JP3449542B2 - MAC frame transfer method and frame transfer system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a MAC frame transfer method and system, and relates to an Ethernet (Ehternet) which is commonly used in a premises such as LAN or WAN.
Standard) and IEEE 1394-199 enabling high-speed transfer
The present invention relates to a MAC frame transfer method and system capable of communicating with each other.

[0002]

2. Description of the Related Art As an interface standard for connecting a computer and peripheral devices, IEEE1394 is a USB (Un
iversal Serial Bus) is expected as a new computer interface along with the interface. I
EEE 1394-1995 defines data transfer rates of 100 Mbps, 200 Mbps, and 400 Mbps, supports isochronous (isochronous) transfer method, asynchronous transfer method, broadcast transfer method, and the like, and refers to individual devices as nodes, and a maximum of 63
Nodes can be connected, hot plug-ins, plug-ins
Compatible with and play, it can be connected with a daisy chain or tree structure. Also, in IEEE 1394, unlike USB, each node is in an equal position, so it is possible to connect video equipment such as digital video regardless of the presence of a computer, and a wide bandwidth guaranteed by the isochronous transfer method. Is suitable for transferring multimedia data. Furthermore, increasing the transmission distance,
An improved version of P1394a has also been proposed in response to the next-generation IEEE 1394 that has a higher data transfer rate.

For the above reasons, the IEEE 1394 has attracted attention as one of the media to which various digital devices can be connected. As one form, I
Although it is possible to connect by EEE1394 and perform data communication, connection of computers in a current LAN (Local Area Network) is performed by Ethernet (Ethe
rnet) is the mainstream, so terminals with existing Ethernet ports (hereafter referred to as Ethernet terminals)
There are many. Therefore, it is necessary to connect these Ethernet terminals to a network using the 1394 bus so that they can communicate with each other.

The high-performance serial bus standardized by IEEE 1394-1995 is a standard suitable for multimedia data transfer which requires bandwidth guarantee of video and audio and real-time property. . Even after being standardized, this standard is being considered for longer transmission distances and faster data transfer rates.It is used not only for connecting video equipment or video equipment and computers, but also for computers. The connection is evolving.

However, the current LAN (Local Area Network)
rk), the connection between computers in Ethernet (Ethernet) is the mainstream, so there are many terminals with existing Ethernet ports (hereinafter, Ethernet terminals). Therefore, it is necessary to connect these Ethernet terminals to a network using the 1394 bus so that they can communicate with each other.

[0006] As one method of solving this problem, JP-A 10-285204 discloses (hereinafter, Document 1) is described in, how to use the gateway computer interconnecting the Ethernet network and the 1394 network is there.

This reference 1 discloses a 1394 network medium, a plurality of host computers connected to the 1394 network medium, a second network medium such as an Ethernet medium, and a plurality of second computer connected to the second network medium. Host computer and a link layer gateway computer connected to the first and second networks, the link layer gateway computer being selected from one of a plurality of host computers connected to the 1394 network medium. It is described that a data packet from a source host computer is communicated with one of a plurality of host computers connected to a second network medium to a destination host computer, and vice versa. ing.

[0008]

However, in a network in which a plurality of gateway computers described in Document 1 are arranged on a 1394 bus, communication between Ethernet terminals connected to each Ethernet is performed by using a network layer protocol of IP. (Internet Protocol) only, and other network layer protocols are described as exceptional processing, and no specific solution is described.

Further, JP-A-11-32064 Publication (hereinafter, Document 2) an IP processing unit and an address resolution protocol implemented in the Ethernet as described in ARP
(Address Resolution Protocol) processing unit and IEEE
The same network configuration as in FIG. 1 can be obtained by adding an Ethernet port to a communication protocol processing device that can be mounted on a node conforming to E1394 as it is and can be used for mutual communication as it is. It is described that it is possible.

In this publication, there is provided a communication protocol processing device mounted on a node connected to an IEEE 1394-compliant bus, which includes a frame processing means for processing a frame compliant with Ethernet or IEEE 802.3, a frame header and an IEEE 1394. A header conversion means for converting a packet header, and converts a 48-bit transmission destination MAC address in the frame header into a 16-bit transmission destination IEEE 1394 node ID and a 32-bit lower address in the IEEE 1394 packet header The most significant bit of the address is bit-extended and IE
By converting to the EE1394 offset address, the data link means, the IP processing means and the ARP processing means implemented in the existing Ethernet are used, and only the header conversion means is newly added, so that the IEEE13 is easily achieved.
It is said that it is possible to construct a communication protocol processing device that performs IP packet communication between 94 nodes.

