JPH1117700A - Broadband network - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance degrees of freedom for a common share of a passive optical network(PON) on a subscriber side and to prevent the loss of data in an access node in the case of conducting on-demand service for each connection, using signaling in a broadband access network. SOLUTION: A service node 102 stores PON layer information of optical network units(ONU) 103-104 and band-connection information of a PON layer/ asynchronous transfer mode(ATM) layer of an access node 101 synchronously with the ONU and access node and the service node instructs an ONU assignment band revision of the PON layer. Furthermore, the service node 102 manages at the same time the ATM layer of the service node, the ATM layer of the access node and the PON layer, discriminates the connection and the service node supplies a cell stream, so that the ATM layer and the PON layer of the access node do not overflow.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to network control, and more particularly to dynamic connection control of a band including a PON.

[0002]

2. Description of the Related Art Conventionally, this type of PON (Passive Optical
Network) or PDS (Passive Double Star) bandwidth allocation control is performed by each ONU (Optical Network Uni
The control method is determined for the purpose of allocating t) to the optical layer by measuring the distance between the terminal points of the light and allocating the timing to be recognizable by the optical module.

For example, 5TH IEEE Conference on Optical
/ Hybrid Network Access `` Access Flexibility with Pa
ssive Double Star System '' Noriki MIKI and Kenji OK
For ADA (NTT), the downstream follows the upstream allocation and the upstream is T
Allocated on a DMA (Time Division Multiplex Access) basis, a destination specifying method using an ID and a timing position specifying method using a pointer are described.

[0004] Alternatively, in a CATV network which is one of the other shared media, a center side and a terminal side use an FPP (Framed Framed Network) as described in "NEC Technology December 1996, Internet Connection in CATV Network". Pipeli
Ne Polling) is known as a reservation method.
Japanese Patent Laid-Open Publication No. Hei 6-67961 discloses a similar method for allocating terminals to the ATM bus. When a vacant cell flows upstream of the bus, an assigned terminal ID is placed. The overwriting method is described.

[0005] Further, as one of the dynamic control methods in the basic model of the broadband access network, "Study on ATM Access System Configuration Applying Bearer Connection Control, IEICE December 1996 Issue" , Call control signal and B-BCC (Broadba
nd Bearer Connection Control) There is a description of a control method using a signal.Service-dependent functions such as subscriber data analysis are implemented in the service node, and only functions that do not depend on individual services such as the switch control function of the access node are provided. It is desirable that the access network function be provided, the access network transparently transfers the call connection message from the user to the service node, and the service node receiving the call connection message from the user performs processing such as subscriber data analysis, B-BCC for access network
It describes that transmission is performed using a channel, and that the access network performs setting / release of a VC by receiving a control signal from the service node.

[0006]

The control method according to the first prior art is intended to control an optical layer. As an initializing function of the apparatus, each of the ON / OFF states is controlled at both ends of the optical path.
Physical control of which timing is assigned to U is performed. Therefore, restrictions are imposed on dynamic bandwidth allocation for each connection in the broadband access network.

[0007] That is, in the PON networks currently being developed, although there are differences in the frame structure, paths and bands are statically set in each case, and the remaining ONUs allocate the surplus bandwidth to establish connections. ONUs that cannot be accepted and are statically assigned
The bandwidth has reached its peak and flexible network operation is not possible.

The control method of the second prior art requires a function related to an upper layer in order to secure the bandwidth and timing for the next packet every time a data packet is transmitted, and does not handle application services. Not applicable to broadband networks.

[0009] Further, the control method of the third prior art is as follows:
Since the direction of data flow and the direction of control match,
Upstream of access network using PON
Not applicable to control of m.

Further, since the control method of the fourth prior art is a method in which control is performed between an access node (AN) and a service node (SN) for each connection, a PON, a PDS or the like is shared on the subscriber side. No mention is made of the control when media is connected.
When shared media such as ON and PDS are connected, it is necessary to newly add a shared media control method.

[0011] An object of the present invention is to provide a function to easily and flexibly share a PON on the subscriber side when performing on-demand service for each connection using signaling in a broadband access network. It is to be realized at low cost as a network.

[0012]

In an access network using the control method of the present invention, the PON layer periodically and periodically synchronizes with a change in transmission timing assignment when the ONU is started up. Of the control frame exchanged at both ends of the access node is terminated at the access node, and at the same time, the information is sent to the service node.
When not only the layer connection information but also the ONU and PON information notified by the PON control frame are held and the information synchronized with the access node is shared, when the ONU bandwidth allocation is necessary, PO at service node based on information synchronized with node
N is assigned to ONUs, and changes are made via access nodes.

