R (@ 0) CH1 Pkt I (@ 12) Pkt V (@ 12)

For example, in Table 8, a packet Pkt T is transmitted by a PANC over a channel CH0 in a time slot 2 (Slot # 2) belonging to a turn (Turn # 13), a packet Pkt I is transmitted through a channel CH1 to a network node RTI ID = 0.0 > ND12). ≪ / RTI > As another example, in Table 8, a packet Pkt O is transmitted by the PANC over the channel CH0 in the time slot 3 (Slot # 3) belonging to the turn (Turn # 13), the packet Pkt V is transmitted through the channel CH1 to the network node (ND12). ≪ / RTI > For example, in Table 8, the packet Pkt S is transmitted by the PANC over the channel CH0 in the time slot 4 (Slot # 4) belonging to the turn (Turn # 13) And packet PktR is transmitted by the PANC over channel CH0 in slot 5 (Slot # 5).

Next, a method (method M200) for arranging additional channels so as to minimize redundancy will be described.

In the above-described transmission scheduling, packets to be simultaneously transmitted through different channels in one time slot do not overlap with each other.

It may happen that the PANC can not be scheduled so that the recipients do not overlap. That is, there may occur a case where the PANC performs scheduling in which the reception subject is allowed to overlap.

Specifically, the PANC can allocate unassigned packets to a channel different from the channel in which the already allocated packet is placed, in the same time slot as the time slot in which the already allocated packet is placed. In this case, the PANC can allocate yet unassigned packets to additional channels in the order of no overlap of the receiving network nodes assigned to that time slot or least duplication. If there are a plurality of candidate packets satisfying such a placement rule, the PANC can give priority to packets satisfying the first placement condition among the plurality of candidate packets. As described above, the first arrangement condition may include that the number of network nodes that can receive the packet when the packet is disposed, and the number of the network nodes that have already received the packet.

The PANC can perform this additional channel allocation on a channel-by-channel basis, or on a timeslot basis. The former is called 'additional channel allocation based on channel priority' and the latter is called 'additional channel allocation based on time slot priority'. For example, in the case of additional channel placement based on channel preference, the PANC first places the packets on the first channel (the first channel of the different timeslots) of the plurality of channels and then the second channel The second channel of the slots). For another example, in the case of additional channel placement based on timeslot priority, the PANC first places the packets in the first timeslot (the channels of the first timeslot) of the plurality of timeslots, It is possible to place other packets in the slot (the channels of the second time slot).

If additional channel placement based on time slot preference is used, Table 7 can be changed as shown in Table 9 below. In Table 9, it is assumed that three channels (e.g., CH0, CH1, CH2) are used.

ND1 of the network node that has already received the packet Pkt F can transmit packets Pkt C, Pkt I, and Pkt V on the channel CH1 of the time slot Slot # 2, ND2 and ND3 can transmit the packets Pkt C, Pkt I and Pkt V can be transmitted in CH1. A packet that can be transmitted to the largest number of network nodes among the packets Pkt C, Pkt I, and Pkt V, while having a small number of network nodes that have already received the packet can be selected. For example, the packet Pkt C may be selected. The selected packet Pkt C may be scheduled to be transmitted on the channel CH1 of the time slot (Slot # 2) by the network node ND1. In this case, the receivers of the packet Pkt C transmitted on the channel CH1 of the time slot (Slot # 2) and the receivers of the packet Pkt F transmitted on the channel CH0 of the time slot (Slot # 2) are partially overlapped. For example, since the network node ND4 has not received both the packet Pkt C and the packet Pkt F, the network node ND4 as the receiver of the packet Pkt F and the packet Pkt C transmitted in the time slot (Slot # 2) Overlapping.

In this case, the redundant network node ND4 may be scheduled to receive the packet Pkt F over CH0, which is the upper channel among the channels (CH0, CH1) registered as the receiver, for efficient packet reception.

