KR20130085552A

KR20130085552A - Method and apparatus for generation forwarding table, method for providing contents using the same

Info

Publication number: KR20130085552A
Application number: KR1020110138037A
Authority: KR
Inventors: 김주희; 손의승; 백은경
Original assignee: 주식회사 케이티
Priority date: 2011-12-20
Filing date: 2011-12-20
Publication date: 2013-07-30

Abstract

The present invention relates to a method of generating a forwarding table, the method of generating a forwarding table of a node constituting a mobile network, the method comprising: transmitting an information request packet to a neighbor node, the neighbor node corresponding to the information request packet from the neighbor node; Receiving the area information of and the content related information stored in the neighbor node, and updating the forwarding table using the area information of the neighbor node and the content related information. According to the present invention, it is possible to perform priority routing in the area by periodically checking the area information between nodes and updating the path information on the content, and reduce the redundant traffic load between each node and the backhaul constituting the network effectively. Content can be provided to the user.

Description

METHOD AND APPARATUS FOR GENERATION FORWARDING TABLE, METHOD FOR PROVIDING CONTENTS USING THE SAME}

The present invention relates to a method and apparatus for generating a forwarding table, a content providing method using the same, and more particularly, to a method and apparatus for generating a forwarding table of a node constituting a mobile network, and a content providing method using the same.

Recently, as the spread of smart phones and the increase in the use of multimedia contents, wireless data traffic is rapidly increasing, and methods for reducing traffic are being discussed in consideration of the content usage patterns of users.

According to the analysis results of various usage patterns, including IPTV content usage patterns, Paletto's law, where 20% of the content shows 80% of the usage, is also applied to the content usage pattern. For example, during the Olympics or baseball season, many users want to watch live broadcasts of the game, and the main scene videos are often requested to be viewed again. In addition, the frequency of use of a particular popular program is generally higher than the sum of the frequency of use of many non-popular programs.

In connection with this usage pattern, there are methods for improving network efficiency, such as a content centric network, a named data network, and an information centric network.

Instead of using Internet IP addresses, content-centric networks use data names, or data names, to perform data delivery on the network. Nodes (routers) in the network perform routing with data names, store the content data they deliver in their own cache, and distribute the data to nearby consumers who request the data. Therefore, according to the content-oriented network, it is not necessary to repeatedly transmit the same data as the number of users as in the conventional IP-based Internet transmission method.

However, if all routers in the network are all connected to the external Internet (backhaul), when a content consumer connected to the network wants to receive data from a content distributor connected to the external Internet, even if the neighboring routers in the network have the corresponding data, Since there is a request, there is a problem that duplicate traffic still occurs in the backhaul period.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem, and the preferred routing is performed in a randomly configured mobile network, thereby reducing the redundant traffic load between each node constituting the network and the backhaul, which is an upper region (or layer), and effectively The purpose is to provide content.

Another object of the present invention is to provide a method and apparatus for generating a forwarding table capable of performing preferential routing in a region by periodically checking region information between nodes and updating route information regarding contents.

The objects of the present invention are not limited to the above-mentioned objects, and other objects and advantages of the present invention which are not mentioned can be understood by the following description and more clearly understood by the embodiments of the present invention. It will also be readily apparent that the objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.

According to an aspect of the present invention, there is provided a method for providing content to a user terminal using a plurality of nodes constituting a mobile network, the method comprising: receiving a content request packet, the first node corresponding to the content request packet; Determining whether content is stored, and if the content is not stored in the first node, forwarding the content request packet to a second node using a forwarding table of the first node. The forwarding table includes content related information stored in a neighbor node and pace information connected to the neighbor node, and is generated using area information of the neighbor node received from the neighbor node.

The present invention also provides a method of generating a forwarding table for a node constituting a mobile network, the method comprising: transmitting an information request packet to an adjacent node, area information of the neighboring node corresponding to the information request packet from the neighboring node, and the neighboring information; Receiving the content related information stored in the node; updating the forwarding table by using the area information of the adjacent node and the content related information.