[0013] Specifically, the PON uplink control frame carries the band information of the path of each PON layer and transmits the PON layer from the ONU. When this is detected by the upstream PON layer control frame processing unit of the access node, the group management unit is referred to, and the VPI / VCI is determined based on the physical conditions such as the PON interface number and the contracted service class.
(Virtual Path Identifier: Virtual path identifier / Virtual
Channel Identifier (virtual channel identifier) is returned to the ATM layer with the logical condition indicated by the value. This flows to the service node, and in the service node, the PON layer control frame processing unit monitors the corresponding ATM path, obtains the real-time state information of the PON layer, and
Stored in the ON layer bandwidth management unit. At this time, the setting of the total bandwidth of the PON link capacity and the setting of the service class for each VP are notified to the service node in advance when the network is installed.

The terminal makes a request by signaling when there is a request for band change or the like. This is analyzed by the signaling protocol processing unit of the service node and notified to the connection / bandwidth management unit. The connection / bandwidth management unit determines whether it can be changed together with the information from the management unit of the PON layer. And when setting and changing,
Control and management of the ATM layer such as the switch unit of the access node are performed by the B-BCC protocol.
For the PON layer, a VC is allocated for downlink control, and is passed to and controlled by the PON layer control frame processing unit of the access node.

That is, in the present invention, the information regarding the PON layer allocation timing and the bandwidth for both the upstream and downstream is shared by the service node without terminating at the access node, and connection management and bandwidth management by signaling are performed on the service node side. At the same time, the PON layer is managed. However, at that time, the service node handles only the logical condition without grasping the physical condition of the access node. The physical condition of the access node is managed by the access node, and information after mapping from the physical condition to the logical condition is exchanged with the service node.

The access node has an upstream PON layer control frame processing unit as means for transmitting PON layer control information from the ONU to the service node, and as a means for confirming cooperation with the service node and the ONU, It has a downstream PON layer control frame processing unit for receiving confirmation and ONU bandwidth allocation change information and a group management unit, and has a bandwidth control unit and a connection control unit as means for coordinating the connection layer with the service node.

The service node grasps each ONU allocation position information, calculates the bandwidth of each ONU, and updates the total of the ONU allocation bandwidth per PON, the total connection bandwidth per PON, and the total connection bandwidth per ONU. And a PON layer bandwidth management unit as a means for calculating for each downlink and a means for holding information.

When a connection connection / release request is made by a user, the network side, the access node-service node, and the PON layer determine whether or not a connection can be accepted. Means to make a decision while referring to the table of
It has means for calculating and storing the total unused bandwidth amount for each.

Further, the service node has a function of adjusting the cell flow so that the ATM unit and the PON unit of the access node do not cause an overflow when transmitting the downstream cell. Specifically, when the connection is accepted, the switch control is set to the ATM section and the CDV (cell delay variation allowable value) is set so that the PON section does not overflow.

Each time a change in connection occurs, the timing assigned to each ONU in the access node is reported to the service node using a PON control frame. In the service node, the timing / bandwidth assigned to each ONU, the total bandwidth used by the PON,
The bandwidth actually allocated to the connection in the NU allocated bandwidth is managed. At the same time each ON from the service node
The U bandwidth change request is made to the access node using the PON control frame.

Thus, when there is a connection request and the available bandwidth in the ONU is insufficient but the connection can be accepted if the available bandwidth of another ONU is allocated.
By instructing the service node to change the bandwidth allocated to each ONU, the requested connection is accepted.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an access network function layout diagram showing an embodiment of the present invention, and FIG. 2 is a diagram showing connections set on the access network. The access network of the present invention includes an access node 101, a service node 102, a PON 10
5, consisting of ONU # 1 to ONU #n (103 to 104). Similarly, the backbone network extends to the service destination, and finally the terminal of the other end exists.

The access node 101 and each ONU 103-
Between the optical links 104, an optical link (P
ON connections # 1 to #n) 114 to 116 are connected. Connections 115 and 117 for users are established on the actual user and the access network. The upstream connection 115 includes an actual upstream data connection 137 and a signaling connection 135 terminated by the service node 102. Similarly, a connection 117 is established in the downlink, and a connection 138 for actual downlink data and a connection 136 for signaling terminated in the service node 102 are included.

