KR20140100436A - Network node apparatus for information-centric networking and operating method of the network node apparatus - Google Patents

Abstract

Disclosed are a network node apparatus for information-centric networking and a method of operating the same. The network node apparatus according to an embodiment of the present invention has a separated network control plane and a data transfer plane, and manages location information of content on the data transfer plane in a centrally concentrated form. For example, the network node apparatus includes a content service coordination function (CSCF) for processing a content request from a user or an issue request from a content provider, a content delivery control function (CDCF) for selecting an optimum service node which will process the content request or the issue request, and a content delivery service function (CDSF) for providing the user with the requested content or downloading the content whose issue has been requested from the content provider to register the content.

Description

[0001] The present invention relates to a network node apparatus for information-centric networking and a method for operating the same,

The present invention relates to a network node apparatus for implementing information-centric networking (ICN) and a method of operating the network node apparatus.

Information-centric networking (ICN) is a method of communicating using an identifier of information to be acquired instead of an address of a communication target host. Using the information-centric networking method, a user connects to a host having information and provides an identifier of the information to be acquired to the network instead of fetching information, and the network then uses the identifier to find the information and returns it to the user .

Various methods such as Data-Oriented Network Architecture (DONA), Content-Centric Networking (CCN), and Publish-Subscribe Internet Technology (PURSUIT) have been proposed as information-centric networking methods. Among them, DONA and CCN are representative.

DONA is a research project centered on Teemu Koponen of the University of California at Berkeley, which defines ICNs that use information identifiers based on public keys. DONA proposes a communication model based on hierarchical network structure consisting of Resolution Handler (RH). The RH, when receiving the information request packet, manages the routing information for delivering it to the appropriate neighbor RH. In DONA, the information holder creates a register (REGISTER) packet to register the information in the DONA network and sends it to the adjacent RH. RH manages routing information based on this register (REGISTER) packet. The information requester creates a FIND packet containing the identifier of the requesting information and sends it to the nearest RH. Based on the routing information, the RH sends the FIND packet to the neighboring RH to be transmitted to the specific network node that is caching the information bearer or information.

CCN, a research project centered on Van Jacobson of the Palo Alto Research Center (PARC), is an ICN technology using hierarchical information identifiers. The information identifiers of the CCN are similar to URL (Uniform Resource Location) in that they are hierarchically structured, but differ from the URL in that they do not include address information. The CCN follows a request-response type communication model. The requesting entity creates an INTEREST packet, which is a request message, and sends it to the network. The network receiving the INTEREST packet transmits an INTEREST packet to the holder of the information. When the information holder receives the INTEREST packet, it creates a DATA packet in response to the DATA packet, and the DATA packet is transmitted to the person who requested the information again by the CCN network. In CCN, the routing nodes in the network have location information about all contents. Therefore, if the amount of content increases, the amount of information that the routing nodes need to maintain increases, thereby causing scalability problems.

In the case of DONA, the location information of the content is distributed and stored by using DHT (Distributed Hash Table) to solve the scalability problem. However, there is a problem that the DHT technology ignores the location information of nodes participating in the network. For example, assume that the nodes located in Seoul and the nodes located in Busan are connected by DHT. Let's say that a user located in Seoul wants to download file A through the DHT. Let us assume that this file A is stored in one of the nodes located in Seoul. Since the user does not know the location of A, in order to download A, first you have to query the location of A in DHT. However, due to the nature of DHT, the location information of file A may be stored in a node located in Busan, rather than in Seoul. Therefore, in order to use file A, it is necessary to inquire the location of A to the node located in Busan, receive the result, and then request A to the Seoul node having A. Therefore, the transmission path of the query packet sent to use one content may be considerably long, and unnecessary long distance traffic may occur.

In addition, both of the above-described DOAN and CCN are designed without considering an interworking interface between a business operator and a user. Moreover, since DONA operates only in a hierarchical network structure, it is limited to various types of networks.

One of the problems to be solved by the present invention is to provide an information-centric networking (ICN) that naturally cooperates with various networks including an IP (Internet Protocol) network, while facilitating the core functions of the ICN such as on-path caching A network node device for supporting ICNs, and an operation method thereof.

Another object of the present invention is to provide a network node apparatus and an operation method thereof for effectively ICN capable of effectively solving the scalability problem of routing nodes.

Another object of the present invention is to provide a network node apparatus and an operation method thereof for an ICN, which provides a user-friendly interface and an interface with which an existing enterprise can be easily interworked.

The present invention relates to a network node apparatus for information-centric networking, wherein a network control plane and a data transmission plane are separated from each other, and position information of contents is managed in a centralized form on a data plane .

According to an aspect of the present invention, there is provided a network node apparatus for information-centric networking, the network node apparatus comprising: a first node for receiving a content request for a first content from a user, A Content Service Coordination Function (CSCF) that queries and receives information and redirects the content request to the first content service node, a response to the query from the CSCF that received the content request A Content Delivery Control Function (CDCF) for selecting the first content service node from among one or more content service nodes having the first content and notifying the CSCF of the first content service node, and a server for receiving the redirected content request , The first content is transmitted to the user Features include content delivery services (Content Delivery Service Function, CDSF).

According to an aspect of the embodiment, the CSCF can identify the content identifier of the first content based on the content address information of the first content included in the received content request, and transmit the content identifier to the CDCF have.

