JP4507400B2 - Network resource reservation method and node device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a network resource reservation method and a node device.
[0002]
[Prior art]
Conventionally, when transferring a data stream such as voice and image over an IP network, a certain method for reserving network resources by an application of the communication service has been applied. As such a reservation method, RSVP (Resource Resevation Protocol) method and recommendation of a method for concluding SLA (Service Level Agreement) using COPS (Common Open Policy Service) in a network that supports Diffserv (Differentiated Service) are proposed. It is being advanced.
[0003]
For example, in the RSVP method, all the routers manage resources reserved (occupied) on the Internet in units of data streams. Reserving resources in order to send a data stream to the network using the Diffserv method is close to the conventional reservation method using a dedicated line.
[0004]
[Problems to be solved by the invention]
However, according to the above-described conventional network resource reservation method, there are the following problems.
[0005]
In the RSVP method, when the network becomes large and the number of data streams flowing therethrough becomes enormous, the load for managing resources in each router increases. For this reason, the RSVP method is generally not used much.
[0006]
In addition, as described above, the method of reserving resources in order to send the data stream to the network by the method using Diffserv becomes an image close to the conventional dedicated line, so that the network resources cannot be used effectively or there are There may be a case where the resource reserved by the application cannot be secured during communication.
[0007]
Therefore, there is a need for a network resource reservation method and a node device that can reduce the resource management load on the network elements, can effectively use the network resources, and can keep the reserved resources during communication.
[0008]
[Means for Solving the Problems]
In order to solve such a problem, the first aspect of the present invention is a network resource reservation method for reserving resources for a network in which one or more node devices intervene in data transfer between a first terminal device and a second terminal device. (1) The first terminal device sends a request message for requesting resource reservation, which includes identification information of the source and destination of the transfer data, the service type of the transfer data, and the required resource amount. (2) For each output interface, and for each service type, each of the node devices sets a set bandwidth representing an allowable resource amount, and the provisional reservation and main reservation resource amounts currently allocated. When the request message is received, the output interface is determined based on the destination identification information included in the request message. Constant, and used to determine on the basis of an output interface that this particular, to the service type included in the request message received Pipe Determine the resource information and determine whether or not the resource can be reserved. When the resource can be reserved, the resource amount of the temporary reservation is increased by the resource amount included in the received request message, and the request message is sent to the next device. (Hereinafter referred to as the next device or the previous device in accordance with the flow of the request message), and when the resource cannot be reserved, the identification information of the source and destination of the transfer data, the transfer data A response message including a service type, a necessary resource amount, and reservation rejection is transmitted. (3) When the second terminal device receives the request message, it determines whether or not it can respond to data communication. When it is determined and responds to data communication, the previous device includes the identification information of the source and destination of the transfer data, the service type of the transfer data, the required resource amount, and the reservation possibility. When the response message is sent and the data communication cannot be accepted, the previous device is notified of the identification information of the source and destination of the transfer data, the service type of the transfer data, the required resource amount, and the reservation failure. (4) When each of the node devices receives the response message, the node device specifies the output interface based on the identification information of the transmission destination included in the response message, and this specification The management information to be updated is determined based on the received interface and the service type included in the received response message, and the received response message can be reserved , Constant Received the amount of the booked management information response The resource amount included in the message is increased and a response message indicating that reservation is possible is sent to the previous device. When the received response message is a reservation failure, the provisional resource amount of the provisional management information is received. response Decrease the resource amount included in the message and send a reservation rejection response message to the previous device. (5) The first terminal device recognizes whether or not the resource could be reserved by the received response message. It is characterized by doing.
[0009]
Further, according to the second aspect of the present invention, in the node device intervening in the data transfer between the first terminal device and the second terminal device, (1) permissible resources for each output interface and for each service type It manages the set bandwidth that represents the amount, and the resource amounts of the provisional reservation and the main reservation that are currently allocated, identification information of the transmission data source and destination, the service type of the transfer data, and necessary resources When a request message for requesting resource reservation is received, the output interface is specified based on the identification information of the destination included in the request message, and the specified output interface is received. Used for judgment based on the service type included in the request message Pipe Determine the logical information, determine whether the resource can be reserved, and when it can be reserved, update the temporary reservation resource amount by the resource amount included in the received request message, and (Hereinafter referred to as the next device or the previous device in accordance with the flow of the request message), and when the resource cannot be reserved, the identification information of the source and destination of the transfer data to the previous device, A request message processing means for transmitting a response message including a service type of transfer data, a necessary resource amount, and reservation rejection; and (2) transmission included in the response message when the response message is received. The output interface is identified based on the previous identification information, and this identified interface and the service included in the received response message It defines the management information to be updated on the basis of a separate, when the received response message is a reservation accepted , Constant Received the amount of the booked management information response The resource amount included in the message is increased and a response message indicating that reservation is possible is sent to the previous device. When the received response message is a reservation failure, the provisional resource amount of the provisional management information is received. response Response message processing means for reducing the amount of resources included in the message and transmitting a reservation rejection response message to the previous device.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
(A) First embodiment
Hereinafter, a first embodiment in which a network resource reservation method and a node device according to the present invention are applied to a network that supports a Diffserv function will be described in detail with reference to the drawings.
