KR101581127B1 - Network system and communication method and network device - Google Patents

Abstract

Provided is a network system, a communications method and a network device. Provided may be the network system comprising: a network control layer including a plurality of heterogeneous software type controllers controlling a plurality of communications devices; and a multi controller interface (MCI) layer providing a unified interface between the network control layer and an application layer, which is an upper layer of the network control layer.

Description

TECHNICAL FIELD [0001] The present invention relates to a network system,

A network system, a communication method, and a network apparatus are disclosed.

When developing an application in a software defined networking (SDN) environment, the application can be developed for a specific purpose by utilizing the NorthBound interface exposed by the SDN controller.

While the industry standard OpenFlow is defined between the SDN controller and the SDN switch equipment, the interface between the SDN controller and the SDN application has not been set to an industry standard. That is, there are various interfaces for developing applications for each SDN controller vendor or OSS (Open Source Software). As a result, the dependency of a specific solution can not be avoided in developing an SDN application, and development productivity and operational efficiency may also be degraded.

In addition, Network Function Virtualization (NFV), which provides virtualization capabilities through the abstraction of hardware resources, provides an external interface through the NFV Orchestrator. Network Functional Virtualization (NFV) Like software defined networking (SDN), industry standards have not been set.

According to one embodiment, it is possible to provide a single point of contact for applications through the integration of interfaces in software defined networking (SDN) and network functional virtualization (NFV) network environments.

According to one embodiment, a network system comprises: a network control layer including a plurality of heterogeneous controllers in software form for controlling a plurality of communication devices; And a Multi Controller Interface (MCI) layer that provides an integrated interface between the network control layer and an application layer that is an upper layer of the network control layer.

The network system may be based on at least one network environment, such as software-defined networking (SDN) and network function virtualization (NFV).

Wherein the integrated interface comprises an interface provided by the heterogeneous controllers for the software defined networking (SDN) to the application layer and an interface provided by the orchestrator for the network functional virtualization (NFV) May be abstracted and integrated.

The plurality of disparate controllers may include controllers for software defined networking (SDN) and managers for network functional virtualization (NFV).

The MCI layer includes a first module for performing integration and interworking with services provided in a general network environment, a second module for managing at least one controller connected to the multiple control interface layer, A third module for abstracting the different interfaces for the same purpose provided by each of the plurality of heterogeneous controllers into one integrated interface, a third module for normalizing the abstracted abstract interface in the third module, 4 modules, at least one of a seventh module including a fifth module for cluster data management and a sixth module for managing sessions of the application layer, or a memory-based DBMS (Data Base Management System) . ≪ / RTI >

Wherein the multiple control interface layer communicates with the application layer by conveying a message through the unified interface, the message including an identifier indicating a result of a call to the multiple control interface layer, At least one of the identification information of the controller providing the requested information, the identification information of the cluster managed by the controller providing information requested by the application layer, or the result value requested by the application layer through the call to the multiple control interface layer . ≪ / RTI >

The identifier indicating the result of the call to the multiple control interface layer includes a first code indicating that the call to the multiple control interface layer has succeeded, a second code indicating that the call succeeded but no request content, and an unauthorized request A fourth code indicating that there is no interface requested through the multiple control interface layer, or a fifth code indicating an error occurrence in the multiple control interface layer.

According to one embodiment, a communication method includes: receiving a communication request from a plurality of heterogeneous controllers for a network control layer with an application layer that is an upper layer of the network control layer; And providing an integrated interface for communication between the network control layer and the application layer through a multi controller interface (MCI) layer in response to the request.

The communication may be based on at least one network environment, such as software-defined networking (SDN) and network function virtualization (NFV).

Wherein the integrated interface comprises an interface provided by the heterogeneous controllers for the software defined networking (SDN) to the application layer and an interface provided by the orchestrator for the network functional virtualization (NFV) May be abstracted and integrated.

The plurality of disparate controllers may include controllers for software defined networking (SDN) and managers for network functional virtualization (NFV).