However, in the same publication, the IP protocol is indispensable as the protocol of the network layer, as in Reference 1.

Therefore, according to the present invention, a MAC frame transmitted from an Ethernet terminal is transferred using the IEEE 1394 bus, so that Ethernet terminals can communicate with each other via the IEEE 1394 bus independent of the protocol of the network layer. It is what

[0013]

A MAC frame transfer method according to the present invention is standardized in IEEE 1394-1995.
Using the IEEE 1394 serial bus
MAC frame standardized by EEE802.3
A method of transporting multiple Ethernet ports and
For multiple relay devices with IEEE 1394 ports
The IEEE1394 port between the relay devices.
Connected by E1394 serial bus, and among the above
By connecting the terminal to the Ethernet port of the relay device,
Therefore, for each terminal, a plurality of terminals are connected to the IEEE.
The relay device, which is connected via an E1394 serial bus
To each Ethernet port of its own repeater
The first table in which the address of the connected terminal is registered.
And connected to the Ethernet port of another relay device.
The second table in which the addresses of
And the relay device receives the MAC frame from the terminal.
If the transfer source address included in the MAC frame is
Address, transfer destination address and the first and second tables
MA received based on the address information registered in
The C frame is transferred to the transfer destination terminal .

The MAC frame transfer system according to the present invention is also
The stem is standardized in IEEE 1394-1995
Using the IEEE 1394 serial bus
Transfers MAC frames standardized in 802.3
System with multiple Ethernet ports and I
Including a plurality of relay devices having an EEE1394 port,
IEEE1 is between the IEEE1394 ports of the relay device.
394 serial bus connected, and a plurality of relays
By connecting a terminal to the Ethernet port of the device
A plurality of terminals for each terminal
The relay device connected via a 1394 serial bus
To each Ethernet port of its own repeater
The first table in which the address of the connected terminal is registered.
And connected to the Ethernet port of another relay device.
The second table in which the addresses of
And the relay device receives a MAC frame from the terminal.
If it is received, the transfer source address included in the MAC frame
Address, transfer destination address and the first and second tables
MA received based on the address information registered in
It is characterized by having means for transferring the C frame to the transfer destination terminal .

Further, the present invention has begun to be used as an interface between devices and is a high-performance serial bus standardized by IEEE 1394-1995, which has been de facto standardized in recent years (hereinafter referred to as 1394).
It is a transmission control technology that is essential for LANs using a bus) and is standardized by IEEE802.3 used for Ethernet shown in FIG. 5 in access control for allowing multiple nodes to jointly use a local cable smoothly. MAC
(Media Access Control) A method of transferring a frame.

In addition, in the MAC frame transfer method of the present invention, referring to FIG. 1, by connecting the installed bridges 1 to 4 by an IEEE 1394 bus, a terminal having an Ethernet port connected to each bridge. Communication (hereinafter referred to as an Ethernet terminal) independent of the network layer protocol is possible.

In the data transfer method according to the present invention, when the bridge receives the first MAC frame sent from the Ethernet terminal, the MAC address of the terminal and the information of the connected port are used as a terminal registration packet.
Broadcast to each bridge on the 1394 bus.
With this terminal registration packet, each bridge can obtain information on the connection destinations of all Ethernet terminals. Based on this information, the bridge identifies the transfer destination of the MAC frame transmitted from the Ethernet terminal from the destination MAC address included in the MAC frame. When the transfer destination is the Ethernet port of another bridge, M is transferred to the specified bridge by asynchronous asynchronous transfer, which is one of the transfer methods of the 1394 bus.
Send a packet containing an AC frame. When the transmission destinations are the terminals of the same bridge, the MAC frame is transmitted to the specified Ethernet port. When the transmission destination cannot be specified from the transmission destination MAC address, it is broadcast to the 1394 bus and each Ethernet port.

