JP2007201919A - Traffic engineering multicast distribution method, system, nodes, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To set a path for transmitting band information for a user to view a content in a communication network, and for securing a band by the transmitted band information in the communication network, and for making contents with an identical content ID in the same route. <P>SOLUTION: In a node apparatus, a multicast tree setting request message including the content ID is transmitted when a multicast group participation message is received from a terminal device of the user. In the node apparatus connected to a content transmitting apparatus, a path calculation means for calculating such a path that a plurality of LSPs set for distribution may become identical paths, and a band security startup message including the calculated path and the band information is created and transmitted to a downstream node when the multicast tree setting request message is received. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a traffic engineering multicast distribution method, system, node, and program, and in particular, transmits band information for viewing content from a user terminal device, and sets a band based on band information received by a communication network. The present invention relates to a traffic engineering multicast distribution method, system, node, and program to be secured.

  Conventional protocols for multicast distribution include PIM (Protocol Independent Multicast) (RFC2362), IGMP (Internet Group Management Protocol) (RFC2236), and the like.

  However, these protocols provide a function for constructing a delivery route, and management of the bandwidth of the delivery route is not considered. For this reason, when a distribution route is configured by applying these protocols, it is possible that a stream of a bandwidth or higher is transferred to the line that is the distribution route. When a stream exceeding the bandwidth is transferred, packet loss or the like occurs, and the quality of content deteriorates.

  Further, RSVP (Resource Reservation Protocol) (RFC2205) is available as a protocol for reserving bandwidth. Since RSVP is originally a protocol that is applied to secure a band between a sender host and a receiver host, studies are underway to apply it when RSVP configures a distribution route. However, in the examination here, the route of the distribution route is set individually for each multicast group address, and the content data of all layers effective in the case of layered content cannot be made the same route. In addition, the setting of the bandwidth of the distribution path is performed based on data that the system has in advance, and cannot be set based on the bandwidth information transmitted from the user side (for example, Non-patent document 1).

FIG. 13 is a diagram for explaining a conventional method for setting a route of a distribution path.
FIG. 2A shows that a conventional system uses a backbone network 1, nodes 7a, 7b, 7c, 7d and 7d constituting the backbone network 1, a program guide server device 3, access networks 4a and 4b, A user terminal device 8 and a content transmission device 6.

  The backbone network 1 is an MPLS (Multi Protocol Label Switching) network, that is, the node devices 7a to 7e are node devices having an MPLS function. The program guide server 3 is a server device that distributes content information distributed by the content transmission device 6 to the terminal device 8 of the user, and is connected to the backbone network 1. The access networks 4a and 4b are connected to the backbone network 1 via node devices 7a and 7d, respectively. The user terminal device 8 is connected to the access network 4a. The content sending device 6 is connected to the access network 4b.

  In the system configured as described above, when the user terminal device 8 applies for participation in the multicast group address Ga, the node device 7a receives the message, the node device 7a sends a multicast tree setting request, and the node device 7d sets the multicast tree setting. The request is received, and the network information “topology information and TE (Traffic Engineering) reservation information” of the backbone network 1 is referred to. Set Switched Path).

  Further, when the user terminal device 8 applies for participation in the multicast group address Gb, similarly, the node device 7d receives the multicast tree setting request and refers to the network information of the backbone network 1, but at this time, the shortest path is used. Since there is no empty bandwidth, this indicates that the LSP of the distribution tree having the node devices 7d, 7e, 7b and 7a that are not the shortest route as a root is set.

  Even when the multicast group addresses Ga and Gb are hierarchical contents, both contents are distributed to the same route with the node devices 7d, 7c, 7b and 7a or the node devices 7d, 7e, 7b and 7a as the root. This indicates that processing for setting the LSP of the tree is not possible.

  FIG. 13B shows an example of a PATH message that is a message for transmitting a route set in response to a request for participation in the multicast group address Ga to the downstream node devices 7c, 7b, and 7a. . FIG. 13B shows an example of a PATH message that is a message for transmitting the route set in response to the request to join the multicast group address Gb to the downstream node devices 7e, 7b, and 7a. ing. The tunnel ID (Identification) in the PATH message identifies the combination of the node device 7d connected to the content transmission device 6 and the node device 7a connected to the user terminal device 8, and is an LSP- The ID distinguishes LSPs in the same tunnel-ID (for example, at the time of Make before break). The LSP of the distribution tree set by these two IDs can be identified and managed. The bandwidth is data that the system has in advance and indicates the reserved bandwidth of the LSP.

On the other hand, there is a method for managing the bandwidth regardless of these protocols. For example, all node devices in the communication network broadcast multicast tree information and resource information held by each node device so that all node devices in the communication network can share the multicast tree information and resource information. When there is a content reception request from the user terminal device in the shared state of these information, the route by which the node device that received the reception request can reach the connection point for each multicast group address, and This makes it possible to autonomously determine whether the bandwidth required for the content can be secured (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 2003-234776 “Multicast Communication and Method, and Node Communication Method, Program, Apparatus, and Recording Medium for the Same” "Extensions to RSVP-TE for Point to Multipoint TE LSPs" draft-ietf-mpls-rsvp-te-p2mp-03.txt

  However, in the above-described conventional multicast method and system for reserving bandwidth, when a user makes an application for participation in a multicast group address, bandwidth information for viewing content cannot be transmitted to the communication network. When viewing hierarchical content, there is a problem that it is not possible to set a route that makes the content of all layers the same route.

  The present invention has been made in view of the above points, and transmits bandwidth information for a user to view content to a communication network. The communication network secures a bandwidth based on the transmitted bandwidth information, and uses the same content ID. It is an object of the present invention to provide a traffic engineering multicast distribution method, system, node, and program capable of setting a route having the same route for (Identification).

  FIG. 1 is a diagram for explaining the principle of the present invention.

The present invention (Claim 1) includes a communication network, a plurality of node devices constituting the communication network, a content transmission device connected to any one of the node devices, and at least one user terminal device. A traffic engineering multicast delivery method in a system,
In the node device,
When a multicast group participation message including a content ID for identifying content to participate in a multicast group, bandwidth information, and a multicast group address is received from a user terminal device (step 1), a multicast tree including the content ID Sending a setting request message (step 2), a multicast tree setting request message sending step;
In the node device connected to the content transmission device,
When the multicast tree setting request message is received, a route calculation unit that calculates a route in which a plurality of LSPs (Label Switched Paths) set for distribution are the same route is calculated by referring to the storage unit and calculates a route of the distribution tree ( Step 3) creating a bandwidth reservation activation message including the calculated route and bandwidth information (Step 4) route bandwidth reservation processing step;
A bandwidth securing activation message is sent to a downstream node (step 5) and a message processing step is performed.

In the present invention (Claim 2), in the path bandwidth securing processing step (Steps 3 and 4),
If there is no content ID that is the same as the content ID included in the multicast tree setting request message in the content that has already been sent, the route calculated by referring to the network information stored in the storage means and the bandwidth information are included. Create a secure bandwidth startup message,
When there is a content ID that is the same as the content ID included in the multicast tree setting request message in the content that has already been sent, the network information stored in the storage means is referred to and the bandwidth of the content that has already been sent is When there is an empty band corresponding to the band indicated in the information, a band securing activation message including the same path as the content that has already been transmitted is created.

In the present invention (Claim 3), in the path bandwidth securing processing step (Steps 3 and 4),
If there is a content ID that is the same as the content ID included in the multicast tree setting request message in the already sent content, the route calculating means refers to the network information in the storage means, and the route of the already sent content If there is no empty band corresponding to the band indicated in the band information, a route having an empty band that can secure the band of the content that has already been transmitted and the band indicated in the band information is indicated by the network information. Refer to and calculate, create a bandwidth securing start message including the calculated route,
Create a bandwidth reservation activation cancellation message that releases the LSP of the distribution tree of the content that has already been secured,
In the message processing step (step 4),
A bandwidth reservation activation message and a bandwidth reservation activation cancellation message are transmitted.

  FIG. 2 is a principle configuration diagram of the present invention.

The present invention (Claim 4) includes a communication network, a plurality of node devices constituting the communication network, a content transmission device connected to any one of the node devices, and at least one user terminal device. A traffic engineering multicast distribution system,
The node device 2
Storage means 24 storing network information;
A route calculation unit 2341 for calculating a route in which a plurality of LSPs (Label Switched Paths) set for distribution are the same route by referring to the storage unit;
When a multicast group participation message including a content ID for identifying content to participate in a multicast group, bandwidth information, and a multicast group address is received from a user terminal device, a multicast tree setting request message including the content ID is transmitted. Multicast tree setting request message sending means 231 to perform,
When the node device is a node device connected to the content transmission device 6, when a multicast tree setting request message is received, a bandwidth reservation for creating a bandwidth reservation activation message including the route and bandwidth information calculated by the route calculation means 2341 A path bandwidth securing processing unit 234 having an activation message creating unit 2342;
Message processing means 233 for sending a bandwidth securing activation message to a downstream node.