At this time, if a connection setting request is made by signaling, it is possible to have a plurality of real data connections and to release the connections. In order to actually set and release the connection, it is necessary to set not only the service node 102 but also the access node 101. Therefore, a downlink B-BCC connection between the service node 102 and the access node 101 for the B-BCC protocol is required. 120 and up B-BC
A C connection 121 is provided.

In order to share the PON layer information with the PON layer terminating unit 106 of the access node 101,
An upstream PON layer control signal connection 119 and a downstream PON layer control signal connection 122 are provided.

The access node 101 performs the optical termination of the optical transmission in which the upstream and downstream wavelengths are multiplexed, and
A PON termination unit (OLT) 106 having an N layer frame extraction / assembly function, and a P controlling the PON termination unit 106
An ON control unit 140, an ATM switch unit 113,
ATM layer control unit 109 for managing the TM switch unit
And a B-BCC protocol processing unit 139 that terminates the B-BCC protocol and the ONUs 103 to 104, and includes a PON including transmission control information of a PON layer.
Uplink PO for analyzing and assembling the layer control frame, notifying the access node including the group management unit 112, and assembling the shared information to the service node, which is a feature of the present invention.
It has an N-layer control frame processing unit 107 and a downstream PON layer control frame processing unit 108, and a management table of a transmission position, a band, and a QOS (Quality of Service) for each ONU. Regarding ONU, its transmission position, band, QOS
Group management unit 11 having a management table for
2 is provided.

The ATM layer control section 109 has a B-BCC
The connection control unit 111 receives the information of the B-BCC protocol from the protocol processing unit 139, has a connection information table for each connection, and performs connection control in conjunction with the service node 102, and a bandwidth management table for each connection. It has a bandwidth control unit 110 that performs bandwidth management and monitors and controls input / output traffic.

The service node 102 has an ATM switch 125, a switch control unit 123 for controlling the ATM switch, a signaling protocol processing unit 126 for terminating signaling from a user, and a B-mode exchanged between the access node. B terminating BCC protocol
-A BCC protocol processing unit 127, a PON layer control frame processing unit 129 for analyzing a message of PON layer information, which is a feature of the present invention, and a PON layer bandwidth management for managing with six types of tables described later. Unit 128 has a bandwidth table for each connection, and performs connection and bandwidth management of the service node itself or CAC (Connection Admission Control), information based on B-BCC, and information of the PON layer bandwidth management unit 128. , A connection / bandwidth management unit 124 that manages the PON layer and performs CAC of the access node in the access node.

The PON layer bandwidth management unit 128
ONU number table for each ONU, upstream / downstream allocated bandwidth / timing table for each ONU, ONU allocated bandwidth total table for each PON, total table of bandwidth allocated to each ONU connection, bandwidth allocated to each PON connection It has a total table and a PON surplus bandwidth table that excludes the total bandwidth of the connections and the bandwidth required for control from the total bandwidth of the PON, and manages these six types of tables.

Next, the operation of the present invention will be described with reference to FIG. First, PON layer paths 114 to 116 are provided between the ONUs 103 to 104. In this process, the transmission position for each ONU is determined for each uplink and downlink by basically the same method as in the prior art, and the ONU is instructed.

That is, the PON control section 140 instructs the downstream PON layer control frame processing section 108 to transmit a PON layer control frame in cooperation with the group management section 112. PON layer control frame is PON
When sent to the ONU 103 via the
At 03, this is detected, and the PON control frame is returned to the PON termination unit (OLT) 106 as in the prior art.

Uplink PON layer control frame processing unit 10
7 processes the control frame sent from the ONU 103, determines which PON the ONU is on, and passes it to the group management unit 112. In the PON control unit 140,
The upstream transmission timing to be assigned to the ONU is determined together with the information about the other ONUs written on the group management unit 112 and stored in the group management unit 112.

[0033] This stored information is placed on the downstream PON control frame via the downstream PON layer control frame processing unit,
The ONU 103 is notified. At this time, how much bandwidth is allocated to the PON connection 114 is determined in advance as an initial value and stored in the group management unit 112. However, this value does not need to be fixed and is determined by service conditions, operating conditions, and the like. The storage method in the group management unit 112 can be appropriately set in terms of hardware or software. On the downstream side, there is no bandwidth management means as a PON layer as in the conventional technology, and the bandwidth control unit 110 establishes a connection 11 between each user.
7 are controlled.