[0011]
(A-1) Configuration of the first embodiment
FIG. 1 is a block diagram showing devices constituting the network system 100 according to the first embodiment.
[0012]
The network system 100 according to the first embodiment includes a terminal device 110 that is a terminal element of a network, a node device (hereinafter referred to as an edge node device) 120 that accommodates the terminal device 110, and an edge node device 120. A node device (hereinafter referred to as a core node device) 130 intervening in communication. Note that the network connection form may be one in which a plurality of node devices 120 and 130 are connected in a mesh shape, a ring shape, a bus shape, or the like. Also, the communication may be the edge node device 120 in communication with the same node device, and the core node device 130 in other communication. For example, the node devices 120 and 130 correspond to routers.
[0013]
The terminal device 110 includes various application units 111 that provide specific communication services, a reservation management unit 112 that performs reservation processing for network resources necessary for the application units, and a transfer management unit that transfers data generated by the communication services to the edge node device 120 119. Although a plurality of communication services can be arbitrarily implemented in the user terminal device 110, one communication service will be described below.
[0014]
The edge node device 120 includes a network resource reservation management unit 122, a resource management unit 123 that manages resource status, a resource management data table 124 that is used for management by the resource management unit 123, and reception of communication requests from the terminal device 110. A reception management unit 125 that performs management, a reception management data table 126 that the reception management unit 125 uses for reception management, and a transfer management unit 129 that manages data transfer.
[0015]
The core node device 130 includes a reservation management unit 132, a resource management unit 133, a resource management data table 134, and a transfer management unit 139, and the components having the same names as the components of the edge node device 120 Performs a similar function.
[0016]
Reservation management units 122 and 132 are reservation management units 112, 122, and 132 of devices 110, 120, and 130 that should be adjacent on the data transfer path, ICMP (Internet Control Message Protocol), TCP (Transmission Control Protocol), and the like. A predetermined message is exchanged according to a protocol, and network resource reservation control and release control are performed in cooperation.
[0017]
The reservation managers 122 and 132 have reservation states of “START”, “Waiting for reservation”, “Preliminary reservation”, “Reservation OK”, and “Reservation NG”, and the transition between these states is shown in FIGS. As shown.
[0018]
As shown in FIG. 2, only the transition from the “START” state to the “waiting for reservation” state is possible, and the transition from the “waiting for reservation” state to the own state or “provisionally reserved” state is possible. Yes, it is possible to transition from the “provisional reservation” state to the “reservation OK” state or the “reservation NG” state, and the “reservation NG” state. From Only the transition to the “reservation waiting” state is possible, and the transition from the “reservation OK” state to the “reservation waiting” state or the “reservation NG” state is possible.
[0019]
In FIG. 3, the five states described in the vertical direction indicate the state before the transition, the five states described in the horizontal direction indicate the state after the transition, and the transition condition is described in the intersection column. is doing. Note that “MSG” in FIG. 3 represents a message.
[0020]
The specific contents of the state transition will be clarified in the operation description to be described later.
[0021]
The resource managers 123 and 133 manage resources using the resource management data tables 124 and 134. The resources managed by the resource management units 123 and 133 are, for example, resources from the own node (which may include the data output configuration of the own node) to the devices 110, 120, and 130 adjacent in the data transfer direction.
[0022]
FIG. 4 is an explanatory diagram showing the configuration of the resource management data tables 124 and 134. The resource management data tables 124 and 134 are provided for each communication service type “service type (ST)” provided by the nodes 120 and 130. The resource management data tables 124 and 134 are output corresponding to each service type (ST). interface “Interface-ID (OLID)” for identifying the resource, “temporary reserved resource amount (PingW)” indicating the amount of resources being temporarily reserved, and “reserved resource amount (PedW)” after the actual reservation (reservation confirmed) Applicable to network administrators interface Has a “set bandwidth (SW)” that represents the amount of resources allocated to.
[0023]
The reception management unit 125 provided only in the edge node device 120 performs reception management such as managing traffic of each terminal device 110 using the reception management data table 126. Note that the reception management unit 125 of the edge node device 120 of the reservation source (data transfer source) functions effectively, and the reception management unit 125 of the edge node device 120 of the data transfer destination side performs the reception management related to the resource reservation surface. Do not execute.
[0024]
FIG. 5 is an explanatory diagram showing the configuration of the reception management data table 126. The reception management data table 126 is associated with each of a plurality of identifiers “User-ID (UID)” for identifying the user of the application, “reserved resource amount (PedW)” reserved by the application, and “reserved by the application” Service type (ST) ".
