JP3519601B2 - Group communication device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention
Computer that transmits packets between computer devices
Computer communication that belongs to a predetermined group.
Group communication that can only communicate between
Is what you do. Here, the address is a MAC (Media
Access Control (medium access control)
Say. 2. Description of the Related Art Computers for home users have hitherto been used.
A dial-up communication line is used as a data communication system.
Use to packetize data between computer devices
Cable monitoring using a transmission system or CATV line
Wide range of communication methods between computer devices using dem
Have been built. [0003] In the former case, the Ethernet at a remote location
To connect the nets, bridges or routers at both ends
Set up Ethernet packets (IP
Protocol) on the communication line for communication.
Is common. That is, Ethernet packet
Or IP packet is transferred to HDLC (High Level Data Link).
Control) and PPP (Point-to-Point Protocol)
It is transmitted using a protocol. The HDLC protocol has a start flag and an end flag.
Map packets between lags and transmit on communication line
I do. On the other hand, in the latter case, the cable installed in the house
Modem is connected to the user by Ethernet connection interface
And connect to the center LAN. [0005] The above-mentioned cable modem system enables the market
Using a sales LAN switch, etc.,
Providing group communication service that enables communication only between terminals
Can be offered. A conventional example will be described with reference to FIG.
I will tell. FIG. 13 is an overall configuration of a conventional group communication device.
FIG. In FIG. 13, reference numeral 1-1 denotes a cable for subscriber premises.
Cable modem, code 1-2 is a subscriber system (CATV
Subscriber line such as a line), reference numeral 1-3 is a relay amplifier, and reference numeral 1
-4 is an Ethernet interface, 1-5 is a cable
Head end unit for controlling a bull modem,
6 is a cable modem on the center side, and 1-7 is a center L
AN, reference numeral 1-8 denotes a terminal, reference numeral 1-9 denotes a LAN switch.
Reference numeral 3 denotes a center processing device. Here, terminal 1-
8 is a computer device. The operation will be described below. [0006] Cable modems are available for cable TV.
Channel to realize high-speed digital transmission.
Yes, going up (going from user side to center side) / going down
(From the center side to the user side)
Nominal type and asymmetric type where the down speed is faster than the up speed.
You. Ethernet on the user side in cable modem 1-1
Provide interface 1-4 to connect terminal 1-8
You. Digitally modulates the signal from terminal 1-8,
Center processing via system (coaxial cable) 1-2
The data is transmitted to the device 3. In the center processing unit 3, the cable model
It is connected to the center LAN 1-7 via the system 1-6. Model
Communication control of the head-end (including translator etc.)
(M) The section 1-5 performs the operation, and the user shares the communication channel.
You. Therefore, when it is idle, make full use of the transmission speed.
However, if another user interrupts, the speed will decrease. A LAN switch 1 is connected to the center LAN 1-7.
-9 is connected. In a general cable modem system
A router is connected instead of the LAN switch 1-9
But realize group communication between limited members
Therefore, a LAN switch 1-9 is required. Sandals
That is, the center side has a VLAN (Virtual LAN) function.
Grouping is performed by installing switches. [0008] Group communication with the LAN switch 1-9
Or as a method to form a VLAN, (1)
Per port, (2) per IP subnet, and (3) M
There are three types of AC address units. [0009] In the above method,
(1) In the port setting, if the number of groups increases,
(2) IP layer VLAN
Is because users can easily change the IP address settings
Difficult to ensure security, (3) MAC
In the ear VLAN, it is necessary to set the terminal address individually.
And the number of terminals increases the management effort.
That the broadcast packets connect to the port
Processing load on the terminal is large because it reaches all terminals
There is a problem. The present invention has been made in such a background.
Connected to the registered member edge device
Terminals in group communication that communicate only between terminals
Security by filtering using the address of
To provide a group communication device that can improve
The purpose is to: The present invention provides a method for registering terminal address information.
Improved user convenience by automating the recording process
To provide a group communication device that can
Target. The present invention relates to the arrival of broadcast packets.