Further, the present invention (Claim 5), in the path bandwidth securing processing means 234,
When there is no content ID that is the same as the content ID included in the multicast tree setting request message in the content that has already been sent, the route calculated by referring to the network information stored in the storage means 24 and the bandwidth information are A means for creating an included bandwidth reservation activation message;
When there is a content ID that is the same as the content ID included in the multicast tree setting request message in the already sent content, the network information stored in the storage unit 24 is referred to and the route of the already sent content is Means for creating a bandwidth securing activation message including the same route as the route of the content that has already been transmitted when there is an empty bandwidth corresponding to the bandwidth indicated in the bandwidth information.

Further, the present invention (Claim 6), in the path bandwidth securing processing means 234,
If there is a content ID that is the same as the content ID included in the multicast tree setting request message in the content that has already been sent, the route calculation unit 2341 refers to the network information in the storage unit 24 and the content that has already been sent If there is no empty bandwidth corresponding to the bandwidth indicated in the bandwidth information, a route having an empty bandwidth that can secure the bandwidth of the content that has already been transmitted and the bandwidth indicated in the bandwidth information is assigned to the network. Means for referring to the information and creating a bandwidth securing activation message including the calculated route;
A bandwidth reservation activation cancellation message for releasing the LSP (Label Switched Path) of the distribution tree of the content that has already been secured,
The message processing means 233
Means for sending a band securing activation message and a band securing activation cancellation message;

The present invention (Claim 7) includes a communication network, a plurality of node devices constituting the communication network, a content transmission device connected to any one of the node devices, and at least one user terminal device. A node device in the system,
Storage means for storing network information;
A route calculating means for calculating a route in which a plurality of LSPs (Label Switched Paths) set for distribution are the same route with reference to the storage means;
When a multicast group participation message including a content ID for identifying content to participate in a multicast group, bandwidth information, and a multicast group address is received from a user terminal device, a multicast tree setting request message including the content ID is transmitted. A multicast tree setting request message sending means to perform,
When the node device is a node device connected to the content transmission device, when a multicast tree setting request message is received, a bandwidth reservation start message that creates a bandwidth reservation start message including the route and bandwidth information calculated by the route calculation means A route bandwidth securing processing means having a creating means;
Message processing means for sending a bandwidth securing activation message to a downstream node.

Further, the present invention (Claim 8) provides a path bandwidth securing processing means,
If there is no content ID that is the same as the content ID included in the multicast tree setting request message in the content that has already been sent, the route calculated by referring to the network information stored in the storage means and the bandwidth information are included. Creating a reserved bandwidth activation message;
When there is a content ID that is the same as the content ID included in the multicast tree setting request message in the content that has already been sent, the network information stored in the storage means is referred to and the bandwidth of the content that has already been sent is Means for creating a bandwidth securing activation message including the same route as the route of the content that has already been transmitted when there is an empty bandwidth corresponding to the bandwidth indicated in the information.

Further, the present invention (Claim 9) provides a path bandwidth securing processing means,
If there is a content ID that is the same as the content ID included in the multicast tree setting request message in the already sent content, the route calculating means refers to the network information in the storage means, and the route of the already sent content If there is no empty band corresponding to the band indicated in the band information, a route having an empty band that can secure the band of the content that has already been transmitted and the band indicated in the band information is indicated by the network information. Means for creating a bandwidth securing start message including the calculated route by referring to and calculating,
Creating a bandwidth reservation activation cancellation message for releasing the LSP of the distribution tree of the content that has already been secured that has been secured,
Message processing means
Means for sending a band securing activation message and a band securing activation cancellation message;

The present invention (claim 10) provides a computer,
A traffic engineering multicast distribution program that functions as the node device according to claim 7.

  As described above, according to the present invention, the bandwidth information for the user to view the computer is transmitted to the communication network. In the communication network, the bandwidth is secured by the transmitted bandwidth information, and the content having the same content ID is By securing a route for the same route, there are the following effects or advantages.

  For the user, when viewing hierarchical content, the content quality does not deteriorate and comfortable viewing is possible.

  In addition, since the carrier does not transfer only the extension layer data that cannot be decoded alone, such as when a network failure occurs, it is possible to prevent useless distribution.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[System configuration]
FIG. 3 is a system configuration diagram in one embodiment of the present invention.

  In the figure, functional elements that are the same as or equivalent to those shown in FIG.

  The system shown in FIG. 3 includes a backbone network 1 and node devices 2a, 2b, 2c, 2d, 2e, and 2f that constitute the backbone network 1 (in the following, when it is not specified which node device is the node device 2) ), Program guide server 3, access networks 4a, 4b and 4c (hereinafter referred to as access network 4 when it is not specified which access network), and user terminal devices 5a and 5b (hereinafter referred to as access network 4). Then, when it is not specified which user's terminal device, it is referred to as a user's terminal device 5) and a content sending device 6.

  The backbone network 1 is an MPLS network, the node device 2 is a node device having an MPLS function, and the program guide server device 3 distributes content information distributed by the content transmission device 6 to the user terminal devices 5a and 5b. A server device connected to the backbone network 1. The access networks 4a, 4b and 4c are connected to the backbone network 1 via node devices 2a, 2e and 2d, respectively. The user terminal devices 5a and 5b are connected to the access networks 4a and 4b, and the content transmission device 6 is connected to the access network 4c.

  Next, functions of the component devices and connections between the component devices in the above system will be described.

  FIG. 4 is a diagram showing system connections and functions in an embodiment of the present invention.

  The figure shows content information distributed from the program guide server device 3 by the user terminal devices 5a and 5b when the content transmission device 6 is transmitting content data to the node device 2d through the access network 4c. When a “multicast group participation message” including a content ID, bandwidth information, and a multicast group address is transmitted based on (for example, content ID, bandwidth information, multicast group address, etc.), the node that has received the “multicast group participation message” The device 2a transmits a “multicast tree setting request message” including the content ID.

  When the node device 2d receives the “multicast tree setting request message” and there is no content ID that is the same as the content ID included in the “multicast tree setting request message” in the already sent content, the path described later The calculation processing unit refers to the network information (for example, topology information, TE reservation information, etc.) stored in the storage means, calculates the route, and sends a “band securing start message” including the calculated route and bandwidth information. To do. For example, the “band securing start message” sent from the node devices 2c, 2b, 2a, and 2e is sequentially received, and the bandwidth is secured.

  If the content ID that is already sent out includes the same content ID as the content ID included in the “multicast tree setting request message”, the node device 2d has already sent out as a result of referring to the network information in the storage means. If there is an empty band corresponding to the band indicated in the band information in the route of the content that has been sent, the route is the same as the route of the content that has already been sent, and if there is no empty bandwidth, the bandwidth and bandwidth of the content that has already been sent A route having an empty bandwidth that can be secured with the bandwidth indicated in the information is calculated with reference to network information by a route calculation processing unit described later, and a bandwidth securing activation message including the calculated route is transmitted. For example, the node devices 2f, 2b, 2a, and 2e sequentially receive the transmitted “bandwidth securing activation message” to secure the bandwidth, and further transmit the “bandwidth securing activation cancellation message” to secure it until then. In addition, the LSP of the distribution tree of the content that has already been sent is released.

  By the connection operation between the constituent devices described above, the bandwidth information for the user to view the content is sent to the communication network. The communication network secures the bandwidth based on the sent bandwidth information and has the same content ID. The content makes it possible to secure a route for the same route.

  In the present embodiment, as a “multicast group join message” sent from the user terminal device 5, it is assumed that a content ID and band information are added to the IGMP Join message, and as a “multicast group leave message”, The IGMP Leave message shall be applied. As the “bandwidth securing activation message”, the band of the RSVP PATH message is set based on the bandwidth information, and as the “bandwidth securing activation cancel message”, the RSVP is a message for canceling the operation associated with the “bandwidth securing activation message”. It is assumed that the PATHTEAR message is applied.

  Further, the “bandwidth securing message” sent by sending the “bandwidth securing activation message” is assumed to be an RSVP RESV message, and is sent by sending the “bandwidth securing activation cancel message”. As the “band reservation cancellation message”, an RSVP RESVTEAR message is assumed.

  The details of the “band securing activation message” and the “band activation cancellation message” will be described later. The distribution tree is assumed to be a distribution from the distribution source.

[Device configuration]
The apparatus configuration of the present invention will be described below.

  Next, the configuration of devices on the network in this system will be described.

  FIG. 5 is a diagram showing a device configuration on the network according to the embodiment of the present invention.