On the other hand, a packet can also be allocated to the channel CH2 among the channels CH0, CH1, and CH2 of the time slot (Slot # 2), but since there are no more network nodes to receive the packet in the time slot (Slot # 2) It is not necessary for the sender to be placed in the channel CH2 of the slot (Slot # 2). For the same reason, it is not necessary for the sender to be further placed in the channels CH1 and CH2 of the timeslot (Slot # 3), the channel CH2 of the timeslot (Slot # 4), and the channel CH2 of the timeslot (Slot # 5) . For example, in Table 9, the packet Pkt F is transmitted by the PANC over the channel CH0 in the time slot 2 (Slot # 2) belonging to the turn (Turn # 12) And the packet Pkt C is transmitted by the network node ND1 via the channel CH1 in the second slot (Slot # 2). For another example, Table 9 illustrates a case where a packet Pkt A is transmitted by the PANC over the channel CH0 in time slot 3 (Slot # 3) belonging to the turn (Turn # 12). In another example, in Table 9, the packet Pkt U is transmitted by the PANC over the channel CH0 in the time slot 4 (Slot # 4) belonging to the turn (Turn # 12) And the packet Pkt E is transmitted by the network node ND7 through the channel CH1 in the slot 4 (Slot # 4). In another example, in Table 9, the packet Pkt L is transmitted by the PANC over the channel CH0 in the time slot 5 (Slot # 5) belonging to the turn (Turn # 12) And a packet PktR is transmitted by the network node ND9 through the channel CH1 in the slot 5 (Slot # 5).

Turn # 12 CAP GTS Slot # 0 Slot # 1 Slot # 2 Slot # 3 Slot # 4 Slot # 5 CH0 Pkt CC30 Pkt F (@ 0) Pkta (@ 0) Pkti (@ 0) Pkt L (@ 0) CH1 Pkt C (@ 1) x Pkt E (@ 7) Pkt R (@ 9) CH2 x x x x

Next, the PANC specifies a shared time slot, a used channel, a packet distributor (sender), and a packet receiver for each packet of firmware data in the retransmission schedule information generated in step T10, and transmits the retransmission schedule information to the network nodes have. The operation of this PANC can be expressed as a PANC transmission performed in step T11 of Table 1 (GTS / CH0 / Pkt CC30). That is, the PANC can transmit the packet Pkt CC30 to the network nodes through the channel CH0 of the time slot belonging to the CAP interval.

Referring again to Table 1, in step T11, the PANC informs all network nodes that the retransmission of firmware data is to start. Specifically, in the description of step T11 in Table 1, "CH = 0, SlotList = 2 to 5, NumberOfPkt = 8, PktList = F (@ 0), A (Slot # 2 ~ Slot # 5) of channel CH0 are used to transmit 8 packets (# 0 ~ # 0), T (@ 0), O (@ 0), S PANC is Pkt A, PANC is Pkt A, PANC is Pkt U, PANC is Pkt L, PANC is Pkt T, PANC is Pkt O, PANC is Pkt S, and PANC means that Pkt R is transmitted sequentially (distribution order and distributor).

(CH = 1, SlotList = 2 to 5, NumberOfPkt = 8, PktList = N / A, C (1), E (7), B (1) , 8 (I 12), V 12, N / A, N / A "means that eight packets are transmitted using time slots Slot # 2 to Slot # 5 of the channel CH1, In the first timeslot, there is no packet transmission. In the next time slots, the network node ND5 transmits a packet Pkt C, the network node ND7 transmits a packet Pkt E, the network node ND1 transmits a packet Pkt B, ND12) transmits the packet PktI and the network node ND12 sequentially transmits the packet PktV (distribution order and distributor).

In steps T12 to T14, the PANC and each network node perform transmission of the firmware data packet according to the retransmission schedule. Specifically, each network node can distribute the packet received by itself in the time slot and channel specified by the retransmission schedule, and can receive the packet that it has not received in the time slot and channel designated by the retransmission schedule.

Thereafter, each network node can report back to the PANC an unreceivable packet. Then, the PANC recalculates the retransmission schedule and allocates the sender and the receiver by time slot and channel, and notifies each network node of the allocation. Then, the PANC and each network node can re-transmit the firmware data packet according to the recalculated retransmission schedule.

