KR102160963B1 - Routing device and method - Google Patents

Abstract

A routing apparatus for configuring a low-power wireless mesh network composed of a channel-hopping time multiplexing wireless link according to an embodiment of the present invention includes a controller for setting a virtual link, a shared link, or a dedicated link with an external device or router; And
It includes a communication unit for forwarding the data frame to the device according to the established link or to the router.

Description

Routing device and method {ROUTING DEVICE AND METHOD}

The present invention relates to a routing apparatus and method. More specifically, it relates to a routing apparatus and method for a low power wireless network.

With the development of low-power wireless communication technology, it is possible to provide wireless communication functions to everyday devices, and the number of devices connected to the Internet is increasing.

Conventional low-power wireless communication technology aims to wirelessly connect devices at low cost, although communication reliability is low, such as one-time sensors and toys.

In recent years, it is required to construct a wireless network with high communication reliability and low power, such as industrial equipment and medical equipment. In particular, there is a need for an apparatus and method for configuring a wireless network with constant end-to-end transmission delay with low power.

Prior Document 1: Korean Patent Laid-Open Publication No. 10-2012-0100184 (Name of invention: Solar array monitoring system and method based on low-power sense network)

The problem to be solved by the present invention is to provide a low-power wireless communication network routing device and a routing method.

A routing apparatus for configuring a low-power wireless mesh network composed of a channel-hopping time multiplexing wireless link according to an embodiment of the present invention includes a controller for setting a virtual link, a shared link, or a dedicated link with an external device or router; And

It includes a communication unit for forwarding the data frame to the device according to the established link or to the router.

The virtual link, shared link, or dedicated link is composed of superframes having a beacon interval (BI) between a beacon and a beacon having a contention access period (CAP) and a guaranteed time slot (GTS), and BI One or more of my multi-superframes may be included.

When the virtual link is established, the control unit may perform relaying instead of forwarding a routed transmission frame.

The control unit may operate based on a link network sublayer (DLN) composed of a channel hopping time multiplexing link control sublayer (DLC) and a channel hopping time multiplexing link.

The control unit may perform link connection control, link management service, and data transmission on a link based on the DLC.

The control unit may configure the shared link and the dedicated link based on the DLC.

The DLN includes a link network formation block, an addressing block, a routing block, a link network management block, and a data processing block. I can.

The control unit is assigned an address from an upper router based on the DLN, and may select a routing path of the virtual link, shared link, or dedicated link.

A cluster unit for collecting cluster configuration information, intra-cluster mesh link information, and inter-cluster mesh link information between clusters and transmitting information to the control unit may be further included. .

The control unit may determine routing based on the intra-cluster mesh link information and the inter-cluster mesh link information.

A routing method for configuring a low-power wireless mesh network consisting of a channel hopping time multiplexing wireless link according to an embodiment of the present invention includes: setting a virtual link, a shared link, or a dedicated link with an external device or router by a controller; And a communication unit for forwarding a data frame to a device according to a link set by the communication unit or to a router.

The virtual link, shared link, or dedicated link is composed of superframes having a beacon interval (BI) between a beacon and a beacon having a contention access period (CAP) and a guaranteed time slot (GTS), and BI One or more of my multi-superframes may be included.

When the controller sets the virtual link, the controller may further include relaying the routed transmission frame instead of forwarding it.

The control unit may operate based on a link network sublayer (DLN) composed of a channel hopping time multiplexing link control sublayer (DLC) and a channel hopping time multiplexing link.

The control unit may perform link connection control, link management service, and data transmission on a link based on the DLC.

The control unit may configure the shared link and the dedicated link based on the DLC.

The DLN includes a link network formation block, an addressing block, a routing block, a link network management block, and a data processing block. I can.

The control unit may be assigned an address from an upper router based on the DLN, may set a routing path of the virtual link, and may set a routing path of the shared link and the dedicated link.

The cluster unit further comprises the step of collecting cluster configuration information, intra-cluster mesh link information, and inter-cluster mesh link information between clusters and transmitting to the control unit. I can.

The control unit may further include determining a routing based on the intra-cluster mesh link information and the inter-cluster mesh link information.

According to an embodiment of the present invention, an address system capable of providing networking at a link layer instead of an Internet protocol in a private wireless network not connected to the Internet by providing links of various qualities in a wireless network consisting of a channel hopping time multiplexing radio link , Provides a low-power routing device and method capable of configuring a low-power mesh network.

