JP2995676B2 - Information communication method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information communication method, and more particularly to an information communication method used for realizing an information communication service for communicating continuous information such as moving image communication.

[0002]

2. Description of the Related Art In continuous media communication for communicating continuous information such as moving image communication, a band-guaranteed transport layer connection for guaranteeing a certain band used for communication in order to satisfy a predetermined communication quality. Or a network layer connection is required. Therefore, when setting up a connection between terminals, it is necessary to secure a predetermined band for each communication line that passes through.

Conventionally, as a method of designating a desired band in each communication line, there are (a) a method of designating only a desired value,
(B) There is a method of designating two sets of a desired value and a minimum value. If the bandwidth that satisfies the required value cannot be secured, (a) the connection setup may be failed due to the busy status, or (b) the connection may be established by securing the bandwidth that can be secured for the time being and the communication may be started. is there. Therefore, as information communication methods used for continuous media communication, there have been various methods in which these (a), (b) and (a) (b) are combined.

[0004] For example, ST2 (In) is a typical example of a layer 3 protocol intended for application to continuous media communication.
Internet STream Protocol Version 2: rfc1819), which is a method combining the above (b) and (a).
In ST2, the application specifies a required communication service quality (QoS) in the form of a flow specification (FlowSpec), and is set in a connection setting packet.
Of the flow specifications, as for the communication band, a desired value and a minimum value can be designated.

[0005] When each relay node up to the destination node receives the connection setup packet, it secures and relays the network resources necessary to realize the QoS described in the flow specification. At this time, the flow specification value is updated and relayed according to the available resource amount. If necessary resources cannot be secured, a connection setting failure packet is transmitted to the source node, and each node returns the secured resources.

[0006]

However, in such a conventional information communication method, of the video coding methods used for moving image communication, applications of a method corresponding to various communication bands from low speed to high speed are used. There was a problem that it could not be used. As an example of a video encoding system capable of adjusting the encoding speed according to the band, ITU-T
Recommendation H. 261 “p × 64 kb / s video coding method for audiovisual communication”. The communication band used in this encoding method is set at 64 kb / s × p (p is an integer of 1 to 30), and moving image communication can be performed with quality according to the available communication band.

However, the above-mentioned conventional methods (a) and (b) cannot effectively utilize the above-described moving picture communication coding schemes corresponding to various communication bands. That is, by applying an encoding method according to the secured band,
Although it is conceivable to realize a communication service of better quality, in (a), since only the desired value is specified, communication cannot be performed if the desired value cannot be secured. In (b), the desired value and the minimum value are specified, but the setting between them is not possible. 2
The coding method such as 61 cannot be used effectively.

[0008] On the other hand, in (b), connection can be set, but there is a possibility that the minimum bandwidth required by the application cannot be guaranteed, and effective communication may not be possible. Further, even if the minimum bandwidth can be secured, there is a possibility that an extra bandwidth may be secured, and effective use of network resources cannot be achieved. Furthermore, the above problem is that the attribute of the connection is two-way data transfer,
There is also a case where the required bandwidth is different for uplink and downlink,
There has been such a problem that an appropriate method for securing the bandwidth has not been established. An object of the present invention is to solve such a problem, and it is an object of the present invention to secure a communication band useful for an application as much as possible and to improve the quality of communication service and effectively use network resources.

[0009]

In order to achieve such an object, an information communication method according to the present invention provides a method for transmitting a request band requested by a higher-order application at a transmission source node.
Based on the minimum bandwidth and the incremental unit bandwidth, of the bandwidth that is equal to or less than the required bandwidth from the unallocated bandwidth of the line with the adjacent node on the destination node side, or the bandwidth that is less than the unallocated bandwidth and increased by the incremental unit bandwidth from the minimum bandwidth The maximum bandwidth that can be reserved is temporarily reserved as the acquisition bandwidth, and the minimum bandwidth, the increment unit bandwidth, and the acquisition bandwidth are notified to the adjacent node on the destination node side by the connection setting request notification, and the relay node transmits the connection setting request notification. Based on the notified minimum bandwidth, increment unit bandwidth, and acquisition bandwidth, the acquisition bandwidth from the unallocated bandwidth of the line with the adjacent node on the destination node side, or the increment from the minimum bandwidth equal to or less than the unallocated bandwidth Temporarily secure the maximum bandwidth that can be secured among the increased bandwidths as the acquisition bandwidth, and connect the minimum bandwidth, incremental unit bandwidth, and acquisition bandwidth to each other. Notify the adjacent node on the destination node side with the setting request notification, and the destination node returns a connection setting response notification including the obtained bandwidth finally notified in the connection setting request notification to the adjacent node on the source node side The relay node releases an extra band among the bands temporarily reserved based on the acquired band notified by the connection setting response notification, and transmits the connection setting response notification to the adjacent node on the source node side. The source node releases the excess bandwidth from the bandwidth temporarily reserved based on the acquisition bandwidth notified by the connection setting response notification, and transmits the connection having the notified acquisition bandwidth to the destination. This is to notify the host application of the setting made with the node. Therefore, at the transmission source node and the relay node, based on the requested bandwidth requested from the upper application or the acquisition bandwidth notified from the adjacent node on the transmission source node side, based on the minimum bandwidth and the incremental unit bandwidth,
The maximum bandwidth that can be secured as the acquisition bandwidth is the required bandwidth from the unallocated bandwidth of the line with the adjacent node on the destination node side, or the bandwidth that is less than the unallocated bandwidth and is increased by the increment unit bandwidth from the minimum bandwidth. An extra band is released from the initially temporarily reserved band based on the final acquired band notified temporarily by the connection setting response notification returned from the destination node.