By using this device, terminals having Ethernet ports can be connected to each other via the 1394 bus without depending on the protocol of the network layer.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described.
A detailed description will be given with reference to the drawings.

[First Embodiment] (1) Description of Configuration Referring to FIG. 1, a bridge 1 which is a relay device according to the present embodiment is an IEEE which is a serial bus together with other bridges.
It is one component of the frame transfer system connected by E1394-1995.

In FIG. 1, the bridge 1 has a plurality of Ethernet ports and 1394 ports, and the Ethernet ports are connected to terminals 1-1 and 1 via Ethernet.
-2 is connected. Similarly, bridge 2 has terminal 2
-1 and 2-2, bridge 3 has terminals 3-1 and 3
-2, 3-3, terminals 4-1 and 4-2 on the bridge 4
Are connected respectively. Each terminal has a MAC address M
A1-1, MA1-2, MA2-1, etc. are provided, and the MAC address is discriminated whether it is unicast or multicast at the first bit, universal or local address at the second bit, and 3 to 24 bits. Shows the code of the computer maker name, and the code which is set by the computer maker in 25 to 48 bits is given a unique number. The bridges 1 to 4 have node IDs: N1, N2, ...
, And port IDs: P1, P2, ... Are assigned as Ethernet ports connected to each terminal.

The bridges 1 to 4 are connected by a 1394 bus. Here, the bridges 1 to 4 are two LAs.
A device that connects N, reads the destination address included in the packet data on the LAN, compares it with the address list stored by the bridge, and if the destination is outside the bridge LAN, sends the packet and Ignore if on LAN. In this way, the bridge controls the traffic of packets and prevents unnecessary packets from being sent out.
It has the role of reducing the number of packets flowing through the entire AN system and maintaining efficiency. The bridge includes a local bridge and a remote bridge. The former is used to connect LANs in the premises, and the latter is used to connect LANs in remote areas via a telephone line, ISDN, dedicated line, or the like. .

FIG. 2 is a block diagram showing a configuration example of a bridge in the embodiment of the present invention. Referring to FIG. 2, the bridge 1 includes an Ethernet interface 10
And an IEEE 1394 interface 20 and a packet transfer unit 30.

Further, the packet transfer unit 30 receives the received MA
C frame processing unit 31 and Ethernet terminal table 3
2, a 1394 terminal table 33, a reception 1394 packet processing unit 34, and a fragment / reassembly unit 35.
Consists of.

Since the bridges 2 to 4 in FIG. 1 have the same structure as the bridge 1, the description of the bridges 2 to 4 will be omitted.

Here, the Ethernet interface 1
0 has a plurality of Ethernet ports to which terminals having Ethernet ports can be connected. Ethernet interface
The case 10 performs a reception process of passing the MAC frame transmitted from the terminal shown in FIG. 5 and the number uniquely assigned to the received port (hereinafter referred to as a port ID) to the reception MAC frame processing unit 31. . Here, the MAC frame defined in IEEE802.3 shown in FIG.
7-octet preamble for announcing the start of a frame and 1-octet SFD for the actual start of a frame
(Start Frame Delimiter), destination MAC address of 6 octets indicating the destination of the frame, source MAC address of 6 octets indicating the source of the frame, and frame length of 2 octets indicating the data length and frame type. / a frame type, and from 46 to 1500 octets of data, and the pad, four octets of data confirmed FCS (frame check Sequence), are included and the extension for the extension.

Further, the reception MAC frame processing unit 31 and the reception 1394 packet processing unit 34 perform a transmission process of transmitting a MAC frame from the Ethernet port having the designated port ID.

IEEE 1394 interface 20
Has a plurality of IEEE 1394 interfaces for connecting the bridges with a 1394 bus, and fragments / reassembles the packet of the IEEE 1394 standard asynchronous transfer (hereinafter, referred to as asynchronous packet) transmitted from another bridge. And a transmission process of transmitting an asynchronous packet in response to a transmission request from the fragment / reassembly unit 35. Further, it detects a bus reset on the 1394 bus and notifies the reception 1394 packet processing unit 34 of the bus reset.