[0025]
(A-2) Operation of the first embodiment
Next, a resource reservation operation in the network system 100 of the first embodiment will be described.
[0026]
(A-2-1) Basic technical concept of operation
First, the basic technical concept of the resource reservation operation in the network system 100 of the first embodiment will be described with reference to FIG. In FIG. 6, the edge node device 120A, the core node device 130, and the edge node device 120B perform data transfer from the data transfer source (resource reservation source) terminal device 110A to the data transfer destination terminal device 110B in this order. The case of intervening (relaying) is shown. In the following description, the data transfer source side is expressed as upstream, and the data transfer destination side is expressed as downstream.
[0027]
The resource reservation source terminal device 110A makes a resource reservation by notifying the accommodated edge node device 120A of information such as a required resource amount (reserved resource amount) and a data transfer destination.
[0028]
Each node device 120A, 130, 120B that should intervene in data transfer (relay processing) determines whether or not it can accept a resource reservation request from an upstream device. After the node is temporarily reserved, resource reservation is performed for a downstream device.
[0029]
As described above, if each node device 120A, 130, 120B is in a state where resource reservation is possible, the resource reservation requests are sequentially propagated and reach the terminal device 110B as the data transfer destination.
[0030]
The data transfer destination terminal device 110B receives the resource reservation request and, if it can respond, returns a reservation response to the edge node device 120B.
[0031]
In each node device 120B, 130, 120A, when receiving a reply of a reservation response that can accept a resource reservation from a downstream device, a reservation response that allows the upstream device to accept a resource reservation after setting its own node to a fully reserved state. The Send back.
[0032]
When the resource reservation source terminal device 110A receives a reply to the reservation response that can accept the resource reservation, the terminal device 110A recognizes this and starts data transfer.
[0033]
If each node device 120B, 130, 120A or terminal device 110B cannot accept a resource reservation request from an upstream device, the node device 120B, 130, 120A or terminal device 110B does not place its own node in a provisional reservation state, Without making a resource reservation, it sends back to the upstream device that it cannot be accepted.
[0034]
When each node device 120B, 130, 120A receives a reply indicating that it cannot accept the resource reservation from the downstream device, it returns the own node from the temporary reservation state to the reservation standby state, and accepts the resource reservation to the upstream device. Give a reply to the effect.
[0035]
The resource reservation source terminal device 110A recognizes this by replying that it cannot accept the resource reservation, and waits for data transfer.
[0036]
Even if there is no core node device 130, there are two or more core node devices 130, or even when the terminal devices 11A and 110B are accommodated in the same edge node device 120, the above-described technical concept. The resource reservation process is executed while following the above.
[0037]
Hereinafter, resource reservation processing in each of the devices 110A, 110B, 120A, 120B, and 130 will be described in detail.
[0038]
In the following description, a message from upstream to downstream is referred to as a “temporary reservation message”, and a message from downstream to upstream is referred to as a “reservation response message”.
[0039]
The data part of the “provisional reservation” message includes “stream transmission source ID”, “stream transmission destination ID” by IP address + port number, etc., “service type” of the network requested by the application to the network, Network “resource amount”.
[0040]
The “reservation response” message includes an IP address + port number, etc., “stream transmission source ID”, “stream transmission destination ID”, network “service type” requested by the application, and application requested Includes “resource amount” and “reservation availability” of the network.
[0041]
(A-2-2) Operation of resource reservation source terminal device 110A
First, the operation in the resource reservation source terminal device 110A will be described with reference to FIG. FIG. 7 is a flowchart showing the operation as the terminal device 110 (110A, 110B). Steps ST11 to ST16 indicate processing of the resource reservation source terminal device 110A, and steps ST13, ST14, and ST17 to ST19 are steps. The operation | movement of the terminal device 110B facing the terminal device 110A is shown.
[0042]
In terminal apparatus 110A, as shown in FIG. 7, when a communication service is activated in application unit 111, the user specifies an arbitrary network service and network resource and designates necessary parameters (ST11). If there is no user designation, the application unit 111 may automatically determine a required parameter, or may be set with a starting condition from a predetermined initial value.
[0043]
When these setting parameters are notified, the reservation management unit 112 organizes a “temporary reservation” message of the network resource and transmits it to the reservation management unit 122 of the edge node device 120A (ST12). And secure the completion through the edge node device 120A Notice Wait until a “reservation response” message can be received (ST13). By transmitting the “provisional reservation” message in step ST12, the terminal device 110A has requested the reservation (reservation) of the resource over the entire network up to the opposite terminal device 110B.
[0044]
When the reservation is completed in each of the edge node device 120A, the core node device 130, the edge node device 120B, and the opposite terminal device 110B, which will be described later, a “reservation response” message indicating OK (possible) is returned via the edge node device 120A. Is done. On the other hand, the edge node device 120A, the core node device 130, the edge node device 120B, Or When the opposing terminal device 110B cannot accept the resource reservation, a “reservation response” message indicating NG (not) started to be sent upstream from the device is returned.