In another information communication method according to the present invention, in a connection having an attribute of two-way data transfer, a down link from a source node to a destination node and a down connection from a destination node to a source node at a source node. With respect to the upstream connection, of the requested bandwidth, minimum bandwidth and incremental unit bandwidth individually requested from the upper application, based on the required bandwidth for the downlink connection, the minimum bandwidth and the incremental unit bandwidth, with the adjacent node on the destination node side. Of the required bandwidth from the unallocated bandwidth of the line between them, or the bandwidth that is less than or equal to the unallocated bandwidth and increased by the increment unit bandwidth from the minimum bandwidth, and temporarily secures the maximum bandwidth that can be secured as the acquisition bandwidth, and Lowest bandwidth,
The incremental unit bandwidth and the acquisition bandwidth are notified to the adjacent node on the destination node side in the connection setting request notification, and the relay node is configured based on the minimum bandwidth of the downlink connection, the increment unit bandwidth, and the acquisition bandwidth notified in the connection setting request notification. To obtain the maximum bandwidth that can be secured from the unallocated bandwidth of the line with the adjacent node on the destination node side, or the bandwidth that is less than the unallocated bandwidth and that is increased from the lowest bandwidth in increments of unit bandwidth. While temporarily allocating the bandwidth, based on the minimum bandwidth of the uplink connection, the increment unit bandwidth and the acquisition bandwidth, from the unallocated bandwidth of the line to the adjacent node on the source node side to the acquisition bandwidth or below the unallocated bandwidth The maximum bandwidth that can be secured among the bandwidths increased by the increment unit bandwidth from the lowest bandwidth is provisionally secured as the acquisition bandwidth. The minimum bandwidth, incremental unit bandwidth, and acquisition bandwidth of the connection are notified to the adjacent node on the destination node side in the connection setting request notification, and the destination node notifies the minimum bandwidth and incremental unit bandwidth of the uplink connection notified in the connection setting request notification. Based on the acquired bandwidth and the acquired bandwidth, it is possible to secure the bandwidth from the unallocated bandwidth of the line between the source node and the adjacent node to the acquired bandwidth, or the bandwidth that is equal to or less than the unallocated bandwidth and increased by the increment unit bandwidth from the minimum bandwidth Temporarily reserves the maximum bandwidth as an acquisition bandwidth, and sends a connection setting response notification including the final acquisition bandwidth of the uplink connection and the acquisition bandwidth of the downlink connection finally notified in the connection setting request notification to the transmission source node side. The relay node returns to the neighboring node of the In addition to releasing the extra bandwidths among the bandwidths temporarily reserved based on the acquired bandwidth at the beginning, the connection setting response notification is transferred to the adjacent node on the source node side, and the transmission source node Based on the acquired bandwidth of the downlink connection notified by the notification, while releasing the extra bandwidth of the bandwidth of the downlink connection provisionally initially secured, each connection having the notified downlink and uplink acquisition bandwidth is This is to notify the host application of the setting with the destination node. Therefore, at the source node, the relay node, and the destination node, the requested bandwidth individually requested for the downlink / uplink connection from the upper application or the acquisition bandwidth notified from the adjacent node on the source node side;
Based on the minimum bandwidth and the incremental unit bandwidth, the required bandwidth from the unallocated bandwidth of the line to the adjacent node on the destination node side or the line between the adjacent node on the source node side, or less than the unallocated bandwidth The maximum bandwidth that can be secured among the bandwidths increased by the increment unit bandwidth from the minimum bandwidth is provisionally secured as the acquisition bandwidth, respectively, and the final acquisition bandwidth notified in the connection setting response notification returned from the destination node. , An extra band is released from the band temporarily reserved for each connection.

[0011] In addition, as the increment unit band, a band increase determined to be effective for a host application when a band to be secured is increased is set. When the unallocated bandwidth is smaller than the minimum bandwidth at the relay node, the connection setting failure notification is immediately returned to the adjacent node on the transmission source node side, and the provisional reservation is initially made in response to the reception of the connection setting failure notification. Immediately release the reserved bandwidth and immediately transfer this connection setting failure notification to the adjacent node on the source node side. Release the band immediately,
This is to notify the upper application of the connection setting failure. Therefore, in response to the connection setting failure, the bandwidth temporarily reserved in each node is immediately released. If the unallocated bandwidth is smaller than the minimum bandwidth in either the downlink or uplink connection, the relay node and the destination node immediately return a connection setting failure notification to the adjacent node on the source node side, and Upon receiving the setting failure notification, the bandwidth temporarily reserved for each of the downstream and upstream connections is immediately released, and the connection setting failure notification is immediately transferred to the adjacent node on the source node side. However, the source node immediately releases the bandwidth temporarily reserved for each connection in response to the connection setting failure notification, and notifies the upper-level application of the setting failure of both connections. It was done. Therefore,
In response to a connection setting failure occurring in either the downstream or upstream connection, the bandwidth of both connections temporarily reserved in each node is immediately released.

[0012] In addition, when the source node temporarily reserves the required bandwidth from the unallocated bandwidth, if the unallocated bandwidth is equal to or more than the required bandwidth, the required bandwidth is provisionally secured as an acquisition bandwidth. Is smaller than the required bandwidth, the unallocated bandwidth is temporarily reserved as an acquisition bandwidth, and the relay node
When temporarily securing the acquired bandwidth from the unallocated bandwidth, if the unallocated bandwidth is equal to or greater than the acquired bandwidth, temporarily secure the acquired bandwidth as a new acquired bandwidth, and if the unallocated bandwidth is smaller than the acquired bandwidth, All the unallocated bands are provisionally secured as new acquisition bands, and the destination node sends a connection setting notification including this acquisition band to the transmission source node if the provisionally acquired acquisition band is finally equal to the requested band. Returned to the adjacent node, if the provisionally obtained acquisition bandwidth is finally smaller than the required bandwidth, the maximum bandwidth that can be secured among the bandwidths that are equal to or less than this acquisition bandwidth and increased from the lowest bandwidth by the increment unit bandwidth is returned. An acquisition band is used, and a connection setting notification including the acquisition band is returned to the adjacent node on the transmission source node side. Therefore, when the unallocated bandwidth is smaller than the required bandwidth or the acquired bandwidth, the source node or the relay node temporarily reserves all the unallocated bandwidths as the acquired bandwidth, and is sequentially notified to the destination node by the connection setting request. The maximum bandwidth that can be secured among the bandwidths that are equal to or less than this acquisition bandwidth and increased by the increment unit bandwidth from the minimum bandwidth is collectively calculated as the acquisition bandwidth,
Each node is notified by the connection setting notification.

[0013]

Next, the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of a communication node according to an information communication method according to an embodiment of the present invention. In FIG.
1, a protocol processing unit 12, a bandwidth management table 13, and a line correspondence unit 14. Note that a communication node that performs only relay (hereinafter, referred to as a relay node) does not have the application processing unit 11.

