KR102485601B1 - Method of selecting optimal network node for contents delivery service and apparatus therefor - Google Patents

Abstract

In the present invention, in providing an MMT-based content transmission service, state information is collected from a plurality of network nodes that transmit MMT-based content data, respectively, and the collected state information is based on the collected state information in a client device that requests content transmission. It relates to a method for selecting an optimal network node for content transmission and an apparatus therefor, which can provide path information for an optimal network node, and a plurality of network nodes and clients that cache and transmit content based on the MMT protocol. A content delivery network (CDN) management device that works with the device receives and stores a state information message including state information of each network node from a plurality of network nodes, and when content transmission is requested from the client device, the state information After selecting a network node to transmit content from among a plurality of network nodes based on, the network node notification message including information on the selected network node is transmitted to the client device.

Description

Method of selecting optimal network node for contents delivery service and apparatus therefor}

In the present invention, in providing an MMT-based content transmission service, state information is collected from a plurality of network nodes that transmit MMT-based content data, respectively, and the collected state information is based on the collected state information in a client device that requests content transmission. It relates to a method for selecting an optimal network node for content transmission and an apparatus therefor to provide path information for an optimal network node.

Recently, with the development of broadcasting and communication technology, the demand for high-quality and large-capacity video services is increasing due to the enlargement of displays and the development of UHD (Ultra high definition) video technology. Research is being conducted on heterogeneous network services, including not only broadcasting networks but also communication networks.

Currently, terrestrial broadcasting uses MPEG-2 TS as a transmission format to transmit video, audio, metadata, etc., and when it is transmitted over a communication network, a form of TS over IP packet is required to enable mutual conversion with IP, so an additional IP header , it increases complexity and is inefficient in terms of payload ratio.

Accordingly, MMT (MPEG Media Transport), an IP-based next-generation media transport standard technology that is not limited by transport networks and terminals, has been standardized. Since MMT has an IP-based format structure, it does not require additional work when transmitting over a communication network, and is known to be more flexible and efficient in an environment where one content is layer-coded and serviced through heterogeneous networks.

On the other hand, as content transmission traffic increases rapidly with the improvement of user terminal performance such as smart phones and the development of mobile communication technology, the quality problem of content transmission service becomes more important, and as a technology to solve this problem, , CDN (Contents Delivery Network) service is being used.

The CDN service is a service for stably delivering various types of content such as photos, movies, music videos, etc. to the user's terminal. Some or all of the frequently requested contents are copied and stored in advance in cache servers distributed on the network, and then, when there is a user's content request, the cache server is selected according to the distance from the user or the server load. By returning the path, it means a service that allows the user's terminal to access the corresponding cache server through the returned path and then receive content.

However, in the MMT technology, a technology for applying such a CDN service is not considered, and in particular, a technology for load balancing processing of MMT-based media servers is not considered.

Korean Registered Patent No. 1039370, registered on May 31, 2011 (Name: GSLB server by domain delegation and CDN service system and method using it)

In the present invention, in providing an MMT-based content transmission service, state information is collected from a plurality of network nodes that transmit MMT-based content data, respectively, and the collected state information is based on the collected state information in a client device that requests content transmission. It is intended to provide a method for selecting an optimal network node for content transmission and an apparatus therefor, which can provide path information for an optimal network node.

As a means to solve the above problems, the present invention provides content transmission of a CDN (Contents Delivery network) management device that works with a plurality of network nodes and client devices that cache and transmit content based on the MMT (MPEG Media Transport) protocol. A method for selecting an optimal network node for a CDN management device, comprising: receiving and storing, by the CDN management device, a state information message including state information of each network node from a plurality of network nodes; selecting a network node to transmit content from among a plurality of network nodes based on the state information when content transmission is requested from the client device; and transmitting to the client device through a network node notification message including information on the selected network node.