When the MAC frame and the port ID of the receiving port are delivered from the Ethernet interface 10, the reception MAC frame processing unit 31 uses the destination MAC address included in the MAC frame as a key, and the Ethernet terminal table 32 and the 1394 terminal table 33. To determine the destination of the MAC frame and make a transmission request to the Ethernet interface 10 or the fragment / reassembly unit 35. Further, the reception MAC frame processing unit 31 updates the Ethernet terminal table 32 and, with respect to the fragment / reassembly unit 35,
A transmission request for the terminal registration packet 80 shown in FIG. 8 is made.
FIG. 8 shows the format of the terminal registration packet 80, which is composed of a 48-bit MAC address of 4 octets and a port-specific offset address (48 bits).

As shown in FIG. 9, the Ethernet terminal table 32 includes the MAC address (MA1-1, MA1-2, etc.) of the terminal connected to the Ethernet port and the port ID of the Ethernet port to which the terminal is connected.
(P1, P2, etc.), which is a table of terminals connected to the Ethernet port. The Ethernet terminal table 32 is used when determining the transmission destination of the MAC frame received by the reception MAC frame processing unit 31. The entry is registered in the Ethernet terminal table 32 when the reception MAC frame processing unit 31 receives the first MAC frame transmitted from the terminal connected to the Ethernet port. Taking the configuration in FIG. 1 as an example, FIG. 9 is an Ethernet terminal table of the bridge 1, in which the terminal 1-1 having the MAC address MA1-1 and the terminal 1-2 having the MAC address MA1-2 are ports. It indicates that the ID is connected to the Ethernet ports of P1 and P4.

Next, as shown in FIG. 10, the 1394 terminal table 33 stores, for the bridge 1, the MAC address of the terminal connected to the Ethernet port of the other bridge, the node ID in the IEEE 1394 of the connected bridge, and It is a table composed of offset addresses used for asynchronous transfer assigned to the Ethernet port, and is a list of terminals connected to other bridges on the 1394 bus. 139
The 4-terminal table 33 includes the reception MAC frame processing unit 31.
Used in determining the destination of the MAC frame received by the. Registration of an entry in the 1394 terminal table 33 is performed when the reception 1394 packet processing unit 34 receives a terminal registration packet from the 1394 interface. Further, when a bus reset occurs on the 1394 bus, the node ID of the bridge may change, so all the entries in the 1394 terminal table 33 are erased by the reception 1394 packet processing unit 34.

Taking the configuration in FIG. 1 as an example, FIG.
Is the 1394 terminal table for bridge 1, and the first two entries are for bridge 2 with node ID N2.
In the figure, terminals 2-1 and 2-2 having MA2-1 and MA2-2 as MAC addresses are connected to the Ethernet ports to which the offset addresses OA2 and OA4 are assigned, respectively. Below, regarding the terminals connected to the bridges 3 to 4 on the 1394 bus,
An entry including a MAC address, a node ID, and an offset address is lined up.

The receiving 1394 packet processor 34 receives the MAC frame 4 from the fragment / reassembler 35.
When 0 or the terminal registration packet 80 and the source ID and the destination offset address are delivered, the Ethernet port that transmits the MAC frame is determined from the destination offset address, and a request to transmit the MAC frame is issued to the Ethernet interface 10. . Also, 1394
When a registration packet is received, the terminal is registered in the terminal table 33, and when a bus reset notification is received from the 1394 interface 20, all entries are deleted.

The fragment / reassemble unit 35 divides the MAC frame or the terminal registration packet according to a predetermined maximum packet length that can be received by the destination bridge and transfers the transfer packet header shown in FIG. Fragment processing that adds 70 is performed, and 1394
A packet transmission request is issued to the interface 20.

Here, the transfer packet header shown in FIG. 7 includes a 2-bit fragment flag, a 2-bit packet type, a 6-bit sequence number, an 11-bit buffer size, and an 11-bit fragment offset. It consists of 32 bits in total.

Further, based on the information of the transfer packet header 70 of the data divided by the transmission source, a reassembling process for reconstructing a MAC frame or a terminal registration packet is performed, and together with the transmission source ID and the transmission destination offset address,
The reception 1394 packet processing unit 34 delivers the packet. When it is necessary to send a response packet to an asynchronous write request, the 1394 interface 20
Make a request to send a response packet.