The MCI layer includes a first module for performing integration and interworking with services provided in a general network environment, a second module for managing at least one controller connected to the multiple control interface layer, A third module for abstracting the different interfaces for the same purpose provided by each of the plurality of heterogeneous controllers into one integrated interface, a third module for normalizing the abstracted abstract interface in the third module, 4 modules, at least one of a seventh module including a fifth module for cluster data management and a sixth module for managing sessions of the application layer, or a memory-based DBMS (Data Base Management System) . ≪ / RTI >

Transmitting a message for communication with the application layer to the plurality of heterogeneous controllers through the multi-control interface (MCI) layer, the message including a message indicating a result of the call to the multiple control interface layer An identification of the controller that provides information requested by the application layer, identification information of a cluster managed by the controller that provides information requested by the application layer, or a call to the multiple control interface layer And may include at least one of the result values requested by the application layer.

The identifier indicating the result of the call to the multiple control interface layer includes a first code indicating that the call to the multiple control interface layer has succeeded, a second code indicating that the call succeeded but no request content, and an unauthorized request A fourth code indicating that there is no interface requested through the multiple control interface layer, or a fifth code indicating an error occurrence in the multiple control interface layer.

According to one embodiment, the network device comprises: a memory for storing a program for controlling the operation of the network device; And at least one processor for driving the program, wherein the plurality of heterogeneous controllers for a network control layer comprise at least one of a network control layer and an application layer (MCI) layer that provides an integrated interface between the application layer and the application layer.

According to one aspect of the present invention there is provided a method for providing a network interface between a plurality of heterogeneous SDN controllers in a Software Defined Networking (SDN) and Network Functional Virtualization (NFV) network environment, the NorthBound Interface and the NFV Orchestrator interface Integration provides a single point of contact for the application, providing development enhancement and operational efficiency.

According to one aspect of the present invention, a multi-controller interface (MCI) layer can perform management of the SDN controller and the NFV orchestrator instead so that the application concentrates only on its own functions.

1 is a block diagram illustrating a network system including a Multi Controller Interface (MCI) layer according to an exemplary embodiment of the present invention.
2 is a diagram illustrating a case where an SDN application requests network topology information to one SDN controller in a software-defined networking (SDN) environment.
3 is a diagram illustrating a case where an SDN application requests network topology information to a plurality of SDN controllers in a software defined networking environment.
4 is a diagram illustrating a method for providing a single point of contact to an SDN application through a multiple control interface (MCI) layer according to one embodiment.
FIG. 5 is a diagram illustrating components of a multiple control interface (MCI) layer according to one embodiment.
6 is a diagram illustrating a data structure provided by a multiple control interface (MCI) layer according to an exemplary embodiment of the present invention.
7 is a flowchart illustrating a communication method according to an embodiment.
8 is a block diagram of a network device in accordance with one embodiment.

In the following, embodiments will be described in detail with reference to the accompanying drawings. Like reference symbols in the drawings denote like elements.

Various modifications may be made to the embodiments described below. It is to be understood that the embodiments described below are not intended to limit the embodiments, but include all modifications, equivalents, and alternatives to them.

The terms used in the examples are used only to illustrate specific embodiments and are not intended to limit the embodiments. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms "comprises" or "having" and the like refer to the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this embodiment belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

In the following description of the present invention with reference to the accompanying drawings, the same components are denoted by the same reference numerals regardless of the reference numerals, and redundant explanations thereof will be omitted. In the following description of the embodiments, a detailed description of related arts will be omitted if it is determined that the gist of the embodiments may be unnecessarily blurred.

1 is a block diagram illustrating a network system including a Multi Controller Interface (MCI) layer according to an exemplary embodiment of the present invention.

In one embodiment, the network environment can be understood as a network environment including Software Defined Networking (SDN) and Network Function Virtualization (NFV).

In the following, software defined networking (SDN) and network function virtualization (NFV) will be described before describing the Multi Controller Interface (MCI) layer.

Software-defined networking (SDN) is a next-generation network technology that represents the entire technology, industrial structure, and ecosystem composition of the network industry structure, which has been discussed under the dependent protocol of equipment operators, into a software-based open standard protocol.

In software defined networking (SDN), the controller is softwareed to determine the path and policy, and the switch can perform packet forwarding based on the policy received from the controller. The communication protocol used between the controller and the switch is the OpenFlow protocol. The specification of the OpenFlow protocol defines the message conventions between the controller and the switch.