Communication nodes (hereinafter, referred to as end nodes), which are parties to information communication, are connected to communication lines, respectively, and communicate with opposing end nodes via relay nodes. The protocol processing unit 12 performs processing of the protocol layer 3 or 4, such as connection setting release, communication band allocation, data transmission / reception, and routing. The bandwidth management table 13 is referred to by the protocol processing unit 12.
It is updated and holds information on the allocated bandwidth of the connection and the unallocated bandwidth that has not been used for each line.

The application processing unit 11 performs an application execution process, and the line corresponding unit 14 performs a process corresponding to layer 1 such as electrical matching with a communication line.
Note that the unit of the band is bit / sec, but the unit is omitted below and shown as a relative value for the sake of simplicity. Further, the protocol processing unit 12 sets the allocated band as an operation parameter of a conventionally known rate control, and performs transmission processing at a predetermined bit / sec speed.

Next, referring to FIGS. 2 and 3, a first embodiment of the present invention will be described.
As an operation according to the embodiment, a description will be given of a processing operation in the case where the attribute of the connection is one-way data transfer, or in both directions, but the bandwidth is secured only in one direction. FIG. 2 is an explanatory diagram showing an example of a packet header configuration.
(A) shows a basic configuration of a packet header, and (b) shows a header configuration for each packet type. As packet types related to connection setting, CR packets, CA packets, and RJ packets are provided.

The CR packet is a packet indicating a connection setting request transmitted from the transmission source node to the destination node. The CA packet is a packet indicating a connection setting response returned from the destination node to the transmission source node in response to the CR packet. The RJ packet is a packet returned from each node to the transmission source node and indicating a connection setting failure. The packet header of each packet is provided with a communication band display indicating details of the connection in addition to the destination node address, the source node address, and the connection identifier to be processed.

In particular, the display of the communication band of the CR packet includes:
A request band R, a minimum band M, an increment unit band D, and an acquisition band B are provided as information indicating a connection for which a setting request is made. The required bandwidth R is the required value desired by the application, the minimum bandwidth M is the minimum limit value for establishing the application, the incremental unit bandwidth D is a meaningful useful incremental value as viewed from the application, and the acquired bandwidth B is actually acquired. The resulting band is shown. Further, in the communication band display of the CA packet, an acquired band B confirmed at the destination node is provided. The communication band display of the RJ packet is not used.

FIG. 3 is a sequence diagram showing a communication flow in the case where the communication system comprises four nodes N1 to N4.
(A) shows a successful connection setting example, and (b) shows a failed connection setting example. In FIG. 3, an end node, that is, a source node N1 and a destination node N4 are connected via relay nodes N2 and N3. Below, xx
(R, M, D, B) represents the packet type xx and the communication band display (R, M, D, B).

A description will be given of a case where the requested band R from the upper application is notified from the transmission source node N1 to the relay nodes N2, N3 and the destination node N4 by displaying the communication band of the CR packet. However, it is not limited to this. Generally, when a connection is set, the required bandwidth R is determined using a predetermined area of the packet header.
In many cases, it is necessary to notify the relay node and the destination node from the source node. In such a case, the communication band indication provided in the packet header of the CR packet as in the present invention is used. It is not necessary to store the required bandwidth R in the area.

In the following description of the operation, the application processing unit 11 of the transmission source node N1 determines the required bandwidth R = 30, the minimum bandwidth M = 10, and the increment unit bandwidth D =
As an example, a case in which connection setting is requested as 5 will be described. First, with reference to FIG. 3A and FIGS. 4 to 7, a case where the connection setting is successful will be described. FIG.
Is a flowchart showing a connection setting process in the end node, FIG. 5 is a flowchart showing a packet receiving process in the end node, and FIGS. 6 and 7 are flowcharts showing a packet receiving process in the relay node.

Protocol processing unit 12 of source node N1
Responds to a connection setting request from a higher-level application executed by the application processing unit 11,
The connection setting process shown in FIG. 4 is started. First, a corresponding line is selected from the destination node address notified by the connection setting request from the higher-level application (step 101), and the unallocated band of the line is read from the band management table 13 (step 102). Requested bandwidth R notified by the allocated bandwidth and connection setting request
Are compared with each other (step 103). Here, since the unallocated bandwidth of the line to the next relay node N2 = 20,
It is determined that the required bandwidth R = 30 cannot be satisfied (step 10).
3: NO), the unallocated bandwidth is compared with the minimum bandwidth M notified by the connection setting request (step 10).
4).

In this case, since the minimum bandwidth M = 10, it is determined that a bandwidth equal to or greater than the minimum bandwidth M can be secured for the line to the relay node N2 (step 104: YE).
S) In steps 105 to 109, the maximum value that is less than or equal to the unallocated band and that can be temporarily reserved is obtained as the new acquisition band B by increasing the minimum band M by the increment unit band D at a time. B = M + D × n (n is an integer equal to or greater than 0) Note that the increment unit bandwidth D indicates a (significant) increase that is determined to be effective for the application when the secured bandwidth is increased. This value is specific to each application. Therefore, when increasing the band to be reserved, if only a band smaller than the increment unit band D can be reserved, the further band increase is stopped, so that useless band reservation can be avoided. , You can use the bandwidth effectively.

As a result, a new acquisition band B = 20 is obtained (steps 105 to 109), and a CR (30, 10, 5, 20, 20) packet is transmitted using this as the acquisition band B (step 110). Terminates the connection setting request process. In the connection setting request process,
For example, the remaining bandwidth when the new acquisition bandwidth B is allocated in Steps 106 and 109, that is, the new unallocated bandwidth is also obtained, and the bandwidth is provisionally secured by updating the bandwidth management table. In this case, the allocated bandwidth = 20 is registered as a new connection in the bandwidth management table, and the unallocated bandwidth = 0 is updated.

In step 103, if there is an unallocated band equal to or more than the requested band R notified by the connection setting request from the higher-level application (step 103: YES), the requested band R is set to the acquisition band B. At the same time (step 111), the band management table is updated to obtain a new unallocated band, and a band is temporarily secured (step 11).
2). Thereafter, a CR packet is transmitted to the next relay node (step 110), and a series of connection setting request processing ends.