Next, the structure of a packet on the 1394 bus will be described with reference to FIGS. As shown in FIG.
The transfer packet header 70 is added to the MAC frame and the terminal registration packet, and the IEEE 1394-199 is added.
It is transmitted to each bridge as a write request packet of the data block specified in 5.

The transfer packet header 70 includes a fragment flag 71, a packet type 72, and a sequence number 7.
3, buffer size 74, fragment offset 75
Composed of.

The fragment flag 71 indicates the fragment state of the MAC frame or the terminal registration packet included in the asynchronous packet, and indicates four types: no fragment, first fragment, intermediate fragment, and last fragment.

The packet type 72 is asynchronous.
It is a bit indicating whether the data included in the packet is a MAC frame or a terminal registration packet.

The sequence number 73 is a number individually assigned to the transmission request from the reception MAC frame processing unit 31. The sequence number starts from 0, and for each solicitation sent from a bridge to another bridge,
They are added one by one, and if the value exceeds the expressible value, it returns to 0.

The buffer size 74 indicates the data length of the MAC frame or terminal registration packet before being fragmented.

The fragment offset 75 indicates where the head of the data contained in the asynchronous packet is located from the head of the MAC frame or the registration packet before being fragmented.

The structure of the terminal registration packet 80 is shown in FIG. The terminal registration packet 80 is composed of the source MAC address of the MAC frame and the offset address assigned to the Ethernet port to which the source terminal is connected. As the node ID required for updating the 1394 terminal table 90, the sender ID of the header of the asynchronous packet shown in FIG. 6 is used.

(2) Description of Operation FIG. 2 shows the operation of the packet transfer unit 30 of this embodiment.
This will be described in detail with reference to FIGS.

The operation of the reception MAC frame processing section 31 will be described with reference to FIGS. 2 and 3. FIG. 3 shows the reception MA
6 is a flowchart showing an operation when the C frame processing unit 31 receives the MAC frame and the reception port ID shown in FIG. 5 from the Ethernet interface 10.

As shown in FIG. 3, the operation of the reception MAC frame processing unit 31 is performed in the terminal registration phase (steps A1 to A1).
A3) and the packet transfer phase (steps A4 to A1)
It is divided into 0).

First, the terminal registration phase will be described. The reception MAC frame processing unit 31 in FIG. 2 searches the Ethernet terminal table 32 using the source MAC address of the MAC frame passed from the Ethernet interface 10 as a key (step A in FIG. 3).
1).

As a result of the search, when the source MAC address is present in the Ethernet terminal table 32, the packet transfer phase (phase starting from step A4 in FIG. 3) is entered. If it does not exist, the fragment / reassemble unit 35 is requested to broadcast the terminal registration packet shown in FIG. 8 to other nodes connected to the 1394 bus.

The terminal registration packet is transmitted by using a data block write request to an offset address determined in advance for the terminal registration packet by asynchronous transfer. Callee I at this time
D uses the broadcast address (step A2).

Next, the source MAC address and the ID indicating the Ethernet port to which the terminal is connected are added / registered as one entry in the Ethernet terminal table 32 (step A3).

In the packet transfer phase (step A)
4 to A10) will be described. The reception MAC frame processing unit 31 determines whether the destination MAC address of the MAC frame is a broadcast address (step A4).

When the destination MAC address is a broadcast address, it broadcasts to other bridges and Ethernet on the 1394 bus. Thirteen
For the broadcast to the 94 bus, a broadcast address is designated as a destination node ID with respect to an offset address that is fixedly assigned in advance and determined, for example, the first two bits of the address bit are "00". This is performed using a data block write request (step A9).

Broadcasting to the Ethernet is performed by a request to the Ethernet interface 10 to transmit a MAC frame from all Ethernet ports (step A10).

At step A4, if the destination MAC address is not a broadcast address, the destination MA
Ethernet terminal table 3 with C address as key
It is searched whether or not there is a destination MAC address in 2 (step A5). If the destination MAC address to be searched exists in the Ethernet terminal table 32, the port ID written in the Ethernet terminal table 32
The Ethernet interface 10 is requested to transmit a MAC frame to the Ethernet port (step A6).