In addition, the present invention is a device for generating a forwarding table of a node constituting a mobile network, transmitting an information request packet to a neighbor node, from the neighbor node to the area information and the neighbor node of the neighbor node corresponding to the information request packet; And a processor configured to update the forwarding table by using a packet transceiver configured to receive stored content related information, area information of the adjacent node, and the content related information.

According to the present invention as described above, it is possible to reduce the redundant traffic load between each node and the backhaul constituting the network by effectively performing the preferred routing in the region of the arbitrarily set mobile network and to effectively provide content to the user.

According to the present invention, it is possible to provide a method and apparatus for generating a forwarding table capable of performing preferential routing in an area by periodically checking the area information between nodes and updating path information on content.

1 is a view showing a data flow in a mobile network by a conventional content providing method,
2 is a view showing a data flow in a mobile network by a content providing method according to an embodiment of the present invention;
3 is a flowchart illustrating a content providing method according to an embodiment of the present invention;
4 is a flowchart illustrating a content providing method according to an embodiment of the present invention in more detail.
5 is a block diagram illustrating an apparatus for generating a forwarding table according to an embodiment of the present invention;
6 is a view for explaining an information request packet used for generating a forwarding table of the present invention;
7 is a view for explaining a data packet used for generating a forwarding table of the present invention;
8 is a view showing an embodiment of a forwarding table generated by the method of generating a forwarding table of the present invention;
9 is a flowchart illustrating a method of generating a forwarding table according to an embodiment of the present invention;
10 is a flowchart illustrating a forwarding table update process in detail in a method of generating a forwarding table according to an embodiment of the present invention.

The above and other objects, features, and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings, which are not intended to limit the scope of the present invention. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to denote the same or similar elements.

Hereinafter, a conventional content providing method and a content providing method to which the present invention is applied will be briefly described through data flow in a wireless mesh network divided into regions (or layers). 1 is a diagram illustrating a data flow according to a conventional content providing method, and FIG. 2 is a diagram showing a data flow according to a content providing method according to an embodiment of the present invention. As shown in the figure, it is assumed that the wireless mesh network is composed of area0 (110), which is the external Internet, and n mesh networks (area1, area 2, ..., area n) serving as other access sections. In this case, the mesh network may be composed of two or more nodes, which are divided into one area, and each node is connected to an external Internet (backhaul), which is an upper area. As shown in the figure, an area is a network composed of nodes covering a specific area or a specific range, and may have a hierarchical structure between areas, such as area 0 and other access section areas. In FIG. 1 and FIG. 2, the arrow indicated by the dotted line indicates the flow of the content request packet, and the arrow indicated by the solid line indicates the flow of the content.

1 and 2, first, the client 10 requests content to the node 101, and the node 101 delivers the content received from the content server 50 to the client 10, and transmits the content to the node 10. 101 is stored (cached) in the cache.

Then, when another client 20 requests the same content to the node 103 of the same area as the node 101, according to the conventional content providing method, since all nodes are connected to the external Internet 110, the node ( 103 may request content from the external node 110 even if the content is stored in the neighbor node 101. Therefore, there is a problem that duplicate traffic still occurs in the backhaul period.

However, according to the content providing method of the present invention shown in FIG. 2, when the client 20 requests the same content to the node 103, the node 103 stores the corresponding content among the nodes of the same area 100. The content request packet is forwarded to 101. That is, the node 103 can receive the content stored in the adjacent node 101, not the content server 50, and provide the content to the client 20, thereby reducing traffic distribution.

3 is a flowchart illustrating a content providing method according to an embodiment of the present invention. Referring to FIG. 3, when the first node constituting the mesh network receives the content request packet (S310), the first node determines whether content corresponding to the content request packet is stored in the first node (S330). As a result, when the content corresponding to the content request packet is not stored in the first node, the content request packet is transmitted to the second node using the forwarding table of the first node (S350). Here, the second node refers to a node connected to a face corresponding to the content request packet among adjacent nodes of the first node.