In addition, according to an embodiment of the present invention, a networking protocol such as Internet Protocol (IP) can be accommodated on a low-power wireless mesh network composed of a channel hopping time multiplexing wireless link, and if there is no network protocol, a link layer network protocol can be provided. Accordingly, it is possible to provide a highly reliable low-power wireless network based on a channel hopping time multiplexing wireless link.

1 is a diagram showing the topology of LPWMN.
2 is a block diagram of a router according to an embodiment of the present invention.
3 is a diagram showing a functional configuration diagram of an LPWMN according to an embodiment of the present invention.
4 is a diagram showing an LPWMN topology according to an embodiment of the present invention.
5 is a diagram illustrating a CAP link, a shared link, and a dedicated link in a low-power wireless mesh network according to an embodiment of the present invention.
6 is a diagram showing an embodiment of a shared link according to an embodiment of the present invention.
7 is a diagram showing an embodiment of a dedicated link according to an embodiment of the present invention.
8 is a diagram showing a cluster tree according to an embodiment of the present invention.
9 is a diagram illustrating a cluster tree based on mesh routing according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art may easily implement the present invention. However, the present invention may be implemented in various forms and is not limited to the embodiments described herein. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and similar reference numerals are assigned to similar parts throughout the specification.

Throughout the specification and claims, when a certain part "includes" a certain component, it means that other components may be further included rather than excluding other components unless otherwise stated.

In addition, throughout the specification, when a part is said to be "connected" with another part, this includes not only "directly connected" but also "electrically connected" with another element interposed therebetween. . When a part "includes" a certain component, it means that other components may be further included rather than excluding other components unless specifically stated to the contrary.

Now, a routing apparatus and method according to an embodiment of the present invention will be described in detail with reference to the drawings.

1 is a diagram showing the topology of LPWMN.

Low Power Wireless Mesh Network (LPWMN) is a reliable low cost communication network.

The low-power wireless network is constructed in consideration of the limitation of the transmission distance of the device and link instability due to changes in the wireless environment.

In addition, the low-power wireless network is configured in consideration of minimizing transmission/reception activation time for low-power operation and minimization of transmission/reception messages for configuring and maintaining a wireless network.

Through this, the low-power wireless mesh network is composed of a network that provides various quality classes that satisfy the limiting conditions during configuration.

Referring to FIG. 1, a low-power wireless mesh network includes one or more devices, one or more routers, and one or more gateway routers. However, the present invention is not limited thereto. Router, gateway router, and device operation are described in IEEE Std. 802.15. May be based on 4e-2012.

In addition, the low-power wireless mesh network may include a Deterministic and Synchronous Multi Channel Extension (DSME) MAC sublayer. The DSME MAC sublayer is IEEE Std. May be based on 802. 15. 4e-2012.

The gateway router starts the network by configuring the properties of the link network. In addition, the gateway router forms a link network topology and connects the wireless mesh network and the external network.

In addition, the gateway router uses IEEE 802.15.4-2011 and IEEE Std. 11 on the MAC (Media Access Control) sublayer. It can operate as a fan coordinator based on 802. 15. 4e-2012.

The router joins the link network. In addition, the router forwards the frame through the DSMC MAC link.

The router can operate as a coordinator.

The device may operate as a Reduced Function Device (RFD) or a Full Function Device (FFD). RFD or FFD is IEEE Std. 802.15.4-2011 and IEEE Std. May be based on 802. 15. 4e-2012. Also, the device performs an application.

Referring to FIG. 1, a low-power wireless mesh network operates in a star topology and a peer to peer topology.

Devices are typically connected to routers in a star topology. In addition, the device may be an initiation point or a termination point in link network communication.

The gateway router is the main controller in low-power wireless mesh networks. In addition, gateway routers and routers may constitute a peer-to-peer topology.

Link Network Addresses are assigned by cluster groups.

Next, an LPWMN according to an embodiment of the present invention will be described with reference to FIGS. 2 to 7.

2 is a block diagram of a router according to an embodiment of the present invention.

A router according to an embodiment of the present invention includes a communication unit 110, a control unit 120, and a cluster unit 130.

The communication unit 110 forwards data to other devices, routers, or other devices connected to the communication unit according to a link.

The controller 120 controls the overall operation of the router. The control unit 120 performs link control.

The cluster unit 130 configures a cluster tree and allocates cluster addresses. In addition, the cluster unit 130 configures mesh link information between devices in the cluster,

3 is a diagram showing a functional configuration diagram of an LPWMN according to an embodiment of the present invention.

The router according to the embodiment of the present invention operates based on the layer shown in FIG. 3.

The controller 120 of the router according to an embodiment of the present invention operates based on the next higher layer in the link control layer. In addition, the controller 120 according to an embodiment of the present invention provides a next higher layer or an application layer to a link network layer interface.