Improve security and reduce terminal processing load by limiting the range
To provide a group communication device capable of achieving reduction
aimed to. The present invention provides an address search process and an address search process.
Group communication that can reduce dress processing time
It is intended to provide a device. The present invention provides a group communication device.
The present invention is characterized in that a large number of terminals
And a center processing unit that accommodates this terminal via a communication line.
And one or more of the terminals are inserted into the communication line.
And a plurality of edge devices.
Edge devices assigned to the loop and belonging to the same group
Allow packets to be sent and received between terminals connected to
It is provided with group communication means. [0012] The edge device and the center processing device
File containing packets transmitted and received between the terminals.
Means for composing a frame, wherein said group communication means
Between the edge devices belonging to the same group.
May include group communication means to allow
desirable. Further, the group communication means includes the edge.
Connected to the group to which the edge device belongs and the edge device
Including a table in which addresses of the terminals are recorded
Is desirable. [0013] As described above, the group communication means includes a group.
To manage loop communication using edge devices,
Using terminal address in loop communication
Security can be improved. For example, other
Access to devices belonging to the group in violation of the rules.
If there is a terminal trying to access,
Violating terminal sends a packet by falsifying its own address
The edge device to which the terminal is connected.
The legitimacy was determined by examining the
Packets transmitted by terminals that violate the rules
Can be effective. Further, when checking addresses, the same
Only the terminal addresses under the edge device belonging to the group are
Just search for the address, so the address search process and
Address search time can be reduced. The edge device is connected to itself.
Notify the group communication means of the address information of the
It is desirable to include such means. As described above, the registration processing of the terminal address information is performed.
The user experience by automating the process
be able to. At this time, the notifying means is provided at a predetermined cycle.
Check the address information of the terminal every time
It may be configured to include means for notifying the means, or
Means for notifying, the terminal connected to the self
When the configuration changes, check the address information of the terminal.
A configuration including means for notifying the group communication means;
May be. The group communication means transmits the frame
All the terminals to which the included packet belongs to the same group
Determine whether the packet is a broadcast packet addressed to the
And the determination result of this determination
When indicating a broadcast packet, the broadcast
A group identifier to the frame containing the packet
Means for transmitting to each of the edge devices
Is desirable. In this manner, each edge device has a broad key.
The frame that has been cast is
Group identifier is referenced, and the group identifier
Accept the frame if it indicates a group to do
The frame if it indicates another group.
Broadcast to a given group by discarding
Packet can be distributed. Alternatively, the group communication means includes:
The packets included in the frame belong to the same group
Broadcast packets addressed to all terminals
Means for judging whether or not, and the judgment result of this judging means
Indicates a broadcast packet,
The frame containing the broadcast packet to the same
Transmit to each of the edge devices belonging to the loop
It is also possible to adopt a configuration including means. As described above, from the beginning, it belongs to a predetermined group.
Broadcast only to the edge device that
Invalid frames discarded by distributing frames
The bandwidth can be used effectively without performing the transfer. Further, the edge device and the center processing
Includes control information transmission / reception packets transmitted / received to / from the device
Means for configuring a control frame is provided;
Communication between edge devices belonging to the same group
Group communication means permitting transmission and reception of control frames
Is desirable. Thus, there is no need to transfer to the terminal.
The information transmission packet is transmitted between the edge device and the center processing device.
Can be transferred using group communication. I
Therefore, unnecessary transmission of control information to the terminal
Security is improved, and unnecessary
No need to process necessary control information transmission packets
The load can be reduced. At this time, the group communication means includes:
The control information transmission packet included in the control frame
Is a block addressed to all edge devices belonging to the same group.
Means for determining whether the packet is a broadcast packet,
If the determination result of this determination means is a broadcast packet,
When indicating a broadcast packet, the broadcast packet is included.
A group identifier is added to the control frame
Means for transmitting data to the edge device.
Or the group communication means comprises:
The control information transmission packet included in the control frame
Is a block addressed to all edge devices belonging to the same group.
Means for determining whether the packet is a broadcast packet,
If the determination result of this determination means is a broadcast packet,
When indicating a broadcast packet, the broadcast packet is included.