Here, the "forwarding table" used for content request packet delivery may be used as the terms "forwarding information base" (FIB), "information delivery base", and "delivery table". The forwarding table refers to a data structure that manages a path through which a content request packet is delivered. The forwarding table can be set statically, and can be dynamically constructed using existing routing protocols such as OSPF and BGP. More specifically, the forwarding table of the present invention includes content related information stored in the neighbor node and pace information connected to the neighbor node, and is generated using area information of the neighbor node received from the neighbor node.

Here, the "adjacent node" is a node adjacent to a node including a forwarding table, and means nodes that are one hop away from a node as a reference, and "content related information" is a prefix information or content of the content. Refers to a variable length identifier of a hierarchical structure.

"Face" means the interface of a node that couples to an application or network. The face may be based on hardware or software, and request packets, data packets, and content packets are received and forwarded through the face.

"Area information of a node" is area information of a mesh network including a corresponding node. In the present invention, a method of distinguishing areas is not particularly limited. In addition, in the present invention, it is assumed that each node constituting the mesh network knows its own area. In addition, as used herein, the term "region" or "network region" refers to a specific region or range determined according to a user setting as described above. Each region includes one or more nodes and may have a hierarchical structure. The area of the mesh network may be set in various ways as needed. For example, when a WiFi AP is installed in a subway, two APs installed in a quantity may be set to be included in one mesh network area, and one train may be set. All APs included in the may be set to one mesh network area.

That is, unlike the conventional content delivery method, the present invention generates the forwarding table using the area information of the neighbor node. Therefore, by forwarding the content request packet using the forwarding table, priority routing can be performed in a specific area, thereby reducing the redundant traffic load between the node and the backhaul.

If it is determined in step S330 that the content corresponding to the content request packet is stored in the first node, the content is delivered to the pace at which the content request packet is received (S370). In other words, each node forwards the content to the face that receives the content request packet, and thus reverses the delivery path of the content request packet so that the client who requested the content can receive the content.

4 is a flowchart illustrating a content providing method according to an embodiment of the present invention in more detail. 4 shows a processing procedure in each node constituting the wireless mesh network.

Referring to FIG. 4, the first node constituting the wireless mesh network first receives a content request packet or content (S410). It is determined whether the received packet is the content request packet or the content (S430). If the received packet is the content request packet, it is checked whether the content corresponding to the content request packet is stored in the content storage CS (S450). . If the content is stored in the content storage, the content is delivered to the face receiving the content request packet (S455). If the corresponding content is not stored in the content repository, it is checked whether the content request packet is registered in the PIT (Pending Interest Table) (S460). Here, the PIT refers to a data structure for identifying a content request packet that has been received at the first node based on content related information such as content prefix information of the content. The PIT includes a content name included in the content request packet and pace information for receiving the content request packet. The first node may determine where and how to deliver the content with reference to the PIT. If the content request packet information is registered in the PIT, this means that the content has not been delivered yet. If a content request packet received in the PIT is not registered, the first node registers it (S461) and searches for a forwarding table (S463). In operation S465, the content request packet may be delivered at a pace at which content related information is matched in the forwarding table. If there is a response from the second node that receives the content request packet from the first node, that is, the content is received, the content is delivered to the pace at which the content request packet is received using the PIT (S455). If there is no response from the second node, it terminates or searches the forwarding table again (S463) and delivers the content request packet to the next path (S465).

If the packet received by the first node is content, it is searched whether or not the content is registered in the PIT (S470), and the content is delivered to the face matched in the PIT (S473). The received content is stored in the content storage of the first node (S475). The process S475 refers to the caching process described with reference to FIGS. 1 and 2, which stores content in a cache of the first node.

If the content is not registered in the PIT of the first node, since the pace to be delivered does not exist, the content may be discarded (S477), and although not shown in the drawing, the content may be stored in the content repository.

Each node constituting the wireless mesh network may provide content requested by the client to the client by performing the above process.

The above-described forwarding table used in step S350 of FIG. 3 and step S463 of FIG. 4 is generated separately from the content request packet and the flow of the content so that priority routing in the region can be made. Hereinafter, FIGS. 5 through 8 will be described. An apparatus for generating a forwarding table according to an embodiment of the present invention will be described.