The OpenFlow protocol may be referred to as the SouthBound Interface (SBI) in terms of the entire layer of software defined networking (SDN). Since the south bound interface (SBI) area is standardized with a protocol called OpenFlow, the SDN controller can manage and control devices without vendor dependency on the underlying devices.

The NorthBound Interface (NBI) is understood as an interface that the SDN controller provides to high-end applications. In the northbound interface (NBI) area, there is no standardization yet, and SDN controller vendors define their own interfaces.

From the standpoint of SDN applications that need to be developed using the SDN controller's northbound interface (NBI), dependencies on certain controllers can not be avoided. Also, if a new controller is added, or a northbound interface (NBI) is updated, the application may have to be redeveloped for each northbound interface (NBI). If the application is redeveloped for each North-Bound Interface (NBI), the development productivity and operational efficiency of the application may also be compromised.

Network Functional Virtualization (NFV) is a technology that enables programmable management of hardware resources that make up a network, such as servers and storage.

As network functional virtualization (NFV) technology enables programming of hardware resources, it can simplify complex networks while performing network functions with a general-purpose server. The simplification of the network means a physical reduction of the operating hardware and can lower the equipment cost. In addition, simplification of the network ultimately enables the rapid response according to the user environment and the service demand through the enhancement of the service by the flexible network connection and expansion.

Network Functional Virtualization (NFV) can implement the above functions through software through the Orchestrator Interface, but the standardization of this part has not been done yet.

Referring to Figure 1, a network system in a network environment based on Software Defined Networking (SDN) and Network Functional Virtualization (NFV) is illustrated.

The network system according to one embodiment includes an infrastructure layer 110, a network control layer 120, a multi-controller interface (MCI) layer 130, (Application Layer) 140.

The Infrastructure Layer 110 may include SDN devices such as switches, router equipment, etc., hardware resources such as servers and storage programmed in Network Functional Virtualization (NFV) ), And network elements of an existing network (Legacy Network).

The network control layer 120 may include a plurality of heterogeneous controllers in software that control a plurality of communication devices in hardware or software form contained in the infrastructure layer 110.

The network control layer 120 may include a plurality of heterogeneous controllers in software that control a plurality of communication devices. A number of heterogeneous controllers may include controllers for software defined networking (SDN) and managers for network functional virtualization (NFV).

The controllers for software defined networking (SDN) may include commercial SDN controllers and open source SDN controllers.

A multi-controller interface (MCI) layer 130 may provide an integrated interface between the network control layer 120 and the application layer 140.

Here, the unified interface includes an interface that each of the heterogeneous controllers for software defined networking (SDN) provides to the application layer 140 and an orchestrator for network functional virtualization (NFV) The interface may be abstract and integrated.

The MCI layer 130 provides a single interface for the application layer 140 to the Orchestrator Interface of the NBI and NFV between the multiple heterogeneous SDN controllers. Can be provided.

The application layer 140 may include applications developed using a unified application program interface (API) provided by a multiple control interface layer (MCI Layer) 130.

2 and 3 below, a case where an SDN application requests network topology information to one controller or a plurality of SDN controllers in a software defined networking (SDN) environment will be described. In addition, FIG. 4 illustrates a case where an SDN application requests network topology information through a multiple control interface (MCI) layer according to an embodiment.

2 is a diagram illustrating a case where an SDN application (SDN Application) in a software defined networking (SDN) environment utilizes a NorthBound interface of one controller.

Referring to FIG. 2, a case where an SDN application requests network topology information to an SDN controller (SDN controller) is shown.

SDN applications can request network topology information using the SDN controller's NorthBound interface. At this time, the SDN application needs to call the application program interface (API) provided by the corresponding SDN controller, that is, the north bound interface AA to receive the network topology information. AA may be, for example, "/realnetwork/topologies/detail.xml".

3 is a diagram illustrating a case where an SDN application requests network topology information from a plurality of SDN controllers in a software defined networking (SDN) environment.

Referring to FIG. 3, an SDN application requests network topology information to SDN controllers (for example, SDN controller 1 and SDN controller 2) included in a network control layer.

