WO2017105056A1

WO2017105056A1 - Content-centric network router, and method for transmitting content by means of same

Info

Publication number: WO2017105056A1
Application number: PCT/KR2016/014580
Authority: WO
Inventors: 홍충선; 키타; 이두호
Original assignee: 경희대학교 산학협력단
Priority date: 2015-12-16
Filing date: 2016-12-13
Publication date: 2017-06-22

Abstract

The present invention relates to a content-centric network router, the router comprising: a transceiver for transmitting and receiving one or more from among a content request message and a content response message; and a pre-fetching module for determining the popularity of the xzxzcontent data requested by the content request message, and on the basis of the popularity, deciding whether or not to pre-fetch the content data, and if the decision is to pre-fetch, then generating a message requesting the next content data, the content data following said content data.

Description

Router in Content-oriented Network and Contents Transmission Method Using the Same

The present invention relates to a router of a content-centric network, and a content transmission method using the same, and more particularly, to receive a content request message from a mobile terminal, and to determine the popularity of the content requested from the user, thereby obtaining highly popular content data. It relates to a method of prefetching.

Recently, the number of consumers who watch video through the Internet is increasing rapidly, and a Content Centric Network (CCN) has been proposed in order to cope with the increase in traffic caused by the increase in demand.

The content-oriented network is a structure of requesting and providing a service based on a content name instead of a structure of requesting and providing a service in a 1: 1 structure using a conventional IP address.

The user terminal connects to any one of a plurality of routers provided in the network, and transmits a content request message to the access router. The access router extracts the request content identifier from the content request message, and determines whether the request content is stored and registered in the access router based on the request content identifier.

If there is no request content in the access router, the access router transmits the content request message to the neighbor router of the network by flooding, and the neighbor router or server providing the request content that stores and registers the request content among the neighbor routers. The core router connected to the terminal provides the requested contents to the mobile terminal in the reverse order of receiving the requested contents message.

In such a content-centric network, since a mobile terminal transmits a content request message through a plurality of routers and receives a content, a long time delay occurs when a user requests a content and receives the requested content.

The present invention provides a router of a content-centric network, which determines the popularity of a content requested by a user and prefetches the next content data of the requested content before the user requests, thereby allowing the user to receive the content quickly. It is to provide a content transmission method using the same.

The router for a content-oriented network according to an embodiment of the present invention determines the popularity of the content request message, the transceiver for transmitting and receiving one or more of the content response message, and the content data requested from the content request message, the popularity The prefetching module determines whether to proceed with prefetching of the content data, and generates a message for requesting next content data of the content data when the prefetching process is determined.

The prefetching module counts the requested number of times based on the requested content identifier included in the content request message, and when the sum of the number of requests of the content data exceeds a predetermined threshold, the requested content data. It may include a determination unit that determines that the popularity is high.

The determination unit, if the popularity of the requested content data is high, the prefetching of the content data, the prefetching module, the pre-fetching block further comprises a interest generation unit for generating a message for requesting the next content data of the content data can do.

The apparatus may further include a storage unit for storing the content data, and a storage management unit for determining whether to store the content data in the storage unit.

The storage management unit may refer to a pending interest table (PIT) in which information for determining whether to store the content data in the storage unit is recorded according to the popularity of the content data. You can decide whether to save it.

The storage management unit stores the content data in the most recently used location when there is a free space in the storage, and stores the data of the last used location when there is no free space in the storage. Delete and store the content data in the most recently used location.

According to an embodiment of the present invention, a method for transmitting a content request message by one or more routers among a plurality of routers in a network consisting of a mobile terminal and a plurality of routers may include receiving a content request message from an adjacent lower router or a mobile terminal. Determining the popularity of the requested content data from the content request message; determining whether to prefetch the content data according to the popularity; and if the prefetching process is determined, the requested content data. Generating a message requesting Next content data of the message, and transmitting the message requesting next content data to an adjacent upper router.