If the unallocated band is smaller than the minimum band M in step 104 (step 104: N
O), it is determined that the bandwidth requested by the upper application cannot be secured, and the application is notified of the connection setting failure (step 113), and the series of connection setting request processing ends. In this way,
In the transmission source node N1, a predetermined bandwidth is provisionally reserved in response to a connection setting request from a higher-level application, and C indicating a bandwidth allocation request to the next relay node N2.
An R packet is transmitted. CR from source node N1
In response to the packet reception, the protocol processing unit 12 of the relay node N2 performs a CR packet reception process as shown in FIG.

First, the next line is selected from the destination node address of the received CR packet (step 151), the unallocated band of the line is read from the band management table 13, and the acquired band B is read from the CR packet (step 152). ). Here, the unallocated bandwidth of the line to the next relay node N3 = 17 is compared with the acquired bandwidth B = 20 (step 153), and since the unallocated bandwidth <the acquired bandwidth B (step 153: NO), Unallocated bandwidth = 17 and minimum bandwidth M
= 10 (step 154).

In this case, since unallocated bandwidth ≧ minimum bandwidth M (step 154: YES), it is determined that the acquired bandwidth B = 20 of the received packet header cannot be satisfied, and at steps 155 to 159, By increasing the increment bandwidth D by increments from the minimum bandwidth M, a maximum value that is less than or equal to the unallocated bandwidth and that can be temporarily secured is obtained as the newly acquired bandwidth B. B = M + D × n (n is an integer equal to or greater than 0) As a result, a new acquired band B = 15 is obtained (steps 105 to 109).
(0, 10, 5, 15) packets (step 1)
60), end the series of CR packet reception processing.

In the CR packet receiving process, for example, in steps 156 and 159, the remaining band when the new acquisition band B is allocated, that is, the new unallocated band is also obtained, and the band management table is updated. In this case, the allocated bandwidth = 15 is registered as a new connection in the bandwidth management table, and the unallocated bandwidth = 2 is updated.

Subsequently, in response to the reception of the CR packet from the relay node N2, the relay node N3 performs the CR reception packet processing of FIG. 6 as described above. First, in steps 151 to 153, the unallocated bandwidth of the line to the next destination node N4 and the acquired bandwidth R notified by the CR packet are read and compared. Here, since the unallocated bandwidth of the line to the destination node N4 is 30, it is determined that the acquired bandwidth B of the received CR packet can be satisfied (step 153: YES). As a result, the content of the communication bandwidth display in the packet header is not changed, the allocated bandwidth = 15 is registered as a new connection in the bandwidth management table, and the unallocated bandwidth =
15 (step 162) and a CR (3) having the same packet header as the received CR packet.
0, 10, 5, 15) and transmits the packet to the destination node N4.

The destination node N4 executes the CR packet receiving process shown in FIG. 5A in response to the reception of the CR packet from the relay node N3. First, the upper application is notified that there is a connection setting request based on the content of the received CR packet (step 121). Here, when the upper application can communicate, a CA (15) packet is created by setting the acquisition bandwidth B of the received CR packet to 15 as the acquisition bandwidth B of the CA packet that is the connection setting response packet. (Step 122), and transmit to the source node N1 node (Step 123).

As a result, in the relay node N3, as shown in FIG.
The CA packet receiving process shown in FIG. First,
At steps 171 to 173, the allocated bandwidth of the line to the next relay node N2 and the acquired bandwidth B notified by the CA packet
Are read and compared. Here, since the allocated band = 15 and the acquisition band B = 15 are equal, it is determined that there is no extra provisionally reserved band (step 173: NO), and the CA having the same acquisition band B as the received CA packet is determined. (1
5) Create a packet and transmit it to the source node N1 (step 175).

Similarly, the relay node N2 performs the CA packet receiving process shown in FIG. Also in this case, since the allocated band = 15 and the acquired band = 15 are equal (step 173: NO), a CA (15) packet having the same acquired band B as the received CA packet is created and transmitted to the source node N1. Send to (Step 1
75). If the allocated band is larger than the acquired band B notified by the CA packet (step 173: YE
S), calculating the new unallocated bandwidth by adding the difference between the allocated bandwidth and the acquired bandwidth B to the unallocated bandwidth, and updating the bandwidth management table by setting the acquired bandwidth B in the allocated bandwidth, thereby obtaining extra bandwidth. Release the band temporarily reserved (step 1
74), and transmits a CA packet having the acquisition band B (step 175).

In this way, the CA packet is transferred to the source node N1, where the CA packet receiving process shown in FIG. 5B is performed. First, step 131,
At 132, the assigned band of the connection and the acquired band B notified by the CA packet are read and compared. Here, since the allocated band = 20 is larger than the acquired band B = 15, it is determined that an extra provisional band is reserved as the allocated band (step 132: YES), and the difference between the allocated band and the acquired band B is determined as the unallocated band. In addition to the above, a new unallocated bandwidth is calculated and the bandwidth management table is updated to release an extra provisionally reserved bandwidth (step 133), and the acquired bandwidth B is notified to the upper application (step 134). ), C
The A packet reception process ends.

Thus, the application processing unit 11 of the transmission source node N1 recognizes that the connection of the acquisition band B = 15 has been set with the destination node N4, and starts a predetermined communication process. Becomes If the allocated bandwidth is equal to the acquired bandwidth B in step 132, it is determined that there is no extra provisionally reserved bandwidth (step 132: NO), and the bandwidth management table is not updated, and
The upper band application is notified of the acquisition band B (step 134), and the CA packet reception processing ends.

Next, referring to FIG. 3B, a case where the connection setting has failed will be described. Relay node N
Up to 2 is the same as when the connection setting was successful in FIG. In the relay node N3, the CR packet receiving process of FIG. 6 is performed. If the unallocated bandwidth of the line to the destination node N4 is 8, the unallocated bandwidth is smaller than the acquisition bandwidth B = 15 (step 153: NO) and the unallocated band is smaller than the minimum band M = 10,
It is determined that the bandwidth required for connection setting is insufficient (step 154: NO), and an RJ packet indicating connection setting failure is created and returned to the transmission source node N1 (step 163).

In response to this, the relay node N 2
The RJ packet receiving process shown in FIG. First,
At Steps 181 and 182, the allocated bandwidth = 15 of the connection is read from the bandwidth management table of the line to the relay node N3, and this is added to the unallocated bandwidth to calculate a new unallocated bandwidth = 17 to manage the bandwidth. By updating the table,
Release the unnecessary bandwidth and delete the information on the connection from the bandwidth management table (step 18).
3), create an RJ packet indicating the connection setting failure, and return it to the source node N1 (step 1)
84).