[0045]
Recognizing that the received message is a “reservation response” message (see ST14), terminal apparatus 110A determines the “possibility status” of the reservation included in this message (ST15), and if “OK”, The resource condition based on the parameter is notified to the transfer management unit 129 and the reservation completion is notified to the application unit 111, respectively.
[0046]
The application unit 111 approves the tentative reservation, declares the reservation completion, that is, the main reservation, notifies the transfer management unit 119 of this, and starts data transmission. For example, the transfer management unit 113 transfers the stream data from the application unit 111 to the transfer management unit 129 of the edge node device 120 based on the resource condition specified by the reservation management unit 112 (ST16).
[0047]
If the availability status of the received “reservation response” message is “NG”, this is notified to the application unit 111, and in either case, it waits until the user designates the parameter again (ST13).
[0048]
(A-2-3) Operation of edge node device 120A, 120B
In the edge node devices 120A and 120B, as shown in the flowchart of FIG. 8, the reservation management unit 122 changes the resource reservation process depending on the type of message that has arrived in “waiting to receive a message (MSG)” (ST21).
[0049]
(A-2-3-1) Operation for provisional reservation message
When the reservation management unit 122 receives a “provisional reservation” message for a resource from the upstream terminal device 110A or the core node device 130 (ST22), a reservation is possible from the management status by the resource management unit 124 of the own node device 120A, 120B. Is determined (ST23).
[0050]
If reservation is possible, the own node apparatuses 120A and 120B are shifted to the “provisional reservation” state, the resource management unit 123 executes the resource temporary reservation process, and the downstream apparatuses 130 and 110B also execute “ A “provisional reservation” message is transmitted (ST24, ST25). On the other hand, if the reservation is not possible, a reservation response message indicating reservation NG is formed as “permitted status” and sent to the upstream devices 110A and 130 (ST26).
[0051]
Hereinafter, the processing of steps ST23 to ST26, particularly the processing of step ST23, will be described in detail.
[0052]
When the “provisional reservation” message is received, the reservation management unit 122 notifies the resource management unit 123 of the “service type”, “resource amount”, and “stream destination ID” specified in the “provisional reservation” message content. . In response to this, the resource management unit 123 acquires an interface number (interface ID) to be a transfer route from the transfer management unit 129 to the “stream transmission destination ID”.
[0053]
Further, based on the setting contents of the resource management data table 124, it is determined by the following arithmetic expression <1> whether or not the resource amount specified for the service type can be used.
[0054]
Ping [i] + R <SW [i] ... <1>
i is a parameter for specifying an interface, 1 ≦ i ≦ n (n is the number of interfaces), Ping [i] is the amount of temporary reservation resources in the i-th interface, and R is a “provisional reservation” message. SW [i] is a resource amount (set bandwidth) allocated in advance for each link of the node device.
[0055]
When this calculation formula <1> is satisfied, a new temporary reserved resource amount Ping [i] is calculated by the following calculation formula <2> and the resource management data table 124 is updated. This Provisional The reserved resource amount Ping is updated.
Ping [i] = Ping [i] + R ... <2>
[0056]
Ping [i] = Ping [i] + R ... <2>
Further, the reservation management unit 122 is notified that temporary reservation is possible, and a “provisional reservation” message is transmitted to the downstream devices 130 and 110B (next HOP).
[0057]
However, if the arithmetic expression <1> is not satisfied, the reservation management unit 122 is notified that the reservation is not possible, and the “reservation response” message with “NG” is set to NG is sent to the upstream devices 110A and 130 (previous HOP). ).
[0058]
(A-2-3-2) Operation for reservation response message
When the reservation management unit 122 receives the resource “reservation response” message from the downstream terminal device 110B or the core node device 130 (ST22), it determines the “permitted / not-permitted state” included in the “reservation response” message (ST33). ). If the “permission status” is OK, resource reservation processing is performed in cooperation with the resource management unit 123 and the reception management unit 125 (ST34; this sets the next reservation wait state). "OK" transmits a "reservation response" message to the upstream apparatuses 110A and 130 (previous HOP) (ST35). On the other hand, if the “acceptability state” message of NG “reservation response” is received, after canceling the temporary reservation of the resource in cooperation with the resource management unit 123 (ST36; In the reservation waiting state), a “reservation response” message with “NG” is sent to the upstream devices 110A and 130 (previous HOP) (ST37).
[0059]
The resource reservation process (ST34) and the resource temporary reservation cancellation process (ST36) will be described in detail. The reservation management unit 122 notifies the resource management unit 123 of “availability state”, “stream destination ID”, “service type”, and “resource amount” included in the “reservation response” message. The resource management unit 123 that has received the notification specifies an interface number (interface ID “i”) to be the transfer route of the stream from the transfer management unit 129 based on the “stream destination ID”.