  In the figure, the same or equivalent components as those in FIG. 4 are denoted by the same reference numerals, and the description thereof is omitted.

  The user terminal device 5 includes a multicast group join message sending unit 51 that sends a “multicast group join message” including a content ID, bandwidth information, and a multicast group address, and a multicast group leave message that sends a “multicast group join leave message”. A PC (personal computer) having a communication function including the sending unit 52.

  The node device 2 includes a message transmission / reception unit 22 that transmits / receives messages, transmission / reception of content data packets, a packet distribution unit 21 that relays signal message packets to the message transmission / reception unit 22, and a multicast control unit 23 that controls the devices. And a network information storage unit 24 that stores network information (topology information and TE reservation information).

  The node device distribution unit 21 includes connections of the lines 11 and 12 between the content transmission device 6 and the upstream node device, and the lines 13 and 14 between the downstream node device and the user terminal device 5 and the like.

  The message transmission / reception unit 22 includes a function of performing transmission / reception of each message such as a multicast group participation message reception unit 2211 that receives a “multicast group participation message”, which will be described in detail with reference to FIG.

  The multicast control unit 23 includes a participation message handling unit 231, a leave message handling unit 232, a message processing unit 233, a route bandwidth securing processing unit 234, and a route bandwidth release processing unit 235.

  The participation message handling unit 231 of the multicast control unit 23 performs a process of sending a “multicast tree setting request message” upon reception of the “multicast group participation message”.

  The leave message handling unit 232 of the multicast control unit 23 performs a process of sending a “multicast tree release request message” upon reception of the “multicast group leave message”.

The message processing unit 233 of the multicast control unit 23
Processing for securing a bandwidth by receiving a “bandwidth securing activation message” and sending a “bandwidth securing activation message” to a downstream node device;
Processing for sending a “bandwidth securing message” to the upstream node device upon reception of the “bandwidth securing message”;
Processing to send a “bandwidth reservation cancel message” to the upstream node device upon reception of the “bandwidth reservation cancel message”;
I do.

  The route bandwidth reservation processing unit 234 of the multicast control unit 23 includes a route calculation processing unit 2341. When the “multicast tree setting request message” is received via the message transmission / reception unit 22, the route calculation processing unit 2341 uses the route of the distribution tree. And a message that conveys the calculated path and bandwidth to the downstream node device is created. At this time, if there is no content ID that is the same as the content ID included in the “multicast tree setting request message” in the content that has already been transmitted, the route and bandwidth information calculated by referring to the network information is included. Create a secure bandwidth startup message.

  In addition, when the content ID that is the same as the content ID included in the “multicast tree setting request message” is included in the content that has already been transmitted, the path bandwidth reservation processing unit 234 refers to the network information and has already been transmitted. The content path includes a function of creating a “band securing start message” indicated in the band information.

  In addition, when the content ID that is the same as the content ID included in the “multicast tree setting request message” is included in the content that has already been transmitted, the path bandwidth reservation processing unit 234 displays the network information of the network information storage unit 24. When it is found that there is no empty area for the bandwidth indicated in the bandwidth information in the route of the content already sent, the bandwidth of the content already sent and the bandwidth indicated in the bandwidth information can be secured. The route calculation processing unit 2341 calculates a route with an empty bandwidth by referring to the network information in the network information storage unit 24, creates a “bandwidth securing start message” including the calculated route, and has secured it until then. "Band reservation activation cancellation message" for releasing the LSP of the distribution tree of the content that has already been sent To create.

  Note that the path calculation processing unit 2341 can be operated as an external device of the node device 2 like a PCE (Path Computation Element).

  The path bandwidth release processing unit 235 receives a “multicast tree release request message” sent from another node device via the message transmission / reception unit 22 and creates a “band securing activation cancellation message” that releases the LSP of the distribution tree. Then, the created “bandwidth secure activation cancel message” is sent to the downstream node device via the message transmitting / receiving unit 22.

  The message transmission / reception part 22 of said node apparatus 2 is demonstrated.

  FIG. 6 shows the configuration of the message transmission / reception unit in one embodiment of the present invention.

  In the figure, the message transmitting / receiving unit 22 receives a “multicast group join message” sent from the user terminal device 5, and a multicast tree that sends a “multicast tree setting request message”. A setting request message sending unit 2212, a multicast tree setting request message receiving unit 2213 that receives a “multicast tree setting request message”, and a multicast group leaving message that receives a “multicast group leaving message” sent from the user terminal 5 A message receiving unit 2214, a multicast tree release request message sending unit 2215 that sends out a “multicast tree release request message”, and a “multicast tree release request message” Multicast tree release request message receiving unit 2216 for receiving “band”, band securing activation message sending unit 2217 for sending “band securing activation message”, and bandwidth securing activation message receiving unit 2218 for receiving “band securing activation message” , A bandwidth reservation message sending unit 2219 for sending a “bandwidth securing message”, a bandwidth securing message receiving unit 2220 for receiving a “bandwidth securing message”, and a bandwidth securing activation cancellation message sending unit for sending a “bandwidth securing cancellation message” 2221, a band securing activation cancel message receiving unit 2222 that receives a “band securing canceling message”, a band securing cancel message sending unit 2223 that sends a “band securing canceling message”, and a “band securing canceling message”. And a bandwidth reservation cancellation message receiving unit 2224.

  Next, the function of each node device 2 in FIG. 4 will be described.

The node devices 2a and 2e
The multicast group join message receiving unit 2211 receives the “multicast group join message” and the multicast tree setting request message sending unit 2212 sends the “multicast tree setting request message”;
The multicast group leave message receiving unit 2214 receives the “multicast group leave message” and sends the “multicast tree release request message” from the multicast tree release request message sending unit 2215;
The band securing activation message receiving unit 2218 receives the “band securing activation message” and the message processing unit 233 secures the band;
The band securing activation cancel message receiving unit 2222 receives the “band securing activation canceling message”, and the route band releasing processing unit 235 releases the band;
This is a node device having a function.

The node devices 2b, 2c and 2f are
The “bandwidth securing activation message” is transmitted and received by the bandwidth securing activation message receiving unit 2218 and the bandwidth securing activation message sending unit 2217, and the bandwidth is secured by the message processing unit 233;
The bandwidth securing activation cancel message receiving unit 2222 and the bandwidth securing activation canceling message transmitting unit 2221 transmit and receive “band securing activation canceling message”, and the path bandwidth releasing processing unit 235 releases the bandwidth;
This is a node device having a function.

  The node device 2d receives a “multicast setting request message” and a message for sending out the created bandwidth reservation activation cancellation message together with the route bandwidth reservation processing unit 234 and the route bandwidth release processing unit 235 having the route calculation processing unit 2341. The transmission / reception unit 22 is used.

  When the path bandwidth reservation processing unit 234 of the node device 2d receives the “multicast tree setting request message” sent from the node devices 2a and 2e via the multicast tree setting request message receiving unit 2213 of the message transmitting / receiving unit 22, the path calculation is performed. The processing unit 2341 calculates the route of the distribution tree, and creates a message that conveys the calculated route and bandwidth to the downstream node device. At this time, if there is no content ID that is the same as the content ID included in the “multicast tree setting request message” in the content that has already been transmitted, the route and bandwidth information calculated by referring to the network information is included. Processing including creating a “bandwidth securing activation message” is performed.

  Further, the path bandwidth reservation processing unit 234 of the node device 2d refers to the network information when there is a content ID that is the same as the content ID included in the “multicast tree setting request message” among the contents that have already been transmitted. The “band securing start message” indicated in the band information is created in the route of the content that has already been transmitted.

  In addition, when the content ID that is the same as the content ID included in the “multicast tree setting request message” is included in the content that has already been transmitted, the path bandwidth reservation processing unit 234 refers to the network information and has already been transmitted. If it is found that there is no empty area for the bandwidth indicated in the bandwidth information in the content path, the route with the empty bandwidth that can secure the bandwidth of the content already sent and the bandwidth indicated in the bandwidth information is selected. Then, the route calculation processing unit 2341 calculates with reference to the network information, creates a “bandwidth securing start message” including the calculated route, and releases the LSP of the distribution tree of the already sent content that has been secured so far Create a “bandwidth secure activation cancellation message”.

  The path bandwidth release processing unit 235 of the node device 2d receives the “multicast tree release request message” sent from the node devices 2a and 2e via the multicast tree release request message reception unit 2216 of the message transmission / reception unit 22, and receives the distribution tree. The processing including the creation of the “band securing activation cancellation message” for releasing the LSP is performed, and the created “band securing activation message” is transmitted via the band securing activation message sending unit 2217 of the message transmitting / receiving unit 22.

[Band reservation processing]
Next, the band securing process of the node device 2 in the system shown in FIG. 4 will be described.

  FIG. 7 is a diagram for explaining the outline of the bandwidth securing process according to the embodiment of the present invention.