The packet retransmission described above can be terminated when all network nodes receive all the firmware data packets. The packet retransmission described above can be repeated until all the network nodes receive all the firmware data packets.

10 shows a network management apparatus NC100 according to an embodiment of the present invention. The network management apparatus NC 100 for managing a plurality of network nodes may be the above-described PANC, coordinator, and the like. Specifically, the network management apparatus NC100 may include a communication unit NC110 and a processor NC120.

The communication unit NC110 may include general communication components used for communication of the network management device in the network. Specifically, the communication unit NC110 can transmit / receive data to / from at least one network node subscribed to the network using time slots.

The processor NC 120 may use the network management method described above to generate timeslot identification information indicating a timeslot allocated for the downlink of the target node. Then, the processor NC120 can transmit time slot identification information to the target node using the communication unit NC110.

The processor NC 120 may broadcast at least one data unit to the network nodes subscribed to the network using the communication unit 110. [ Here, the data unit may be a packet. However, this is merely an example, and the present invention can be applied even when the data unit is not a packet.

The processor NC 120 can receive unreceived data information indicating packets that the network nodes have not received among the transmitted packets from the network nodes using the communication unit 110. [

The processor NC 120 may retransmit at least one packet to at least one network node based on the missing data information. Specifically, the processor NC 120 may generate a retransmission schedule for packet retransmission, as described above.

The processor NC 120 may transmit information of a packet to be broadcasted and information of a time slot and a channel used for broadcasting to network nodes subscribed to the network before broadcasting the packet.

The processor NC 120 may use the GTS to broadcast packets to network nodes.

The processor (NC 120) may generate a transmission schedule for packet transmission between network nodes based on the unreceived data information. The processor NC 120 may send the transmission schedule to at least one network node. Specifically, the transmission schedule includes information of a network node (e.g., a first network node) that has received the broadcasted packet, information of a network node (e.g., a second network node) that receives a packet from the first network node, Information of a packet transmitted by the network node to the second network node, information of a time slot in which the packet is transmitted, and information of a channel through which the packet is transmitted.

The processor NC120 may generate time slot identification information indicating a time slot allocated to the downlink of the target node for retransmission of the packet (hereinafter referred to as " retransmission target node ") and transmit the time slot identification information to the retransmission target node have.

The processor NC 120 may generate target node identification information indicating the retransmission target node and may transmit the target node identification information to the retransmission target node. Specifically, the processor NC 120 may transmit the target node identification information and the time slot identification information to the retransmission target node using the same time slot. Alternatively, the processor NC 120 may transmit the target node identification information and the time slot identification information to the retransmission target node using different timeslots.

As described above, the time slot allocated for the downlink of the retransmission target node may be a time slot guaranteed for allocation for the retransmission target node. The timeslot allocated for the downlink of the retransmission target node may be a shared timeslot (e.g., DownGTS).

The time slot identification information may include at least one of a beacon ID and a superframe ID and a slot ID.

Based on the above description, the transmission method of the network management apparatus NC100 and the firmware update method of the network management apparatus NC100 will be described again.

The network management apparatus NC100 can broadcast a plurality of packets using a plurality of shared time slots and a base channel (e.g., CHO) shared by a plurality of network nodes for downlink communication. Specifically, before broadcasting a plurality of packets, the network management apparatus NC100 transmits information on a plurality of shared time slots (e.g., Slot List in Table 1), information on a basic channel (e.g., CHO) The number of packets (e.g., NumberOfPkt in Table 1) and the transmission order of a plurality of packets (e.g., PktList in Table 1) can be broadcast on a base channel (e.g., CH0) in a time slot belonging to the CAP interval .

The network management apparatus NC100 can identify one or more unreceived packets not received by a plurality of network nodes among a plurality of broadcasted packets. Specifically, the network management apparatus NC100 may receive, from each of the plurality of network nodes, an unreceived packet bitmap indicating one or more unreceived packets of each of the plurality of network nodes. The network management apparatus NC 100 can confirm the number of unreceived nodes (e.g., 'Num Of Missed Nodes' in Table 6) that failed to receive one or more unreceived packets among a plurality of network nodes, by one or more unreceived packets.