[0060]
In the resource reservation process, the reservation resource amount designated for the service type is updated by the following arithmetic expression <3>, and the reservation management unit 122 is notified that the reservation is completed.
[0061]
Ped [i] = Ped [i] + R ... <3>
Ped [i] is the reserved resource amount in the i (1 ≦ i ≦ n) -th interface, and R is the resource amount specified in the “reservation response” message.
[0062]
If the edge node device is the edge node device 120A that accommodates the reservation source terminal device 110A, the “reservation response” message “stream transmission source ID”, “service type”, and “resource amount” are accepted. The management unit 125 is notified, and “stream transmission source ID” is registered in the User-ID of the reception management data table 126, “resource amount” is registered in the reserved resource amount, and “service type” is registered in the reserved service type.
[0063]
Furthermore, the reservation management unit 122 transmits an “OK” “reservation response” message to the upstream devices 110A and 130. The transfer management unit 129 performs data transfer while monitoring traffic based on the updated reception management data table 126, and appropriately discards or marks the violated data.
[0064]
On the other hand, in the resource temporary reservation cancellation process (ST36), the temporary reserved resource amount is returned to the original by the following arithmetic expression <4>.
[0065]
Ping [i] = Ping [i] -R ... <4>
R is the resource amount specified by the “reservation response” message.
[0066]
In addition, the reservation management unit 122 transmits a “reservation response” message with “NG” as “NG” to the upstream apparatuses 110 </ b> A and 130.
[0067]
(A-2-4) Operation of the core node device 130
The core node device 130 performs the same operation as the edge node devices 120A and 120B except for the operation of the reception management unit 125 (see FIG. 8).
[0068]
(A-2-5) Operation of opposing terminal apparatus 110B
As described above, steps ST13, ST14, and ST17 to ST19 in FIG. 7 show the operation of the terminal device 110B facing the reservation-source terminal device 110A.
[0069]
In the terminal device 110B facing the reservation-source terminal device 110A, the reservation management unit 112 can receive only the resource “provisional reservation” message (ST13, ST14), and receives the “provisional reservation” message from the edge node device 120B. Then, the state of the application unit 111 is confirmed based on the “stream transmission destination ID” (ST17), and if data can be received, a “reservation response” message with “OK” is formed and an edge is formed. On the other hand, if data cannot be received, a “reservation response” message with “NG” is “NG” is formed and transmitted to the edge node device 120B (ST19).
[0070]
(A-2-6) Canceling temporary reservation due to timeout
Further, although illustration of the flowchart is omitted, the node devices such as the edge node devices 120A and 120B and the core node device 130 time a predetermined time after sending the “provisional reservation” message to the downstream, If a “reservation response” message is not received from the downstream side even after a predetermined time has elapsed, the temporary reservation state is canceled, and a “reservation response” message with “NG” being “NG” is formed to the upstream side. Send.
[0071]
Similarly, the resource reservation source terminal device 110A counts a predetermined time after sending the “provisional reservation” message to the edge node device 120A. When the “reservation response” message is not received from the node device 120A, it is considered that the resource reservation has failed.
[0072]
(A-3) Effects of the first embodiment
According to the first embodiment, the resource reserved by the application unit 111 of the terminal device 110A is managed by the user data flow unit by the “User-ID” in the edge node device 120A. Whether or not the resource is to be used beyond the reserved bandwidth can be monitored and controlled by the edge node device 120A.
[0073]
In addition, the resources to be managed in the network are the flow units between the user terminal devices 110A and 110B and the edge node devices 120A and 120B, between the edge node devices 120A and 120B and the core node device 130, and the core node device 130. Since the service type unit that flows on each link is set between each other, the number of states that must be managed by each of the node devices 120A, 120B, 130,... Can be greatly reduced. Can be reduced.
[0074]
Further, in each of the node devices 120A, 120B, 130,..., When determining whether or not the resource can be reserved, the calculation has been performed in consideration of the bandwidth “reserved”. It will never happen. As a result, resources reserved by a certain application can be kept during communication, and efficient use of network resources can be realized.
[0075]
(B) Second embodiment
Hereinafter, a second embodiment in which the network resource reservation method and the node device according to the present invention are applied to a network that supports the Diffserv function will be described in detail with reference to the drawings.
[0076]
The first embodiment is an embodiment related to a resource reservation process, but the second embodiment is related to a reserved resource release process. The resource releasing process according to the second embodiment is not limited to the resource reserved according to the first embodiment, but it is preferable that the resource is reserved according to the first embodiment.
[0077]
(B-1) Configuration of the second embodiment
The configuration of the network system of the second embodiment can also be represented in FIG. 1 according to the first embodiment described above. That is, a terminal device 110, an edge node device 120 that accommodates the terminal device 110 and releases reserved resources on the network, and one or more core node devices 130 that are interposed between the edge node devices 120 and release reserved resources. Have.