Here, the status information message includes the IP address (MANE_IP) of the network node, the operation mode (MANE_mode) of the network node, current session information (Current session), maximum session capacity (Max session capacity), response time (Response time), CPU may include one or more of load (CPU_load), GPU load (GPU_load), memory usage (RAM_usage), virtualization flag indicating whether the network node is a temporarily created virtual network node (Virtual_flag), and measurement time (Measure_time); If the network node is a virtual network node, it may further include a valid start time (valid_time_start) indicating a creation time of the virtual network node and a valid period (valid_time_duration) indicating a maintenance time of the virtual network node.

In addition, the network node notification message may include one or more of address information (source URL), PA (Package Access) information, package ID (Package ID), and asset ID (asset ID) of the selected network node 100. .

And, in the step of selecting, the IP address (MANE_IP) of the network node, the operation mode (MANE_mode) of the network node, current session information (Current session), maximum session capacity (Max session capacity), response time (Response time) , CPU load (CPU_loas), GPU load (GPU_load), memory usage (RAM_usage), virtualization flag indicating whether the network node is a temporary virtual network node (Virtual_flag), valid start time (valid_time_start), valid period (valid_time_duration) It is possible to select a network node to transmit the content according to a load index of each network node calculated by combining one or more of , , and measurement time (Measure_time).

The optimal network node selection method for content transmission according to the present invention may be implemented as a program and stored in a computer-readable recording medium.

As another solution to the above-described problem, a state information DB for storing state information of a plurality of network nodes performing content caching and transmission based on the MMT protocol; a status information collection module configured to collect status information by receiving status report messages transmitted from the plurality of network nodes; and when content transmission is requested from the client device, selects a network node to transmit the content from among a plurality of network nodes based on the status information, and transmits a network node notification message including information about the selected network node to the client device. Provides a CDN management device including a control module for transmitting.

The present invention collects status information of a plurality of network nodes that cache and transmit contents according to the MMT protocol through a status report message, and selects a network node to transmit contents to a client device based on the status information collected in this way. By transmitting information to a client device through a network node notification message, load balancing of a plurality of network nodes is possible in an MMT-based content delivery service.

In addition, through this, there is an effect of further improving the service quality of the MMT-based content transmission service.

1 is a diagram showing a schematic configuration of a content delivery system according to the present invention.
2 is a message flow diagram illustrating a content transmission process in the content delivery system according to the present invention.
3 is a diagram showing the syntax of a status report message in the content delivery system according to the present invention.
4 is a diagram briefly showing the configuration of a network node in the content delivery system according to the present invention.
5 is a diagram showing the configuration of a CDN management device in the content delivery system according to the present invention.
6 is a diagram for explaining a computing system in which a CDN management device according to the present invention is implemented.

In order to clarify the characteristics and advantages of the problem solving means of the present invention, the present invention will be described in more detail with reference to specific embodiments of the present invention shown in the accompanying drawings.

However, detailed descriptions of well-known functions or configurations that may obscure the gist of the present invention will be omitted in the following description and accompanying drawings. In addition, it should be noted that the same components are indicated by the same reference numerals throughout the drawings as much as possible.

The terms or words used in the following description and drawings should not be construed as being limited to a common or dictionary meaning, and the inventor may appropriately define the concept of terms for explaining his/her invention in the best way. It should be interpreted as a meaning and concept consistent with the technical idea of the present invention based on the principle that there is. Therefore, the embodiments described in this specification and the configurations shown in the drawings are only one of the most preferred embodiments of the present invention, and do not represent all of the technical ideas of the present invention. It should be understood that there may be equivalents and variations.

In addition, terms including ordinal numbers, such as first and second, are used to describe various components, and are used only for the purpose of distinguishing one component from other components, and to limit the components. Not used. For example, a second element may be termed a first element, and similarly, a first element may be termed a second element, without departing from the scope of the present invention.

Additionally, when an element is referred to as being “connected” or “connected” to another element, it means that it is logically or physically connected or capable of being connected. In other words, it should be understood that a component may be directly connected or connected to another component, but another component may exist in the middle, or may be indirectly connected or connected.