At this time, the name of the north bound interface for providing the network topology information differs for each SDN controller.

The name of the northbound interface of the SDN controller 1 for providing network topology information is AA, and the name of the northbound interface of the SDN controller 2 may be AB.

AA may be, for example, "/realnetwork/topologies/detail.xml" and AB may be, for example, "/ controller / nb / v2 / topology / {containerName} (SDN controller 2)".

Because the name of the northbound interface is different for each SDN controller, an SDN application utilizing the network topology information must call the northbound interface of each of the SDN controllers.

In FIG. 3, the case where the northbound interface provided by the different SDN controllers is the same interface based on the Web service has been described as an example.

If the SDN controller's northbound interface scheme is different from each other, for example, JMS (Java Message Service), Jar type, or if the Uniform Resource Locator (URL) invoked by the northbound interface is updated, A more complex process is required.

4 is a diagram illustrating a method for providing a single connection to an SDN application through a multiple control interface (MCI) layer according to an embodiment.

Referring to FIG. 4, a multi-control interface (MCI) layer according to an exemplary embodiment provides a single point of contact to an SDN application, while SDN controllers included in a network control layer (for example, an SDN controller 1 and the SDN controller 2).

The Multiple Control Interface (MCI) layer can, for example, use an NBI converter to integrate the different northbound interfaces between the SDN controllers into one to provide a single point of contact to the SDN application.

The integrated northbound interface provided by the multiple control interface (MCI) layer may be, for example, "lgcns / MCI / AA ".

In addition, the multiple control interface (MCI) layer can manage the SDN controller 1 and the SDN controller 2 connected to the multiple control interface (MCI) layer by, for example, a controller management module (Controller Mgt). The multiple control interface (MCI) layer can perform connection management and authentication management for the SDN controller 1 and the SDN controller 2.

As shown in FIG. 4, the SDN application can receive the information through the integrated interface ("lgcns / MCI / AA") regardless of the type of the SDN controller in utilizing the network topology information.

By providing information through the integrated interface provided by the multiple control interface (MCI) layer, the SDN application does not need to develop additional applications even when the SDN controller interface method is changed or the interface name is changed.

This allows the SDN application to increase the development productivity and operational efficiency of the application without any dependency on the SDN controller.

4 can be equally applied to managers for network function virtualization (NFV) as well as SDN controllers.

FIG. 5 is a diagram illustrating components of a multiple control interface (MCI) layer according to one embodiment.

5, the multiple control interface (MCI) layer 500 includes a service orchestration module 510, a controller management module 520, a SB (South Bound) interface module 530, a common interface module 540, a cluster management module 550, a session management module 560, and an in memory DB (In Memory DB) 570 And may include at least one.

The service orchestration module 510 can perform integration and interworking of services provided in a general current network environment.

The controller management module 520 may manage at least one controller coupled to a multiple control interface (MCI) layer. The controller management module 520 may perform connection management and authentication management for at least one controller connected to the multiple control interface (MCI) layer.

The SB Interface module 530 may abstract different interfaces for the same purpose provided by each of the plurality of heterogeneous controllers into one integrated interface. Here, the plurality of heterogeneous controllers may include controllers for software defined networking (SDN) and managers for network functional virtualization (NFV).

The common interface module 540 may normalize the abstract interface abstracted by the SB interface module 530 and provide the application interface as an application layer.

The cluster management module 550 can manage and manage the interface data by clustering for processing of large-capacity data.

The Session Management module 560 may manage the session of the application layer. The Session Management module 560 can manage the access of the SDN controller and the Orchestrator for Network Functional Virtualization (NFV) through the session management of the application layer.

The in-memory DB (In Memory DB) 570 may include a memory-based DBMS (Data Base Management System). The in-memory DB (In Memory DB) 570 is a memory-based DBMS, unlike a disk-based DBMS, and is suitable for a network environment in which the real-time accessibility of data is excellent and a quick response is required.

6 is a diagram illustrating a data structure provided by a multiple control interface (MCI) layer according to an exemplary embodiment of the present invention.

6, a message that an application application receives from a multiple control interface (MCI) layer may include at least one of Result_Code 610, Destination_ID 620, Cluster ID 630, and Result_Set 640.