In step A5, if the destination MAC address to be searched does not exist in the Ethernet terminal table 32, the reception MAC frame processing unit 31 determines the destination M.
Using the AC address as a key, the 1394 terminal table 33
Is searched (step A7). Destination MAC to search
When the address is present in the 1394 terminal table 33, the destination ID and offset address for the destination MAC address are specified, and the MAC frame is transmitted to another bridge as a data block write request. The request is sent to the fragment / reassemble unit 35 (step A8).

At step A7, the 1394 terminal table 3
If the transmission MAC address corresponding to No. 3 does not exist, it is regarded as a packet in which the connection location of the destination terminal is unknown, and all Ethernet ports and others on the 1394 bus are processed in the same manner as in steps A9 to A10 described above. Request a broadcast to the bridge (step A9,
A10).

Next, referring to FIGS. 2 and 4, the reception 13
The operation of the 94 packet processing unit 34 will be described. Figure 4
The reception 1394 packet processing unit 34 transmits the data packet transmitted from another bridge and input via the 1394 interface 20 to the MAC frame or terminal registration packet reassembled by the fragment / reassembly unit 35, and the transmission. 9 is a flowchart showing an operation when an original ID and a destination offset address are delivered.

With respect to the received data packet, it is determined whether the destination offset address is an offset address for the Ethernet port which is assigned in advance (step B1). If the offset address is assigned to the Ethernet port, the MAC address is assigned to the Ethernet port corresponding to the offset address.
The Ethernet interface 10 is requested to transmit the frame (step B2).

If the destination offset address is not the offset address assigned to the Ethernet port, it is determined whether the destination offset address is the offset address assigned to a predetermined broadcast (step B3). . If the offset address is assigned for broadcasting, the Ethernet interface 10 is requested to transmit the MAC frame to all Ethernet ports (step B4).

If the destination offset address is not the offset address assigned for broadcasting, it is determined whether the destination offset address is the offset address assigned for the terminal registration packet (step B5). If the offset address is for the terminal registration packet, the 1394 terminal table 3
An entry consisting of the MAC address, the sender ID, and the offset address assigned to the connected Ethernet port is added and registered in step 3 (step B).
6).

Further, the receiving 1394 packet processing unit 34
However, when a bus reset notification is received from the 1394 interface 20, all entries in the 1394 terminal table are erased.

Next, the fragment / reassemble unit 35
The operation of will be described. Fragment / reassemble
The unit 35 performs fragment processing and reassembly processing of the terminal registration packet and the MAC frame.

As the fragment processing, the transfer packet header 70 shown in FIG. 7 is added to the MAC frame or the terminal registration packet requested to be transmitted from the reception MAC frame processing section 31.

At this time, the data length of the transfer packet header 70 and the data block write request packet shown in FIG. 6 including the terminal registration packet or the MAC frame is the maximum reception data length of the 1394 port of the transmission destination bridge. If it exceeds, fragment processing is performed.
In the fragment processing, the MAC frame or the terminal registration packet is divided, and the transfer packet header 70 is divided into each.
Is added and converted into multiple write requests. When the fragment processing is completed, a transmission request is made to the 1394 interface 20. If the maximum received data length is not exceeded, fragment processing is not performed, the transfer packet header 70 is added to the terminal registration packet or MAC frame, and a transmission request is made to the 1394 interface 20 as a write request.

As the reassembling process, the sequence number 73, the buffer size 74, and the fragment offset 75 for the packet indicating the first, middle, or last fragmented fragment of the fragment flag 71 of the transfer packet header 70 shown in FIG. The MAC frame or terminal registration packet that has been fragmented and transferred based on the above is reassembled and passed to the reception 1394 packet processing unit 34 as a non-fragmented packet together with the transmission source ID and the transmission destination offset address.

As described above, among the bridges connected to the Ethernet, the other bridges are IEEE139
4 When operating as a system connected by a bus, the fragment / reassemble unit 3 of the source bridge
5, the MAC frame and the terminal registration packet are divided according to the maximum received data length of the 1394 port of the transmission destination bridge, and the MAC frame and the terminal registration packet are reassembled in the fragment / reassembly section 35 of the transmission destination bridge. The network is operational.

As described above, among the bridges connected to the Ethernet, the other bridges are IEEE139
When operating as a system connected by the standard of No. 4, the reception MAC is used as fragment / reassembly processing corresponding to the MAC address in each bridge.
The frame processing unit 31 re-attaches the destination MAC frame, and the reception 1394 packet processing unit 34 re-attaches the correct destination to the Ethernet MAC frame, so that the network operation operates smoothly.