In addition, terms used in this specification are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In addition, terms such as "include" or "having" described in this specification are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or the other It should be understood that the above does not preclude the possibility of the presence or addition of other features, numbers, steps, operations, components, parts, or combinations thereof.

In the following description and claims, a "network" or "communications network" is defined as one or more data links that enable the transfer of electronic data between computer systems and/or modules. When information is transmitted or provided to a computer system over a network or other (wired, wireless, or combination of wired or wireless) communication connection, the connection may be understood as a computer-readable medium. Computer readable instructions include, for example, instructions and data that cause a general purpose or special purpose computer system to perform a particular function or group of functions. Computer executable instructions may be, for example, binary, intermediate format instructions, such as assembly language, or even source code.

The invention may also be practiced in distributed system environments where tasks are performed by both local and remote computer systems linked by wired data links, wireless data links, or a combination of wired and wireless data links through a network. In a distributed system environment, program modules may be located in local and remote memory storage devices.

In addition, the streaming (Streaming) service described in this specification means to provide a variety of content, such as audio or video services in a streaming method. Here, the streaming method is a technology in which file transmission and playback are performed together to reduce waiting time and is not limited by the storage capacity of the receiving side, and means a method of receiving data in units of streaming data packets and playing them immediately upon receipt. Such streaming can be divided into VOD streaming, which provides content stored in a streaming server according to a user's request, and live streaming, which broadcasts content data at a fixed time, such as Internet radio broadcasting and Internet broadcasting. Streaming applied to the present invention can be applied to both of the above methods.

Hereinafter, the main configuration of the streaming service providing system according to an embodiment of the present invention will be described first.

1 is a diagram showing a schematic configuration of a content delivery system according to the present invention.

Referring to FIG. 1 , the content delivery system according to the present invention may include a plurality of network nodes 100 , a client device 200 , and a CDN management device 300 . The plurality of network nodes 100 , the client device 200 , and the CDN management device 300 described above are interconnected through an arbitrary network 10 .

The network 10 refers to a transmission medium for data transmission and reception between the network node 100, the client device 200, and the CDN management device 300, and in particular, various types, such as an intranet, rather than a single communication network type. A communication network implemented using various types of wired and wireless communication technologies such as a network, a mobile communication network, and a satellite communication network may be in a mixed form.

In addition, the network 10 may include a mobile network including a plurality of radio access networks (not shown) and a core network (not shown), and an external network, such as an Internet network (not shown). Here, the wireless access network (not shown) constituting the mobile network is an access network that performs wireless communication with the client device 200, for example, BS (Base Station), BTS (Base Transceiver Station), NodeB, eNodeB, etc. It may be implemented with a plurality of base stations and base station controllers such as a base station controller (BSC) and a radio network controller (RNC).

In another method, by separating a digital unit (hereinafter referred to as DU) that performs processing of the base band of the base station and a radio unit (hereinafter referred to as RU) that performs processing of the RF stage, , a plurality of RUs may be installed in each service area, and the plurality of RUs may be connected to a DU concentration station that centralizes the plurality of DUs.

In addition, the core network constituting the mobile network together with the wireless access network serves to connect the wired/wireless access network and an external network, for example, an Internet network (not shown).

As described above, the core network is a network system that performs major functions for mobile communication services such as mobility control and switching between wired and wireless access networks, and performs circuit switching or packet switching. It manages and controls the packet flow within the network. In addition, the core network (not shown) manages inter-frequency mobility and plays a role for interworking with traffic in an access network (not shown) and a core network (not shown) and other networks, for example, an Internet network (not shown). may be The core network (not shown) may further include a Mobile Switching Center (MSC), Home Location Register (HLR), Mobile Mobility Entity (MME), Home Subscriber Server (HSS), and the like, in addition to the above configuration.