  Hereinafter, a case of hierarchical content will be described as an example. The lower part of FIG. 7 shows a configuration example of hierarchical content transmitted by the content transmission device 6. Content data 1 corresponding to the base layer has a content ID of C1, a band of BWg1, and a multicast group address of G1, and content data “2” of the next layer has a content ID of C1, a band of BWg2, and a multicast group Content data “3”, which is address G2, and is the highest layer, has a content ID of C1, a bandwidth of GWg3, and a multicast group address of G3. It is assumed that all content data “1” to “3” are sent from the content sending device 6 to the node device 2d. Information such as C1, BWg1 to BWg3, and G1 to G3 is distributed by the program guide server device 3 to the terminal device 5 of the user.

  In order to join the multicast group addresses G1 and G2, the user terminal device 5a adds two “multicast group join messages” (in FIG. 7, the multicast group join message adds content ID and bandwidth information to the IGMP Join message. (IGMP) Join (G1, BWg1, C1) and Join (G2, BWg2, C1) (the same applies below) are sent out.

  Upon receiving the “multicast group join message” sent from the user terminal 5a, the node device 2a identifies the node device 2d connected to the content sending device 6 using a bootstrap message in PIM-SM (Sparse-Mode). Then, a “multicast tree setting request message” (not shown; the same applies hereinafter) is sent to the node device 2d.

  The node device 2d receives the “multicast tree setting request message” sent from the node device 2a, and receives the “bandwidth securing start message” (in FIG. 7, the bandwidth securing activation message is based on the bandwidth of the RSVP PATH message based on the bandwidth information. Create a message using the PATH message (same below). Examples of the “band securing activation message” are shown in the upper sections (1) and (2) of FIG.

  The bandwidth reservation activation message (1) in FIG. 7 corresponds to (IGMP) Join (G1, BWg1, C1), the path becomes the node devices 2d, 2c, 2b, and 2a, and the bandwidth information becomes BWg1. It becomes the composition including becoming.

  The bandwidth reservation activation message (2) in FIG. 7 corresponds to (IGMP) Join (G2, BWg2, C1), and the content ID is the same as the multicast group participation message described above. The route includes the same route as (1), and the bandwidth information becomes BWg2. As a result, even when multicast participation messages including the same content ID are sent at the same time or after a certain time, it is possible to set a route to be the same route.

  Upon receiving the bandwidth securing message (1), the node device 2c secures the bandwidth of BWg1 on the line between the upstream node devices 2d, knows that the downstream node device is the node device 2b, and sends the node device 2b to the node device 2b. A bandwidth securing message (3) in which the portion related to the node 2c is deleted from the bandwidth securing activation message (1) is constructed and transmitted. When the bandwidth securing activation message (2) is received, the bandwidth of BWg2 is secured on the line between the upstream node devices 2d, knows that the downstream node device is the node device 2b, and activates bandwidth securing to the node device 2b. A bandwidth securing activation message (4) in which the part related to the node device 2c is deleted from the message (2) is constructed and transmitted.

  Similarly, when the node device 2b receives the bandwidth securing activation message (3), the node device 2b secures the bandwidth of BWg1 on the line between the node devices 2c and sends the bandwidth securing activation message (5) to the node device 2a. When the bandwidth securing activation message (4) is received, the bandwidth of BWg2 is secured on the line between the node devices 2c, and the bandwidth securing activation message (6) is transmitted to the node device 2a.

  Similarly, when the node 2a receives the bandwidth securing activation message (5), the bandwidth of the BWg1 is secured on the line between the node devices 2b, and when the bandwidth securing activation message (6) is received, the node device 2a establishes the line between the node devices 2b. The bandwidth of BWg2 is secured. Further, the node device 2a that has received the bandwidth securing activation message (5) and the bandwidth securing activation message (6) responds to each bandwidth securing activation message with a bandwidth securing message (in FIG. 7, the bandwidth securing message is an RSVP RESV message). Therefore, it is described as RESV (the same applies hereinafter) to the node device 2b, and the transmitted bandwidth reservation message is sent to the node device 2d following the reverse flow of the bandwidth reservation activation message.

  The message sequence for the band securing process is shown below.

  FIG. 8 is a sequence chart of the bandwidth securing process according to the embodiment of the present invention.

  Step A1) The content sending device 6 sends the content data 1 to 3 to the node device 2d.

  Step A2) The user terminal device 5a sends a multicast group join message (IGMP) Join (G1, BWg1, C1) to join the multicast group addresses G1 and G2.

  Step A3) Upon receiving the “multicast group join message” via the message transmission / reception unit 22, the node device 2a sends out a “multicast tree setting request message” from the participation message corresponding unit 231. Note that the transmission of (IGMP) Join (G2, BWg2, C1) is the same process, so the description is omitted (the same applies hereinafter).

  Step A4) The path bandwidth securing processing unit 234 of the node device 2d creates a bandwidth securing activation message (1) corresponding to the multicast group address G1 and a bandwidth securing activation message (2) corresponding to the multicast group address G2. The network information in the network information storage unit 24 is referred to.

  Step A5) The path bandwidth reservation processing unit 234 of the node device 2d creates a bandwidth reservation start message (1) and a bandwidth reservation start message (2) corresponding to the multicast group address G2.

  Step A6) The message processing unit 233 of the node device 2d sends a bandwidth securing activation message (1) to the node device 2c via the message transmission / reception unit 22.

  Step A7) When the node device 2c receives the bandwidth securing activation message (1) via the message transmission / reception unit 22, the path bandwidth securing processing unit 234 secures the bandwidth of BWg1 on the line between the node devices 2d.

  Step A8) The message processing unit 233 of the node device 2c sends a bandwidth securing activation message (3) to the node device 2b, and when the node device 2b receives the bandwidth activation securing message (3), the path bandwidth securing processing unit 234 The bandwidth of BWg1 is secured on the line between the node devices 2c.

  Step A9) When the message processing unit 233 of the node device 2b sends the bandwidth securing activation message (5) to the node device 2a and the node device 2a similarly receives the bandwidth securing activation message (5), the route bandwidth securing processing unit In 234, the bandwidth of BWg1 is secured on the line between the node devices 2b.

  Step A10) In addition, the message processing unit 233 of the node device 2d sends a bandwidth securing activation message (2) to the node device 2c.

  Step A11) Upon receiving the bandwidth securing activation message (2) from the node device 2d, the node device 2c secures the bandwidth of BWg2 on the line between the node devices 2d in the path bandwidth securing processing unit 234.

  Step A12) When the message processing unit 233 of the node device 2c sends the bandwidth securing activation message (4) to the node device 2b and the node device 2b similarly receives the bandwidth securing activation message (4), the route bandwidth securing processing unit At 234, the bandwidth of BWg2 of the line between the node devices 2c is secured.

  Step A13) The message processing unit 233 of the node device 2b sends a bandwidth securing activation message (6) to the node device 2a, and when the node device 2a receives the bandwidth securing activation message (6) in the same manner, The bandwidth securing processor 234 secures the bandwidth of BWg2 on the line between the node devices 2b.

  Step A14) Further, the message processing unit 233 of the node device 2a sends a bandwidth securing message corresponding to the bandwidth securing activation message (5) to the node device 2b.

  Step A15) The message processing unit 233 of the node device 2a further transmits a bandwidth securing message corresponding to the bandwidth securing activation message (6).

  Step A16) The transmitted bandwidth reservation message follows the reverse flow of the bandwidth reservation activation message (reverse path) and is transmitted to the node device 2d. When the message processing unit 233 of the node device 2d receives the bandwidth securing message, the message processing unit 233 assigns a label to the content data 1 according to FEC (Forwarding Equivalence Class) and transfers the content data 1 to the node device 2a.

  Step A17) The node device 2a sends the content data 1 with the label removed to the user terminal device 5a.

  Step A18) Further, the node device 2d assigns a label to the content data 2 in accordance with FEC, and transfers it to the node device 2a.

  Step A19) The node device 2a sends the content data 2 to the user terminal device 5a.

[Operation when there is participation later]
FIG. 9 is a diagram for explaining the outline when there is a subsequent participation in the embodiment of the present invention, and when the user terminal device 5a has already participated in the multicast group addresses G1 and G2. In addition, when the user terminal device 5b joins the multicast group addresses G1, G2, and G3 later, the content route that has already been sent does not have an empty bandwidth for the bandwidth to be joined later, and has already been sent. An outline of processing for securing a route with an empty bandwidth that can secure a bandwidth of content and a bandwidth to be joined later and releasing an LSP of a distribution tree of content that has been secured and used so far and has been transmitted is shown. .

  In order to join the multicast group addresses G1, G2, and G3, the user terminal device 5b has three multicast group join messages (IGMP) Join (G1, BWg1, C1), Join (G2, BWg2, C1), Join. (G3, BWg3, C1) is sent to the node device 2e.