In the above embodiment, the designation of the broadcast transfer from the terminal has been described. However, for the broadcast which is a wide range of broadcast transfers, the multicast transfer for the purpose of transfer in a specific group is also performed.
It may be operated in the above-mentioned broadcast manner.

[Second Embodiment] Next, a second embodiment of the present invention will be described. In the present embodiment, referring to FIG. 11, in one bridge, a HUB or the like is connected to an Ethernet port of the bridge, a plurality of HUBs and a plurality of terminals are connected to one Ethernet port, and a plurality of terminals are connected to the HUB. Can be connected.

In this embodiment, the reception MAC frame processing unit 31 stores a plurality of H's in the Ethernet terminal table 32.
In the case of the Ethernet port connected to the UB, a plurality of entries having the same port ID are registered. Similarly, the reception 1394 is received by the 1394 terminal table 33.
The packet processing unit 34 registers a plurality of entries having the same set of node ID and offset address.

In this embodiment, the fragment / reassemble unit 35 is added to the IEEE1394 interface 20.
When a broadcast transmission request is received from
GASP (Global Asynchronous Stream Pac shown in 2)
ket) A transmission function for performing asynchronous stream transfer in GET format and GASP format are analyzed to confirm the data length, tag, channel number, transaction code, synchronization code, header CRC, and a predetermined unique A reception function is added to receive only the ID 112 and the version packet and to pass the source ID 112, the transfer packet header 70, the terminal registration packet or the MAC frame to the fragment / reassemble unit 35.

With the addition of this function, the GA shown in FIG.
Using the SP format, the terminal registration packet is broadcast (step A2 in FIG. 3) or the destination MA
A MAC frame whose C address is a broadcast address can be broadcast (step A9 in FIG. 3).

GASP format 11 shown in FIG.
0 is a format that is being studied as an extension of the IEEE 1394-1995 standard, and is one of the asynchronous stream packet formats used when transmitting data using asynchronous stream transfer. In the GASP format 110, the first two quadlets of the data field of the asynchronous stream packet are used as the source node ID, unique ID, and version.

In this embodiment, broadcasting is performed using the unique ID and version assigned to the present invention. It is assumed that the channel number used for broadcasting has been decided in advance. It should be noted that even in the case of a multicast in which a specific address code is added to the destination address, it can be handled almost in the same manner as the wide range broadcast transfer.

In the above embodiment, the IE at home is
Although the EE1394 is not particularly described, the contents described in the above embodiment may be used for home use. In the home system, for example, a bridge is provided on each of the first and second floors of the two-story building, and they are connected by IEEE 1394. The first floor has a refrigerator, a microwave oven, a washing machine, etc. connected to the bridge, and the second floor has By connecting to a personal computer, a printer or the like, it can be used for home. At that time, a public telephone line can be connected to the bridge to make a call via the bridge, and PHS or PDC (Personal Digital Sellu
lar) may be connected wirelessly, and by providing a wireless transceiver unit in at least one port of the bridge,
Wired and wireless networks can be assembled.

[0077]

As described above, according to the present invention, 1
IEEE 1394 for each terminal
Can be connected via a serial bus and can be networked
Communication independent of the layer protocol, IEEE1394
Communication can be performed via a serial bus .

In addition, a device connected on the 1394 bus
A bus reset occurs automatically when a device is added or deleted.
Even if the assigned node ID changes,
A smooth network such as LAN that does not require manual settings
Connected in the work and by IEEE1394-1995
High-speed data communication is possible in
There is .

[Brief description of drawings]

FIG. 1 is an example of a network configuration according to the present invention.

FIG. 2 is an internal block diagram of a relay device (bridge) according to the present invention.

FIG. 3 is a flowchart of a reception MAC frame processing unit according to the present invention.

FIG. 4 is a flowchart of a reception 1394 packet processing unit according to the present invention.

FIG. 5 is a block diagram of a MAC frame according to the present invention.

FIG. 6 is a format of a data block write request packet according to the present invention.

FIG. 7 is a configuration diagram of a transfer packet header according to the present invention.

FIG. 8 is a configuration diagram of a terminal registration packet according to the present invention.