In addition, the Internet network refers to a common open communication network in which information is exchanged according to the TCP / IP protocol, that is, a public network, and is connected to the streaming server 200 to transmit streaming data provided from the streaming server 200 as a core. Through a network (not shown) and a wired/wireless access network (not shown), it may play a role of providing the terminal 100.

In addition, mobile packets transmitted and received on the mobile network may be transmitted through a GPRS Tunneling Protocol (GTP) tunnel unlike an Internet network (not shown). For example, when the client device 200 transmits a content request message and transmits an IP packet including source address information and destination address information to a radio access network, a base station (eg, eNodeB) of the radio access network transmits the IP packet. The mobile packet is converted into a mobile packet in which a GTP header, UDP header, and IP header for GTP tunneling are added to the packet and transmitted to the core network. In this case, the GTP header may include tunneling identification information (TEID; Tunneling End poing ID) allocated to the client device 200 . The core network may remove the GTP header, the UDP header, and the IP header for GTP tunneling, and transmit the original IP packet transmitted by the client device 200 to the Internet network as a destination.

Above, the structure of the network 10 to which the present invention is applied has been briefly described. Additionally, the network 10 may include a cloud computing system capable of storing computing resources such as hardware and software and providing computing resources required by clients to corresponding terminals. Here, cloud computing refers to a computer environment in which information is permanently stored in a server on the Internet and temporarily stored in client terminals such as desktops, tablet computers, laptops, netbooks, and smartphones. It refers to a computer environment access network that stores information in a server on the Internet and makes it available anytime and anywhere through various IT devices.

In addition, the network 10 includes a closed network such as a local area network (LAN) and a wide area network (WAN) and an open network such as the Internet, as well as code division multiple access (CDMA) and wideband code division (WCDMA). Multiple Access), Global System for Mobile Communications (GSM), Long Term Evolution (LTE), and Evolved Packet Core (EPC), which are recently attracting attention, and next-generation networks to be implemented in the future.

The network node 100 is a network device that stores at least some or all of the contents to be served and streams and transmits the stored contents according to the request of the client device 200, and the network to which the client device 200 is connected ( 10) can be distributed in the phase. More specifically, the network node 100 may be distributedly disposed on a core network of a mobile network and connected to an edge node of a core network to which each radio access network is connected.

In particular, the network node 10 according to the present invention is a device capable of transmitting and receiving stored content according to the MMT standard, and may be a Media Aware Network Entity (MANE) of MMT.

For reference, in the MMT protocol structure, an MMTP packet has a variable length packet format, and the MMTP payload is divided into a Media Processing Unit (MPU) mode, a General File Delivery (GFD) mode, and a signaling message mode. The MPU mode is a mode of packetizing and streaming a file, and the GFD mode is a download mode of a general file.

In MPU mode, an MMTP packet consists of a 20-byte MMTP header, an MPU header, and an MPU payload. The MPU is divided into timed media with a 24-byte header and non-timed media with a 14-byte header.

The network node 100 may transmit and receive MMTP packets according to the MMT protocol, and analyze and process the MMTP packets. At this time, the MMTP packet may be transmitted in a streaming method.

And the client device 200 is a user-side device using the content delivery service according to the present invention, requests transmission of the content selected by the user, and transmits MMTP packets transmitted in a streaming manner from any one network node 100 corresponding to the request. can be received and played.

The CDN management device 300 is a device for managing the plurality of network nodes 100 and performing load balancing of content delivery services.

In the content delivery system according to the present invention, in performing the content streaming service from the network node 100 to the client device 200, state information of each of the plurality of network nodes 100 through the CDN management device 300 is collected, selects the network node 100 to transmit the requested content to the client device 200 that has requested the content based on the collected state information, and provides corresponding route information to the client device 200.

The CDN management device 300 communicates with a plurality of network nodes 100 through the network 10 .

An operation of the content delivery service in the content delivery system configured as described above will be described with reference to FIG. 2 .

2 is a message flow diagram illustrating a content transmission process in a content delivery system according to the present invention.