The network management apparatus NC100 may determine (or schedule) distribution time slots and distribution channels for transmission of one or more unreceivable packets, and one or more unreceived packets. Specifically, the network management apparatus NC100 may determine the number (e.g., PN) of one or more missing packets, the number of channels (e.g., CN) for one downlink timeslot, TSN), it is possible to calculate the maximum number of packets (e.g., the minimum number of timeslots calculated in step ST11) allocated to the distribution channel. The network management apparatus NC100 determines whether or not at least one of the one or more unrecorded packets is received based on the number of unreceived nodes (e.g., 'Num Of Missed Nodes' in Table 6) and the maximum number of packets (for example, And determine the packet to be allocated to the distribution channel (e.g., CH0).

In addition, the network management apparatus NC100 may determine that a packet (e.g., Pkt F) having the largest number of unreceived nodes (e.g., 'Num Of Missed Nodes' in Table 6) (E.g., CH1) for a distribution time slot (e.g., Slot # 2 in Table 7) when the base station is allocated to a base channel (e.g., CHO) .

In addition, the network management apparatus NC100 may further include a distribution channel for a time slot (e.g., Slot # 3) (e.g., slot # 3) so that receivers of packets allocated to the same time slot (e.g., Slot # 3) 0.0 > CH1) < / RTI > The network management apparatus NC100 may include a base channel (e.g., CH0) and an additional channel (e.g., CH1) for a distribution time slot (e.g., Slot # 3 in Table 7). The network management apparatus NC100 is a network that has already received a packet (e.g., Pkt A) among a plurality of network nodes, in the case where a packet (e.g., Pkt A) of one or more unreceived packets is assigned to a base channel (E.g., ND1) as a distributor to transmit a packet (e.g., Pkt C) of the one or more missing packets over an additional channel (e.g., CH1).

The network management apparatus NC100 may generate transmission schedule information including information on the distributor, the distribution time slot, and the distribution channel, and then broadcast using the basic channel CH0. Here, the transmission schedule information may further include a maximum number of packets (e.g., the minimum number of timeslots calculated in step ST11) and a transmission order of one or more unreceived packets (e.g., PktList in Table 1). In the case where the distribution channel is a basic channel (e.g., CH0), a packet allocated to a base channel (e.g., CH0) among one or more unreceived packets is transmitted by the network management apparatus NC100, CH1), a packet assigned to an additional channel (e.g., CH1) of one or more unreceived packets may be transmitted by at least one of the plurality of network nodes.

The plurality of network nodes may be a plurality of sensors existing in the sensor network, and the plurality of packets may be included in firmware data for updating the firmware of the plurality of sensors.

11 is a diagram of a computing device, in accordance with an embodiment of the present invention. The computing device TN100 of FIG. 11 may be a network node, a network management device, a coordinator, a PANC, etc., as described herein.

In the embodiment of FIG. 11, the computing device TN100 may include at least one processor (TN 110), a communications device (TN 120) connected to the network to perform communications, and a memory (TN 130). Further, the computing device TN100 may further include a storage device TN140, an input interface device TN150, an output interface device TN160, and the like. The components included in the computing device TN100 may be connected by a bus (TN170) and communicate with each other.

The processor TN110 may execute a program command stored in at least one of the memory TN130 and the storage device TN140. The processor TN110 may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to embodiments of the invention are performed. The processor TN110 may be configured to implement the procedures, functions, and methods described in connection with the embodiments of the present invention. The processor TN110 may control each component of the computing device TN100.

Each of the memory TN130 and the storage device TN140 may store various information related to the operation of the processor TN110. Each of the memory TN130 and the storage device TN140 may be constituted of at least one of a volatile storage medium and a nonvolatile storage medium. For example, the memory TN130 may be configured with at least one of a read only memory (ROM) and a random access memory (RAM).