According to another aspect of the embodiment, the CSCF finds the IP address information of the user, the content address information and the content identifier of the first content from the received content request, inserts it into the query to the CDCF, May select the first content service node to an optimal content service node that will process the content request based on network resource information including proximity, network topology, and availability.

According to another aspect of the present invention, the CDCF manages a content identifier of each content registered in a network and one or more pieces of content location information corresponding thereto in a predetermined database, and the CDSF, which receives the redirected content request, And transmit the first content to the user using the content position information of the first content obtained by communicating with the CDCF. In this case, when the first content is not stored in the storage or cache of the first content service node, the CDSF starts routing the content based on the content identifier of the first content, And transmit it to the user.

According to another aspect of this embodiment, the CSCF includes a content service functional entity that handles the content request and also causes the content request to be redirected, A service optimization functional entity for selecting the first content service node among the service nodes, and a service optimization functional entity for managing the content identifier of each content registered in the network and one or more pieces of content location information corresponding to the content identifier, A content name resolution functional entity, the CDSF comprising: a customer service functional entity for transmitting the first content to the user; and means for interacting with the content name resolution functional entity The first cone Come to find out the location information of the content transfer function tsu object thus routing the first import the primary content storage and the cache or content routing path may include (content transfer functional entity).

According to another aspect of the embodiment, upon receiving a request for issuing a second content from a content provider, the CSCF holds the issuance information of the second content and further processes the issuance request received by querying the CDCF In response to a query from the CSCF that received the issuance request, the CDCF selects the first issuance service node from one or more issuance service nodes and sends the issuance request to the CSCF You can tell. In this case, upon receiving the issuance request of the second content from the CSCF, the CDSF may download the second content to be issued from the content provider and store it together with the issuance information. Alternatively, the CSCF may include a content publication functional entity that handles the issuance request and generates a content identifier of the second content, and the CDCF may include, among the one or more issuance service nodes, A service optimization functional entity for selecting a first publication service node, a content name resolution function for managing a content identifier of each content registered in the network and one or more pieces of content location information corresponding to the content identifier, And the CDSF may include a customer service functional entity that downloads the second content from the content provider and stores the downloaded content and issue information .

According to another aspect of the present invention, there is provided a network node device for providing information-centric networking in a network including a plurality of service nodes each having a cache and at least a part of the plurality of service nodes, . Wherein the network node device comprises: a Content Service Coordination Function (CSCF) for causing the content request to be redirected to a first service node when receiving a content request for a first content from a user; A Content Delivery Control Function (CSCF) for selecting the first service node to process the content request among the one or more service nodes holding the first content and notifying the CSCF of the first service node in response to a query from the CSCF, And a content delivery service function (CDSF) for transmitting the first content to the user upon receiving the redirected content request.

According to another aspect of the present invention, there is provided a content service method for a network node device for information-centric networking, the method comprising: (a) receiving a content request for a first content from a user, (CSCF), (b) the CSCF queries the Content Delivery Control Function (CDCF) for the first content service node to process the content request, (c) Selecting a first content service node from among one or more content service nodes in which the CDCF holds the first content and informing the CSCF of the first content service node; (d) if the CSCF requests the first content service node (E) redirecting the redirected content delivery service Function (Function Content Delivery Service, CDSF) is transmitting the first content to the user.

According to an aspect of the embodiment, in step (b), the CSCF determines a content identifier of the first content based on content address information of the first content included in the received content request, To the CDCF. In this case, the step (d) comprises the steps of: (d1) requesting the CSCF to redirect a content request for the first content to the first content service node; and (d2) And receiving a content request using the identifier from the user. The step (e) further comprises: (e1) the CDSF receiving the content request requesting the first content from the CDCF using the content identifier and the CDCF, Or may be routed along the content routing path and forwarded to the CDSF.

According to another aspect of the present invention, there is provided a content issuing method for a network node apparatus for information-centric networking, the method comprising: (a) receiving a request for issuing a first content from a content provider, (B) the CSCF generates a content identifier for the first content; (c) the CSCF sends information about the first issue service node to process the issue request (CDCF), the CDCF selecting a first issue service node to process the issue request among at least one issue service node and responding to the CSCF, (e) the CSCF sends a publish request for the first content to a content delivery service function (CDSF) System and (f) the CDSF includes the step to download the first content from the content provider.

According to an embodiment of the present invention, in the step (c), the CSCF includes transmitting a content registration request message including the content identifier of the first content and the address information of the content provider to the CDCF, In step (d), the CDCF may include transmitting a content registration response message including address information of the first issuance service node to the CSCF. In this case, the step (d) may further include: (d1) if the content name resolution functional entity of the CDCF that has received the content registration request message transmits a publication service node selection request to the service optimization function object (d2) the service optimization function object selecting the first issue service node among the one or more issue service nodes, and (d3) And transmitting a publication service node selection response including the address information of the service node to the content name resolution function object.

According to another aspect of the present invention, the content issuing method further comprises: (g) registering the first content downloaded from the customer service functional entity of the CDSF in a content transfer functional entity And (h) the CDSF sending a content issue response to the CSCF in response to the content issue request of step (e).

According to another aspect of the present invention, there is provided a content service method through a Content Service Coordination Function (CSCF) of a network node apparatus for information-centric networking, the method comprising: (a) (B) querying a Content Delivery Control Function (CDCF) for information about a first content service node to process the content request; (c) Receiving information about the first content service node selected by the CDCF from one or more content service nodes having a first content, and (d) receiving a content delivery service function (CDSF) The content request to the first content service node to send a first content to the user So as to be redirected.