5 is a block diagram illustrating an apparatus for generating a forwarding table according to an embodiment of the present invention. The apparatus for generating a forwarding table according to an embodiment of the present invention may include a packet transceiver 510, a processor 530, and a storage unit 550 configured to store a table.

The packet transceiver 510 transmits an information request packet to an adjacent node, and receives area information of the neighbor node corresponding to the information request packet and content related information stored in the neighbor node from the neighbor node. The packet transceiver 510 may be configured as a face connected to an adjacent node. For example, when the forwarding table generating apparatus illustrated in FIG. 5 is referred to as node 0, node 1, which is an adjacent node, may be connected to face 0, node 2 to face 1, and node 3 to face N. FIG. The packet transceiver 510 may periodically update the forwarding table by periodically transmitting an information request packet to an adjacent node.

Herein, the "information request packet" is a packet for requesting information of an adjacent node to generate a forwarding table, and may have the same form as the content request packet. That is, the apparatus 500 for generating a forwarding table according to an embodiment of the present invention may request information of an adjacent node using an interest packet used in a content-oriented technology.

Referring to FIG. 6, the information request packet may include a content name field 610 and a selector field 650. The content name field 610 of the information request packet may include the name of the requested information. For example, when requesting area information, / area_info is described in the content name. In the selector field 650, an item not described in the content name may be described in detail. In addition, since the information request packet is a packet transmitted periodically to update the forwarding table, the scope field value of the selector field 650 can be set to 2 so that the information request packet can be delivered to the next hop node.

In one embodiment, when receiving the information request packet from the packet transceiver 510 of the node 0, neighboring nodes (nodes 1, 2, 3) in response to the information request packet, its own area information corresponding to the information request packet and The content related information stored therein is transmitted to the packet transceiver unit 510 of the node 0.

In this case, the packet transceiver 510 may receive the area information of the neighbor node and the content related information stored in the neighbor node in the form of a data packet. The data packet shown in FIG. 7 is an embodiment of a data packet received by the packet transceiver 510. Referring to FIG. 7, the data packet may include the content name field 710 as in the above-described information request packet, and may include the data fields 730 and 750. Although not shown in the figure, the data packet may further include a signature and a signed information field.

As an example, assuming that the data packet of FIG. 7 is transmitted from node 2 of FIG. 5 to node 0, after receiving an information request packet from node 0, node 2 checks its area information. After the node 2 checks its own content related information such as prefix information of the content stored in the content repository, the node 2 includes the area information 753 and the content related information 757 in the data field 750 of the data packet. Send.

Referring to FIG. 7, the wireless mesh network area of node 2 is area 1, and the prefix information of the content stored in node 2 is "/abcd.com/123/" and "/patent.com/". In the present embodiment, only Node 2 is taken as an example, but each adjacent node that receives the information request packet from Node 0 may transmit its area information and content related information to Node 0 in the form of a data packet.

The longer the content-related information transmitted in the response of the information request packet is, the larger the forwarding table size may be, so it can be adjusted to an appropriate depth. The face information of the forwarding table may be a plurality of lists, and the forwarding table generating apparatus 500 may transmit a plurality of information request packets simultaneously at various paces.

The processor 530 updates the forwarding table using the area information and the content related information of the neighbor node received from the neighbor node. More specifically, the processor 530 may include an analyzer 535 and a processor 537.

The analyzer 535 analyzes the received area information of the adjacent node. The processor 537 adds content related information and face information connected to the neighboring node to the forwarding table when the region of the node corresponding to the analysis result of the analyzer 535 matches the region of the neighboring node.

In the forwarding table of FIG. 8, assuming that "/abcd.com" of entry 3 is a previously registered entry, entries 1 and 2 are updated using area information and content related information received from node 2. . In the forwarding table, "/abcd.com/123/" and "/patent.com/", which are content related information of Node 2, are added, and "1", which is face information connected to Node 2, is added. The forwarding table can be updated by adding priority to recently received information. However, as described above, the processor 537 may add the information of the neighbor node to the forwarding table only when the region of the node and the region of the neighbor node match.