  The node device 2d receives the multicast tree setting request message sent from the node device 2e that has received the multicast group join message, and tries to set the route so that the content including the same content ID becomes the same route. Tries to add G3 to the route set when the user's terminal device 5a participates, but since there is no room to add G3 to this route, stop using the route that has already been set and reroute the route. This is a case where a process for securing is performed.

  The new paths are the node devices 2d, 2f, 2b and 2a, and branch from 2b to become 2b and 2e. Examples of the band securing activation message are shown in FIGS. 9 (1), (2) and (3). 9 corresponds to (IMGP) Join (G1, BWg1, C1) sent from the terminal devices 5a and 5b of the user, and the route is the node device 2d, 2f, 2b and 2a are branched from 2b and become 2b and 2e, and the band information becomes BWg1.

  8 corresponds to the (IGMP) Join (G2, BWg2, C1) sent from the user terminal devices 5a and 5b, and the bandwidth reservation activation message (1) and It is configured to include a route that is the same route and that the bandwidth information is BWg2. The bandwidth securing activation message (3) in FIG. 9 corresponds to (IGMP) Join (G3, BWg3, C1) sent from the user terminal device 5b, and is the same as the bandwidth securing activation message (1). It is configured to include a route that becomes a route and that the bandwidth information is BWg3.

  When the node device 2f receives the bandwidth securing activation message (1), the node device 2f secures the bandwidth of BWg1 on the line between the node devices 2d and sends the bandwidth securing activation message (4) to the node device 2b. When the bandwidth securing activation message (2) is received, the bandwidth of Bwg2 is secured on the line between the node devices 2d, the bandwidth securing activation message (5) is transmitted to the node device 2b, and further the bandwidth securing activation message (3). Is received, the BWg3 bandwidth is secured on the line between the node devices 2d, and a bandwidth securing activation message (6) is sent to the node device 2b.

  Similarly, when the node device 2b receives the bandwidth securing activation message (4), it secures the bandwidth of BWg1 on the line between the node devices 2f, sends the bandwidth securing activation message (7) to the node device 2a, and sends it to the node device 2e. Also sends a bandwidth securing activation message (9). When the bandwidth securing activation message (5) is received, the bandwidth of BWg2 is secured on the line between the node devices 2f, the bandwidth securing activation message (8) is transmitted to the node device 2a, and the bandwidth securing activation is also performed on the node device 2e. Send message (10). Further, when the bandwidth securing activation message (6) is received, the bandwidth of BWg3 is secured on the line between the node devices 2f, and the bandwidth securing activation message (11) is transmitted to the node device 2e.

  Similarly, when the node device 2a receives the bandwidth securing activation message (7), it secures the bandwidth of BWg1 on the line between the node devices 2b. When the bandwidth securing activation message (8) is received, the bandwidth of BWg2 is secured on the line between the node devices 2b.

  Similarly, when the node device 2e receives the bandwidth securing activation message (9), the bandwidth of the BWg1 is secured on the line between the node devices 2b. Further, when the bandwidth securing activation message (10) is received, the bandwidth of BWg2 is secured on the line between the node devices 2b. Further, when the bandwidth securing activation message (11) is received, the bandwidth of BWg3 is secured on the line between the node devices 2b.

  Further, the node device 2a that has received the bandwidth securing activation messages (7) and (8) and the node device 2e that has received the bandwidth securing activation messages (9), (10), and (11) have each bandwidth securing activation in the node device 2b. A bandwidth securing message is sent in response to the message, and the transmitted bandwidth securing message is sent to the node device 2d following the reverse flow of the bandwidth securing activation message.

  On the other hand, since the bandwidth of the path of the node devices 2d, 2c, 2b, and 2a that has been secured up to that point is no longer used, the bandwidth securing activation cancellation message (in FIG. Since the activation cancellation message is an RSVP PATHTEAR message, it is described using the PATHTEAR message (the same applies hereinafter). Examples of the band securing activation cancellation message are shown in FIGS. 9 (21) and 9 (22).

  The bandwidth securing activation cancellation message (21) in FIG. 9 is configured to include that the route to be released becomes the node devices 2d, 2c, 2b and 2a. The bandwidth securing activation cancellation message (22) in FIG. 9 is configured to include that the route to be released becomes the node devices 2d, 2c, 2b, and 2a.

  When the node device 2c receives the bandwidth reservation activation cancellation message (21), the node device 2c stores the bandwidth information corresponding to the tunnel ID and the LSP-ID, and then knows that the bandwidth is BWg1. (Same below), release the bandwidth of BWg1 reserved on the line between the upstream node devices 2d, know that the downstream node device is the node device 2b, and notify the node device 2b of the bandwidth reservation activation cancellation message. A bandwidth reservation activation cancellation message (23) in which the part related to the node device 2c is deleted from (21) is constructed and transmitted. Also, when the bandwidth securing activation cancellation message (22) is received, the bandwidth of BWg2 secured on the line between the upstream node devices 2d is released, knowing that the downstream node device is the node device 2b, and the node device 2b. Then, a bandwidth securing activation cancellation message (24) in which the portion related to the node device 2c is deleted from the bandwidth securing activation cancellation message (22) is constructed and transmitted.

  Similarly, when the node device 2b receives the bandwidth securing activation cancel message (23), it releases the bandwidth of BWg1 secured on the line between the node devices 2c, and sends a bandwidth securing activation cancel message (25) to the node device 2a. Send it out. When the bandwidth reservation activation cancel message (24) is received, the bandwidth of BWg2 reserved in the line between the node devices 2c is released, and the bandwidth reservation activation cancellation message (26) is transmitted to the node device 2a.

  Similarly, when the node device 2a receives the bandwidth reservation activation cancellation message (25), the node device 2a releases the bandwidth of the BWg1 reserved in the line between the node devices 2b. In addition, when the bandwidth securing activation cancellation message (26) is received, the bandwidth of Bwg2 secured on the line between the node devices 2b is released. Further, the node device 2a that has received the bandwidth reservation activation cancellation messages (25) and (26) responds to each bandwidth reservation activation cancellation message (in FIG. 9, the bandwidth reservation cancellation message is an RSVP RESVTEAR message). Therefore, the bandwidth reservation cancellation message is sent to the node device 2d following the reverse flow of the bandwidth reservation activation cancellation message.

  In the above case, the multicast group addresses G1, G2, and G3 are joined later. However, in the case of joining the multicast group address G1, the node device 2d has a route from the node device 2b. By sending a bandwidth securing activation message including branching, the node device 2e receives the bandwidth securing activation message and can secure the bandwidth of BWg1 on the line between the node devices 2b.

  Next, a message sequence when there is participation afterward in FIG. 9 will be described.

  FIG. 10 is a sequence chart of processing when there is participation later in the embodiment of the present invention.

  The figure shows a sequence among the user terminal devices 5 a and 5 b, the node devices 2 a to 2 f, and the content transmission device 6.

  In the following description, it is assumed that the user terminal device 5a has already joined the multicast group addresses G1 and G2.

  Step B1) In order for the user terminal device 5b to participate in the multicast group addresses G1, G2, and G3, a multicast group join message (IGMP) Join (G1, BWg1, C1) is sent to the node device 2e.

  Step B2) The join message handling unit 231 of the node device 2e receives the multicast group join message and sends a multicast tree setting request message to the node device 2d. Note that the transmission of (IGMP) Join (G2, BWg2, C1) Join (G3, BWg3, C1) is the same process, so the description is omitted.

  Step B3) When receiving the multicast tree setting request message, the path bandwidth reservation processing unit 234 of the node device 2d refers to the network information in the network information storage unit 24.

  Step B4) The bandwidth corresponding to (IGMP) Join (G1, BWg1, C1) is set in the node device 2d so that the route bandwidth securing processing unit 234 sets a route again by the route calculation processing unit 2341 and secures the bandwidth. Bandwidth secure start message (2) corresponding to secure start message (1), (IGMP) Join (G2, BWg2, C1), Band secure start message (3) corresponding to (IGMP) Join (G3, BWg3, C1) Create

  Step B5) The message processing unit 233 of the node device 2d sends a bandwidth securing activation message (1) to the node device 2f.

  Step B6) When the node device 2f receives the bandwidth securing activation message (1), the route bandwidth securing processing unit 234 secures the bandwidth of BWg1 in the line between the node devices 2d.

  Step B7) The message processing unit 233 of the node device 2f sends a bandwidth securing activation message (4) to the node device 2b. Similarly, when the node device 2b receives the bandwidth securing activation message (4), the route bandwidth securing processing unit 234 secures the bandwidth of BWg1 on the line between the nodes 2f.