According to an aspect of the embodiment, the content identifier of the first content is obtained based on the content address information of the first content included in the content request received in step (b) Lt; / RTI > In this case, the step (d) includes a step of requesting the user to redirect the content request for the first content to the first content service node, and the user who receives the redirect request transmits the content identifier To the CDSF. The CDSF, after receiving the content request, requests the first content to the CDCF using the content identifier, and the CDCF also obtains the first content from the storage or cache, And may be routed along the routing path to the CDSF.

According to another aspect of the present invention, there is provided a content issuance method through a Content Service Coordination Function (CSCF) of a network node apparatus for information-centric networking, the method comprising: (a) (B) generating a content identifier for the first content; (c) transmitting information about a first publishing service node to process the issuance request to a content delivery control function (D) receiving information about a first issue service node that will process the issue request selected by the CDCF from one or more issue service nodes, and (e) A content delivery service function (CDSF) is adapted to download the first content from the content provider A publication request for the first content and transmitting to the CDCF.

According to an aspect of the embodiment, the step (c) includes transmitting, to the CDCF, a content registration request message including a content identifier of the first content and address information of the content provider, ) May include receiving from the CDCF a content registration response message including address information of the first issuance service node. In this case, in step (d), the content name resolution functional entity of the CDCF, which has received the content registration request message, transmits a service selection request to the service optimization functional object of the CDCF and the service optimization function object may transmit an issue service node selection response including the address information of the first issue service node selected from the one or more issue service nodes to the content name resolution function object.

According to another aspect of the embodiment, (f) receiving the content issue response in response to the content issue request from the CDSF that has registered the downloaded first content.

According to the above-described embodiment of the present invention, a network node device for realizing information-centric networking (ICN), for example, a service node (for example, a router) The amount of information can be significantly reduced. According to this, even if the amount of content to be served increases, the facility investment and management burden do not increase in a specific network node device, which can support the scalability of the scale.

According to the embodiment of the present invention, a content identifier unique to each content and address information in which the content is stored or cached are managed in association with each other. Accordingly, it is possible to link the information-centric networking technology to the existing IP-based service network such as CDN and its users.

In addition, according to an embodiment of the present invention, a network control plane and a data transmission plane are separated from each other, so that position information of contents is not managed by an object (for example, a router) Centralized management in the control plane. Therefore, even if the content to be managed increases, efficient management is possible. In addition, since an optimal service node (a content service node and an issue service node) is selected in consideration of the context information of a service requester (user or content provider) and a service is provided through the selected service node, efficient traffic management This is possible.

1 is a block diagram illustrating a configuration of a network node device for an information-centric networking (ICN) according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating functions of the network node apparatus of FIG. 1 as a relation between a control node and service nodes.
FIG. 3 is a view showing an example of a relationship among functions in a content issuing procedure through the network node apparatus of FIG. 1; FIG.
4 is a diagram showing an example of a message flow diagram between functions in a content issuing procedure through the network node apparatus of FIG. 1;
FIG. 5 is a diagram showing an example of a relationship among functions in a content service procedure through the network node apparatus of FIG. 1. FIG.
FIG. 6 is a diagram showing an example of a message flow diagram between functions in a content service procedure through the network node apparatus of FIG. 1;

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The terms used in the following embodiments are terms selected in consideration of the functions in the embodiments, and the meaning of the terms may vary depending on the user, the intention or custom of the operator, and the like. Therefore, the meaning of a term used herein should be interpreted according to its definition when it is specifically defined in the present specification, and in the case where there is no specific definition, a person skilled in the art will generally understand it. In the following description, well-known functions or constructions are not described in detail to avoid unnecessary obscuration of the technical idea of the present invention.

1 is a block diagram illustrating a configuration of a network node device for an information-centric networking (ICN) according to an embodiment of the present invention. 1, the network node apparatus 100 includes a content service coordination function (CSCF) 110, a content delivery control function (CDCF) 120, a content delivery service function Service Function, CDSF, 130). The division of the network node apparatus 100 is an example of a logical division according to its specific function, and should not be construed as limited.

In addition, the network node apparatus 100 may transmit an identifier of a content, for example, a content identifier of a content in a Smart Ubiquitous Network (SUN) defined in a network implemented with information-centric networking, such as an International Telecommunication Union Telecommunication standardization sector Name, ID, < / RTI > and also for a distributed service node to route the content to a user. All of the service node of the SNU may include all the components included in the network node apparatus 100, but the present invention is not limited thereto. In some implementations, a particular service node may have all of the components, while other service nodes may include only some of the components. However, even in the latter case, at least one of the above-described components is provided from the viewpoint of the entire network. For example, one or more of the functions 110, 120, and 130 described above may be provided across two or more network node devices 100. For example, The components of the network node apparatus 100 shown in FIG. 1 may be integrally implemented as a whole or may be implemented as two or more separate components.

The network node apparatus 100 transmits the content (or information) to the network in accordance with a predetermined procedure, such as giving an identifier unique to the content requested to be published, if there is a content publication request from the content provider 10 (content provider) . The user 20 can make a content request such as a request for transmission of the content (or information) by using a means (name or identifier, etc.) for identifying the content such as the name of the content, 100, upon receipt of the content transmission request, finds the requested content among the registered contents and transmits the requested content to the user.

To this end, the network node device 100 has a content publication capability, a content caching capability, a content service provisioning capability, and a content routing capability can do.