The operation of the control unit 120 according to an embodiment of the present invention operates on the IEEE Std 802.15.4e-2012 DSME MAC Sublayer and the IEEE Std 802.15.4-2011 Physical Layer (PHY).

The control unit 120 according to an embodiment of the present invention may operate based on two sublayers. The two sublayers that are the basis for the operation of the control unit 120 according to an embodiment of the present invention are a link network sublayer consisting of a channel hopping time multiplexing link control sublayer (DSME MAC Link Control sublayer, DLC) and a channel hopping time multiplexing link. It may include a layer (DSME MAC Link Network sublayer, DLN).

The DLCE (DSME MAC Link Control Sublayer Entity) provides a service to the next higher layer through a DSME MAC Link Control sublayer (DLC)-SAP (Service Access Point).

The DLNE (DSME MAC Link Network Sublayer Entity) provides services to the next higher layer through the DLN (DSME MAC Link Control sublayer)-SAP (Service Access Point).

Channel hopping time multiplexing link control (DSME MAC Link Control sublayer, DLC) provides link connection control, link management service, and data transmission on a link. The controller 120 performs link connection control, link management service, and data transmission on a link based on the DLC.

In addition, the DLC may relay a frame with support of the DSME MAC sublayer through a MAC Common Part Sublayer (MCPS)-SAP Service Access Point) and a MAC Layer Management Entity (MLME)-Service Access Point (SAP).

The DLN includes a link network formation block, an addressing block, a routing block, a link network management block, and a data processing block.

The data processing block provides a receiving function and a forwarding function for receiving a frame from a MAC layer or data from a next higher layer.

The controller 120 initializes a link of a router based on the DLN, configures a shared link of a channel hopping time multiplexing link in an upper layer having a network protocol, configures a dedicated link, and configures an It provides un-ack)-based frame delivery, ack-based frame delivery, and frame relaying on a dedicated link.

In addition, DLN maintains the status of beacon and channel hopping offset occupancy of peripheral devices of 1-hop inner router, beacon and channel hopping offset occupancy status of peripheral devices of 1-hop outer router, and beacon and channel hopping offset occupancy status of nearby devices. In addition, a beacon and channel hopping offset are selected for a router requesting a new join.

DLN provides a link layer network function to an upper layer without a network function.

Depending on the device configuration, the PAN coordinator initializes the low-power wireless mesh network based on the DLN and then manages network resources. In addition, the fan coordinator organizes a cluster according to a tree cluster structure and assigns addresses to routers.

The router control unit 120 collects neighboring network information based on the DLN, and receives an address and a beacon generation superframe and a channel hopping offset with the help of an inner router.

The router control unit 120 manages periodic cluster mesh link information, route information of a shared link, route information of a dedicated link, and maintains a routing table, It provides frame routing.

The controller 120 is assigned an address from an upper router based on the DLN and sets up a shared link. DLN provides three frame delivery methods to the upper layer: un-ack delivery, ack-based delivery, and path connection delivery.

4 is a diagram showing an LPWMN topology according to an embodiment of the present invention.

In addition, FIG. 4 shows a link shown in the network layer as a link layer multi-hop connection is provided in a low-power wireless mesh network based on a channel hopping time multiplexing link.

A low-power wireless mesh network according to an embodiment of the present invention includes one or more devices, one or more routers, a gateway router, and one or more link network routers. However, the present invention is not limited thereto, and can be applied even when a specific configuration is omitted. In FIG. 3, 8 devices (devices 1 to 8), 4 routers (routers 1 to 4), 2 network routers 2 to 3, and a gateway router are described as examples. However, the present invention is not limited thereto.

Routers connect devices and network routers. Also, a router connects the device to another router. Also, the router connects the device and the gateway router.

The controller 120 performs link control and transmits data to a device or a router for which a link is established through the communication unit 100. The controller 120 establishes a link between a router and a device connected to the router.

According to an embodiment of the present invention, the controller 120 may form a link as the virtual link, a shared link, or a dedicated link.

In an embodiment of the present invention, the virtual link may be a multi-hop link accessed through a relaying router instead of forwarding a routed transmission frame. .

In a channel hopping time multiplexed link-based low-power wireless mesh network, when a device initially forms a wireless link to join the network, one or more devices, routers, and network routers included in the wireless mesh network are inward for the wireless link. A shared link is configured by allocating two timeslots for tx (transmitter) and rx (receiver). Hereinafter, a router is described as an example, but the contents of the router described below can be applied to devices, link network routers, and gateway routers, except for the special description.