[0078]
In the case of this second embodiment, between the adjacent devices, instead of the “provisional reservation” and “reservation response” messages of the first embodiment, the resource “release request” and “release response” messages are sent. Forward.
[0079]
In the case of the second embodiment, the reservation managers 122 and 132 of the node devices 120 and 130 are in the states of “START”, “Waiting for release”, “Under release”, “Release OK”, and “Release NG”. The transition between these states is as shown in FIGS. Although there is a difference between resource reservation and resource release, these state transitions are the same as in the first embodiment.
[0080]
(B-2) Operation of the second embodiment
Next, a resource releasing operation in the network system 100 according to the second embodiment will be described.
[0081]
(B-2-1) Basic technical concept of operation
As shown in FIG. 11, the resource release operation in the network system 100 of the second embodiment is also performed by sending the release request message from the terminal device 110A in the order of the edge node device 120A, the core node device 130, and the edge node device 120B. When the terminal device 110B executes the resource release processing, the release response message is sent back to the edge node device 120B, the core node device 130, and the edge node device 120A. In this order, the resource is released in all network element devices.
[0082]
Hereinafter, resource reservation cancellation in each of the devices 110A, 110B, 120A, 120B, and 130 will be described in detail.
[0083]
In the data part of the “release request” message, “stream transmission source ID”, “stream transmission destination ID” by IP address + port number, etc., “service type” reserved for the network by the application, and application reserved "Resource amount" included.
[0084]
The “release response” message includes “stream transmission source ID”, “stream transmission destination ID” by IP address + port number, “service type” reserved for the network by the application, and “resources” reserved by the application. Amount ”and“ cancellation status ”.
[0085]
(B-2-2) Operation of terminal devices 110A and 110B
First, the operation of the terminal device 110A will be described. When the user of the terminal device 110A terminates the application unit 111, the user instructs the cancellation of the network service and network resources used by the application unit 111, and the terminal device 110A sets parameters for cancellation (ST41). . When the user does not select a parameter for the reserved resource, the terminal device 110A autonomously performs it. Then, terminal device 110A transmits a “cancel request” message to edge node device 120A (ST42).
[0086]
The terminal device 110A then waits for a “release response” message from the edge node device 120A as a response (ST43). When the terminal device 110A receives the “release response” message (ST44), it is included in the “release response” message. The “permitted / unavailable state” of the release being released is determined (ST46). If the “OK / NG state” is “OK”, this is notified to the application unit and the process ends normally. If “NG”, this is notified to the application unit and a predetermined NG process is performed (ST47). The predetermined NG process is, for example, a process for resending a “cancel request” message after a predetermined time.
[0087]
On the other hand, the opposite terminal apparatus 110B is in a reception waiting state for the “release request” message (ST44). Upon receiving the “release request” message, the application unit identifies the communication service corresponding to the “stream destination ID”. Then, the application unit terminates the corresponding service, forms a “release response” message with “OK” as “OK”, and transmits it to the edge node device 120B (ST45).
[0088]
(B-2-3) Operation of each node device
Each node device 120A, 130, 120B performs a similar resource release operation. Note that the edge node device 120A that accommodates the terminal device 110A performs processing in the reception management unit 125 in addition to the same processing as the other node devices 120B and 130.
[0089]
Hereinafter, the operation of each of the node devices 120A, 130, 120B will be described with reference to the flowchart of FIG.
[0090]
As shown in FIG. 13, each node device 120A, 130, 120B receives a “release request” message from the upstream device 110A, 120A, 130, or a “release” from the downstream device 130, 120B, 110B. response The message is awaited (ST51), and when the message is received, it is determined which type of message it is (ST52).
[0091]
When the “release request” message is received from the upstream devices 110A, 120A, and 130, a process of releasing the reserved resources to the adjacent downstream devices 130, 120B, and 110B is executed (ST53).
[0092]
In this resource release process, the reservation management unit notifies the resource management unit of the “service type”, “resource amount”, and “stream destination ID” included in the “release request” message, and the resource management unit , An interface number (interface ID) “i” to be a transfer route to “stream transmission destination ID” is acquired. Then, based on the setting contents of the resource management data table, the provisionally reserved resource amount Ping [i] and the reserved resource amount Ped [i] related to the interface number “i” are calculated using the formula <14>. , <15> to notify the reservation manager that resource release is complete. Note that R is the resource amount specified in the “release request” message.
[0093]
Ping [i] = Ping [i] -R ... <14>
Ped [i] = Ped [i] −R... <15>
In the edge node device 120A, “release” is performed as part of the resource release processing. request The reception management unit also deletes the corresponding information from the reception management data table based on the “stream source ID”, “service type”, and “resource amount” of the message.
[0094]
Thereafter, the downstream devices 130, 120B, 110B Release request "Message is transmitted (ST54).
[0095]
On the other hand, when each node device 120A, 130, 120B receives the “release response” message from the downstream devices 130, 120B, 110B, the node device 120A, 130, 120B determines the “possibility state” included in the message (ST55).