In response, the source node N1 performs the RJ packet receiving process shown in FIG. First, the assigned bandwidth = 20 of the connection is read from the bandwidth management table of the line to the relay node N2 (step 14).
1), this is added to the unallocated bandwidth and a new unallocated bandwidth =
20 and updates the bandwidth management table, thereby releasing the unnecessary bandwidth and deleting information on the connection from the bandwidth management table (step 14).
2), the connection setting failure is notified to the upper application (step 143). As a result, the application processing unit 11 of the transmission source node N1
4 is unsuccessful.

Next, referring to FIGS. 8 and 9, the second embodiment of the present invention will be described.
As an operation according to the embodiment, a description will be given of a processing operation in a case where the attribute of a connection is bidirectional data transfer and a band is secured in both directions. FIG. 8 is an explanatory diagram showing an example of the packet header configuration. As in FIG. 2B, the communication band display (request band R, minimum band M, increment unit band D, acquisition band B) is used as the packet header. Have. Further, for each connection in both directions, Sb is provided as a communication band display for the downlink connection, and Db is provided as a communication band display for the uplink connection. In the present invention, the down direction from the source node N1 to the destination node N4 in the same connection is referred to as a down connection, and conversely, the up direction from the destination node N4 to the source node N1 in the same connection. The direction is expressed as an upstream connection.

FIG. 9 is a sequence diagram showing a communication flow in the case where four nodes N1 to N4 are used.
(A) shows a successful connection setting example, and (b) shows a failed connection setting example. Note that the connection setting request processing and the packet receiving processing in each node are almost the same as those in FIGS. 5 to 8 described above, and thus detailed description using flowcharts is omitted. The main difference is that in each of the above-described FIGS.
Is performed only for the downlink connection from the destination node N4 to the destination node N4.
4, the same processing is performed for the upstream connection going to the transmission source node N1.

Note that xx (Sb: R, M, D, B) (D
b: R, M, D, B), packet type xx, communication band display from the source to the destination (Sb: R, M, D, B)
B), communication bandwidth display from the destination to the source (Db: R,
M, D, B). In the following description of the operation, the application processing unit 11 of the transmission source node N1 requests the same connection setting for the downlink connection as described above according to the application to be executed, and the requested bandwidth R initially requested for the uplink connection. = 50, minimum bandwidth M = 20, incremental unit bandwidth D = 5, and a case where a connection setting is requested will be described as an example.

First, the case where the connection setting is successful will be described. The protocol processing unit 12 of the transmission source node N1 starts the connection setting process shown in FIG. 4 in response to a connection setting request from a higher-level application executed by the application processing unit 11. First, a new acquisition bandwidth B = 20 is obtained in steps 101 to 109 similar to the above as a connection setting request for a downlink connection. In addition, the uplink is a transmission source node, and the connection does not exist.

Therefore, connection setting packets CR (Sb: 30, 10, 5, 2) for both connections
0) and (Db: 50, 20, 5,-) are created and transmitted to the relay node N2. It should be noted that the bandwidth management table 13 has an allocated bandwidth indicating a downlink connection as a new connection =
20 are registered, and the unallocated bandwidth in the bandwidth management table 13 is set to 0.

In response to the reception of the CR packet, the relay node N2 first performs the same processing as described above for the downlink connection based on the communication band indication Sb by the above-described CR packet reception processing of FIG. 15 (steps 151 to 159). Subsequently, processing is performed on the upstream connection based on the communication band display Db. Here, the line from the relay node N2 to the transmission source node N1 is targeted. In this case, the unallocated bandwidth = 3
0, and the required bandwidth R from the upper application is R = 5
Since it is 0, the acquisition bandwidth B = 30.

A description will be given of a case where the requested band R from the upper application is notified from the transmission source node N1 to the relay nodes N2, N3 and the destination node N4 by displaying the communication band of the CR packet. However, it is not limited to this. Generally, when a connection is set, the required bandwidth R is determined using a predetermined area of the packet header.
In many cases, it is necessary to notify the relay node and the destination node from the source node. In such a case, the communication band indication provided in the packet header of the CR packet as in the present invention is used. It is not necessary to store the required bandwidth R in the area.

In this way, the acquisition bandwidths B of both connections are obtained, and a new CR packet is created and transmitted to the relay node N3 (step 160). In this case, CR (Sb: 30, 10, 5, 15), (Db: 5
(0, 20, 5, 30) packets are created and transmitted, and a new connection is registered in the bandwidth management table 13 and an unallocated bandwidth is updated.

In the same manner, the relay node N3 obtains the acquisition bandwidth B for both connections. In this case, CR (Sb: 30, 10, 5, 15), (Db: 5
(0, 20, 5, 25) packets are created and transmitted, and a new connection is registered in the bandwidth management table 13 and an unallocated bandwidth is updated. Subsequently, the destination node N4
In the CR packet receiving process of FIG. 5A, the bandwidth allocation process as shown in FIG. 4 is performed only for the uplink connection based on the received CR packet, and the obtained bandwidth B = 20 is obtained here. .

As described above, in the destination node N4, the acquired bandwidth B =
15 and the acquisition bandwidth B of the upstream connection B = 20, and sets it in the connection setting response CA packet, and CA (Sb: 15), (Db:
20) is transmitted (steps 121 to 123). As a result, the relay nodes N3 and N2 compare the acquired bandwidth B of the received CA packet with the allocated bandwidth of each connection, release any extra provisionally reserved bandwidth, and release the bandwidth. And transmits the CA packet to the source node N1.

Therefore, in the relay node N3, the bandwidth temporarily reserved extra in the uplink connection = 25-20
= 5 is released, and in the relay node N2, an extra provisionally reserved band = 30-20 = 10 in the uplink connection is released. Further, the source node N1 performs the processing shown in FIG. 5B in response to the reception of the CA packet, compares the acquired bandwidth B of the received CA packet with the allocated bandwidth of the downlink connection, and extra Reserved bandwidth = 20−
15 = 5 is released, the bandwidth management table is updated, and the acquired bandwidth B is notified to the upper application (steps 131 to 134). Thereby, the application processing unit 11 of the transmission source node N1 recognizes that the downlink connection of the acquisition bandwidth B = 15 and the uplink connection of the acquisition bandwidth = 20 have been set up with the destination node N4.