The communication device (TN 120) can transmit or receive a wired signal or a wireless signal.

On the other hand, the embodiments of the present invention are not only implemented by the apparatuses and / or methods described so far, but may also be realized through a program realizing a function corresponding to the configuration of the embodiment of the present invention or a recording medium on which the program is recorded And such an embodiment can be easily implemented by those skilled in the art from the description of the embodiments described above. Specifically, methods (e.g., network management methods, data transmission methods, transmission schedule generation methods, etc.) according to embodiments of the present invention may be implemented in the form of program instructions that can be executed through various computer means, Lt; / RTI > The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions to be recorded on the computer readable medium may be those specially designed or constructed for an embodiment of the present invention or may be known and available to those of ordinary skill in the computer software arts. The computer readable recording medium may comprise a hardware device configured to store and execute program instructions. For example, the computer-readable recording medium can be any type of storage media such as magnetic media such as hard disks, floppy disks, and magnetic tape, optical media such as CD-ROMs, DVDs, floptical disks, Such as magneto-optical media, ROM, RAM, flash memory, and the like. Program instructions may include machine language code such as those generated by a compiler, as well as high-level language code that may be executed by a computer via an interpreter or the like.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, And falls within the scope of the invention.

Claims (20)

A packet transmission method of a network management apparatus,
Broadcasting a plurality of packets using a plurality of shared timeslots and a base channel shared by a plurality of network nodes for downlink communication;
Identifying one or more unreceived packets not received by the plurality of network nodes among the plurality of packets;
Determining a distribution time slot and distribution channel for transmission of the at least one unreceived packet, and a distribution time slot for transmission of the at least one unreceived packet; And
Broadcasting the transmission schedule information including the distributor, information on the distribution time slot, and information on the distribution channel using the basic channel
Lt; / RTI > The method according to claim 1,
Wherein identifying the one or more missing packets comprises:
Receiving the at least one unreceived packet from the plurality of network nodes, and checking the number of unreceived nodes for each of the at least one unreceived packet
And transmitting the packet. 3. The method of claim 2,
Wherein the determining comprises:
Calculating a maximum number of packets to be allocated to the distribution channel using the number of the at least one unrecognized packet, the number of channels for one downlink time slot, and the number of shared time slots; And
Determining a packet to be allocated to the distribution channel among the one or more unreceived packets based on the number of unreceived nodes and the maximum number of packets
And transmitting the packet. The method according to claim 1,
Wherein the determining comprises:
Determining a first timeslot of the plurality of shared timeslots as the distribution timeslot; And
Determining a packet to be allocated to the distribution channel for the first time slot so that receivers of packets assigned to the first time slot among the one or more unreceived packets are not duplicated
And transmitting the packet. The method according to claim 1,
Wherein the distribution channel for the distribution time slot comprises the base channel and the first channel,
Wherein the determining comprises:
A first node of the plurality of network nodes receiving the first packet and a second node of the one or more non-received packets to the first channel when the first one of the at least one non- Steps to be taken as the distributor to transmit over the channel
And transmitting the packet. The method according to claim 1,
Before broadcasting the plurality of packets,
Wherein the information on the plurality of shared time slots, the information on the basic channel, the number of the plurality of packets, and the transmission order of the plurality of packets are stored in a time slot belonging to a contention access period (CAP) Steps to Broadcast Through
Further comprising: The method according to claim 1,
Wherein identifying the one or more missing packets comprises:
Receiving, from each of the plurality of network nodes, an unreceived packet bitmap indicating at least one unreceived packet of each of the plurality of network nodes; And
Receiving, from each of the plurality of network nodes, information indicating a strength of a wireless signal and a quality of a wireless signal of a peripheral node of the plurality of network nodes
And transmitting the packet. 3. The method of claim 2,
Wherein the distribution channel for the first time slot of the distribution time slot includes the base channel and the first channel,
Wherein the determining comprises:
When a first packet having the largest number of the unreceived nodes among the one or more unreceived packets is allocated to the basic channel for the first timeslot, a packet is not transmitted on the first channel for the first timeslot Scheduling to avoid