The control frame belonging to the same group.
A configuration including means for transmitting data to the edge device is provided.
Can be DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 to FIG.
This will be described with reference to FIG. FIG. 1 shows a group according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating an overall configuration of a communication device. FIG. 2 shows the implementation of the present invention.
FIG. 3 is a block diagram of a main part of an example edge device. Figure 3 is a book
FIG. 3 is a block diagram illustrating a main part of a node unit according to an embodiment of the invention; Figure
FIG. 4 is a configuration diagram of a table according to the embodiment of the present invention. The present invention relates to a group communication apparatus,
The feature of light is that, as shown in FIG.
Terminal 1-8 and a subscriber system including a communication line.
A center processing device 3 housed through the stem 1-2;
End 1-8, one or more of
Edge device 2-1.
Devices assigned to the group and belonging to the same group
Transmission and reception of packets between terminals 1-8 connected to -1
2-2 as a group communication means that allows
And a node section 2-3. In the edge device 2-1 and the node unit 2-3,
Are, as shown in FIGS. 2 and 3, the edge device 2-1 and
Transmission / reception to / from terminal 1-8 transmitted / received to / from center processing device 3
As a means to compose a frame containing the packets
Processors 6-1 and 7-1 are provided.
The unit 2-3 includes an edge device 2-1 phase belonging to the same group.
The transmission and reception of the frame are allowed between each other. In the node section 2-3, as shown in FIG.
Edge created according to information from management unit 2-2
The group to which the device 2-1 belongs and the edge device 2-1
A table in which the addresses of the connected terminals 1-8 are recorded.
Including The processor 6 of the edge device 2-1
1 manages the address information of the terminal 1-8 connected to itself.
To the management unit 2-2. At this time, the processor 6-1
Checks the address information of the terminal 1-8 at predetermined intervals, and
May be notified to the management unit 2-2, or
The processor 6-1 has a configuration of the terminal 1-8 connected thereto.
When the configuration changes, the address information of the terminal 1-8 is confirmed.
The notification may be notified to the recognition management unit 2-2. In the first embodiment of the present invention, the node unit 2
-3 of the processor 7-1, before being included in the frame,
The packet is sent to all terminals 1-8 belonging to the same group.
Determine if the packet is a broadcast packet addressed to it
If the result of the determination indicates a broadcast packet,
The frame containing the broadcast packet.
All the edge devices 2-
1 to each of them. In the second embodiment of the present invention, the
The processor 7-1 is configured to transmit the packet included in the frame.
Packet addressed to all terminals 1-8 belonging to the same group
It is determined whether the packet is a broadcast packet.
When the determination result indicates a broadcast packet,
The frame containing the broadcast packet is
To the edge devices 2-1 belonging to the same group.
And send. The edge device 2-1 and the center processing device
3 including a control information transmission / reception packet
Processor 6-1 as Means for Constructing Customer Frame
And 7-1, and processors 6-1 and 7-1
Is a value between the edge devices 2-1 belonging to the same group.
The transmission and reception of the control frame are permitted. In the first embodiment of the present invention, the
The processor 7-1 performs the processing before the control frame is included in the control frame.
All the control information transmission packets belong to the same group
Broadcast packet addressed to the edge device 2-1
Is determined, and the result of this determination is broadcast
When the broadcast packet is indicated,
A group identifier to the control frame including the packet
Then, the data is transmitted to all the edge devices 2-1. In the second embodiment of the present invention, the
The processor 7-1 performs the processing before the control frame is included in the control frame.
All the control information transmission packets belong to the same group
Broadcast packet addressed to the edge device 2-1
Is determined, and the result of this determination is broadcast
When the broadcast packet is indicated,
The control frame including the packet belongs to the same group.
To the corresponding edge device 2-1. An embodiment of the present invention will be described. The above description
The frame is referred to as the encapsulated Ethernet in the following description.
Corresponds to a net packet. In the embodiment of the present invention shown in FIG.
The group communication device is a conventional group communication device shown in FIG.