  Step B8) When the message processing unit 233 of the node device 2b sends the bandwidth securing activation message (7) to the node device 2a and the node device 2a receives the bandwidth securing activation message (7) in the same manner, the path bandwidth securing processing unit In 234, the bandwidth of BWg1 is secured on the line between the node devices 2b.

  Step B9) In the message processing unit 233 of the node device 2b, the bandwidth securing activation message (9) is similarly sent to the node device 2e.

  Step B10) Similarly, when the node device 2e receives the bandwidth securing activation message (9), the route bandwidth securing processing unit 234 secures the bandwidth of BWg1 on the line between the node devices 2b.

  Step B11) Further, the message processing unit 233 of the node device 2d sends a bandwidth securing activation message (2) to the node device 2f.

  Step B12) When the node device 2f receives the bandwidth securing activation message (2), the route bandwidth securing processing unit 234 secures the bandwidth of BWg2 in the line between the nodes 2d.

  Step B13) When the message processing unit 233 of the node device 2f sends the bandwidth securing activation message (5) to the node device 2b and the node device 2b similarly receives the bandwidth securing activation message (5), the route bandwidth securing processing unit 24, a bandwidth of BWg2 is secured on the line between the node devices 2f.

  Step B14) The message processing unit 233 of the node device 2b sends a bandwidth securing activation message (8) to the node device 2a. When the node device 2a receives the bandwidth securing activation message (8), the route bandwidth securing processing unit 234 secures the bandwidth of BWg2 on the line between the node devices 2b.

  Step B15) Similarly, the message processing unit 233 of the node device 2b sends a bandwidth securing activation message (10) to the node device 2e.

  Step B16) Upon receiving the bandwidth securing activation message (10), the node device 2e secures the bandwidth of BWg2 in the line between the node devices 2b in the path bandwidth securing processing unit 234.

  Step B17) Further, the message processing unit 233 of the node device 2d sends a bandwidth securing activation message (3) to the node device 2f.

  Step B18) When the node device 2f receives the bandwidth securing activation message (3), the route bandwidth securing processing unit 234 secures the bandwidth of the bandwidth of BWg3 in the line between the node devices 2d.

  Step B19) The message processing unit 233 of the node device 2f sends a bandwidth securing activation message (6) to the node device 2b. Similarly, when the node device 2b receives the bandwidth securing activation message (6), the route bandwidth securing processing unit 234 secures the bandwidth of the BWg3 between the node devices 2f.

  Step B20) The message processing unit 233 of the node device 2b sends a bandwidth securing activation message (11) to the node device 2e. Similarly, when the node device 2e receives the bandwidth securing activation message (11), the route bandwidth securing processing unit 234 secures the bandwidth of the line BWg3 between the node devices 2b.

  Step B21) The message processing unit 233 of the node device 2a that has received the bandwidth activation securing messages (7) and (8) sends a bandwidth securing message to the node device 2b in response to each bandwidth securing activation message.

  Step B22) The message processing unit 233 of the node device 2e that has received the bandwidth securing activation messages (9), (10), and (11) also sends a bandwidth securing message to the node device 2b in response to each bandwidth securing activation message.

  Step B23) The message processing unit 233 of the node device 2b transfers the transmitted bandwidth reservation message to the node device 2b by following the reverse flow of the bandwidth reservation activation message.

  Step B24) The node device 2b sends the content data 1 to the node device 2a.

  Step B25) The node device 2d removes the label from the user terminal 5a and transmits the content data 1.

  Step B26) The node device 2b also sends the content data 1 to the node device 2e.

  Step B27) The node device 2e removes the label from the user terminal device 5b and sends out the content data 1.

  Step B28) Further, the node device 2d assigns a label to the content data 2 in accordance with FEC and transfers it to the node device 2a.

  Step B29) The node device 2b sends the content data 2 to the node device 2a.

  Step B30) The node device 2a removes the label from the user's terminal device 5a and sends out the content data 2.

  Step B31) The node device 2b also sends the content data 2 to the node device 2e.

  Step B32) The node device 2e removes the label from the user terminal device 5b and sends the content data 2.

  Step B33) Further, the node device 2d assigns a label to the content data 3 in accordance with FEC and transfers the content data 3 to the node device 2e.

  Step B34) The node device 2e removes the label from the user terminal device 5b and sends the content data 3.

  Step B35) On the other hand, the path bandwidth release processing unit 235 of the node device 2d creates bandwidth reservation activation cancellation messages (21) and (22) in order to release the LSP of the distribution tree that is no longer used.

  Step B36) The path bandwidth release processing unit 235 of the node device 2d sends a bandwidth reservation activation cancellation message (21) to the node device 2c.

  Step B37) The path bandwidth release processing unit 235 of the node device 2c releases the bandwidth of the BWG 1 that has been secured on the line between the node devices 2d.

  Step B38) The path bandwidth release processing unit 235 of the node device 2c sends a bandwidth reservation cancellation message (23) to the node device 2b. Similarly, when receiving the bandwidth securing activation cancellation message (23), the path bandwidth releasing processing unit 235 of the node device 2b releases the bandwidth of BWg1 secured on the line between the node devices 2c.

  Step B39) The node device 2b sends a bandwidth securing activation cancellation message (25) to the node device 2a, and the node device 2c similarly receives the bandwidth securing activation cancellation message (25) in the path bandwidth release processing unit 235. The bandwidth of BWg1 secured on the line between the node devices 2b is released.

  Step B40) The path bandwidth release processing unit 235 of the node device 2d sends a bandwidth reservation activation cancellation message (22) to the node device 2c.

  Step B41) Upon receiving the band securing activation cancellation message (22), the node device 2c releases the bandwidth of Bwg2 secured in the line between the node devices 2d in the path bandwidth releasing processing unit 235.

  Step B42) A route securing activation cancellation message (24) is sent to the path bandwidth release processing unit 235 of the node device 2c and the node device 2b. Similarly, when the node device 2b receives the bandwidth reservation activation cancellation message (24), the route bandwidth release processing unit 235 releases the bandwidth of the BWg2 that has been secured on the line between the node devices 2c.

  Step B43) The path bandwidth release processing unit 235 of the node device 2b sends a bandwidth securing activation cancellation message (26) to the node device 2a. Similarly, when the node device 2a receives the bandwidth reservation activation cancellation message (26), the route bandwidth release processing unit 235 releases the bandwidth of the BWg2 that has been secured on the line between the node devices 2b.

  Step B44) Further, the node device 2a that has received the bandwidth reservation activation cancellation messages (25) and (26) sends a bandwidth reservation cancellation message to the node device 2b in response to each bandwidth reservation activation cancellation message. The transmitted bandwidth reservation cancellation message is sent to the node device 2d following the reverse flow of the bandwidth reservation activation cancellation message.

[Remove from multicast group address]
FIG. 11 is a diagram for explaining the outline when there is a detachment in one embodiment of the present invention, where the user terminal device 5a has already joined the multicast group addresses G1 and G2 and the user terminal device When the user terminal device 5b leaves the multicast group addresses G1, G2, and G3 when the user 5b is already participating in the multicast group addresses G1, G2, and G3, the distribution tree LSP is opened, and the user terminal An outline of processing for securing a bandwidth (BWg1 and BWg2 bandwidth) by the device 5a continuing to participate in the multicast group addresses G1 and G2 is shown.

  In order for the user terminal device 5b to leave the multicast group addresses G1, G2, and G3, three multicast group leave messages (in FIG. 11, the multicast group leave message is an IGMP leave message (IGMP) Leave). (G1), Leave (G2), and Leave (G3) (same below) are transmitted.

  When the node device 2 receives a multicast tree release request message (not shown; the same applies hereinafter) sent from the node device 2a that has received the multicast group leave message, the node device 2b receives G1 (BWg1) and G2 (BWg2). A bandwidth securing activation message that does not branch is created, and for G3 (BWg3) that is no longer used, a bandwidth securing activation cancellation message that releases the LSP of the distribution tree is created. Examples of the band securing activation message are shown in FIGS. 11 (1) and 11 (2).

  Upon receipt of the bandwidth securing activation message (1) in FIG. 11, the node device 2f continues the bandwidth of BWg1 secured on the line of the node device 2d, and sends the bandwidth securing activation message (3) to the node device 2b. . When the bandwidth securing activation message (2) is received, the bandwidth of BWg2 secured on the line between the node devices 2d is continued, and the bandwidth securing activation message (4) is transmitted to the node device 2b.

  Similarly, when the node device 2b receives the bandwidth securing activation message (3), it continues the bandwidth of BWg1 secured on the line between the node devices 2f, and sends the bandwidth securing activation message (5) to the node device 2a. When the bandwidth securing activation message (4) is received, the bandwidth of BWg2 secured on the line between the node devices 2f is continued, and the bandwidth securing activation message (6) is transmitted to the node device 2a.