And transmitting the packet. The method of claim 3,
Wherein the transmission schedule information includes at least one of the maximum number of packets and the transmission order of the at least one non-
Further comprising: The method according to claim 1,
Wherein, when the distribution channel is the basic channel, a packet allocated to the basic channel among the one or more unreceived packets is transmitted by the network management apparatus,
Wherein a packet assigned to the first one of the one or more unreciprocated packets is transmitted by at least one of the plurality of network nodes when the distribution channel is a first channel different from the basic channel. A network management apparatus for managing a plurality of network nodes,
A communication unit for broadcasting a plurality of packets using a plurality of shared time slots and a basic channel shared by the plurality of network nodes for downlink communication; And
Determine one or more unreceived packets not received by the plurality of network nodes of the plurality of packets, determine a distribution time slot and distribution channel for transmission of the one or more unreceived packets and a distributor to transmit the one or more unreceived packets A processor for generating transmission schedule information including information about the distributor, information about the distribution time slot, and information about the distribution channel,
And the communication unit broadcasts the transmission schedule information using the basic channel. 12. The method of claim 11,
The processor comprising:
For each of the at least one unreceived packet, the number of unreceived nodes not receiving the at least one unreceived packet among the plurality of network nodes,
Network management device. 13. The method of claim 12,
The processor comprising:
Calculating a maximum number of packets to be allocated to the distribution channel using the number of the at least one unrecognized packet, the number of channels for one downlink time slot, and the number of the plurality of shared time slots, Determining a packet to be allocated to the distribution channel among the one or more unreceived packets based on the maximum number of packets,
Network management device. 12. The method of claim 11,
The processor comprising:
Wherein the first timeslot is determined to be a first time slot of the plurality of shared timeslots in the distribution time slot, Determining a packet to be allocated to the distribution channel,
Network management device. 12. The method of claim 11,
Wherein the distribution channel for the first time slot of the distribution time slot includes the base channel and the first channel,
The processor comprising:
Wherein a first one of the plurality of network nodes having the first packet is assigned to the first one of the plurality of network nodes in a first time slot of the first timeslot, Determining as a distributor to perform packet transmission using the channel,
Network management device. 13. The method of claim 12,
Wherein the distribution channel for the first time slot of the distribution time slot includes the base channel and the first channel,
The processor comprising:
Scheduling such that packets are not transmitted on the first channel of the first timeslot if a first packet with the highest number of unreceived nodes among the one or more unreceived packets is assigned to the base channel of the first timeslot doing,
Network management device. 12. The method of claim 11,
Wherein,
Wherein, before broadcasting the plurality of packets, information on the plurality of shared time slots, information on the basic channel, number of the plurality of packets, and transmission order of the plurality of packets are recorded in a contention access period In a time slot belonging to the base station,
Network management device. 12. The method of claim 11,
Wherein the plurality of network nodes are a plurality of sensors existing in a sensor network,
Wherein the plurality of packets are included in firmware data for updating firmware of the plurality of network nodes,
Network management device. A method of updating a firmware for a plurality of sensors by a personal area network (PAN) coordinator,
Broadcasting a plurality of packets for updating the firmware of the plurality of sensors using a plurality of shared time slots and a base channel shared by the plurality of sensors;
Identifying one or more unreceived packets not received by the plurality of sensors among the plurality of packets; And
Scheduling a distribution time slot and a distribution channel for transmission of the at least one unreceived packet, and at least one unreceived packet,
Wherein a packet assigned to the first one of the one or more unrecognized packets is transmitted by at least one of the plurality of sensors when the distribution channel is a first channel different from the basic channel,
How to update the firmware. 20. The method of claim 19,
Before broadcasting the plurality of packets,
Wherein the information on the plurality of shared time slots, the information on the basic channel, the number of the plurality of packets, and the transmission order of the plurality of packets are stored in a time slot belonging to a contention access period (CAP) Steps to Broadcast Through
The firmware update method further comprising:

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