Compared with the communication device, the edge device denoted by reference numeral 2-1 and the reference numeral 2-
2 are different from each other in a node unit and a management unit 2-3. these
The device is the cable modem 1 described in the conventional example shown in FIG.
-1 and connected to one LAN.
And are communicable with each other. The outline of the operation will be described below. Edge device 2
-1 is connected by Ethernet interface 1-4
The address information of the subordinate terminal 1-8 is detected, and the management unit 2-
Notify 2. The communication protocol at this time is SN
MP protocol is available. In the management unit 2-2,
Based on the group registration information from the user in advance, the edge
Link the device 2-1 and the subordinate terminals 1-8 to the group information.
And send the information to the node device 2-3 as an SNMP protocol.
Notify by col. The group registration information is for group identification.
The ID is notified to the node unit 2-3 and the edge device 2-1.
Keep it. The notification of the address information of the terminal 1-8 causes the
When a user adds or changes a terminal 1-8,
It is no longer necessary to apply for contact information to the network side.
Furthermore, when the terminal 1-8 moves between users, the destination
Is notified as a new terminal from the edge device 2-1 of
Therefore, by the address duplication check in the management unit 2-2,
You can confirm that the terminal is moving, and update the information to move the terminal.
It becomes possible to support. In the node section 2-3,
Packets from the terminal 1-8 connected to the edge device 2-1
Packet filtering based on the destination address of the
Do. Next, packet transmission method and filtering
The operation will be described. In the edge device 2-1, the terminal 1-
8 as a packet
As a packet transmitted from the edge device 2-1.
The packet is transmitted to the node unit 2-3.
Restore packets from -8, packets are unicast
Packet, and the transmission / reception address of the packet
As a result of collation with the group information notified earlier from -3,
If the packet is registered in the same group,
From the node unit 2-3.
The packet to which the destination terminal 1-8 is connected is
To the device 2-1. The packet is broadcast
If it is a packet, it is encapsulated by adding group identification information
Of the broadcast transmitted from the node unit 2-3.
Send as Ethernet packet. Where the capsule
Is the edge of the Ethernet packet from terminal 1-8
The data area of the Ethernet packet of the device 2-1 is mapped.
It means to ping. At this time, the terminal 1-8
Transmit all Ethernet packets from
It is necessary to transmit the part excluding (error check bit)
It can be changed according to. The maximum data length (M
If it exceeds TU), the packet is divided and transmitted.
Indicates whether or not there is division, size, etc. as overhead information
Although a flag is required, such a division
Processing commonly performed in packet and ATM cell transmission
Therefore, the description is omitted. By the above encapsulation, the address of the terminal 1-8 is added.
Address of the edge device 2-1.
Link to the sender / receiver terminal address information
Check only terminal addresses in the same group when searching
And significantly reduce search processing and search time
It is possible. Next, the configuration of the edge device 2-1 will be described with reference to FIG.
This will be described with reference to FIG. Reference numeral 6-1 denotes a processor, reference numeral 6
-2 is a data RAM, and 6-3 is a processing program of the processor.
Program memory for storing programs, 6-4 and
And 6-5 are Ethernet interfaces, and 6-6 is
It is a bus. Packet from terminal 1-8 is Ethernet
Data RA from the interface 6-4 via the bus 6-6
Using M6-2 as a buffer, the processor 6-1
Encapsulated, Ethernet interface 6
5 to the center processing device 3. The packet from the center processing unit 3 is an Ethernet
Similarly via the bus 6-6 from the net interface 6-5
The processor 6 uses the data RAM 6-2 as a buffer.
-1. Next, FIG. 3 shows the configuration of the node section 2-3.
It will be described with reference to FIG. Reference numeral 7-1 denotes a processor, and reference numeral 7-
2 is a data RAM, and 7-3 is a processing processor of the processor.
Program memory for storing the program
The Ethernet interface, reference numeral 7-5 is a bus. end
Packet from end 1-8 is Ethernet interface
7-4 via the bus 7-5.
Filtering in the processor 7-1.
Encapsulated and Ethernet interface
To the server 7-4. (First Embodiment) The first embodiment of the present invention is shown in FIG.