After the device joins the network, when requesting to configure a fixed path between a specific device and a device, the two devices are connected by a dedicated link in which the path is recognized as one link in the network layer.

In FIG. 4, when a dedicated link between network router 2 and device 6 is formed, router 2 and router 3 do not forward frames at the network layer, but relay frames at the link layer.

The control unit 120 of a router (router 2, router 3) located between network router 2 and device 6 does not forward the frame at the network layer, but relays the frame at the link layer.

That is, when a fixed path is formed between both devices with a router interposed between them, the control unit 120 of the route does not forward the frame at the network layer, but relays the frame at the link layer.

5 is a diagram illustrating a CAP link, a shared link, and a dedicated link in a low-power wireless mesh network according to an embodiment of the present invention.

The link formed by the controller 120 according to an embodiment of the present invention may be an IEEE 802.15.4e-2012 DSME MAC-based radio link.

The IEEE 802.15.4e-2012 DSME MAC-based radio link consists of superframes having a beacon interval (BI) of CAP and GTS between a beacon and a beacon, and one or more multi-superframes in the BI. Included.

CAP (Contention Access Period) is operated by CSMA-CA (Carrier Sense Multiple Access -Collision Avoidance).

In addition, CAP is used to transmit an outward MAC frame from a PAN coordinator to a device, or to transmit an inward MAC frame from a device to a PAN coordinator.

GTS (Guaranteed Time Slot) is allocated before use so that it can be used exclusively between two devices on a wireless link, and is allocated separately as inward tx or outward tx.

The controller 120 of the router can communicate with devices or routers in the same wireless area by using a plurality of wireless channels available in the timeslot.

The controller 120 of the router shares a channel hopping sequence to allocate a channel that does not overlap between devices or routers in the same area. The controller 120 of the router may differently allocate an offset of the start point of a hopping sequence between devices or routers.

In the inward link, the superframe structure of the PAN coordinator between the PAN coordinator and router 2 is composed based on router 2. Time slots are divided into inward rx slots and inward tx slots. Based on router 2, the outward link is formed based on the superframe structure of router 2 between router 2 and router 4. The timeslot is divided into an outward tx slot and an outward rx slot.

When a device joins a PAN coordinator as a router in a channel hopping time multiplexed link-based low-power wireless mesh network, the router controller 120 must select a superframe for generating a beacon of the router and a channel hopping offset without collision with other routers.

In addition, the router control unit 120 allocates the GTS so that there is no collision with neighboring devices for data frame delivery. The control unit 120 configures a routing path by selecting a radio link to be used for frame transmission from an arbitrary device to an arbitrary device.

6 is a diagram showing an embodiment of a shared link according to an embodiment of the present invention.

6 illustrates a shared link configuration and an outward shared link frame delivery path from a PAN coordinator to a device and an inward shared link frame delivery path from the device to the PAN coordinator along the shared link.

When a new device joins the network and connects to the router, the control unit 120 selects an adjacent router connected to the PAN coordinator by optimal routing, and establishes a shared link between the adjacent router and the joining device by using a predetermined time slot. Set. Therefore, a device or router joined to a router can have a path using a shared link to a PAN coordinator.

The default shared link is applied as an inward rx time slot used to transmit a frame from the inner coordinator to the device after the CAP of the superframe in which the beacon of the inner coordinator is transmitted is finished when the device joins the network in an embodiment. do

Also, the second time slot is applied as an inward tx time slot used to transmit a frame from the device to the inner coordinator. The frame received in the tx timeslot of the outward shared link of the PAN coordinator is transmitted in the tx timeslot of the outward shared link of router 1.

Referring to FIG. 6, a frame transmitted in the inward shared link tx timeslot of the device is received in the rx timeslot of the outward shared link of router 2 and transmitted in the tx timeslot of the inward shared link of router 2. For the path by the outward shared link and the forward path by the inward shared link, a fixed value delivery delay is determined according to the number of router layers and the location of the router beacon transmission.

7 is a diagram showing an embodiment of a dedicated link according to an embodiment of the present invention.

7 shows a dedicated link connection through router 1 and router 2 between a PAN coordinator and a device.

The control unit 120 configures a dedicated link using a time slot exclusively allocated for transferring a frame between a specific device and a device.

For a dedicated link, the link source device designates the destination device, and configuration starts from the source device. The source device selects an adjacent device connected to the destination device according to routing information and sets a timeslot for the inward link, and then selects the next router according to the routing information of the adjacent device and sets the timeslot for the inward link.