The PO held by the group management unit 112
The N information is periodically notified to the PON layer control frame processing unit 129. This is performed by notifying the information held in the group management unit 112 by overwriting via the PON layer control signal connection 119 after the upstream PON layer control frame processing unit 107 terminates the control frame.

The PON layer control frame processing section 129 notifies the downstream PON layer control frame processing section 108 via the PON layer control signal connection 122 that the notification has been received. The downstream PON layer control frame processing unit 108 processes this frame and notifies the group management unit 112 of the information. As a result, when a mismatch occurs between the access node 101 and the service node 102, the mismatch is detected by the group management unit 112. In that case, the group management unit 112
The information is passed again to the PON layer control frame processing unit 129 via the N layer control frame processing unit 107 and the PON layer control signal connection 119, and the contents of the PON layer band management unit 128 are made to match the contents of the group management unit 112.

The PON layer bandwidth management unit 128 calculates and retains the allocated bandwidth for each ONU from the uplink transmission timing notified via the PON layer control signal connection 119, similarly to the table of the group management unit 112.
In addition, the total bandwidth of ONUs connected to the PON is calculated and held.

Since the control information on the downlink is not held in the access node 101 side, the service node 1
02 is controlled so as not to exceed the total bandwidth of the PON. Therefore, the PON layer bandwidth management unit 128 holds information on the downlink bandwidth allocated to the access node 101 and the ONUs 103 to 104.

In the ATM layer, the ATM layer control unit 1
09 has the same information as the connection bandwidth management unit 124.
However, when a new connection is set, the connection band management unit 124 is updated, and at the same time, the B-BCC protocol processing unit 139 on the access node 101 side via the control signal 133 and the B-BCC protocol processing unit 127. The B-BCC protocol is exchanged between.

The B-BCC protocol processing unit 139 analyzes the contents of the instruction from the connection band management unit 124 and updates information on the band control unit 110 and the connection control unit.
The ATM layer control unit 109 changes the control of the ATM switch 113 according to this.

Next, a case where a user terminal connected to the end of the ONU issues a connection request will be described. First, the user establishes connection 135 for user signaling.
When a connection request is issued by signaling using, the signaling protocol processing unit 126 terminates the signaling and starts processing by detecting it.

In the connection band management unit 124, the PO
Reference is made to the ONU of the user who has made the connection request from the N-layer bandwidth management unit 128 and the bandwidth allocated for uplink and downlink.
In addition, the connection band management unit 124 stores the requested connection band in the PON layer band management unit 128.
Then, the bandwidth added to the sum of the bandwidths of the connections currently being set in the ONU and stored therein is calculated. Further, a comparison process is performed between the calculated value and the assigned bandwidth value of the upstream or downstream of the ONU obtained by referring to the PON layer bandwidth management unit 128.

As Case 1, if the total bandwidth given to the user terminal does not exceed the bandwidth allocated to the ONU at that time, the connection bandwidth management unit 124
It is determined that the bandwidth does not exceed the bandwidth allocated to the NU (or the connection bandwidth management unit 124
Section Admission Control) If it is determined that the connection can be accepted without changing the allocated bandwidth of the ONU according to the algorithm, the management table of the connection bandwidth management unit 124 is updated, and the B-BCC protocol processing unit 127 is updated. And 139
The setting of the ATM layer control unit 109 is changed via the server and a new connection is established.

At the same time, the connection bandwidth management unit 124
Calculates the total sum of the connection bandwidths accommodated for each ONU and the total sum of the connection bandwidths accommodated for each PON, and updates those values stored in the PON layer bandwidth management unit 128.

As Case 2, the bandwidth of the requested connection exceeds the bandwidth allocated to the ONU accommodated at that time, and the bandwidth to the connection established in another ONU of the PON. If the sum of the remaining bandwidths other than the minutes does not reach the required value, the connection bandwidth management unit 124 adds the requested new connection bandwidth to the ONU stored in the PON layer bandwidth management unit 128. Exceed the allocated bandwidth value,
And the PON layer band management unit 128 detects that the sum of the remaining bands for each PON is equal to or less than the requested band.

In this case, the connection bandwidth management unit 1
24 notifies the signaling protocol processing unit 126 of the fact with an immediate control signal 132, and the signaling protocol processing unit 126 performs connection rejection protocol processing.