This will be described with reference to FIG. FIG. 5 shows a terminal (labeled PC).
S) Transmission format of unicast packet between 1 and 8
FIG. FIG. 6 shows a terminal (P) according to the first embodiment of the present invention.
C) Transmission format of broadcast packet between 1-8
It is a figure showing a mat. FIG. 7 shows an edge device (described as LEC).
2-1) and the management unit (referred to as RMS) 2-2.
FIG. 3 is a diagram showing a transmission format of a multicast packet.
You. FIG. 8 shows the configuration of the edge device (LEC) 2-1 to the management unit (R).
MS) Transmission of broadcast packets to 2-2
It is a figure showing a format. FIG. 9 shows a first embodiment of the present invention.
Management unit (RMS) 2-2 to edge device (LEC) 2
Transmission format for broadcast packets between -1
FIG. Each format is an Ethernet packet format.
Assuming the case, only the address information part of the header information
Is shown. Other header information (protocol type, etc.)
The description is omitted. First, user information performed between terminals 1-8
Packets and broadcasts for sending and receiving packets
Explain the transmission format of cast packets.
You. In FIG. 5, unicast from terminal 1-8
Packet (PC-B, PC-A) is the edge device 2-1.
And the transmission source is the edge device 2-1,
The destination is the Ethernet packet (RSN) of the node unit 2-3.
-1, LEC-1, PC-B, PC-A)
Transferred to the side. Upon receiving this, the node unit 2-3 receives the message.
Grouping of sending and receiving address information of packetized packets
The destination terminal 1-8 compares the information with the information and if the group is the same,
Ethernet packet addressed to the connected edge device 2-1
(LEC-2, RSN @ 1, PC-B, PC-A)
And transfer it to the user side. Received this
In the edge device 2-1, the encapsulated packet (PC
-B, PC-A) and take out Ethernet interface
Transfer to the subordinate terminal 1-8 via the source. In FIG. 6, the broadcast from terminal 1-8
The last packet (BC, PC-A) is sent to the edge device 2-1.
And the transmission source is the edge device 2-1,
The destination is a unicast Ethernet
With a socket (RSN-1, LEC-1, BC, PC-A)
And transferred to the center. Node unit 2 that has received this
In -3, the address information of the encapsulated packet is grouped.
Number that matches the loop information and corresponds to the number of groups to which it belongs
Encapsulation in broadcast ethernet packets
And packet identification information (group
Ethernet ID of the broadcast to which
Ket (BC, RSN-1, ID-1 to k, BC, PC
-Transfer to the user side as A). The edge that received this
Device 2-1 encapsulates the Ethernet packet.
Take out the group, check the group ID,
Via Ethernet interface
Broadcast packet (B
C, PC-A). Discard if not affiliated
You. Next, the edge device 2-1 and the management unit 2-2
Information and other control of terminal 1-8 performed between
Unicast packets for sending and receiving information packets
And transmission format of broadcast packets
Will be described. In FIG. 7, the unit from the edge device 2-1 is
The cast packet is captured by the edge device 2-1 itself.
Cellular, destination is Ethernet packet of node section 2-3
(RMS-1, LEC-1, RMS-1, LEC-
Transferred to the center side as 1). No receiving this
In the loading section 2-3, the encapsulated packet (RMS-
1, LEC-1), and send and receive address information
Group information, and if the group is the same, the packet (R
MS-1 and LEC-1) to the center LAN 1-7
You. Management unit 2-2 assumes a general-purpose workstation
Then, it is encapsulated because it is directly connected to the center LAN 1-7.
Transfer without. From the management unit 2-2 to the edge device 2-1
Unicast communication is performed in the reverse procedure. Note that
And the management unit 2-2 are reserved as the same group.
To register. In FIG. 8, the blow from the edge device 2-1 is shown.
The multicast packet is sent to the edge device 2-1 itself.
Encapsulated and broadcast Ethernet packets
(BC, LEC-1, BC, LEC-1)
Transferred to the server. In the node unit 2-3 receiving this,
Takes the encapsulated packet (BC, LEC-1)
And transfers it to the center LAN 1-7 as it is. In FIG. 9, the broadcast from the management unit 2-2 is performed.