Next, a case where the connection setting has failed will be described with reference to FIG. Relay node N
Up to 2 is the same as when the connection setting was successful. In the relay node N3, the CR packet reception process of FIG. 6 is performed for the downlink connection. If the unallocated bandwidth of the line to the destination node N4 is 8, the unallocated bandwidth is smaller than the acquisition bandwidth B = 15 ( Step 153:
NO), and since the unallocated bandwidth is smaller than the minimum bandwidth M = 10, it is determined that the bandwidth required for connection setup is insufficient (step 154: NO), and an RJ packet indicating connection setup failure is created. Then, it returns to the source node N1 (step 163).

In response, the relay node N2 performs the above-described RJ packet reception processing shown in FIG. 7B for both connections, thereby releasing the unnecessary bandwidths (step 181). 184). Further, the transmission source node N1 performs the above-described RJ packet reception processing shown in FIG. 5C on the downlink connection, releases the unnecessary bandwidth, and notifies the higher-level application of the connection setting failure (step S1). 141-143). Thereby, the source node N1
Recognizes that the connection setting request to the destination node N4 has failed.

As described above, at the transmission source node, based on the requested bandwidth R, the minimum bandwidth M, and the increment unit bandwidth D requested from the upper-level application, the required bandwidth from the unallocated bandwidth of the corresponding line to the required bandwidth R, or the unallocated bandwidth, A bandwidth that is equal to or less than the bandwidth and increased by the increment unit bandwidth D from the minimum bandwidth M is temporarily secured as an acquisition bandwidth B, and the minimum bandwidth M, the increment unit bandwidth D, and the acquisition bandwidth B are determined by the connection setting request packet CR in the destination node N4. Side, and at each relay node, based on the minimum bandwidth M, the increment unit bandwidth D, and the acquisition bandwidth B reported in the CR packet, from the unallocated bandwidth of the corresponding line to the acquisition bandwidth B, or the unallocated bandwidth. The following band, which is increased by the increment unit band D from the minimum band M, is temporarily reserved as the acquisition band B, and the minimum band M, the increment unit band D and the acquisition band B are acquired. The band B at connection setting request packet CR is obtained to notify to the destination node N4 side.

Further, the destination node returns a connection setting response CA packet including the obtained bandwidth B finally notified by the CR packet to the source node N1, and each relay node notifies the CA node of the connection setting response CA packet by the CA packet. Based on the acquired bandwidth B, the excess bandwidth is released from the allocated bandwidth temporarily secured by the CR packet, and the CA packet is transferred to the source node N1.
Based on the acquired bandwidth B notified in the packet, an extra bandwidth is released from the allocated bandwidth temporarily reserved in the CR packet, and the upper application is notified that the connection of the acquired bandwidth B has been set up to the destination node. It was made.

Therefore, as compared with a method of designating only a desired value or a method of designating a desired value and a minimum value as in the conventional connection setting request, the desired value or the desired value is determined according to the unallocated bandwidth of each line. Can flexibly secure the bandwidth amount closest to the ITU-T Recommendation H.264. 261 "px
For example, a communication method for performing moving image communication with a quality according to an available communication band, such as "64 kb / s video coding method for audiovisual communication", can be effectively used.

Further, as the increment unit area D, when the bandwidth to be reserved is increased, it is determined that the increase is significant (meaningful) for the host application, for example, the above-mentioned I
TU-T Recommendation H. 261 "px64 kb / s video coding method for audiovisual communication"
Since s is set, only the minimum required bandwidth can be temporarily reserved in each line without waste, the bandwidth available to other applications sharing the line increases, and network resources are effectively used. be able to.

When the unallocated bandwidth is smaller than the minimum bandwidth and the bandwidth cannot be secured in the relay nodes N2 and N3, the relay node N1 immediately returns an RJ packet notifying the connection setting failure to the source node N1. The source node and the relay node receiving the RJ packet immediately release the band temporarily reserved for the corresponding connection, so that if the connection setting fails, another application sharing the line can be used. The bandwidth is immediately increased, and network resources can be used effectively.

In addition to the downlink connection from the source node N1 to the destination node, as well as the uplink connection from the destination node to the source node N1, connection setting is simultaneously performed at each node based on a request from the upper application. Do,
If the bandwidth cannot be secured by either one of the connections, the provisionally secured bandwidth for both connections is immediately released, so that connection settings in both directions can be made collectively and If the setting fails, the bandwidth available to other applications sharing the uplink and downlink of the line increases immediately, and network resources can be used effectively.

In the above description, when the bandwidth is temporarily reserved at each node, if the unallocated bandwidth is smaller than the required bandwidth R or the acquired bandwidth B, the bandwidth is not more than the unallocated bandwidth and the minimum bandwidth M Has been described in which the bandwidth increased by the increment unit bandwidth D is temporarily reserved. However, the present invention is not limited to this. For example, a settable bandwidth is calculated by the destination node N4, and a CA packet is used. Source node N1
And the relay nodes N2 and N3.

That is, in the source node N1 and the relay nodes N2 and N3, if the unallocated bandwidth is sufficient, the required bandwidth R or the acquired bandwidth B is temporarily secured, and the unallocated bandwidth is the required bandwidth R or the acquired bandwidth. If the bandwidth is smaller than the bandwidth B, all the unallocated bandwidths are temporarily reserved as the acquisition bandwidth B, and are sequentially notified to the destination node side in a CR packet. Then, when the final acquired bandwidth B of the connection is equal to the required bandwidth R, the destination node N4 notifies this as an acquired bandwidth B to each node in a CA packet.

On the other hand, the final acquisition bandwidth B of the connection
Is less than the required bandwidth R, the acquired bandwidth B
Below, the maximum value when the increment bandwidth is incremented from the minimum bandwidth M by the increment unit bandwidth D is calculated as the acquisition bandwidth B, and this is notified to each node by a connection setting response CA packet. In response to receiving the CA packet, the source node N1
In addition, the relay nodes N2 and N3 release an extra band from the band temporarily reserved for the corresponding connection. Therefore, the calculation processing of the acquired bandwidth B performed when the unallocated bandwidth is smaller than the required bandwidth R or the acquired bandwidth B at each node is collectively processed at the destination node, and a higher-speed connection is performed. Settings can be realized.