In case 3, the bandwidth of the requested connection exceeds the bandwidth allocated to the ONU accommodated at that time, and the bandwidth of the connection to another ONU of the PON is extended. If it is smaller than the sum of the remaining bandwidths excluding the connection bandwidth, the connection bandwidth management unit 12
4 detects that the bandwidth exceeds the bandwidth value assigned to the ONU stored in the PON layer bandwidth management unit 128 by adding the requested new connection bandwidth, and that the requested bandwidth is It is detected that it is equal to or less than the sum of the remaining bands for each PON in the layer band management unit 128.

In this case, the bandwidth allocated to each ONU is reallocated, and then the requested connection is accepted. That is, at the time of the re-allocation processing of the bandwidth allocated to each ONU, the PON layer bandwidth management unit 128 keeps the previous table as it is and temporarily holds the table information after the re-allocation. At the same time, the temporary holding information is transmitted to the PON layer control frame processing unit 129.
PON layer control frame processing unit 108 via
Notify.

Downlink PON layer control frame processing unit 10
8 detects this temporarily stored information, temporarily saves it in the group management unit 112, and
To the ONUs 103 to 104 via. At this time, control frames are transmitted in order from the ONU to be reduced. Each ONU makes a change using a control frame, and simultaneously sends a control frame to the upstream PON layer control frame processing unit 107.

Uplink PON layer control frame processing unit 10
In 7, the control frame is turned on by monitoring the control frame.
U recognizes that the band has been changed. Thereby,
The information temporarily saved by the group management unit 112 is formally rewritten.

Also, in order to synchronize with the information of the PON layer bandwidth management unit 128, the upstream PON layer control frame processing unit 107 to the PON layer control frame processing unit 129
Is notified. When the PON layer control frame processing unit 129 recognizes that the ONU has changed the band, the information temporarily stored in the PON layer band management unit 128 is rewritten as formal information.

Thereafter, the connection band management unit 124
Performs the reception control of the requested connection again. That is, the management table of the connection band management unit 124 is updated, the setting of the ATM layer control unit 109 is changed via the B-BCC protocol processing units 127 and 139, and a new connection is established.

At the same time, the connection bandwidth management unit 124
Calculates the total sum of the connection bandwidths accommodated for each ONU and the total sum of the connection bandwidths accommodated for each PON, and updates those values stored in the PON layer bandwidth management unit 128.

FIG. 4 clarifies, in the access network function layout diagram of FIG. 1, a part in which functions are added or expanded in the present invention, and dotted lines indicate functions newly added in the present invention. , And the hatched portion indicates a portion whose function is expanded in the present invention.

FIG. 3 is an access network function layout diagram showing another embodiment of the present invention. In this embodiment, in order to synchronize the PON layer control frame processing unit 129 and the access node 101 side, all B-BC
This embodiment differs from the embodiment of FIG. 1 in that communication is performed using the C protocol processing units 127 and 139, but the basic operation is the same as that of the embodiment of FIG.

[0055]

According to the present invention, in a service node, O
The PON layer information of the NU and the band / connection information of the PON layer / ATM layer of the access node are turned ON.
U, which is held in synchronization with the access node and configured so that the ONU allocation bandwidth of the PON layer can be changed from the service node. Therefore, when there is a connection request and the remaining bandwidth of the ONU is insufficient, The connection request can be accepted by allocating the remaining bandwidth of the ONU.

Further, according to the present invention, the service node manages the ATM layer of the access node, the ATM layer of the access node, and the PON layer at the same time to determine whether the connection is accepted, and then the service node determines the ATM layer, the PON layer of the access node. Is rectified and flowed so that overflow does not occur.
No overflow occurs in the M section and the PON section.

[0057]

[Brief description of the drawings]

FIG. 1 is an access network function layout diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing connections set on the access network of FIG.

FIG. 3 is an access network function layout diagram showing another embodiment of the present invention.

FIG. 4 is a diagram for explaining a function added by the present invention to an access network in a conventional PON.