The determining of the popularity may include: counting a requested number of times based on a requested content identifier included in the content request message; and wherein a sum of the number of requests of the content data for a predetermined time exceeds a predetermined threshold. In this case, the method may include determining that the requested content data has a high popularity.

Determining whether the requested content data is stored in a router from the content request message, and if the requested content data is not stored in the router, sending the content request message to the adjacent higher router. Can be.

In the generating of the message for requesting the next content data, if the requested content data is the last data of the content, the message for requesting the next content data may not be generated.

A method for storing content data in any one or more routers among a plurality of routers in a network consisting of a mobile terminal and a plurality of routers, according to an embodiment of the present invention, may include receiving a content response message including content data from an adjacent upper router. Determining whether to store the content data in a storage unit according to popularity, determining whether the storage unit is empty, or, if there is empty space in the storage unit, in a location most recently used. Storing the content data, and if there is no empty space in the storage unit, deleting the data of the last used position of the storage unit and storing the content data in the most recently used position.

The determining of whether to store the content data in the storage unit may include: a pending interest table (PIT) in which information for determining whether to store the content data in the storage unit is recorded according to the popularity of the content data. Can be determined by reference.

According to an embodiment of the present invention, a method for transmitting content by one or more routers among a plurality of routers in a network consisting of a mobile terminal and a plurality of routers includes: receiving a content request message from an adjacent lower router or a mobile terminal; Determining a popularity of the requested content data from a content request message; generating a message requesting next content data of the requested content data if the popularity is high, and transmitting the message to a next higher router; Receiving a content response message including content data from a router, and determining whether to store the content data in a storage unit according to popularity.

The determining of the popularity may include: counting a requested number of times based on a requested content identifier included in the content request message, and a sum of the number of requests of the content data for a predetermined time exceeds a predetermined threshold. In this case, the method may include determining that the requested content data has a high popularity.

According to an embodiment of the present invention, users can receive content without delay by prefetching the content of the highly popular content before the user's request in advance.

According to an embodiment of the present invention, a cache pollution problem in a router may be reduced in a content-centric network.

1 is a functional block diagram illustrating a content-centric network according to an embodiment of the present invention.

2 is a diagram for explaining prefetching.

3 is a functional block diagram illustrating a router of a content-centric network according to the present invention.

4 is a functional block diagram illustrating a router of a content-centric network according to the flow of a content request message in an embodiment of the present invention.

5 is a flowchart illustrating a method of determining, by the determining unit of the content-oriented network, whether to proceed with prefetching according to the present invention.

6 is a flowchart illustrating a process of prefetching performed by a router of a content-oriented network according to the present invention.

7 is a flowchart illustrating a method of determining whether or not a router of a content-centric network stores content data according to the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

Throughout the specification and claims, when a portion is said to "include" any component, it means that it can further include other components, except to exclude other components unless specifically stated otherwise.

A content-oriented network according to an embodiment of the present invention will now be described in detail with reference to the drawings. 1 is a functional block diagram illustrating a content-centric network according to the present invention.

Referring to FIG. 1, a content-oriented network according to the present invention includes a network 20 having a plurality of

routers

20A, 20B, 20C, and 20D, a mobile terminal 10 connected to a network 20, and a server. It consists of 30.

The mobile terminal 10 connects to any one of the plurality of

routers

20A, 20B, 20C, and 20D provided in the network 20 and connects to the connection router 20A, and requests content from the access router 20A. Send a content request message (CR). The access router 20A extracts the request content identifier from the content request message CR, and determines whether the requested content is stored and registered in the access router 20A based on the request content identifier.

If the requested content does not exist in the access router 20A, the access router 20A transmits the content request message to the neighboring router 20B of the network 20 in a flooded manner and stores and registers the requested content in the router. Core router 20D, which is connected to

adjacent routers

20B and 20C or servers 300 that provide the requested content, includes a content response including the requested content data in a reverse direction of receiving the content request message CR. The message CT is provided to the mobile terminal 10.