Referring to FIG. 2 , in the content delivery system according to the present invention, the CDN management device 300 periodically collects state information from a plurality of network nodes 100 (S105). The collection of the status information may be performed in a form in which each network node 100 transmits status information related to its load to the CDN management device 300 through a status report message.

At this time, a status report message for collecting status information of each network node 100 may be defined in the structure shown in FIG. 3 .

Referring to FIG. 3 , the status report message (MSR_message) may include message identification information (message_id), version information (version), and length information (length) as header information. The load (message_payload) is classified for each network node 100 by node identification information (num_MANE) and transmitted.

The state information includes the IP address (MANE_IP) of the network node, the operation mode (MANE_mode) of the network node, current session information (Current session), maximum session capacity (Max session capacity), response time (Response time), CPU load ( CPU_loas), GPU load (GPU_load), memory usage (RAM_usage), virtualization flag (Virtual_flag), valid start time (valid_time_start), valid period (valid_time_duration), and measurement time (Measure_time).

The IP address (MANE_IP) of the network node is an IP address assigned to the network node 100 identified by the node identification information (num_MANE) and can be expressed as a 128-bit field.

The operation mode (MANE_mode) of the network node is information representing the functional class of the network node 100 identified by the node identification information (num_MANE), and includes, for example, three classes A, B, and C defined in the MMT protocol. can represent any one of them. For example, the operation mode (MANE_mode) may be indicated in a 2-bit long field, and a value of 0 may indicate class A, a value of 1 may indicate class B, and a value of 2 may indicate class C.

The current session information (Current session) indicates the number of sessions currently connected to the network node 100 identified by the node identification information (num_MANE) and can be expressed in 32 bits. The session means a session connecting between the network node 100 and the client device 200 .

The maximum session capacity indicates the maximum number of connectable sessions in the network node 100 identified by the node identification information (num_MANE), and may be expressed in 32 bits.

Response time is the average response time for requests, can be expressed in milliseconds, and can be defined as a field length of 16 bits.

The CPU load (CPU_loas) and the GPU load (GPU_load) are current loads of the CPU and GPU provided in the network node 100 identified by the node identification information (num_MANE) and may be expressed as %.

The memory usage (RAM_usage) is the current usage of the memory (RAM) included in the network node 100 identified by the node identification information (num_MANE), and may be expressed as %.

Each of the CPU load (CPU_loas), GPU load (GPU_load), and memory usage (RAM_usage) has a field length of 8 bits.

The virtualization flag (Virtual_flag) is information indicating whether the network node 100 identified by the node identification information (num_MANE) is a dedicated network node (dedicated MANE) or a temporarily created virtual network node (virtualized MANE). For example, a value of 0 may mean a dedicated network node, and a value of 1 may mean a virtual network node.

The valid start time (valid_time_start) and the valid period (valid_time_duration) are used to define the valid time of a virtual network node when the network node 100 identified by the node identification information (num_MANE) is a temporarily constructed virtual network node. As information, each indicates the creation time of the virtual network and the period during which the virtual network node is maintained.

The measurement time (Measure_time) is for distinguishing the time at which the status information is measured, that is, it can be represented as the generation time of the status report message.

The CDN management device 300 stores status information of each network node 100 that is periodically transmitted through a status report message structured as described above. At this time, the stored status information is the most recently received status. It is updated with the status information of the report message.

In addition, an arbitrary client device 200 requests content according to a user's request. At this time, the content request of the client device 200 is transmitted to the CDN management device 300 (S110). Here, the content request may be made through, for example, a domain name query message (DNS query) including content address information or a content request message (eg, HTTP request message).

Upon receiving the content request from the client device 200, the CDN management device 300 compares previously stored state information of a plurality of network nodes 100 and selects a network node to transmit content to the client device 200. Do (S115). Here, the selection of the network node that transmits the content is one of the IP address of the network node 100, the number of current sessions, response time, load information, memory usage, whether it is virtual or dedicated, and the validity period in the case of a virtual network node. This can be done based on a combination of the above criteria. For example, simply, the network node 100 with the fastest current response time may be selected, the network node with the least CPU or GPU load may be selected, or each network node 100 may be combined by combining two or more state information. ), and the calculated load index can be compared and selected.