[0096]
If this “probability status” is “OK”, a “cancel response” message with “OK” is “OK” is transmitted to the upstream devices 110A, 120A, and 130 (ST56). On the other hand, if “NG”, a predetermined NG process is performed (ST57), and then a “cancel response” message with “NG” is “NG” is transmitted to the upstream devices 110A, 120A, and 130 (ST56). .
[0097]
For example, the NG process is a process for restoring a resource released in response to a “release request” message.
[0098]
Although not shown, each of the node devices 120A, 130, 120B counts a predetermined time after sending a “cancel request” message to the downstream devices 130, 120B, 110B, and within the predetermined time When a “cancel response” message cannot be received, the device performs a predetermined NG process, and then transmits a “cancel response” message with “NG” as “NG” to the upstream devices 110A, 120A, and 130.
[0099]
(B-3) Effects of the second embodiment
Although there is a difference between resource reservation and resource reservation cancellation, the second embodiment can provide the same effects as those of the first embodiment, except for prevention of reservation mismatch.
[0100]
That is, since the resource reserved by the application unit 111 of the terminal device 110A is managed in units of data by the “User-ID” in the edge node device 120A, the resource exceeds the bandwidth reserved by the application unit 111. Whether or not it is going to be used can be monitored and controlled by the edge node device 120A. Further, the resources to be managed in the network are determined in units of flow between the user terminal apparatuses 110A and 110B and the edge node apparatuses 120A and 120B, between the edge node apparatuses 120A and 120B and the core node apparatus 130, and the core node apparatus 130. Since the service type unit that flows on each link is set between each other, the number of states that must be managed by each node device 120A, 120B, 130,... Can be greatly reduced. Can be reduced.
[0101]
(C) Other embodiments
In each of the above embodiments, the case where user data is transmitted in one direction has been described as an example. However, bidirectional transmission / reception may be performed, and multicast may be performed. In the case of bi-directional, for example, when determining whether reservation is possible, determination in the reverse direction may also be performed. When the opposite terminal device receives a “provisional reservation” message, a “reservation complete” message Not only send a "provisional reservation" message in the reverse direction West May be. In the case of multicast, for example, in each node device, it is necessary to appropriately branch a “provisional reservation” message and to appropriately integrate a “reservation complete” message.
[0102]
Further, the network to which the present invention is applicable is not limited, and may be not only the Internet network but also a local area network.
[0103]
【The invention's effect】
As described above, according to the present invention, there is provided a network resource reservation method and a node device that can reduce resource management load in a network element, can effectively use network resources, and can keep reservation resources during communication. realizable.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a system configuration of a first embodiment.
FIG. 2 is an explanatory diagram illustrating an example of a transition state of each node device according to the first embodiment.
FIG. 3 is an explanatory diagram illustrating an example of a transition condition of each node device according to the first embodiment.
FIG. 4 is an explanatory diagram illustrating an example of a resource management data table according to the first embodiment.
FIG. 5 is an explanatory diagram illustrating an example of a reception management data table according to the first embodiment.
FIG. 6 is an explanatory diagram of a concept of resource reservation operation in the first embodiment.
FIG. 7 is a flowchart showing a resource reservation operation in the terminal device of the first embodiment.
FIG. 8 is a flowchart illustrating a resource reservation operation in the node device according to the first embodiment.
FIG. 9 is an explanatory diagram illustrating an example of a transition state of each node device according to the second embodiment;
FIG. 10 is an explanatory diagram illustrating an example of a transition condition of each node device according to the second embodiment.
FIG. 11 is an explanatory diagram of a concept of a reservation resource releasing operation in the second embodiment.
FIG. 12 is a flowchart illustrating a reservation resource release operation in the terminal device according to the second embodiment;
FIG. 13 is a flowchart illustrating a reservation resource release operation in the node device according to the second embodiment;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 100 ... Network system, 110, 110A, 110B ... Terminal device, 111 ... Application part, 112, 122, 132 ... Reservation management part, 119, 129, 139 ... Transfer management part, 120, 120A, 120B ... Edge node apparatus, 123 133 ... Resource management unit 124, 134 ... Resource management data table, 125 ... Reception management unit, 126 ... Reception management data table, 130 ... Core node device.