In this embodiment, any one or more of the plurality of

routers

20A, 20B, 20C, and 20D extract the content identifier from the content request message (CR) received from the mobile terminal 10 or the adjacent router, and the popularity of the requested content. Judge. The popularity of the content refers to the frequency of requests for certain specific content in the plurality of mobile terminals 10. In this embodiment, the router may determine the popularity of the content by counting the frequency of the content request in real time or at regular time intervals. When the access router determines that the content requested by the mobile terminal 10 is highly popular, the access router generates a content request message (CR) for requesting next content data of the requested content, and the adjacent router or server 30 By sending to a core router connected to the pre-fetch, the content data is prefetched before receiving a message requesting the next content data from the user.

2 is a diagram for explaining prefetching. Prefetching means calling a part of the content data in advance in the router 200 before the user requests. Referring to FIG. 2, when a request message for the i (i = 0,1,2) th data is received, a request message for the i + m (m is a prefetching range) th data is generated and the i + m th This means receiving data in advance and storing it in the router. At this time, the range (m) of prefetching can be freely adjusted according to the storage space in the router.

According to an embodiment of the present invention, the router of the content-centric network determines the requested content popularity, and if it is determined that the content popularity is high, a message for requesting next content data of the content data requested by the user before the user's request is sent. It is possible to transmit content data without delay to the users by generating and transmitting to the adjacent upper router and receiving the next content data from the upper router before the user's request in advance.

In this case, the router of the content-centric network according to an embodiment of the present invention can reduce the cache pollution problem in the router 200 by selecting highly popular content data instead of patching all the contents and prefetching only the content data. have.

The network 20 consists of a plurality of routers 200, each of which transmits and receives messages or content data with adjacent routers. Referring to Figure 3 in more detail, in the content-centric network according to this embodiment any one of the router 200 is a receiver 210, prefetching module 220, storage unit 230, storage management unit 240 And a transmitter 250.

The receiver 210 receives a content request message for requesting specific content data from the mobile terminal 10 or a lower router adjacent to the mobile terminal 10, or receives a core router or a core router connected to the server 30. The content response message including the content data may be received from the upper router.

The prefetching module 220 determines the popularity of the content from the content request message (CR) received by the receiver 210 and determines whether to prefetch the content according to the popularity. The determination unit 221 and the interest It may include a generator 222. The determination unit 221 extracts the requested content identifier from the content request message CR, determines the popularity of the requested content based on the content, and determines whether to prefetch the content according to the popularity of the requested content. The interest generation unit 222 may generate a content request message for requesting next content data of the requested content when the determination unit 221 determines the prefetching progress of the content.

The storage unit 230 stores content data received from a core router connected to the server 30 or an upper router adjacent to the core router, and caches the content data (comparatively short time) or stores (comparatively long time). )can do.

The storage manager 240 determines whether to store the content data received by the receiver 210 in the storage 230 according to the usage capacity of the storage 230.

The transmitter 250 transmits a content request message to a neighboring upper router or a core router connected to the server 30, or transmits a content response message including content data to the neighboring lower router or the mobile terminal 10.

Meanwhile, in the present embodiment, the router 200 may further include a pending interest table (PIT) 260 and a forwarding information base (FIB) 270.

Pending interest table 260 is an arbitrary data structure used to identify and record pending content request message (CR), forwarding information base 270 is a content request message (CR) and content data is received and delivered Any data structure used to associate an interface with content data.

Referring to FIG. 4, the content request message CR received by the receiver 210 is transmitted to the determiner 221. The determiner 221 determines the popularity of the requested content from the content request message CR received by the receiver 210, and determines whether to prefetch the requested content. When the prefetching process is determined, the interest generation unit 222 generates a content request message CR requesting the next content data of the requested content. The router 200 extracts prefetch bit (PB) information for determining whether to store content data from the content request message (CR) in the storage unit 230 and stores the prefetch bit (PB) information in the pending interest table 260. Can record The next request message CR generated by the interest generation unit 222 is transmitted to the core router connected to the upper router or the server 30 via the forwarding information base 270 and the transmitter 250.