When the network node 100 to transmit content is selected in this way, the CDN management device 300 transmits information on the selected network node to the client device 200 through a response message (S120). The response message may be implemented as a network node notification (MFN: MANE Function Notification) message notifying a network node to transmit content, and the network node notification message includes address information (source URL) of the selected network node 100, It may include a package access (PA), a package ID (ID), and an asset ID (asset ID).

The client device 200 refers to the network node notification message, connects to the corresponding network node 100 and requests content (S125), and in response, transmits data of the content requested from the corresponding network node 100. It is received and reproduced (S130).

As described above, in providing an MMT-based content delivery service, the present invention checks the status of network nodes 100 operating as CDN nodes using a status report message and a network node notification message to perform load balancing. can

4 is a diagram briefly showing the configuration of the network node 100 in the content delivery system according to the present invention.

The network node 100 is a device for receiving and caching content data transmitted over the network 10 and transmitting the cached content data to the client device 200, comprising a caching module 110 and a content transmission module 120. ) and a control module 130.

The caching module 110 stores content data, and the content delivery module 120 transmits the content data stored in the caching module 110 to the client device 200 in a predetermined transmission method, for example, a streaming method.

At this time, the control module 130, as a means for controlling the overall operation of the network node 100, checks whether the content data requested by the client device 200 is stored in the caching module 110, In this case, it is determined as a cache hit and the stored content data is transmitted to the client device 200 . On the other hand, if not stored, content data transmitted from an origin server according to a preset caching policy may be received and stored in the caching module 110 . In particular, in the present invention, the control module 130 periodically checks the status of the network node 100, extracts status information accordingly, and transmits the status information to the CDN management device 300 through the status report message. .

5 is a diagram showing the configuration of the CDN management device 300 in the content delivery system according to the present invention.

Referring to FIG. 5 , the CDN management device 300 may include a control module 310, a status information collection module 320, and a status information DB 330.

The control module 310 is a component that controls the overall operation of the CDN management device 300, controls state information collection processing of the network nodes 100, and performs content request and response processing of the client device 200. .

The state information collection module 320 collects state information from a plurality of network nodes 100 installed on the network 10 . The collection of the status information may be performed by receiving a status report message as shown in FIG. 3 . In addition, the status information collection module 320 may request a status information report from each network node 100 at predetermined intervals under the control of the control module 310 and receive the status report message as a response.

The state information DB 330 stores state information of the plurality of network nodes 100 collected by the state information collection module 320 . At this time, based on the periodically collected status information, the status information of the plurality of network nodes 100 may be updated to the latest status information.

The CDN management device 300 configured as described above controls the state information collection module 320 to collect state information from a plurality of network nodes 100 and store it in the state information DB 330, and then the client device ( When content is requested from 200), a network node to transmit content to the client device 200 is selected from among a plurality of network nodes 100 based on the stored state information, and the information about it is sent to the network node through a network node notification message. It is provided to the client device 200. At this time, the selection of the network node may be made according to a preset load balancing rule.

The CDN management device 300 configured as described above may be implemented by software or a combination of hardware and software, and may be specifically implemented on a computing system as shown in FIG. 6 .

6 is a diagram schematically illustrating a hardware structure of a computing device in which a CDN management device 300 according to the present invention is implemented.

A computing system in which the present invention is implemented includes at least one processor 61, a network interface 62, a memory 63, and an input/output interface 64 connected by a system bus.

The processor 61 loads and executes a program stored in the memory 63, thereby performing a predetermined function according to the program.

A program loaded and executed by the processor 61 may be an operating system (OS) program, one or more application programs, a program module, a program code including one or more program modules, and the like.

Also, the processor 61 may be a single-threaded processor in one implementation example, and may be a multi-threaded processor in another implementation example.