The cast packet is encapsulated in the node section 2-3.
(BC, RMS-1, BC, RMS-1)
Group ID (BC, RSN-1, ID, BC, RM
S-1), and is transferred to the edge device 2-1. Receive this
In the edge device 2-1, the encapsulated packet is
(BC, RSN-1, ID, BC, RMS-1)
Out, check the group ID, and check the edge device 2-1.
The body receives. The table of the node section 2-3 has
As shown in Fig. 4, the group identification information and the
Device 2-1 and terminals under the control of each edge device 2-1
1-8 address information is linked, and the terminal address is
Search for edge device 2-1 or group information from
A structure that can be used. These pieces of information are generated by the management unit 2-2.
Is transferred to the node unit 2-3.
Record the information in the table. Also, the edge device 2-1
Is notified of the identification information of the group to which it belongs. (Second Embodiment) The second embodiment of the present invention is shown in FIG.
This will be described with reference to FIG. FIG. 10 shows the second embodiment of the present invention.
Broadcast packet between terminals (PC) 1-8 of the embodiment
FIG. 4 is a diagram showing a transmission format of a packet. Fig. 11
The management unit (RMS) 2-2 of the second embodiment is connected to the edge device.
(LEC) of broadcast packet to 2-1
It is a figure showing a transmission format. Each format is
Assuming the case of Ethernet packets, the header information
Only the address information part is shown. Other header information (P
Protocol type etc.) are omitted. Note that a unicast packet between the terminals 1 to 8 is
Transmission format, edge device 2-1 and management unit 2-
Transmission format of the unicast packet between the two,
Broadcast from the edge device 2-1 to the management unit 2-2
The packet transmission format is the same as that of the first embodiment of the present invention.
Through. First, user information performed between terminals 1-8
For sending and receiving broadcast packets
The mat will be described. In FIG. 10, broad from terminal 1-8
The cast packet (BC, PC-A) is sent to the edge device 2-
1, the source is the edge device 2-1, the destination is
Is the unicast Ethernet packet of the node 2-3.
(RSN-1, LEC-1, BC, PC-A)
Transferred to the center side. Node section 2-3 receiving this
In the case of the encapsulated packet (BC, PC-A)
The dress information is compared with the group information, and the
Number of unicast Ethernet packets equivalent to
Packet (LEC-2 ~ n, RSN-1, BC, PC-
A) and transfer the packet to each edge device 2-1.
You. Upon receiving this, the edge device 2-1 encapsulates the packet.
Take out the packet (BC, PC-A)
Transfer to the subordinate terminal 1-8 via the packet interface.
You. Next, the edge device 2-1 and the management unit 2-2
Information and other control of terminal 1-8 performed between
Broadcast packets for sending and receiving information packets
The transmission format of the data will be described. In FIG. 11, the blow from the management unit 2-2 is performed.
The multicast packet is sent to all nodes in the node section 2-3.
Unicast Ethernet packet addressed to device 2-1
(LEC-1 ~ n, RMS-1, BC, RMS-1)
Encapsulated and forwarded. The edge device that received this
In the device 2-1, the encapsulated packet (LEC-
1, RMS-1, BC, RMS-1)
Check the original address, and the edge device 2-1 itself receives it
I do. At this time, the packet from the management unit 2-2 is
By setting not to forward to terminal 1-8
Management security is improved. (Third Embodiment) A third embodiment of the present invention is shown in FIG.
This will be described with reference to FIG. FIG. 12 shows a third embodiment of the present invention.
1 is an overall configuration diagram of a loop communication device. Third embodiment of the present invention
Is an optical access system as an access system.
8-1 is an optical terminal unit (ONU),
Reference numeral 8-2 denotes an optical subscriber line, and reference numeral 8-3 denotes an optical distributor (splicer).
8-4 is a subscriber terminating device (SLT / OL).