The content publishing capability refers to processing a publishing request of a content provider who intends to register the content in a network in which information-centric networking is implemented. The content request of the content provider may include detailed content information including a content source or location information of a content source or an origin. A content source or a content source is an object (e.g., a server) that a content provider stores while managing the corresponding content. Based on this content information, the network node apparatus 100 downloads the content from the content source and stores the content in the storage of the network. Content caching capability refers to distributing content to a content cache of a service node. Accordingly, the content traffic can be optimized by reducing the distance between the content source and the end user. For example, the content may be dynamically distributed to a plurality of caches (i. E., A plurality of service nodes) along the content routing path. Content service provision capability refers to processing content requests or content transfer requests from end users. The network node apparatus 100 selects an appropriate content using a content identifier determined according to the context of the user and also selects an optimal content location (e.g., , The location of the service node where the content is stored or cached). At this time, the network node device 100 may find the location (storage or cache) where the content is stored in terms of location and / or traffic optimization. The content routing capability refers to locating a content location based on a content name such as a content identifier. The content can be fetched using the content routing capability and transmitted to the requesting service node.

Hereinafter, each of the functional components constituting the network node apparatus 100 of FIG. 1 for providing the above-described capabilities through interaction among the functional components will be described in detail.

The content service coordination function (CSCF) 110 coordinates content services including content publishing between the content provider 10 and the end user 20. To this end, the content service coordination function 110 handles the issue of content from the content provider 10 or a request for content from the end user 20 (e.g., content download). To this end, the content service coordination function 110 may include a Content Publication Functional Entity (CP-FE) 112 and a Service Request Routing Functional Entity (SR-FE) 114 have.

The content service coordination function (CSCF) 110 serves as a gateway to the object using the network in which the information-oriented networking is implemented, that is, a gateway. That is, the content service coordinating function (CSCF) 110 serves as a gateway for the content provider (CP) 10 or the user 20 to access the information center network. More specifically, it operates as a content publishing gateway that receives a request for content issuance from the content provider 10, which is the first customer, and downloads content requested to be published from the origin server where the content is located. When a content service (download, etc.) request is received from the user 20 using the content, which is the second customer, the content service coordination function (CSCF) 110 searches for a node to be requested by the user, As shown in FIG.

First, the content service coordinating function (CSCF) 110 registers and also stores the content information if there is a content issuance request from the content provider 10. The content service coordination function (CSCF) 110 then starts downloading the content from the content source and registers it with the issue information. To this end, the content service coordination function 110 comprises a content publishing functional object (CP-FE) 112.

The content publishing function object (CP-FE) 112 processes the issuance of the content in response to a request from the content provider 10, and can provide the issuance interface to the content provider 10 for this purpose. The information collected from the issue interface includes meta information such as an original name of a content and a content type, and among these meta information, a network address of an origin server in which a content provider actually stores contents may be included . The content issuing function object (CP-FE) 112 generates a unique content identifier for identifying the content on the network based on the meta information of the content requested by the content provider 10 to be issued.

The content issuing function object (CP-FE) 112 receives information about a service node to download and store the content in a network in which information-centric networking is implemented, using the network address of the first server received from the content provider 10 To the content delivery control function 120 by inquiring. The content publishing function object (CP-FE) 112 also transmits information about the content access method in the initial server or the content identifier generated along with the name to the service node. The content delivery service function (CDSF) 130 of the service node, or more specifically, the customer service functional entity (CS-FE) 132 performs a procedure of acquiring contents from the initial server, The procedure is complete.

The content service coordination function (CSCF) 110 serves to allow the user 20 to redirect the request to the optimal service node when requesting the content. The optimal service node may be determined by the content delivery control function (CDCF) 120. To this end, the content service coordination function (CSCF) 110 includes a service request routing functional object (SR-FE) 114.

The Service Request Routing Function Object (SR-FE) 114 allows the user 20 to acquire or use the content in response to a request from the content user 20. Typically, the content user 20 makes a content request through a content user interface such as a portal or an app. At this time, the service request routing function object (SR-FE) 114 first processes the content request of the content user 20 Performs the function. The service request routing function object (SR-FE) 114, when a content request is received from the user 20, finds the content identifier desired by the user. The service request routing function object (SR-FE) 114 performs a process of selecting a service node processing a content request from the user 20. In one example, the service request routing function object (SR-FE) 114 queries the content delivery control function (CDCF) 120 via the network address information of the content user 20 The service node to be processed can be selected. Lastly, the service request routing function object (SR-FE) 114 allows the content identifier of the found content and the content request of the user 20 to be transmitted to the selected service node.

The content delivery control function (CDCF) 120, as a function of the network control plane, monitors network service resources and manages the content name and location information of the content. More specifically, the content delivery control function (CDCF) 120 obtains content location information according to a given content identifier while managing information on network resources, i.e., service nodes, which have content in a local storage or cache. Based on this information, the content delivery control function (CDCF) 120 determines an optimal service node for content delivery or content service provisioning. The content delivery control function (CDCF) 120 includes a Service Optimization Functional Entity (SO-FE) 122 and a Content Name Resolution Functional Entity (CR-FE) . ≪ / RTI >

The service optimization function object (SO-FE) 122 collects the status of the resource and usage information for providing the content service, and performs the management role optimized for the service through the collected information. The resource information collection function of the service optimization function object (SO-FE) 122 includes collecting status information from the service nodes together with the network status information from the service nodes and the network formed through the link between them. In addition, the optimization selection function of the service optimization function object (SO-FE, 122) plays a role of finding an optimal service node for content publication or content service provision based on the network address. In order to do this, location information extraction for an optimal service node among a plurality of service nodes in which the content is stored is performed in cooperation with a content name resolution functional object (CR-FE) 124 in consideration of proximity to the location of the corresponding content (Definition of the service node is described in Fig. 2). In addition to the network address information, comprehensive resource information such as network topology, proximity, network load, and status of the service node can be referred to when selecting an optimal service node.