5 is a flowchart illustrating a method for determining whether pre-fetching is performed by a router of a content-oriented network according to the present invention.

Referring to FIG. 5, the router 200 receiving the content request message CR from the plurality of mobile terminals 10 requests the content based on the request content identifier included in the content request message CR. The number is counted (S510).

Next, it is determined whether the sum of the number of contents counted in real time or at a predetermined time interval exceeds a predetermined threshold (S520).

When the sum of the requested content numbers exceeds a predetermined threshold, the popularity of the requested content is determined to be high and prefetching for calling the next content data is performed in advance (S530).

On the other hand, if the sum of the requested content numbers does not exceed a predetermined threshold, the router 200 determines that the popularity of the requested content is low, does not proceed with prefetching, but determines whether the requested content data is stored in the router. (S540).

When the requested content data is stored in the router, the content response message including the stored content data is transmitted to the lower router or the mobile terminal 10 (S550).

If the request content data is not stored in the router, the content request message is transmitted to the upper router (S560).

Referring to FIG. 6 in more detail, when prefetching is started, the router 200 extracts a request content identifier from a content request message CR, and the requested content data is stored based on the request content identifier. It is determined whether the stored in (S610).

If it is determined that the requested content data is not stored in the storage unit 230, the router 200 transmits a content request message CR to a higher router (S620), and then receives the content data received by the receiving unit 210. The prefetch bit PB in the pending table 260 may be written as 0 so as not to be stored in the storage 230.

Then, a content request message (CR) is generated for requesting the next content data of the requested content, and the content request message (CR) is transmitted to the upper router (S630). Then, when the next content data is received, the next content data is stored in the storage unit 230. The prefetch bit PB in the pending table 260 can be written as 1 to store.

On the other hand, if it is determined that the requested content data is stored in the storage unit 230, the prefetch in the pending table 260 so as not to duplicately store the content data received from the upper router in the storage unit 230. Bit PB can be written as zero.

In addition, when it is determined that the requested content data is stored in the storage 230, the router 200 determines whether the content data is the last content data based on the requested content identifier (S640). If the content data is the last content data, since there is no next content data to perform prefetching, it ends without generating a content request message requesting the next content data (S650).

If the content data is not the last content data, the router 200 generates a message for requesting the next content data and delivers the message to the upper router (S630), so that the next content data is previously received even if a content request message is not received from the user. After the request, after receiving the next content data, the prefetch bit PB in the pending table 260 may be recorded as 1 to store the next content data in the storage 230.

Referring to FIG. 7 in more detail, the receiver 210 receives a content response message CP including content data from an upper router (S610).

Then, the content response message CP including the content data is transmitted to the lower router or the mobile terminal 10, thereby transmitting request information to the user (S620).

At this time, the storage manager 240 checks the pre-fetch bit (PB) recorded in the pending table 260 by referring to the pending table 260 (S630). When the prefetch bit PB is 1, the router 200 stores the content data in the storage 230.

In more detail, it is determined whether the space of the storage unit 230 is empty (S640), and if there is an empty space in the storage unit 230, it is received at the most recently used position of the storage unit 230. The content data is stored (S650).

If there is no empty space in the storage unit 230, the data of the last used position of the storage unit 230 is deleted, and the content data is stored in the most recently used position (S660). If the prefetch bit PB is 0, the storage unit 230 ends without storing the content data.

An embodiment of the present invention is not implemented only through the above-described apparatus and / or method, but may be implemented through a program for realizing a function corresponding to the configuration of the embodiment of the present invention, a recording medium on which the program is recorded, and the like. Such implementations may be readily implemented by those skilled in the art from the description of the above-described embodiments.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of the operator using the basic concepts of the present invention as defined in the following claims are also provided. It belongs to the scope of rights.