The method and apparatus according to the present invention may be implemented by being implemented as a program, stored in the memory 63, and then loaded and executed by the processor 61.

The memory 63 is for storage of computer executable instructions, data structures, program modules, and other data, and may include read only memory (ROM) and random access memory (RAM), and is used when the computing device starts up. It also stores programs containing the basic routines that help transfer information between components within the . The memory 63 may further store a state information DB 330 .

In addition, the computing system to which the present invention is applied includes a network interface 62 for receiving data from an external source and/or transmitting data to an external source. In the present invention, the CDN management device 300 receives a status report message from the network node 100 through the network interface 62 of the computing system, receives a request from the client device 200, and receives a network corresponding thereto. Nodes can send report messages.

In addition, the computing system may receive commands and information from a user through various input devices such as a keyboard, a pointing device, a microphone, a joystick, a game pad, a scanner, and the like through an input/output interface 64 connected to a system bus. . Commands and information input from the input/output interface 24 may be transferred to and processed by the processor 61, and the processing result may be returned to a display device such as a monitor or LCD or a speaker or microphone through the input/output interface 24. It can be output to various output devices such as an audio device.

The input/output interface 64 is a very common interface such as, for example, a serial port interface, a PS/2 interface, a parallel port interface, a USB interface, an Institute of Electrical and Electronics Engineers (IEEE) 1394 interface (i.e., a FireWire interface). Any of a variety of different interfaces can be logically represented, or even a combination of different interfaces can be logically represented.

In addition, the input/output interface 64 is connected to a modem, and can receive data from an external source or transmit data to an external source through this modem.

In a network environment, program modules or parts thereof related to the present invention may be stored in a modem connected to the input/output interface 64 or another computing device connected through the network interface 62 and operated in a distributed structure.

A computer program (also known as a program, software, software application, script or code) mounted on the computing system and executing the method according to the present invention is a compiled or interpreted language or a programming language including a priori or procedural language. It can be written in any form and can be deployed in any form, including stand-alone programs, modules, components, subroutines, or other units suitable for use in a computer environment. A computer program does not necessarily correspond to a file in a file system. A program may be in a single file provided to the requested program, or in multiple interacting files (e.g., one or more modules, subprograms, or files that store portions of code), or parts of files that hold other programs or data. (eg, one or more scripts stored within a markup language document). A computer program may be deployed to be executed on a single computer or multiple computers located at one site or distributed across multiple sites and interconnected by a communication network.

Computer readable media suitable for storing computer program instructions and data include semiconductor memory devices such as EPROM, EEPROM and flash memory devices, magnetic disks such as internal hard disks or external disks, magneto-optical disks and CD-ROMs. and all forms of non-volatile memory, media and memory devices, including DVD-ROM disks. The processor and memory may be supplemented by, or incorporated into, special purpose logic circuitry.

In addition, while this specification contains many specific implementation details, they should not be construed as limiting on the scope of any invention or what is claimed, but rather on features that may be unique to a particular embodiment of a particular invention. It should be understood as an explanation. Certain features that are described in this specification in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments individually or in any suitable subcombination. Further, while features may operate in particular combinations and are initially depicted as such claimed, one or more features from a claimed combination may in some cases be excluded from that combination, and the claimed combination is a subcombination. or sub-combination variations.

Similarly, while actions are depicted in the drawings in a particular order, it should not be construed as requiring that those actions be performed in the specific order shown or in the sequential order, or that all depicted actions must be performed to obtain desired results. In certain cases, multitasking and parallel processing can be advantageous. Further, the separation of various system components in the embodiments described above should not be understood as requiring such separation in all embodiments, and the program components and systems described may generally be integrated together into a single software product or packaged into multiple software products. You have to understand that you can.