FIG. 9 is a block diagram of an Ethernet terminal table according to the present invention.

FIG. 10 is a block diagram of a terminal table of IEEE 1394-1995 according to the present invention.

FIG. 11 is an Ethernet terminal connection configuration diagram of the second embodiment according to the present invention.

FIG. 12 is a GASP (Global Asynchronous) used in the present invention.
ous Stream Packet) format.

[Explanation of symbols]

1, 2, 3, 4 Bridge 1-1, 1-2, 2-1, 2-2 Terminal 10 Ethernet interface 20 IEEE 1394 interface 30 Packet transfer unit 31 Reception MAC frame processing unit (reception MAC processing unit) 32 Ethernet terminal table 33 1394 Terminal Table 34 Reception 1394 Packet Processing Section (Reception 1394 Processing Section) 35 Fragment / Reassembling Section 40 MAC Frame 60 Data Block Write Request Packet Format 70 Transfer Packet Header 80 Terminal Registration Packet 100 Bridge 101, 102 HUB 100 -1,100-2 Terminal 110 GASP format

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H04L 12/40 H04L 29/04

Claims (7)

(57) [Claims] 1. Standardized in IEEE 1394-1995.
Using the IEEE 1394 serial bus,
Transfers MAC frames standardized by EE802.3
A plurality of Ethernet ports and I
Using multiple relay devices with EEE 1394 ports,
IEEE1 is connected between the IEEE1394 ports of the relay device.
394 serial bus, and a plurality of relay devices
By connecting the terminal to the Ethernet port
For each terminal, a plurality of terminals are provided in the IEEE 1
394 serial bus to connect to the relay device
Connect to the Ethernet port of their own repeater.
The first table in which the address of the connected terminal is registered
Connected to the Ethernet port of another relay device
A second table in which the addresses of
However, the relay device receives a MAC frame from the terminal.
In this case, the transfer source address included in the MAC frame
Address, transfer destination address and the first and second tables
MAC received based on registered address information
MA for transferring a frame to a transfer destination terminal
C frame transfer method. 2. Standardized in IEEE 1394-1995.
Using the IEEE 1394 serial bus,
Transfers MAC frames standardized by EE802.3
Transmission system, which has multiple Ethernet ports and
And a plurality of relay devices each having an IEEE 1394 port.
Only the IEEE1394 port of the relay device is IEEE
Connected by an E1394 serial bus, and
By connecting the terminal to the Ethernet port of the repeater
Therefore, for each terminal, a plurality of terminals are connected to the IE.
Connected via EE1394 serial bus and relay
Each device has its own Ethernet device Ethernet port.
First, the address of the terminal connected to
Connect to the table and the Ethernet port of another relay device
Second table in which addresses of registered terminals are registered
And the relay device is provided with a MAC frame from the terminal.
Is received, the transfer source included in the MAC frame
Address, transfer destination address, and the first and second data
Received based on the address information registered in Bull
A MAC frame transfer system comprising means for transferring a MAC frame to a transfer destination terminal . 3. The relay device receives the MA received from the terminal.
The C frame can be received by the relay device that relays it.
Having a dividing means to divide according to the large packet length
The MAC frame transfer system according to claim 2 , characterized in that 4. The dividing means divides the MAC frame.
The presence or absence of division and the MAC frame after division is divided for each
Information indicating whether it is the beginning, the middle, or the end of
Information, information indicating the data length of the MAC frame before division,
The beginning of the data of the MAC frame after the division is the MAC before the division
Information that indicates where the frame data is located
A contract characterized by adding a transfer packet header containing
The MAC frame transfer system according to claim 3. 5. The relay device is configured to divide the MAC frame into pieces.
Message is received, based on the transfer packet header
MAC frame divided based on the original MAC frame
5. The M according to claim 2 , characterized in that
AC frame transfer system. 6. The relay device comprises a MAC frame from a terminal.
The source address included in the program is the first table.
If it is not registered in the
The data is registered in the first table.
The MAC frame transfer system according to any one of 2 to 5 . 7. The Ethernet port of the relay device,
A HUB with an Ethernet port for multistage connection is connected.
Then, the terminal is connected to the Ethernet port of the HUB.
The MAC frame transfer system according to claim 2 , wherein