  Similarly, when the node device 2a receives the bandwidth securing activation message (5), the bandwidth of BWg1 secured on the line between the node devices 2b is continued. In addition, when the bandwidth securing activation message (6) is received, the bandwidth of BWg2 secured on the line between the node devices 2b is continued. Further, the node device 2a that has received the bandwidth securing activation messages (5) and (6) sends a bandwidth securing message to the node device 2b in response to each bandwidth securing activation message, and the transmitted bandwidth securing message is the bandwidth securing activation message. The message flow is traced in reverse and sent to the node device 2d.

  Since the node device 2b no longer branches to the node device 2e in the route setting of the bandwidth reservation activation messages (3) and (4), the node device 2e sends a bandwidth reservation activation cancellation message (21) and ( 22).

  When the node device 2e receives the bandwidth securing activation cancellation message (21), the node device 2e releases the bandwidth of BWg1 secured on the line between the node devices 2b. In addition, when the bandwidth securing activation cancellation message (22) is received, the bandwidth of BWg2 secured on the line between the node devices 2b is released. Furthermore, the node device 2e that has received the bandwidth reservation activation cancellation messages (21) and (22) sends a bandwidth reservation cancellation message to the node device 2b in response to each bandwidth reservation activation cancellation message.

  On the other hand, since the LSP of the distribution tree of G3 (BWg3) is not used, the node device 2d sends a bandwidth reservation activation cancellation message (23) to the node device 2f in order to release the reserved LSP of the distribution tree. Upon receiving the bandwidth securing activation cancel message (22), the node device 2f releases the bandwidth of BWg3 secured on the line between the node devices 2d and sends the bandwidth securing activation cancel message (24) to the node device 2b.

  Similarly, when the node device 2b receives the bandwidth securing activation cancel message (24), it releases the bandwidth of BWg3 secured on the line between the node devices 2f, and sends a bandwidth securing activation cancel message (25) to the node device 2e. Send it out.

  Similarly, when the node device 2e receives the bandwidth reservation activation cancellation message (25), the node device 2e releases the bandwidth of the BWg3 reserved for the line between the node devices 25. Furthermore, the node device 2e that has received the bandwidth reservation activation cancellation message (25) sends a bandwidth reservation cancellation message to the node device 2b. The bandwidth securing cancellation message is sent to the node device 2d following the reverse flow of the bandwidth securing activation cancellation message.

  Next, a message sequence when there is a withdrawal is shown.

  FIG. 12 is a sequence chart of processing in the case of separation in one embodiment of the present invention. This figure is a sequence chart among the user terminal devices 5a and 5b, the node devices 2a, 2b, 2d to 2f, and the content transmission device 6.

  Step C1) When the user terminal device 5a participates in the multicast group addresses G1 and G2 and the user terminal device 5b also participates in the multicast group addresses G1, G2 and G3, the user terminal device 5b is multicast. In order to leave the group addresses G1, G2 and G3, a multicast group leave message (IGMP) Leave (G1) is transmitted.

  Step C2) The node device 2a that has received the multicast group leaving message sends a multicast tree release request message to the node device 2d in the leaving message corresponding unit 232. Since (IGMP) Leave (G2) and Leave (G3) are transmitted in the same step, description thereof is omitted.

  Step C3) The node device 2d receives the multicast tree release request message, and refers to the network information in the network information storage unit 24 in the path bandwidth reservation processing unit 234.

  Step C4) The path bandwidth securing processing unit 234 of the node device 2d creates bandwidth securing activation messages (1) and (2) that do not branch to the node device 2e.

  Step C5) The message processing unit 233 of the node device 2d sends a bandwidth securing activation message (1) to the node device 2f.

  Step C6) Upon receiving the bandwidth securing activation message (1), the node device 2f continues the bandwidth of BWg1 secured on the line between the node devices 2d.

  Step C7) The node device 2f sends a bandwidth securing activation message (3) to the node device 2b. Similarly, the node device 2b receives the bandwidth securing activation message (3) and continues the bandwidth of BWg1 secured on the line between the node devices 2f.

  Step C8) The node device 2b sends a bandwidth securing activation message (5) to the node device 2a, and the node device 2a similarly receives the bandwidth securing activation message (5) and secures it on the line between the node devices 2b. The BWg1 band is continued.

  Step C9) Further, the node device 2d sends a bandwidth securing activation message (2) to the node device 2f.

  Step C10) Upon receiving the bandwidth securing activation message (2), the node device 2f continues the bandwidth of BWg2 secured on the line between the node devices 2d.

  Step C11) The node device 2f sends a bandwidth securing activation message (4) to the node device 2b, and the node device 2b similarly receives the bandwidth securing activation message (4) and secures it on the line between the node devices 2f. The bandwidth of BWg2 is continued.

  Step C12) The node device 2b sends a bandwidth securing activation message (6) to the node device 2a, and the node device 2a receives the bandwidth securing activation message in the same manner, and the BWg2 secured on the line between the node devices 2b. Continue bandwidth.

  Step C13) Further, the node device 2a that has received the bandwidth reservation activation messages (5) and (6) transmits a bandwidth reservation message corresponding to each bandwidth reservation activation message. The transmitted bandwidth reservation message follows the reverse flow of the bandwidth reservation activation message and is sent to the node device 2d.

  Step C14) Since the node device 2b no longer branches to the node device 2e in the route setting of the bandwidth reservation activation messages (3) and (4), the route bandwidth release processing unit 235 stops using it. In order to release the bandwidth of the branch, bandwidth reservation activation cancellation messages (21) and (22) are created.

  Step C15) The message processing unit 233 of the node device 2b sends the created bandwidth reservation activation cancel message (21) to the node device 2e.

  Step C16) Upon receiving the band securing activation cancellation message (21), the node device 2e releases the bandwidth of BWg1 that has been secured in the line between the node devices 2b in the path bandwidth releasing processing unit 235.

  Step C17) Further, the message processing unit 233 of the node device 2b sends a bandwidth securing activation cancellation message (22) to the node device 2e.

  Step C18) Upon receiving the bandwidth securing activation cancellation message (22), the path bandwidth releasing processing unit 235 of the node device 2e releases the bandwidth of BWg2 that has been secured on the line between the node devices 2b.

  Step C19) Further, the message processing unit 233 of the node device 2e that has received the bandwidth reservation activation cancellation messages (21) and (22) sends a bandwidth reservation cancellation message to the node device 2b in response to each bandwidth reservation activation cancellation message.

  Step C20) The node device 2d assigns a label to the content data 1 in accordance with FEC and transfers it to the node device 2a.

  Step C21) The node device 2a removes the label from the user terminal 5a and sends out the content data 1.

  Step C22) The node device 2d assigns a label difficult to FEC to the content data 2 and transfers it to the node device 2a.

  Step C23) The node device 2a removes the label from the user terminal device 5a and sends out the content data 2.

  Step C24) On the other hand, the path bandwidth release processing unit 235 of the node device 2d creates a bandwidth reservation activation cancellation message (23) in order to release the LSP of the BWg3 distribution tree that is no longer used.

  Step C25) The message processing unit 233 of the node device 2d sends a bandwidth reservation activation cancellation message to the node device 2f.

  Step C26) Upon receiving the bandwidth securing activation cancellation message (23), the node device 2f releases the bandwidth of BWg3 that has been secured on the line between the node devices 2d in the path bandwidth release processing unit 235.

  Step C27) The node device 2f uses the message processing unit 233 to send a bandwidth reservation activation cancel message (24) to the node device 2b. Similarly, the node device 2b receives the bandwidth securing activation cancellation message (24), and releases the bandwidth of BWg3 secured in the line between the node devices 2f in the path bandwidth releasing processing unit 235.

  Step C28) The message processing unit 233 of the node device 2b sends a bandwidth reservation cancellation message (25) to the node device 2e. Similarly, the node device 2e receives the bandwidth reservation cancellation message (25), and performs route bandwidth release processing. The unit 235 releases the bandwidth of BWg3 reserved for the line between the node devices 2b.

  Step C29) Further, the node device 2e that has received the bandwidth reservation activation cancellation message (25) sends out the bandwidth reservation cancellation message to the node device 2b in the message processing unit 233. The transmitted bandwidth reservation cancellation message is sent to the node device 2d following the reverse flow of the bandwidth reservation activation cancellation message.

  As described above, according to the method shown in the embodiment of the present invention, the communication network secures a band based on the band information transmitted from the user's terminal device, and the contents having the same content ID are the same. It is possible to realize a traffic engineering multicast distribution method and system that secures a route to be used as a route.

  Further, according to the present invention, the operation of the above-described node device can be constructed as a program, installed in a computer used as the node device, executed, or distributed via a network.

  Further, the constructed program can be stored in a portable storage medium such as a hard disk, a flexible disk, or a CD-ROM, and installed in a computer or distributed.