In an embodiment, if the area of node 0 is area 1 and node 1 connected to face 0 is a node of a backhaul (area 0, see FIGS. 1 and 2), node 1 is an adjacent node of node 0, so node 0 is node 1 Sends an information request packet to node 1 and receives a corresponding data packet from node 1. However, since the area of node 1 is area 0 and is different from that of node 0, node 0 does not update node 1's prefix information in its forwarding table. As a result, the forwarding table of node 0 preferentially includes information on neighboring nodes existing in the same area as node 0, so that node 0 may preferentially route nodes in the same area as itself.

The storage 550 may include a content storage 551, a PIT 553, and a forwarding table 557, and the description of each table will be omitted.

9 is a flowchart illustrating a method of generating a forwarding table according to an embodiment of the present invention. Referring to FIG. 9, first, an information request packet is transmitted to an adjacent node (node B) (S910). The neighbor node checks 920 the area information and the content storage of the neighbor node in response to the information request packet. The neighbor node generates a data packet including region information and content related information (925). The node (node A) generating the forwarding table receives the area information of the neighboring node corresponding to the information request packet and the content related information stored in the neighboring node from the neighboring node (S930). The forwarding table is updated using area information and content related information of an adjacent node (S950). As described above, according to the present invention, the forwarding table can be updated by periodically checking the content related information stored in the neighbor node.

10 is a flowchart illustrating a forwarding table update process in detail in a method of generating a forwarding table according to an embodiment of the present invention. Referring to FIG. 10, area information of an adjacent node is analyzed (S1010), and it is determined whether an area of a node and an area of an adjacent node coincide (S1030). If the area of the node matches that of the node as the result of the analysis, the content related information of the node and the pace information connected to the node are added to the forwarding table (S1050). If the area of the node does not match the area of the adjacent node as a result of the analysis, the relevant node related information may be discarded (S1070). Although not shown in the drawing, when the area of the node and the neighboring node do not match, content related information and face information of the corresponding neighboring node may be added as a priority of the forwarding table.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, But the present invention is not limited thereto.

Claims

In the method for providing content to a user terminal using a plurality of nodes constituting a mobile network,
Receiving a content request packet;
Determining whether content corresponding to the content request packet is stored in a first node;
If the content is not stored in the first node as a result of the determination, forwarding the content request packet to a second node using a forwarding table of the first node,
The forwarding table is,
And content related information stored in an adjacent node and pace information connected to the adjacent node, wherein the content providing method is generated using area information of the adjacent node received from the adjacent node.

The method of claim 1,
The forwarding table is,
The area information of the adjacent node is analyzed and updated when the area of the first node coincides with the area of the adjacent node.
How content is delivered.

The method of claim 1,
If the content is stored in the first node as a result of the check,
Delivering the content to the face that received the content request packet;
Content providing method further comprising.

In the method of generating a forwarding table of the nodes constituting the mobile network,
Sending an information request packet to a neighbor node;
Receiving area information of the neighbor node corresponding to the information request packet and content related information stored in the neighbor node from the neighbor node;
Updating the forwarding table using area information of the neighbor node and the content related information;
How to create a forwarding table comprising a.

5. The method of claim 4,
Updating the forwarding table,
Analyzing the area information;
Adding the content related information and face information connected to the neighboring node to the forwarding table when the region of the node and the region of the neighboring node are identical as a result of the analysis;
How to create a forwarding table comprising a.

An apparatus for generating a forwarding table of nodes constituting a mobile network,
A packet transmission / reception unit configured to transmit an information request packet to a neighbor node, and receive area information of the neighbor node corresponding to the information request packet and content related information stored in the neighbor node from the neighbor node;
A processor for updating the forwarding table using area information of the neighbor node and the content related information;
Forwarding table generation device comprising a.

The method according to claim 6,
The processor comprising:
An analysis unit analyzing the area information;
A processing unit for adding the content related information and the face information connected to the neighboring node to the forwarding table when the region of the node and the region of the neighboring node match with each other as a result of the analysis;
Forwarding table generation device comprising a.