In summary, the service optimization function object (SO-FE) 122 determines the optimal service node to which the content is to be published and also determines the optimal service node to which the content request of the content user is to be processed. To this end, the service optimization function object (SO-FE) 122 can evaluate a service node based on proximity, network topology, availability, etc., For example, information such as status, activity, and performance may be retained and monitored.

The content name resolution function object (CR-FE) 124 manages content position information necessary for content delivery. When issuing a content, the content name resolution functional object (CR-FE) 124 acquires the content identifier and the positional information of the content through interlocking with the content service adjustment function (CSCF) 110, Maintenance and management. Upon receiving a query for a content location from the content delivery service function (CDSF) 130, the content name resolution functional object (CR-FE) 124 locates and returns location information using the identifier information included in the query. In this case, the content name resolution function object (CR-FE <124) may interwork with the service optimization function object (SO-FE) 122 to find an optimal position among a plurality of content position information when necessary.

In summary, the content name resolution function object (CR-FE) 124 manages the content identifier information in association with the content position information, i.e., performs registration, deregistration, and update functions. The content name resolution functional object (CR-FE) 124 uses the content identifier information to find the location information of the content.

The content delivery service function (CDSF) 130 is a function of the data delivery plane of the network, providing an interface for delivering content data to the user 20 or for receiving content from the content provider / origin server 10, And a response operation. More specifically, the content delivery service function (CDSF) 130 enables content delivery from the content provider 10 to the user 20. This content delivery may include some intermediate content delivery steps. For example, downloading content from a content source to a content storage of a service node, content is delivered from the content storage to intermediate service nodes located on a content routing path, and intermediate service nodes caching the content received in its content cache And / or conveying the content from the content storage or cache to the end user 20, and the like. For this, the content delivery service function 130 may include a customer service functional entity (CS-FE) 132 and a content transfer functional entity (CT-FE) 134.

The customer service function object (CS-FE) 132 is associated with the content service coordination function (CSCF) 110 described above. The customer service function object (CS-FE) 132 downloads the content from the first server, that is, the server in which the content provider 10 stores the content, when there is a request to issue the content. To this end, address information of the first server, original name of content, content identifier information, and the like included in the issue request of the content may be used. The customer service function object (CS-FE) 132 manages the downloaded content using the content identifier.

In summary, a customer service function object (CS-FE) 132 downloads content requested to be published from a content provider or a content source. The customer service function object (CS-FE) 132 stores the downloaded contents together with the corresponding issue information. In addition, the customer service function object (CS-FE) 132 delivers content stored in the content storage or cache to the end user 20.

Upon receiving the content request command from the customer service function object (CS-FE) 132, the content transfer function object (CT-FE) 134 extracts the content identifier information from the content request command and, using the extracted content identifier information, It is determined whether or not the corresponding content exists in the content storage and cache of the &lt; RTI ID = 0.0 &gt; The content transfer function object (CT-FE) 134 returns the content if it is determined that the content exists, but if it is determined that there is no content, the content transfer function object (CT-FE) 134 queries the content name resolution function object . The location information of the content means location information of the service node storing the content. In this case, if the location information of the cached contents is used, the query to the content name resolution functional object (CR-FE) 124 may be omitted.

When the content transfer function object (CT-FE) 134 acquires the service node information for transferring the content request together with the location information of the content from the content name resolution functional object (CR-FE) 124, You can know the next forwarding service node to request. In this case, the content transfer function object (CT-FE) 134 transfers the request for the content to the next transfer service node and simultaneously stores the information included in the received content request in a predetermined database, for example, a pending table As shown in FIG. At the next service node, delivery of the content request is performed in the same manner. If the content is found, the requested content is returned.

In summary, a content transfer function object (CT-FE) 134 interacts with a content name resolution functional object (CR-FE) 124 to discover a content location, i.e., storage or cache. The content transfer function object (CT-FE) 134 fetches the content from the local content storage or cache. Also, the content transfer function object (CT-FE) 134 relays and / or caches the content received via the content routing path so that the requested content can be transmitted to the user.

FIG. 2 is an example of implementing the network node apparatus of FIG. 1, and is a diagram showing functions 110, 120, and 130 constituting the network node apparatus 100 as a relation between the control node and service nodes. Referring to FIG. 2, the functions 110, 120 and 130 constituting the network node apparatus 100 can be divided into a control node and a service node, (CSCF) 110 and a content delivery control function (CDCF) 120, and the service node includes a Content Delivery Service Function (CDSF). Hereinafter, each network node will be described.

The service node is an object corresponding to the data transfer plane. The service node may include a storage for storing contents as a physical object and a server for providing application services. These service nodes may include a publication service node and a content service node. The issue service node refers to a service node that downloads the issued content from the origin server (10b). And the content service node refers to a service node directly providing the content requested by the user to the user. The content delivery service function (CDSF) 130 of FIG. 1 may be implemented in a service node, that is, an issue service node and a content service node.