Claims

As a router in a content-centric network,

Transmitting and receiving unit for transmitting and receiving any one or more of the content request message, the content response message, and

Determine the popularity of the requested content data from the content request message, determine whether to prefetch the content data according to the popularity, and if the prefetching process is determined, next content data of the content data. Router comprising a prefetching module for generating a message requesting.
In claim 1,

The prefetching module,

Counting the requested number of times based on the requested content identifier included in the content request message, and determining that the popularity of the requested content data is high when the sum of the number of requests of the content data exceeds a predetermined threshold. Router including a decision unit.
In claim 2,

The determining unit, if the popularity of the requested content data is high, prefetching the content data,

The prefetching module may further include an interest generation unit configured to generate a message for requesting next content data of the content data.
In claim 1,

A storage unit for storing the content data, and

And a storage management unit to determine whether to store the content data in the storage unit.
In claim 4,

The storage management unit,

A router for determining whether to store the content data in the storage with reference to a pending interest table in which information for determining whether to store the content data in the storage is recorded according to the popularity of the content data. .
In claim 4,

The storage management unit,

If there is an empty space in the storage unit, the content data is stored in the most recently used location,

And when there is no empty space in the storage unit, deletes the data of the last used location and stores the content data in the most recently used location.
A method of transmitting a message for requesting content by one or more routers among a plurality of routers in a network consisting of a mobile terminal and a plurality of routers,

Receiving a content request message from an adjacent lower router or mobile terminal,

Determining the popularity of the requested content data from the content request message;

Determining whether to proceed with prefetching of the content data according to the popularity;

Generating a message requesting next content data of the requested content data when the prefetching process is determined, and

And sending a message requesting the next content data to an adjacent upper router.
In claim 7,

Determining the popularity,

Counting the requested number of times based on the requested content identifier included in the content request message, and

And determining the popularity of the requested content data when the sum of the number of requests of the content data for a predetermined time exceeds a predetermined threshold.
In claim 7,

Determining from the content request message whether the requested content data is stored in a router, and if the requested content data is not stored in the router, sending the content request message to the adjacent higher router. How to send a message.
In claim 9,

Generating the message for requesting the next content data,

And if the requested content data is the last data of the content, do not generate a message requesting the next content data.
A method of storing content data in one or more routers among a plurality of routers in a mobile terminal and a network composed of a plurality of routers,

Receiving a content response message containing content data from an adjacent upper router,

Determining whether to store the content data in a storage unit according to popularity;

Determining whether the storage of the storage unit is empty;

Storing the content data in the most recently used location of the storage unit when there is an empty space in the storage unit, and

If there is no empty space in the storage unit, deleting the data of the last used position of the storage unit and storing the content data in the most recently used position

Content data storage method comprising a.
In claim 11,

Determining whether to store the content data in the storage unit,

And a pending interest table (PIT) in which information for determining whether to store the content data in the storage unit is recorded according to the popularity of the content data.
A method for transmitting content by one or more routers among a plurality of routers in a mobile terminal and a network consisting of a plurality of routers,

Receiving a content request message from an adjacent lower router or mobile terminal,

Determining the popularity of the requested content data from the content request message;

Generating a message requesting next content data of the requested content data if the popularity is high, and transmitting the message to a next higher router;

Receiving a content response message containing content data from an adjacent upper router, and

Determining whether to store the content data in a storage unit according to popularity.
In claim 13,

Determining the popularity,

Counting the requested number of times based on the requested content identifier included in the content request message, and

And determining the popularity of the requested content data when the sum of the number of requests of the content data for a predetermined time exceeds a predetermined threshold.
In claim 13,

Determining from the content request message whether the requested content data is stored in a router, and if the requested content data is not stored in the router, sending the content request message to the adjacent higher router. How to transfer content.
In claim 13,

Generating the message for requesting the next content data,

And if the requested content data is the last data of the content, do not generate a message requesting the next content data.