Result_Code 610 is an identifier indicating the result of the call to the multiple control interface (MCI) layer. For example, if Result_Code (610) is the first code, it indicates that the call to the multiple control interface (MCI) layer has succeeded; if the second code, the call to the multiple control interface No content can be indicated. For example, the first code may be '00' and the second code may be '01'.

If the Result_Code 610 is the third code, it indicates that the call to the multiple control interface layer is an unauthorized request, and if it is the fourth code, it indicates that the interface requested through the multiple control interface layer does not exist . In addition, if the Result_Code (610) is the fifth code, it may indicate an error occurrence in the multiple control interface (MCI) layer. For example, the third code may be '02', the fourth code may be '03', and the fifth code may be '04'.

The Destination_ID 620 may indicate identification information (e.g., ID) of a controller or MANO (Management & Orchestration) that provides information requested by an application layer among a plurality of heterogeneous controllers.

The Cluster_ID 630 may indicate the identification information of the cluster managed by the controller providing the information requested by the application layer.

The Result_Set 640 may indicate a result value requested by the application layer through a call to the multiple control interface (MCI) layer. Result_Set 640 may be, for example, in the form of xml or json.

7 is a flowchart illustrating a communication method according to an embodiment.

Referring to FIG. 7, a method of communication in a network environment based on software defined networking (SDN) and network functional virtualization (NFV) is illustrated.

The multiple control interface (MCI) layer according to an exemplary embodiment may receive 710 a communication request from a plurality of heterogeneous controllers for a network control layer to an application layer that is an upper layer of the network control layer. At this time, the plurality of heterogeneous controllers may include controllers for software defined networking (SDN) and managers for network functional virtualization (NFV).

The multiple control interface (MCI) layer may provide 720 an integrated interface for communication between the network control layer and the application layer to a plurality of heterogeneous controllers in response to the request of step 710.

Here, the integrated interface includes an interface provided by the heterogeneous controllers for software defined networking (SDN) to the application layer and an interface provided by the orchestrator for network function virtualization (NFV) to the application layer, Lt; / RTI >

The Multiple Control Interface (MCI) layer may send a message to the plurality of disparate controllers for communication with the application layer (730). At this time, the message may have a data structure as shown in FIG. 6, and a description thereof will be made with reference to the corresponding portion of FIG.

8 is a block diagram of a network device in accordance with one embodiment.

Referring to FIG. 8, a network device 800 according to an embodiment may include a memory 810, a processor 830, and a communication unit 850.

The memory 810 can record a program that controls the operation of the network device 800. [

One or more of the processors 830 may be included, and the programs stored in the memory 810 may be driven.

At this time, the program stored in the memory 810 is transmitted to the application layer through a multi-control interface layer that provides an integrated interface between the network control layer and the application layer, which is an upper layer of the network control layer, And the like.

The communication unit 850 can exchange data with the network control layer or the multiple control interface layer under the control of the processor 830.

The method according to an embodiment of the present invention can be implemented in the form of a program command which can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions recorded on the medium may be those specially designed and configured for the present invention or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. This is possible.

Therefore, the scope of the present invention should not be construed as being limited to the embodiments described, but should be determined by equivalents to the appended claims, as well as the following claims.

810: Memory
830: Processor
850:

Claims (16)