[Explanation of symbols]

Reference Signs List 101 access node (AN) 102 service node (SN) 103 ONU (Optical Network Unit) # 1 104 ONU (Optical Network Unit) #n 105 PON (Passive Optical Network) 106 PON terminal unit (OLT) 107 upstream PON layer control frame Processing unit 108 Downlink PON layer control frame processing unit 109 ATM layer control unit 110 Bandwidth control unit 111 Connection control unit 112 Group management unit 113 ATM switch 114 PON connection # 1 115 Uplink VC (Virtual Channel) 116 PON connection #n 117 Downstream VC (Virtual Channel) 118 Control signal in AN 119 PON layer control signal (AN → SN) 120 B-BCC (Broadband Bearer Connection C)
ontrol) protocol (SN → AN) 121 B-BCC (Broadband Bearer Connection C)
ontrol) protocol (AN → SN) 122 PON layer control signal (SN → AN) 123 Switch control unit 124 Connection / bandwidth management unit 125 ATM switch 126 Signaling protocol processing unit 127,139 B-BCC protocol processing unit 128 PON layer bandwidth management Unit 129 PON layer control frame processing unit 130, 131, 132, 133, 134 SN control signal 135 uplink signaling protocol 136 downlink signaling protocol 137 uplink user connection 138 downlink user connection 140 PON control unit

Claims (10)

[Claims] 1. A broadband network in which a subscriber is connected via a PON and has a device or function for dynamically performing connection control, comprising a PON function block and a connection control function block, wherein the PON function block is connected to the connection control function block. To the ONU on the PON, the transmission position assigned to each ONU and the information on the band are notified and confirmed.
A broadband network, comprising: sharing information synchronized with an ON function block to control a PON layer from the connection control function block to the PON function block. 2. The information regarding a transmission position and a band assigned to each of the ONUs on the PON,
2. The broadband network according to claim 1, wherein the PON function block notifies and confirms the connection function block using the control frame position. 3. The apparatus or function for dynamically performing connection control is arranged in a service node, the PON function block is arranged in an access node, and the service node performs monitoring with the information of the PON, 2. The broadband network according to claim 1, wherein the access node is instructed to change the ONU assignment position on the PON. 4. The access node has an ATM function, and the service node includes the ATM on the PON.
4. The broadband network according to claim 3, wherein the ATM switch is controlled simultaneously with the NU band. 5. The apparatus or function for dynamically performing connection control is arranged in a service node, the PON function block is arranged in an access node, and the service node has information of the PON, and a connection request from a user is provided. Sometimes, connection acceptance control including the PON is performed, and the service node transmits the ONU on the PON to the access node.
2. The broadband network according to claim 1, wherein an instruction to change an assignment position is issued. 6. The access node has an ATM function, and when a connection request is made from a user, the service node controls connection acceptance of the PON and ATM at the same time, and the service node sends an ATM to the access node. 6. The broadband network according to claim 5, wherein control of a switch and an instruction to change the ONU assignment position on the PON are issued. 7. The service node, wherein the PO
N, and periodically notifies information on the transmission position and the bandwidth assigned to each ONU on N, and at the same time, responds to the confirmation request from the service node, and issues an instruction to change the bandwidth / transmission position of each ONU from the service node. Receiving P
7. The broadband network according to claim 3, further comprising an access node for performing ON control. 8. A total sum of bands allocated to each of the ONUs on the PON while holding information on transmission positions and bands allocated to each ONU on the PON from the access node. Calculate and hold, and calculate and hold and manage the transmission allocation position for each ONU, the allocated bandwidth for each ONU, and the surplus bandwidth for each ONU, and change the allocation to each ONU based on the judgment made by the bandwidth management unit. 5. The broadband network according to claim 3, further comprising a service node that instructs the access node to change one or both of settings of the ATM unit and the ATM unit. 9. A sum total of bands allocated to the ONUs for each PON and an unused band for each of the ONUs, holding information on a transmission position and a band allocated to each ONU on the PON from the access node. Is calculated and held, and the transmission allocation position for each ONU and the allocated bandwidth for each ONU are calculated and stored, and each time there is a connection request from a user, the total bandwidth allocated to the connection for each connection ONU. , Recalculates and retains the surplus bandwidth for each ONU, performs connection acceptance processing based on judgment by the connection / bandwidth management unit, notifies the user,
7. The broadband network according to claim 5, further comprising a service node for instructing the access node to change one or both of assignment of each ONU and setting of an ATM unit. 10. The service node according to claim 1, wherein the bandwidth of the requested connection accommodates the ON state currently accommodated.
If the bandwidth exceeds the bandwidth allocated to the U and is smaller than the sum of the remaining bandwidth excluding the bandwidth to the connection established in another ONU of the PON,
4. The broadband network according to claim 3, wherein the bandwidth allocated to the NU is reallocated, and thereafter, the access node is instructed to accept the requested connection.