The control node is an object corresponding to the control plane. The control node provides services such as issuance and registration of contents, management of location information, and the like. These control nodes include a content service coordination function (CSCF) 110 and a content delivery control function (CDCF) 120, which may be performed together at the same control node or separately at each control node. FIG. 2 shows a case where a content service coordination function (CSCF) 110 and a content delivery control function (CDCF) 120 are performed together in the same control node.

Next, an operation method of the network node apparatus 100 of FIG. 1 for information-based networking will be described. The operation method of the network node apparatus 100 to be described later includes a content publication procedure for registering a content in an information-centric network, for example, a smart ubiquitous network (SNU), and a content service providing content requested from a user service provisioning procedure.

3 and 4 are diagrams for explaining a content issuing procedure through the network node apparatus 100 of FIG. 1, and FIG. 3 is a diagram for explaining a relationship between functions constituting the network node apparatus 100 in the content issuing process FIG. 4 shows an example of a message flow diagram between functions constituting the network node apparatus 100 in the content issuance process.

Referring to FIG. 3, a content provider (CP) 10a requests publication of a predetermined content to a content service coordination function (CSCF) 110 (publication request). The content service coordination function 110 requests the content delivery control function (CDCF) 120 to register the content requested for publication and also publishes the content to the content delivery service function (CDSF 130) ). Upon receiving the content issuance instruction, the content delivery service function 130 downloads the content from the first server 10b (content downloading) and also registers the identifier of the downloaded content by itself (content ID local registration). As a result, the information of the contents which can be provided by the content delivery service function 130 is updated.

An example of a message flow diagram according to a content issuance procedure based on a correlation between functions constituting such a network node apparatus is shown in Fig.

Referring to FIG. 4, the content provider 10a transmits a publication request message to a content issuing function object (CP-FE) 112 (S201). The issue request message may include location information of a content to be issued, for example, a URL (Uniform Resource Locator) and various metadata related to the content. For example, the metadata may include network identifier information (e.g., IP address) of the initial server of the content, basic information about the content such as the owner, type, size, format, etc. of the content.

Then, the content issuing function object (CP-FE) 112 generates an identifier for content requested to be issued, that is, a content ID (S202). There is no particular limitation on the method for determining the content identifier in the present embodiment, but may be determined based on, for example, the policy of the network. However, the determined content identifier should be unique in the network, and should not be duplicated with the content identifier of other content.

Then, the content publishing function object (CP-FE) 112 transmits a content registration request message to the content name resolution functional object (CR-FE) 124 (S203). Content registration refers to setting the content as a service item. The content registration request message may include location information of the content, for example, a URL, along with the content identifier generated in step S202. All or a part of the metadata of the corresponding content received in step S201 may be included in the content registration request message.

Then, the content name resolution functional object (CR-FE) 124 transmits a publication service node selection request message to the service optimization functional object (SO-FE) 122 (S204). The issuance service node selection request message is a message for requesting selection of a service node (refer to the issuance service node in Fig. 2) to issue the content requested to be issued. The publication service node selection request message may include location information (e.g., URL) and metadata of the content requested to be published.

Then, the service optimization function object (SO-FE) 122 selects an issue service node suitable for issuing the corresponding content in response to the received selection request message (S205). At this time, the service optimization function object (SO-FE) 122 may refer to location information (e.g., URL) and / or metadata of the contents included in the received selection request message. According to the present embodiment, there is no particular limitation on a specific algorithm in which the service optimization function object (SO-FE) 122 selects an issue service node.

Then, the service optimization function object (SO-FE) 122 delivers a publication service node selection response message to the content name resolution functional object (CR-FE) 124 (S206). The publication service node selection response message is a response to the publication service node selection request message in step S204, and includes information on the publication service node selected in step S205. For example, the publication service node selection response message may include location information of the selected publication service node.

The content name resolution function object (CR-FE) 124 uses the location information of the selected service node included in the received publication service node selection response message to update the database under management, for example, the content name resolution information base Base, CRIB) table (S207). Here, the CRIB table is one of the management tables, which is a DB that refers to the location information of the issuance service node with the content identifier, and the name is exemplary. That is, the CRIB table records the mapping relationship between the content identifier and the location information of the service node to which the content is already issued or to be issued soon. For example, the CRIB table is a database listing the content identifier and the location information of the publication service node .

Then, the content name resolution functional object (CR-FE) 124 transmits a content registration response message to the content issuing functional object (CP-FE) 112 (S208). The content registration response message is a message transmitted in response to the content registration request message in step S203. If registration of the content requested to be registered is normally performed in step S201, the content registration response message may include location information of the issue service node selected in step S205.

The content publishing function object (CP-FE) 112 transmits a content publication request message to the customer service function object (CS-FE) 132 of the selected issuing service node (S209). Here, the selected issuance service node can grasp using the location information included in the content content registration response message received in S208. The content issue request message transmitted in this step may include the content identifier and the location information of the server where the content is stored, for example, the URL information of the first server 10b.

The customer service function object (CS-FE) 132 downloads the contents from the first server 10b (S210 and S211). More specifically, the customer service function object (CS-FE) 132 refers to the location information of the received first server 10b and transmits a content downloading request message to the first server 10b (S210) . The customer service function object (CS-FE) 132 receives a content downloading response message in response to the request message (S211). The content download response message received in step S211 may include the content, or the content may be downloaded through the content download process.

Then, the customer service function object (CS-FE) 132 transmits a content ID local registration request message to the content transfer function object (CT-FE) 134 (S212). The content identifier local registration request message is a message requesting registration of the downloaded content in the network in step S211. To this end, the content identifier registration message may include the identifier information of the content downloaded in step S211.