In a network system,
A network control layer including a plurality of heterogeneous controllers in the form of software for controlling a plurality of communication devices; And
A Multi Controller Interface (MCI) layer providing an integrated interface between the network control layer and an application layer that is an upper layer of the network control layer,
/ RTI >
Wherein the multiple control interface layer comprises:
Wherein the application layer provides an integrated interface in which different interfaces for the same purpose provided by the plurality of heterogeneous controllers are abstracted. The method according to claim 1,
The network system includes:
Wherein the network system is based on at least one network environment of software-defined networking (SDN) and network function virtualization (NFV). 3. The method of claim 2,
The integrated interface comprises:
An interface provided by the heterogeneous controllers for the software defined networking (SDN) to the application layer and an interface provided by the orchestrator for the network functional virtualization (NFV) to the application layer are abstracted and integrated Network system. The method according to claim 1,
The plurality of heterogeneous controllers
A controller for software defined networking (SDN), and a manager for network functional virtualization (NFV). The method according to claim 1,
The multi-control interface (MCI)
A first module for performing integration and interworking with services provided in a general network environment, a second module for managing at least one controller connected to the multiple control interface layer, and a second module for managing the same A fourth module for normalizing the abstracted abstract interface in the third module and providing the integrated interface to the application layer, a second module for abstracting the interface data A sixth module for managing a session of the application layer, or a seventh module including a memory-based DBMS (DataBase Management System). The method according to claim 1,
Wherein the multiple control interface layer comprises:
Communicating with the application layer by passing a message over the unified interface,
The message comprises:
An identifier indicating a result of a call to the multiple control interface layer, identification information of a controller providing information requested by the application layer among the plurality of heterogeneous controllers, identification of a cluster managed by a controller providing information requested by the application layer Information, or a result value requested by the application layer through a call to the multiple control interface layer. The method according to claim 6,
The identifier indicating the result of the call to the multiple control interface layer,
A first code indicating success in a call to the multiple control interface layer, a second code indicating that the call succeeded but no request content, a third code indicating a request not being granted, Or a fifth code indicating an error occurrence within the multiple control interface layer. ≪ Desc / Clms Page number 13 > In a communication method,
Receiving a communication request from a plurality of heterogeneous controllers for a network control layer with an application layer that is an upper layer of the network control layer; And
Providing an integrated interface for communication between the network control layer and the application layer through a multi controller interface (MCI) layer in response to the request;
Lt; / RTI >
Wherein the multiple control interface layer comprises:
Wherein the application layer provides an integrated interface in which different interfaces for the same purpose provided by the plurality of heterogeneous controllers are abstracted. 9. The method of claim 8,
The communication includes:
Wherein the at least one network environment is based on at least one of software-defined networking (SDN) and network function virtualization (NFV). 10. The method of claim 9,
The integrated interface comprises:
An interface provided by the heterogeneous controllers for the software defined networking (SDN) to the application layer and an interface provided by the orchestrator for the network functional virtualization (NFV) to the application layer are abstracted and integrated / RTI > 9. The method of claim 8,
The plurality of heterogeneous controllers
Controllers for software defined networking (SDN), and managers for network functional virtualization (NFV). 9. The method of claim 8,
The multi-control interface (MCI)
A first module for performing integration and interworking with services provided in a general network environment, a second module for managing at least one controller connected to the multiple control interface layer, and a second module for managing the same A fourth module for normalizing the abstracted abstract interface in the third module and providing the integrated interface to the application layer, a second module for abstracting the interface data And a seventh module including a fifth module for managing the session of the application layer, a sixth module for managing sessions of the application layer, or a memory based DBMS (DataBase Management System). 9. The method of claim 8,
Transmitting a message for communication with the application layer to the plurality of heterogeneous controllers through the multiple control interface (MCI) layer
Lt; / RTI >
The message comprises:
(ID) of a controller that provides information requested by the application layer among the plurality of heterogeneous controllers, a controller that provides information requested by the application layer, and an identifier The identification information of the cluster, or the result value requested by the application layer through a call to the multiple control interface layer. 14. The method of claim 13,
The identifier indicating the result of the call to the multiple control interface layer,
A first code indicating success in a call to the multiple control interface layer, a second code indicating that the call succeeded but no request content, a third code indicating a request not being granted, Or a fifth code indicating an error occurrence within the multiple control interface layer. ≪ Desc / Clms Page number 12 > A computer-readable recording medium having recorded thereon a program for performing the method according to any one of claims 8 to 14. In a network device,
A memory for storing a program for controlling an operation of the network device; And
One or more processors for running the program
Lt; / RTI >
The program includes:
A plurality of heterogeneous controllers for a network control layer include a Multi Controller Interface (MCI) that provides an integrated interface between the network control layer and an application layer that is an upper layer of the network control layer, Layer, to communicate with the application layer,
Wherein the multiple control interface layer comprises:
Wherein the application layer provides an integrated interface in which different interfaces for the same purpose provided by the plurality of heterogeneous controllers are abstracted.

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