  The present invention is not limited to the above-described embodiment, and various modifications and applications can be made within the scope of the claims.

  The present invention is applicable to a content distribution technique in a multicast network.

It is a figure for demonstrating the principle of this invention. It is a principle block diagram of this invention. 1 is a system configuration diagram according to an embodiment of the present invention. It is a figure which shows the connection and function of the system in one embodiment of this invention. It is a detailed block diagram of the node apparatus in one embodiment of this invention. It is a block diagram of the message receiving part of the node apparatus in one embodiment of this invention. It is outline | summary explanatory drawing of the process of the band ensuring in one embodiment of this invention. It is a sequence chart of the band ensuring process in one embodiment of this invention in one embodiment of this invention. It is an outline explanatory view in case there is participation afterward in one embodiment of the present invention. It is a sequence chart of a process in case there exists participation afterward in one embodiment of this invention. It is outline | summary explanatory drawing in case there exists detachment | leave in one embodiment of this invention. It is a sequence chart of processing when there is separation in an embodiment of the present invention. It is explanatory drawing of the conventional path | route setting.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Core network 2 Node apparatus 3 Program guide server apparatus 4 Access network 5 User's terminal device 6 Content transmission apparatus 7 Node apparatus 8 User's terminal apparatuses 11-14 Line / LSP
DESCRIPTION OF SYMBOLS 21 Packet distribution part 22 Message transmission / reception part 23 Multicast control part 24 Network information storage part 51 Multicast group participation message transmission part 52 Multicast group leaving message transmission part 231 Participation message response part 232 Message processing part 233 Message processing part 234 Path bandwidth reservation process Unit 235 route band release processing unit 2211 multicast group join message receiving unit 2212 multicast tree setting request message sending unit 2213 multicast tree setting request receiving unit 2214 multicast group leaving message receiving unit 2215 multicast tree release request message sending unit 2216 multicast tree release request message Receiving unit 2217 Band securing activation message sending unit 2218 Band Reservation activation message receiving unit 2219 Band ACK message sending unit 2220 Band reservation message receiving unit 2221 Band reservation activation cancellation message sending unit 2222 Band reservation activation cancellation message receiving unit 2223 Band reservation cancellation message sending unit 2224 Band reservation cancellation message receiving unit 2224
2341 Route calculation processing unit

Claims (10)

A traffic engineering multicast distribution method in a system including a communication network, a plurality of node devices constituting the communication network, a content transmission device connected to any of the node devices, and at least one user terminal device There,
In the node device,
When a multicast group participation message including a content ID for identifying content to participate in a multicast group, bandwidth information, and a multicast group address is received from the user terminal device, a multicast tree setting request message including the content ID is received. A multicast tree setting request message sending step for sending;
In a node device connected to the content transmission device,
When the multicast tree setting request message is received, a route calculation means for calculating a route in which a plurality of LSPs (Label Switched Paths) set for distribution are the same route calculates a route of the distribution tree, and the calculated route and bandwidth information A path bandwidth securing processing step for creating a bandwidth securing activation message including:
A message processing step of sending the bandwidth securing activation message to a downstream node;
A traffic engineering multicast distribution method characterized in that: In the route bandwidth securing processing step,
If there is no content ID that is the same as the content ID included in the multicast tree setting request message in the content that has already been sent, the route calculated by referring to the network information stored in the storage means and the bandwidth information are Create a band securing start message including
When there is a content ID that is the same as the content ID included in the multicast tree setting request message in the content that has already been sent, the network information stored in the storage means is referred to and the route of the content that has already been sent If there is an empty band corresponding to the band indicated in the band information, create a band securing activation message including the same path as the content that has already been transmitted.
The traffic engineering multicast distribution method according to claim 1. In the route bandwidth securing processing step,
When there is a content ID that is the same as the content ID included in the multicast tree setting request message among the content that has already been sent, the route calculation means refers to the network information in the storage means and has already been sent. If there is no empty band for the band indicated in the band information in the content path, the path with the empty band that can secure the band of the content that has already been transmitted and the band indicated in the band information is selected. , Calculate with reference to the network information, create a bandwidth securing activation message including the calculated route,
Create a bandwidth reservation activation cancellation message that releases the LSP of the distribution tree of the content that has already been secured,
In the message processing step,
The traffic engineering multicast delivery method according to claim 1 or 2, wherein the bandwidth reservation activation message and the bandwidth reservation activation cancellation message are transmitted. A traffic engineering multicast distribution system including a communication network, a plurality of node devices constituting the communication network, a content transmission device connected to any of the node devices, and at least one user terminal device,
The node device is
Storage means for storing network information;
A route calculating means for calculating a route in which a plurality of LSPs (Label Switched Paths) set for distribution are the same route with reference to the storage means;
When a multicast group participation message including a content ID for identifying content to participate in a multicast group, bandwidth information, and a multicast group address is received from the user terminal device, a multicast tree setting request message including the content ID is received. A multicast tree setting request message sending means for sending;
When the node device is a node device connected to the content transmission device, when the multicast tree setting request message is received, a bandwidth for creating a bandwidth securing activation message including the route and bandwidth information calculated by the route calculation means A secure start message creating means, a route bandwidth securing processing means,
Message processing means for sending the bandwidth securing activation message to a downstream node;
A traffic engineering multicast distribution system comprising: The route bandwidth securing processing means includes
If there is no content ID that is the same as the content ID included in the multicast tree setting request message in the content that has already been sent, the route calculated by referring to the network information stored in the storage means and the bandwidth information A means for creating a bandwidth securing start message including
When there is a content ID that is the same as the content ID included in the multicast tree setting request message in the content that has already been sent, the network information stored in the storage means is referred to and the route of the content that has already been sent When there is an empty band corresponding to the band indicated in the band information, a means for creating a band securing activation message including the same route as the content route that has already been transmitted;
The traffic engineering multicast distribution system according to claim 4, comprising: The route bandwidth securing processing means includes
If there is a content ID that is the same as the content ID included in the multicast tree setting request message in the already sent content, the route calculation means refers to the network information in the storage means and has already been sent. If there is no empty band for the band indicated in the band information in the content path, a path with an empty band that can secure the band of the content that has already been transmitted and the band indicated in the band information is selected. Means for referring to the network information and calculating a bandwidth securing activation message including the calculated route;
Creating a bandwidth reservation activation cancellation message for releasing the LSP of the distribution tree of the content that has already been secured that has been secured,
The message processing means includes
6. The traffic engineering multicast distribution system according to claim 4 or 5, further comprising means for sending the bandwidth reservation activation message and the bandwidth reservation activation cancellation message. A node device in a system including a communication network, a plurality of node devices constituting the communication network, a content transmission device connected to any of the node devices, and at least one user terminal device,
Storage means for storing network information;
A route calculating means for calculating a route in which a plurality of LSPs (Label Switched Paths) set for distribution are the same route with reference to the storage means;
When a multicast group participation message including a content ID for identifying content to participate in a multicast group, bandwidth information, and a multicast group address is received from the user terminal device, a multicast tree setting request message including the content ID is received. A multicast tree setting request message sending means for sending;
When the node device is a node device connected to the content transmission device, when the multicast tree setting request message is received, a bandwidth for creating a bandwidth securing activation message including the route and bandwidth information calculated by the route calculation means A secure start message creating means, a route bandwidth securing processing means,
Message processing means for sending the bandwidth securing activation message to a downstream node;
A node device comprising: The route bandwidth securing processing means includes
If there is no content ID that is the same as the content ID included in the multicast tree setting request message in the content that has already been sent, the route calculated by referring to the network information stored in the storage means and the bandwidth information A means for creating a bandwidth securing start message including
When there is a content ID that is the same as the content ID included in the multicast tree setting request message in the content that has already been sent, the network information stored in the storage means is referred to and the route of the content that has already been sent When there is an empty band corresponding to the band indicated in the band information, a means for creating a band securing activation message including the same route as the content route that has already been transmitted;
The node device according to claim 7, comprising: The route bandwidth securing processing means includes
When there is a content ID that is the same as the content ID included in the multicast tree setting request message among the content that has already been sent, the route calculation means refers to the network information in the storage means and has already been sent. If there is no empty band for the band indicated in the band information in the content path, the path with the empty band that can secure the band of the content that has already been transmitted and the band indicated in the band information is selected. Means for referring to the network information and calculating a bandwidth securing activation message including the calculated route;
Means for creating a bandwidth reservation activation cancellation message for releasing the LSP of the distribution tree of the content that has already been secured,
The message processing means includes
9. The node device according to claim 7, further comprising means for transmitting the bandwidth securing activation message and the bandwidth securing activation cancellation message. Computer
A traffic engineering multicast distribution program that functions as the node device according to claim 7.

Images