In step S213, the content transfer function object (CT-FE) 134 transmits a content identifier registration response message to the customer service functional object (CS-FE) 132 in response to the registration request message in step S212. Here, after confirming that the service for the content corresponding to the content identifier received through the content identifier local registration request message in step S212 can be provided, the content transfer function object (CT-FE) Can be transmitted.

The customer service functional object (CS-FE) 132 receiving the content identifier registration response message transmits a content publish response message to the content issuing functional object (CP-FE) 112 (S214). This content issue response message is transmitted in response to the content issue request message in step S209. Subsequently, the content publishing function object (CP-FE) 112 transmits a publication response message to the content provider 10a (S215).

5 and 6 are diagrams for explaining a content service provision procedure through the network node apparatus 100 of FIG. 1, and FIG. 5 is a diagram for explaining a function of configuring the network node apparatus 100 FIG. 6 shows an example of a message flow diagram between functions constituting the network node apparatus 100 in the process of providing a content service.

Referring first to FIG. 5, a user 20 sends a content request to a content service coordination function (CSCF) 110. Then, the content service coordination function (CSCF) 110 selects an appropriate service node to provide the content to the user 20 by querying the content delivery control function (CDCF) 120 with an optimal service node . When the user 20 requests the content service node again from the selected content service node received from the content service coordination function (CSCF) 110, the user 20 receives the content service node, more specifically, from the content delivery service function (CDSF) 130 Content can be consumed to provide content consumption. Depending on the implementation, the user 20 may receive the content either directly by the selected content service node or through the service node that received the content request for the first time without sending the content request again.

A message flow diagram according to a content service provision procedure based on a correlation between functions constituting such a network node apparatus is shown in Fig. The content service providing procedure includes a content service procedure for providing a content to a user in response to the content request to the user.

Referring to FIG. 6, the user 20 transmits a content request message to a service request routing functional object (SR-FE) 114 (S301). The content request message may include information (e.g., original name of the content) for specifying the content. The content request message may also include location information of the content, for example, a URL. If the user uses the web service, the content request message may be a HTTP (Hyper Text Transfer Protocol) GET message, which is merely exemplary.

The service request routing function object (SR-FE) 114 obtains the context information of the user 20 from the received content request message and obtains a content ID (S302). The context information of the user may include an IP address of the user 20, location information, and the like. In this step, the content identifier can be obtained using the location information of the content included in the content request message, for example, a URL.

The service request routing function object (SR-FE) 114 transmits a content service node selection request message to the service optimization function object (SO-FE) 122 (S303). The content service node selection request message is a message for requesting the user 20 to select a service node suitable for providing a service for the content. The context information of the user may be included in the content service node selection message.

Then, the service optimization function object (SO-FE) 122 selects a content service node suitable for providing the content to the user 20 (S304). At this time, the service optimization function object (SO-FE) 122 can select a service node based on the context information of the user included in the received selection request message. For example, the service optimization function object (SO-FE) 122 can select a content service node close to the user 20 based on the location information of the user 20. [

Then, the service optimization function object (SO-FE) 122 transmits a content service node selection node message to the service request routing functional object (SR-FE) 114 (S305). The content service node selection response message is transmitted in response to the selection request message in step S303. Therefore, the content service node selection response message may include information that can be connected to the content service node selected in step S304, for example, location information of the content service node.

The service request routing function object (SR-FE) 114 transmits a content request redirection message to the user 20 (S306). The content request redirection message is a message requesting to send a content request message back to the content service node selected in step S304. For example, if the user 20 is using a web service, an HTTP 308 Permanent Redirect message may be used, which is exemplary only. The content request redirection message may include location information of a selected content service node, a content identifier, and the like.

The user 20 having received the content request redirection message transmits the content request message again to the selected content service node (S307). More specifically, the content request message may be sent to a customer service functional object (CS-FE) 132 of the selected content service node. The retransmitted content request message may include at least information for identifying the content, i.e., a content identifier. Here, if the user uses the Web service, the content request message may be a HTTP (Hyper Text Transfer Protocol) GET message, which is merely exemplary.

The customer service function object (CS-FE) 132 of the selected content service node requests the contents to the contents transfer function object (CT-FE) 134 of the corresponding contents service node (S308). The content request in this step may include the content identifier received in step S307. (CT-FE) 134 and a customer service function object (CS-FE) 134 when the content service node receiving the content request from the user 20 has the requested content, , 132 proceed directly to steps S310 and S311 to deliver the requested content to the user. On the other hand, when the requested content service node does not have the content requested by the user, the content transfer function object (CT-FE) 134 transmits the content transfer function object CT-FE (R) And acquires the corresponding content by performing an operation for communicating the requested content (S309).

The content transfer function object (CT-FE) 134 transfers the requested content that the CT-FE 134 has acquired or acquired in step S309 to the CS-FE 132 (S310). The content delivery in this step is transmitted in response to the content request in step S308.

The customer service function object (CS-FE) 132 transmits a content response message to the user 20 (S311). This content response message contains at least the requested content. Here, if the user is using the Web service, the content request message may be an HTTP 200 OK message, which is merely exemplary.

The above description is only an example of the present invention, and the technical idea of the present invention should not be interpreted as being limited by this embodiment. The technical idea of the present invention should be specified only by the invention described in the claims. Therefore, it is apparent to those skilled in the art that the above-described embodiments may be modified and embodied in various forms without departing from the technical spirit of the present invention.