Claims (4)

In a network resource reservation method for reserving resources for a network in which one or more node devices are interposed in data transfer between a first terminal device and a second terminal device,
The first terminal device sends a request message for requesting resource reservation, which includes identification information of the source and destination of the transfer data, the service type of the transfer data, and the required resource amount,
Each of the node devices manages a set bandwidth representing an allowable resource amount for each output interface and for each service type, and the resource amounts of the temporary reservation and the main reservation allocated at the present time. When the message is received, the output interface is specified based on the identification information of the destination included in the request message, and based on the specified output interface and the service type included in the received request message. Te defining the management information Ru used for the determination, it determines whether the resource can be reserved, when can be reserved, by increasing the resource amount of the resource amount only tentative reservation included in the request message received, A request message is transmitted to the next device (hereinafter referred to as the next device or the previous device according to the flow of the request message), and the resource The when not reserve, in front of the device, the source and destination identification information of the transfer data, service type, resource required transfer data, and sends a response message containing not reserved,
When the second terminal device receives the request message, the second terminal device determines whether or not to accept the data communication. When the second terminal device accepts the data communication, the second device transmits the transmission source and destination of the transfer data to the previous device. When a response message containing identification information, transfer data service type, required resource amount, and reservation availability is sent and data communication is not possible, the source and destination of the transfer data are sent to the previous device. A response message including the identification information, the transfer data service type, the required resource amount, and the reservation rejection,
When each of the node devices receives a response message, the node device identifies an output interface based on the identification information of the transmission destination included in the response message, and is included in the identified interface and the received response message. service type and set the management information to be updated on the basis of, when the received response message is a reservation accepted, the constant meta resource amount that are included in the response message received resource amount of the reservation of the management information are The amount of resources included in the response message that received the provisional reservation resource amount of the specified management information when the response message received is a reservation rejection and the response message received is a reservation rejection And a reservation failure response message is sent to the previous device.
The network resource reservation method according to claim 1, wherein the first terminal device recognizes whether or not the resource can be reserved by the received response message. The first terminal device transmits a release request message for requesting release of resource reservation, including identification information of a source and destination of transfer data, a service type of transfer data, and a necessary resource amount. ,
When each of the node devices receives the release request message, the node device specifies an output interface based on the identification information of the transmission destination included in the release request message, and includes the identified interface and the received release request message. including defines the management information to be updated on the basis of the service being kind, with Ru is decreased by the resource amount that are included in the release request message received resource amount of the reservation management information that defines, determined Decrease the resource amount of the tentative reservation of management information by the resource amount included in the received request message and send the release request message to the next device,
When the second terminal apparatus receives the cancellation request message, the second terminal apparatus cancels the data communication state and sends the transfer data transmission source and transmission destination identification information, transfer data service type, and necessary resources to the previous apparatus. Send a release response message containing the amount and release available,
When each of the node devices receives the release response message, the node device specifies an output interface based on the identification information of the transmission destination included in the release response message, and includes the identified interface and the received release response message. The management information to be updated is determined based on the included service type, and when the received release response message can be released, the release response message that can be released is sent to the previous device, and the received release response message When the cancellation is rejected, the resource amount of the provisional reservation of the defined management information is increased by the resource amount included in the received cancellation response message, and the cancellation response of receiving the resource amount of the reserved reservation of the defined management information is received Increase the amount of resources included in the message and send a cancellation response message to the previous device.
The network resource reservation method according to claim 1, wherein the first terminal device recognizes whether the resource has been released by the received release response message. Each of the above-mentioned node devices is determined when a reservation request message is received from the previous device when a corresponding response message cannot be received after a predetermined time has passed since the reservation request message was transmitted to the next device. Decrease the resource amount of the tentative reservation in the management information by the resource amount included in the received request message, send a reservation rejection response message to the previous device, and send a cancellation request message to the next device From the request message received the provisional resource amount of the management information determined when receiving the release request message from the previous device when the corresponding release response message cannot be received even after a predetermined time The amount of resources included in the cancellation request message that received the reserved resource amount of the specified management information. Network resource reservation method according to claim 2, characterized by sending a release whether the cancellation response message to the device prior to increase. In the node device intervening in the data transfer between the first terminal device and the second terminal device,
For each output interface and for each service type, it manages the set bandwidth that represents the allowable resource amount and the resource amount of the temporary reservation and the main reservation that are allocated at the present time. When receiving a request message for requesting resource reservation, including the identification information of the destination, the service type of the transfer data, and the required resource amount, based on the identification information of the destination included in the request message identify the output interface Te, defines an output interface that this particular, the management information Ru used for the determination on the basis of the service type included in the request message received, to determine whether the resource can be reserved When reservations can be made, an update that increases the resource amount of the tentative reservation by the amount of resources included in the received request message And send a request message to the next device (hereinafter referred to as the next device or the previous device according to the flow of the request message), and when the resource cannot be reserved, A request message processing means for transmitting a response message including identification information of a destination, a service type of transfer data, a necessary resource amount, and reservation rejection;
When the response message is received, the output interface is specified based on the identification information of the destination included in the response message, and based on the specified interface and the service type included in the received response message. Te defines the management information to be updated, when the received response message is a reservation accepted, prior together is increased by the amount of resources that are included in the response message a resource amount of the reservation received constant meta management information When a response message indicating that the reservation is possible is transmitted to the device, and the received response message is a reservation failure, the resource amount of the provisional reservation of the defined management information is reduced by the resource amount included in the received response message and A response message processing means for transmitting a reservation rejection response message to the device. Place.

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