T). In the optical terminal device 8-1, the mounted line
Card provides an Ethernet interface
You. In addition, the optical network unit 8-1 is used in the optical network unit 8-4.
Is terminated and connected to the center LAN 1-7.
Also for the above access system, the edge
2-1 and the management unit 2-2 on the center LAN 1-7 side.
By installing cable section 2-3, cable modem system
The present invention can be implemented as in the case of a system. like this
In addition, according to the present invention, the edge device 2 is connected to the environment connected to the LAN.
-1, connecting the management unit 2-2 and the node unit 2-3.
And make it easier to build a group communication system.
It is possible and can be said that it is versatile. As described above, according to the present invention,
Between terminals connected to edge devices of registered members
Terminal address in group communication that only communicates with
Security with filtering using
Can be Automatic registration of terminal address information
Can improve user convenience.
Wear. Due to limitations on the reach of broadcast packets
To improve security and reduce the processing load on terminals
Can be. Address search processing during address check
In addition, the address processing time can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing an overall configuration of a group communication device according to an embodiment of the present invention. FIG. 2 is a block diagram of a main part of the edge device according to the embodiment of the present invention. FIG. 3 is a block diagram of a main part of a node unit according to the embodiment of the present invention. FIG. 4 is a configuration diagram of a table according to the embodiment of the present invention. FIG. 5 is a diagram showing a transmission format of a unicast packet between terminals. FIG. 6 is a diagram showing a transmission format of a broadcast packet between terminals according to the first embodiment of the present invention. FIG. 7 is a diagram showing a transmission format of a unicast packet between an edge device and a management unit. FIG. 8 is a diagram showing a transmission format of a broadcast packet from an edge device to a management unit. FIG. 9 is a diagram showing a transmission format of a broadcast packet from the management unit to the edge device according to the first embodiment of the present invention. FIG. 10 is a diagram showing a transmission format of a broadcast packet between terminals according to the second embodiment of the present invention. FIG. 11 is a diagram showing a transmission format of a broadcast packet from a management unit to an edge device according to the second embodiment of the present invention. FIG. 12 is an overall configuration diagram of a group communication device according to a third embodiment of the present invention. FIG. 13 is an overall configuration diagram of a conventional group communication device. [Description of Signs] 1-1, 1-6 Cable Modem 1-2 Subscriber System 1-3 Relay Amplifier 1-4 Ethernet Interface 1-5 Headend 1-7 Center LAN 1-8 Terminal 1-9 LAN Switch 2-1 Edge device 2-2 Management unit 2-3 Node unit 3 Center processing unit 8-1 Optical termination unit 8-2 Optical subscriber line 8-3 Optical distributor 8-4 Subscriber termination unit

   ────────────────────────────────────────────────── ─── Continuation of front page       (56) References Kazunari Irie Outside, Regional Information Network               Group management in system, electronic information               IEICE Technical Report, Japan, Electronic Information               The Institute of Information and Communication Engineers, October 2, 1997, Vo               l. 96 No. 165, p. 21-26                 Chizen Hayase Outside, local information by ATM               Examination and projection of network system configuration method               ITE Technical Report, Japan, Film               Image Information and Media Society, December 11, 1997,               Vol. 22 No. 77, p. 21-26                 Koichi Shuto Outside, Regional Information Network               System group management server and roe               Development and characteristics of video cards,               IEICE Technical Report, Japan, Video Information               Society of Asia, January 6, 1998, Vo               l. 21 No. 77, p. 9-14

Claims (1)

(57) Claims 1. A large number of terminals, a center processing device accommodating the terminals via a communication line, and one or more of the terminals inserted into the communication line. An edge device, wherein the edge device is assigned to a plurality of groups, and comprises group communication means for allowing transmission and reception of packets between terminals connected to the edge device belonging to the same group, wherein the group communication means comprises: Said included in the frame
Packets addressed to all terminals belonging to the same group
Means for determining whether the packet is a load cast packet
And the determination result of this determination means is
The broadcast packet
The frame containing a unicast Ethernet packet
Encapsulated in the same group, and
A group communication device comprising: means for transmitting data to each of the group devices.