When the inward path to the destination device is established in this way, the outward dedicated link is established to the source device by setting the time slot for the outward link for each router by crossing the router in the reverse direction from the destination device. Timeslot selection for inward dedicated link and timeslot for outward dedicated link utilizes the time slot resources in the network to the maximum and allocates to minimize inward and outward end-to-end delay.

As an example, as shown in FIG. 7, time slots of a dedicated multi-hop link may be sequentially allocated to timeslots within one superframe. Dedicated link is used after setting the link layer before data frame delivery.

8 is a diagram showing a cluster tree according to an embodiment of the present invention.

9 is a diagram illustrating a cluster tree based on mesh routing according to an embodiment of the present invention.

8 and 9, routers and devices in a low-power wireless mesh network based on a channel hopping time multiplexing link are connected in a cluster tree form.

The cluster unit 130 of the router allocates an address using the cluster ID, the location in the tree, the maximum depth (Lm), the maximum number of children (Cm), and the number of routers (Rm).

The cluster unit 130 collects cluster configuration information, intra-cluster mesh link information between trees within the cluster, and inter-cluster mesh link information between clusters. The cluster unit 130 transmits the collected information as routing information to the control unit 120.

In frame routing using a dedicated link or a shared link, the control unit 120 determines routing based on routing information.

The control unit 120 determines the routing using the path distance using the cluster mesh link and the reliability and load information of the link.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention defined in the following claims are also present. It belongs to the scope of rights of

110: communication unit 120: control unit
130: cluster unit

Claims (20)

In the routing device for configuring a low-power wireless mesh network composed of a channel hopping time multiplexed wireless link,
A control unit for setting a shared link with an external device using the in-word rx timeslot and the in-word tx timeslot, and setting a dedicated link including an inward dedicated link and an outward dedicated link; And
Includes a communication unit for forwarding a data frame to the external device according to the set link,
The shared link and the dedicated link are composed of superframes having a beacon interval (BI) having a contention access period (CAP), a guaranteed time slot (GTS), and a multi-superframe,
The routing device is addressed using a cluster tree,
The cluster tree corresponds to a cluster ID, and the routing device is addressed using a location in the cluster tree,
The control unit sets a virtual link to the set link,
The virtual link corresponds to a multi-hop link connected through a relaying router instead of forwarding a routed transmission frame. delete The method of claim 1,
The dedicated link is a routing device corresponding to relaying instead of forwarding for a routed transmission frame. The method of claim 1,
The control unit operates based on a link network sublayer (DLN) comprising a channel hopping time multiplexing link control sublayer (DLC) and a channel hopping time multiplexing link. According to claim 4
The control unit is a routing device for performing link connection control, link management service, and data transmission on a link based on the DLC. The method of claim 5,
The control unit is a routing device that configures the shared link and the dedicated link based on the DLC. The method of claim 4,
The DLN includes a link network formation block, an addressing block, a routing block, a link network management block, and a data processing block. Routing device. The method of claim 7,
The control unit receives an address from an upper router based on the DLN, and selects a routing path of the virtual link, a shared link, or a dedicated link. delete delete In the routing method for configuring a low-power wireless mesh network consisting of a channel hopping time multiplexed wireless link,
Establishing a shared link with an external device using an in-word rx timeslot and an in-word tx timeslot, and establishing a dedicated link including an inward dedicated link and an outward dedicated link; And
Including the step of forwarding the data frame to the external device according to the set link,
The shared link and the dedicated link are composed of superframes having a beacon interval (BI) having a contention access period (CAP), a guaranteed time slot (GTS), and a multi-superframe,
The routing device is addressed using a cluster tree,
The cluster tree corresponds to a cluster ID, and the routing device is addressed using a location in the cluster tree,
The setting step sets up a virtual link with the set link,
The virtual link corresponds to a multi-hop link accessed through a relaying router instead of forwarding the routed transmission frame.
Routing method. delete The method of claim 11,
The dedicated link is a routing method corresponding to relaying instead of forwarding for a routed transmission frame. The method of claim 11,
The setting step is performed based on a link network sublayer (DLN) comprising a channel hopping time multiplexing link control sublayer (DLC) and a channel hopping time multiplexing link. The method of claim 14
The channel hopping time multiplexing link control sublayer (DLC) is a routing method for providing link connection control, link management service, and data transmission on a link. The method of claim 15,
The setting step is a routing method of configuring the shared link and the dedicated link based on the channel hopping time multiplexing link control sublayer. The method of claim 14,
The DLN includes a link network formation block, an addressing block, a routing block, a link network management block, and a data processing block. Routing method. The method of claim 17,
In the setting step, an address is allocated from an upper router based on the DLN, and a routing path for the shared link and the dedicated link is set. delete delete

Images