Claims (17)

Upon receiving a content request for a first content from a user, querying and receiving information about a first content service node to process the content request, and also causing the content request to be redirected to the first content service node Content Service Coordination Function (CSCF);
In response to a query from the CSCF that received the content request, selecting a first content service node from among one or more content service nodes holding the first content and notifying the CSCF of the first content service node Control Function, CDCF); And
And a Content Delivery Service Function (CDSF) for transmitting the first content to the user upon receiving the redirected content request. The method according to claim 1,
Wherein the CSCF finds the content identifier of the first content based on the content address information of the first content included in the received content request, and transmits the content identifier to the CDCF in the query. &Lt; / RTI &gt; The method according to claim 1,
Wherein the CSCF identifies the IP address information of the user, the content address information of the first content, and the content identifier from the received content request and includes the content identifier in the query to the CDCF, the CDCF comprising proximity, network topology, And selecting the first content service node as an optimal content service node for processing the content request based on the network resource information including the first content service node and the second content service node. The method according to claim 1,
The CDCF manages a content identifier of each content registered in the network and one or more pieces of content location information corresponding to the content identifier in a predetermined database,
Wherein the CDSF having received the redirected content request transmits the first content to the user using the content location information of the first content obtained by communicating with the CDCF. Device. 5. The method of claim 4,
Wherein the CDSF initiates content routing based on the content identifier of the first content to receive the first content and send the content to the user if the first content is not stored in the storage or cache of the first content service node, To the network node device for information-centric networking. The method according to claim 1,
Wherein the CSCF includes a content service functional entity that handles the content request and also causes the content request to be redirected,
Wherein the CDCF includes a service optimization functional entity for selecting the first content service node among the one or more content service nodes, and a content identifier for each of the content registered in the network and one or more pieces of content location information corresponding thereto A content name resolution functional entity for managing with a predetermined database,
Wherein the CDSF interacts with the customer service functional entity to transmit the first content to the user and the location information of the first content by interacting with the content name resolution functional object, Characterized in that the network node device comprises a content transfer functional entity that is fetched from the storage or cache or routed along the content routing path. The method according to claim 1,
The CSCF, when receiving the issuance request for the second content from the content provider, notifies the first issuance service node, which holds the issuance information of the second content and processes the issuance request received by inquiring the CDCF, Lt; / RTI &gt;
In response to a query from the CSCF that received the issuance request, the CDCF selects the first issuance service node from among one or more issuance service nodes and notifies the CSCF of the first issuance service node. . 8. The method of claim 7,
Wherein the CDSF downloads the second content to be issued from the content provider and stores the second content together with the issuance information when receiving the issuance request of the second content from the CSCF. 8. The method of claim 7,
Wherein the CSCF includes a content publication functional entity that handles the issuance request and generates a content identifier of the second content,
Wherein the CDCF includes a service optimization functional entity for selecting the first issue service node among the one or more issue service nodes, and a content identifier for each of the contents registered in the network and one or more pieces of content position information corresponding thereto A content name resolution functional entity for managing with a predetermined database,
Wherein the CDSF comprises a customer service functional entity for downloading the second content from the content provider and storing downloaded content and issue information. A content service method through a Content Service Coordination Function (CSCF) of a network node device for information-centric networking,
(a) receiving a content request for a first content from a user;
(b) querying a Content Delivery Control Function (CDCF) for information about a first content service node that will process the content request;
(c) receiving information about the first content service node selected by the CDCF from one or more content service nodes holding the first content; And
(d) causing a content delivery service function (CDSF) to redirect the content request to the first content service node to forward the first content to the user, . 11. The method of claim 10,
Wherein the content identifier of the first content is obtained based on the content address information of the first content included in the content request received in the step (b), and the content identifier is included in the query and transmitted to the CDCF Service method. 12. The method of claim 11,
Wherein step (d) comprises the step of requesting the user to redirect the content request for the first content to the first content service node,
Wherein the user receiving the redirect request transmits a content request using the content identifier of the first content to the CDSF. 13. The method of claim 12,
After the step (d), the CDSF, which has received the content request, requests the first content to the CDCF using the content identifier, and the CDCF also obtains the first content from the storage or cache, Route to the CDSF. A content issuing method through a Content Service Coordination Function (CSCF) of a network node apparatus for information-centric networking,
(a) receiving a publication request for a first content from a content provider;
(b) generating a content identifier for the first content;
(c) querying a content delivery control function (CDCF) for information about a first issue node to process the publish request;
(d) receiving information about a first issue service node that will process the issue request selected by the CDCF from one or more issue service nodes; And
(e) sending a publication request for the first content to the CDCF such that a Content Delivery Service Function (CDSF) downloads the first content from the content provider. 15. The method of claim 14,
Wherein the step (c) comprises transmitting to the CDCF a content registration request message including a content identifier of the first content and address information of the content provider,
Wherein the step (d) comprises receiving, from the CDCF, a content registration response message including address information of the first issuance service node. 16. The method of claim 15,
In step (d), a content name resolution functional entity of the CDCF, which has received the content registration request message, transmits a request for issuing an issuance service node to a service optimization functional entity of the CDCF And the service optimizing function object transmits to the content name resolution functional object a publication service node selection response including address information of the first publication service node selected from the one or more publication service nodes. How to issue. 15. The method of claim 14,
(f) receiving a content issue response in response to the content issue request from the CDSF that has registered the downloaded first content.

Images