[0061]

As described above, according to the present invention, at the transmission source node and the relay node, the requested bandwidth requested from the upper application or the acquired bandwidth notified from the adjacent node on the transmission source node side and the minimum bandwidth And the incremented unit bandwidth, based on the unallocated bandwidth of the line with the adjacent node on the destination node side, or the required bandwidth, or the bandwidth that is equal to or less than the unallocated bandwidth and increased by the increment unit bandwidth from the minimum bandwidth. Temporarily secure the maximum possible bandwidth as the acquisition bandwidth, and release the extra bandwidth from the initially temporarily reserved bandwidth based on the acquisition bandwidth notified by the connection setting response notification returned from the destination node. Then, the upper application is notified that the connection having the acquired bandwidth has been set between itself and the destination node. Therefore, as compared with a method of designating only a desired value or a method of designating a desired value and a minimum value as in the case of a conventional connection setting request, depending on the unallocated bandwidth of each line, the desired value or the value closest to the desired value is obtained. It is possible to flexibly secure a bandwidth amount, and the ITU-T Recommendation H.264 261 "p
It is possible to effectively use a communication system for performing moving image communication with a quality corresponding to an available communication band, such as “× 64 kb / s video coding system for audiovisual communication”.

Further, at the transmission source node, the relay node, and the destination node, the requested bandwidth individually requested for the downlink / uplink connection from the upper application or the acquisition bandwidth notified from the adjacent node on the transmission source node side;
Based on the minimum bandwidth and the incremental unit bandwidth, the required bandwidth from the unallocated bandwidth of the line to the adjacent node on the destination node side or the line between the adjacent node on the source node side, or less than the unallocated bandwidth The maximum bandwidth that can be secured is temporarily secured as the acquisition bandwidth among the bandwidths increased by the increment unit bandwidth from the minimum bandwidth, and the final acquisition bandwidth notified in the connection setting response notification returned from the destination node. Of the bandwidths initially provisionally secured for the respective connections, and release the excess / uplink connections having these acquired bandwidths with the destination node. This is to notify the application. Therefore,
As described above, it is possible to effectively use a communication method that performs moving image communication with quality according to the available communication band, and collectively set individual connections even when the bandwidth required for connections in both directions is different. And a higher-speed connection setting process can be realized.

Further, as the increment unit band, a band increase that is determined to be effective for a higher-order application when the band to be reserved is increased is set. For example, as the increase, for example, the aforementioned ITU-T Recommendation H. 26
1 In the “p × 64 kb / s video coding method for audiovisual communication”, by setting 64 kb / s, it is possible to temporarily secure only the minimum necessary bandwidth in each line without waste, and to share the line. The bandwidth available to other applications increases, and network resources can be used effectively. If the unallocated bandwidth is smaller than the minimum bandwidth when the bandwidth is temporarily reserved, the connection setting failure notification is sequentially transferred to each node on the source node side, so that each node temporarily reserves it. Since the reserved bandwidth is immediately released, if the connection setting fails, the bandwidth available to other applications sharing the line is immediately increased, and network resources can be used effectively. Also, when setting down / up connections collectively, if the connection setup fails in any of the connections, a connection setup failure notification is sequentially transferred to each node on the source node side. Since each node immediately releases the bandwidth temporarily reserved for both connections, if one of the connections fails to establish a connection, the other unnecessary connection is maintained. As a result, the bandwidth that can be used by other applications that share the uplink and downlink respectively increases immediately, and network resources can be used effectively.

When the unallocated bandwidth is smaller than the required bandwidth or the acquired bandwidth, the source node or the relay node temporarily reserves all the unallocated bandwidth as the acquired bandwidth, and sequentially notifies the destination node by a connection setting request. In the destination node, the maximum bandwidth that can be ensured among the bandwidths that are equal to or less than the obtained bandwidth and increased by the increment unit bandwidth from the lowest bandwidth is collectively calculated as the obtained bandwidth, and notified to each node by the connection setting notification. As a result, the calculation processing of the acquisition bandwidth B performed when the unallocated bandwidth is smaller than the required bandwidth R or the acquisition bandwidth B at each node is collectively processed at the destination node. High-speed connection setting can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a node according to an information communication method according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a configuration example of a packet header.

FIG. 3 is a sequence diagram showing a connection setting process.

FIG. 4 is a flowchart showing a connection setting request process in an end node.

FIG. 5 is a flowchart showing a packet reception process in an end node.

FIG. 6 is a flowchart illustrating a packet reception process in a relay node.

FIG. 7 is a flowchart showing another packet receiving process in the relay node.

FIG. 8 is an explanatory diagram showing another example of a packet header configuration.

FIG. 9 is a sequence diagram showing another connection setting process.

[Explanation of symbols]

N1 ... source node, N2, N3 ... relay node, N4 ...
Destination node, 11: application processing unit, 12: protocol processing unit, 13: bandwidth management table, 14: line correspondence unit.

Claims (6)