Specific embodiments of the subject matter described herein have been described. Other embodiments are within the scope of the following claims. For example, the actions recited in the claims can be performed in a different order and still achieve desirable results. As an example, the processes depicted in the accompanying drawings do not necessarily require the specific depicted order or sequential order in order to obtain desirable results. In certain implementations, multitasking and parallel processing may be advantageous.

The present invention collects status information of a plurality of network nodes that cache and transmit contents according to the MMT protocol through a status report message, and selects a network node to transmit contents to a client device based on the status information collected in this way. By transmitting information to a client device through a network node notification message, load balancing of a plurality of network nodes is possible in an MMT-based content transmission service.

In addition, through this, there is an effect of further improving the service quality of the MMT-based content transmission service.

10: network
100: network node
200: client device
300: CDN (Contents Delivery Network) management device

Claims (8)

A method for selecting an optimal network node for content transmission of a CDN (Contents Delivery network) management device interoperating with a plurality of network nodes and client devices that cache and transmit content based on the MMT (MPEG Media Transport) protocol, the method comprising:
The CDN management device
Receiving and storing a state information message including state information of each network node from a plurality of network nodes that transmit and receive MMTP packets according to the MMT protocol;
selecting a network node to transmit content from among a plurality of network nodes based on the state information when content transmission is requested from the client device;
Transmitting to the client device via a network node notification message containing information on the selected network node;
The selection step is
IP address of the network node (MANE_IP), operation mode of the network node (MANE_mode), current session information (Current session), maximum session capacity (Max session capacity), response time (Response time), CPU load (CPU_loas), GPU Among load (GPU_load), memory usage (RAM_usage), virtualization flag indicating whether the network node is a temporarily created virtual network node (Virtual_flag), valid start time (valid_time_start), valid period (valid_time_duration), and measurement time (Measure_time). An optimal network node selection method for content transmission, characterized in that selecting a network node to transmit the content according to the load index of each network node calculated by combining one or more of them. The method of claim 1, wherein the status information message
Network node IP address (MANE_IP), network node operation mode (MANE_mode), current session information (Current session), maximum session capacity (Max session capacity), response time (Response time), CPU load (CPU_loas), GPU load (GPU_load), memory usage (RAM_usage), virtualization flag indicating whether the network node is a temporarily created virtual network node (Virtual_flag), and measurement time (Measure_time). Node selection method. The method of claim 1, wherein the status information message
When the network node is a virtual network node, content transmission further comprising a valid start time (valid_time_start) indicating a creation time of the virtual network node and a valid period (valid_time_duration) indicating a maintenance time of the virtual network node. Optimal network node selection method for The method of claim 3, wherein the network node notification message
An optimal network for content transmission characterized in that it includes at least one of address information (source URL), PA (Package Access) information, package ID (Package ID), and asset ID (asset ID) of the selected network node (100). Node selection method. delete A computer-readable recording medium storing a program for executing the optimal network node selection method for content transmission according to any one of claims 1 to 4. A program implemented to execute the optimal network node selection method for content transmission according to any one of claims 1 to 4 and stored in a computer readable recording medium. a state information DB for storing state information of a plurality of network nodes performing content caching and transmission based on the MMT protocol;
a status information collection module configured to collect status information by receiving status report messages transmitted from the plurality of network nodes transmitting and receiving MMTP packets according to the MMT protocol; and
When content transmission is requested from a client device, a network node to transmit content is selected from among a plurality of network nodes based on the status information, and transmitted to the client device through a network node notification message including information about the selected network node. Including a control module that
Among the plurality of network nodes, the network node to transmit the content,
IP address of the network node (MANE_IP), operation mode of the network node (MANE_mode), current session information (Current session), maximum session capacity (Max session capacity), response time (Response time), CPU load (CPU_loas), GPU Among load (GPU_load), memory usage (RAM_usage), virtualization flag indicating whether the network node is a temporarily created virtual network node (Virtual_flag), valid start time (valid_time_start), valid period (valid_time_duration), and measurement time (Measure_time). CDN management device, characterized in that selected according to the load index of each network node calculated by combining one or more.

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