(57) [Claims] 1. An information communication system for setting a connection having a predetermined band in response to a request from a higher-level application in a communication network in which a transmission source node and a destination node are connected via one or more relay nodes and lines. In the method, the source node determines, based on a requested bandwidth, a minimum bandwidth, and an increment unit bandwidth requested from a higher-order application, an unallocated bandwidth of a circuit between the adjacent node on the destination node side and a required bandwidth or an unallocated bandwidth. The maximum bandwidth that can be secured among the bandwidths that are equal to or less than the bandwidth and increased by the increment unit bandwidth from the minimum bandwidth is provisionally secured as an acquisition bandwidth, and the minimum bandwidth, the increment unit bandwidth, and the acquisition bandwidth are notified to the destination node in the connection setting request notification. Relay node notifies the relay node of the minimum bandwidth notified in the connection setting request notification. Based on the incremental unit band and obtains band, acquired band component from remaining bandwidth of line between the destination node side of the adjacent node,
Alternatively, the maximum bandwidth that can be secured among the bandwidths that are equal to or less than the unallocated bandwidth and increased by the increment unit bandwidth from the minimum bandwidth is temporarily secured as the acquisition bandwidth, and the minimum bandwidth, the increment unit bandwidth, and the acquisition bandwidth are notified to the connection setting request notification. To the adjacent node on the destination node side, and the destination node returns a connection setting response notification including the acquired bandwidth finally notified in the connection setting request notification to the adjacent node on the source node side. Releasing an extra band among the bands temporarily reserved based on the acquired band notified by the connection setting response notification, and transferring the connection setting response notification to the adjacent node on the source node side, The source node uses the bandwidth temporarily reserved based on the acquired bandwidth notified by the connection setting response notification. An information communication method, which releases an extra band and notifies a higher-level application that a connection having a notified acquired band has been set with a destination node. 2. An information communication method for setting a connection having a predetermined band in response to a request from a higher-level application in a communication network in which a source node and a destination node are connected via a relay node and a communication line, The source node determines the required bandwidth, minimum bandwidth, and increment for each of the downlink connection from the source node to the destination node and the uplink connection from the destination node to the source node of the same connection, which are individually requested from the upper application. Of the bandwidth, based on the required bandwidth for the downlink connection, the minimum bandwidth and the increment unit bandwidth,
The maximum bandwidth that can be secured from the unallocated bandwidth of the line between the adjacent node on the destination node side and the required bandwidth, or the bandwidth that is less than or equal to the unallocated bandwidth and increased by the increment unit bandwidth from the lowest bandwidth as the acquisition bandwidth Temporarily secure, and notify the minimum bandwidth, increment unit bandwidth, and acquisition bandwidth of these two connections to the adjacent node on the destination node side with the connection setting request notification, and the relay node determines the downlink connection notified by the connection setting request notification. On the basis of the minimum bandwidth, the increment unit bandwidth, and the acquisition bandwidth, an increment of the acquisition bandwidth from the unallocated bandwidth of the line to the adjacent node on the destination node side or an increment of the increment bandwidth from the lowest bandwidth that is equal to or less than the unallocated bandwidth. While temporarily allocating the maximum bandwidth that can be secured as the acquisition bandwidth, the minimum bandwidth of the uplink connection, Based on the obtained bandwidth, it is possible to secure a bandwidth that is equal to or less than the obtained bandwidth from the unallocated bandwidth of the line between the adjacent node on the source node side and the bandwidth that is equal to or less than the unallocated bandwidth and increased by the increment unit bandwidth from the minimum bandwidth. The maximum bandwidth is temporarily reserved as the acquisition bandwidth, and the minimum bandwidth, increment unit bandwidth, and acquisition bandwidth of these two connections are notified to the adjacent node on the destination node side by the connection setting request notification, and the destination node sends the connection setting request notification. Based on the minimum bandwidth of the uplink connection, the increment unit bandwidth and the acquisition bandwidth notified as described above, from the unallocated bandwidth of the line to the adjacent node on the source node side to the acquisition bandwidth, or The maximum bandwidth that can be secured among the bandwidths increased by the increment unit bandwidth from the bandwidth is provisionally secured as the acquisition bandwidth, and the final acquisition of this uplink connection is performed. A connection setting response notification including the bandwidth and the acquired bandwidth of the downlink connection finally notified by the connection setting request notification is returned to the adjacent node on the source node side, and the relay node is notified by the connection setting response notification. Based on the acquisition bandwidth of each connection, the excess bandwidth is released from the bandwidth temporarily reserved, and this connection setting response notification is forwarded to the adjacent node on the source node side. Based on the acquired bandwidth of the downlink connection notified by the connection setting response notification, the excess bandwidth is released from the bandwidth of the downlink connection temporarily secured initially, and the acquired downlink and uplink acquisition bandwidths are notified. Notify the higher-level application that each connection has been set with the destination node. Information communication method, characterized by. 3. The information communication method according to claim 1, wherein a bandwidth increase determined to be effective for a higher-order application when a bandwidth to be secured is increased is set as the increment unit bandwidth. Information communication method. 4. The information communication method according to claim 1, wherein when the unallocated bandwidth is smaller than the minimum bandwidth, the relay node immediately returns a connection setting failure notification to the adjacent node on the source node side, Upon receiving the connection setting failure notification, the bandwidth temporarily reserved initially is immediately released, and the connection setting failure notification is immediately transferred to the adjacent node on the source node side. An information communication method characterized by immediately releasing a band temporarily reserved in response to receiving a failure notification, and notifying a higher-level application of a connection setting failure. 5. The information communication method according to claim 2, wherein the relay node and the destination node, when the unallocated bandwidth is smaller than the minimum bandwidth in one of the downlink and uplink connections, the adjacent node on the source node side. Immediately returns a connection setting failure notification to the server, immediately releases the bandwidth temporarily reserved for each of the downlink and uplink connections in response to the connection setting failure notification, and immediately releases the connection setting failure notification. Is immediately transferred to the adjacent node on the source node side, and the source node immediately releases the bandwidth initially reserved for each connection immediately upon receiving the connection setting failure notification, and An information communication method comprising: notifying a user of a setting failure of both connections. 6. The information communication method according to claim 1, wherein the transmission source node temporarily reserves a required bandwidth from the unallocated bandwidth, and transmits the requested bandwidth if the unallocated bandwidth is equal to or more than the required bandwidth. Is temporarily reserved as the acquired bandwidth, and if the unallocated bandwidth is smaller than the requested bandwidth, the entire unallocated bandwidth is temporarily reserved as the acquired bandwidth.If the relay node temporarily secures the acquired bandwidth from the unallocated bandwidth, If the allocated bandwidth is equal to or greater than the acquired bandwidth, the acquired bandwidth is temporarily reserved as a new acquired bandwidth, and if the unallocated bandwidth is smaller than the acquired bandwidth, all the unallocated bands are temporarily reserved as a new acquired bandwidth, If the finally acquired bandwidth is equal to the requested bandwidth, the destination node returns a connection setting notification including the acquired bandwidth to the adjacent node on the source node side, and finally the temporarily secured acquisition bandwidth is returned. If the acquired bandwidth is smaller than the required bandwidth, the maximum bandwidth that can be secured among the bandwidths that are equal to or less than the acquired bandwidth and increased by the increment unit bandwidth from the minimum bandwidth is set as the acquired bandwidth, and a connection setting notification including the acquired bandwidth is transmitted. An information communication method, wherein the information is returned to an adjacent node on the source node side.