JP5074228B2 - Station equipment in passive optical networks. - Google Patents

Description

  The present invention relates to a station apparatus in a passive optical network (PON), and in particular, has a unicast type / broadcast type / multicast type transfer function when transferring a MAC frame using a passive optical network. The present invention relates to a station apparatus in a passive optical network.

  As a first background art in the present invention, ITU-T Recommendation G. There is 984.3 "Gigabit-capable Passive Optical Networks (G-PON): Transmission convergence layer specification". This Recommendation G. According to 984.3, a frame transmission method using a variable length frame called a GEM (G-PON Encapsulation Method) frame as a basic unit is adopted for transmission in the PON section. The GEM frame is a transmission frame in the PON section. It is encapsulated and transmitted. The transmission frame of the PON section is the ITU-T recommendation G.264. In 984.3, GTC (G-PON Transmission Convergence) downstream in the direction of the terminal device (ONT) from the local equipment (OLT; Optical Line Terminal) and the OT in the direction of the OT from the ONT Yes. ITU-T Recommendation G. In the transmission scheme specified in 984.3, the GTC downstream stream in the OLT to ONT direction (downlink transmission direction) is broadcasted to all ONUs, and the GTC upstream frame in the ONT to OLT direction (upstream transmission direction) is: Signals from the respective ONTs are multiplexed and transmitted by time division multiple access (TDMA; Time division Multiple Access). As a feature of this transmission method, the downlink transmission direction is a one-to-many (single OLT vs. multiple ONT), and the uplink transmission direction is a one-to-one (single ONT vs. single OLT) transmission form. . That is, means for transferring the same frame from the OLT to all ONTs is defined, but means for transferring the same frame from one ONT to the OLT and all other ONTs is not defined. The characteristics of this transmission method are the same for the GEM frame encapsulated in the GTC frame.

FIG. 21 shows the recommendation G.1. It is the figure which showed the structure of the GEM frame in 984.3. The GEM frames 70 are sequentially stored and transmitted in the payload of the GTC frame, and a GEM frame boundary is detected at the receiving end, and each GEM frame 70 is extracted. Each GEM frame includes GEM headers 71 and 71-2 to 71-n and GEM payloads 76 and 76-2 to 76-n. The GEM header 71 further includes a PLI field 72, a Port ID field 73, and a PTI (Payload Type). An Indication) field 74 and an HEC field 75. The PLI field 72 stores the byte length of the GEM payload 76-1, the PTI field 74 stores the GEM frame type, and the HEC (Head Error Correction) field 75 stores the error correction code of the GEM header 71. Used for the GEM frame 70 extraction process at the receiving end of the GEM frame. The Port ID field 73 is an area for storing a Port ID that is a connection identification number of the PON section. By referring to this field, the connection of the PON section to which the GEM frame 70 belongs is identified.
FIG. 22 shows a GTC frame that is a basic frame structure of a PON section in which a GEM frame is mounted. The frame in the downlink transmission direction includes header information called PCBd (Physical Control Block Downstream) 95-1 and Payload 95-2, and the GEM frame in the downlink transmission direction is sequentially stored and transmitted in Payload 95-2. Uplink transmission directions are PCBu (Physical Control Block upstream) 97-1, PLOAMu (Physical Layer OAM upstream) 97-2, PLSu (Power Leveling Sequence upstream stream 3D, 3D, DBD) It is transferred in a control field and a frame having Payload 97-5 as a basic configuration. Similarly, the GEM frame is mounted on the Payload 97-5 and transferred in the upstream direction. However, in the uplink transmission direction, the OLT receives time-division multiplexed frames by TDMA control.

Next, as a second technical background, IEEE Std 802.1D ^™ “Media Access Control (MAC) Bridges.” Exists. According to this technical standard, a network device configuration called a MAC bridge connecting between LANs (local area networks) defined by IEEE 802.3 is shown. The MAC bridge described in this technical standard extracts header information of a frame (hereinafter referred to as a MAC frame) input from each interface, and searches a table called Forwarding Database (FDB) based on the extracted information. It has a function to perform. The MAC bridge determines the interface to transfer the MAC frame from the table search result, and executes the frame transfer. In the transfer of MAC frames by the MAC bridge, there are used a transfer form called unicast for transferring frames to only one interface and a transfer form called multicast for transferring MAC frames by copying to a plurality of interfaces. In addition, a special form of multicast is defined in which the MAC frame is transferred to all interfaces other than the interface to which the MAC frame is input, which is called broadcast. Unicast, multicast, and broadcast MAC frames can be identified by the destination MAC address in the MAC frame header. In the Forwarding Database, information on the transfer destination interface is registered for each destination MAC address, and transfer processing is executed based on this information. The destination MAC address registered in the Forwarding Database is maintained and managed by an autonomous learning function by the MAC bridge, various protocols, or maintenance settings. Here, as a feature of the technical standard, it is mentioned that multicast transfer / broadcast transfer is actively used. Therefore, when a network is configured using a MAC bridge, multicast transfer / broadcast transfer is an indispensable function.

  Further, the third technical background will be described. DHCP (Dynamic Host Configuration Protocol) is used in many scenes in order to give an Internet (IP) address to a connected user apparatus on a network using the second background art. DHCP uses MAC broadcast in protocol procedures. Since the MAC broadcast is transferred to all user devices in the network using the second background technology, the user information such as the IP address of each user device is also received by other unrelated user devices. .

  Finally, as a fourth background art, ITU-T Recommendation G. 984.4 “Gigabit-capable Passive Optical Networks (GPON): ONT management and control interface specification” exists. Although this recommendation is not directly related to the present invention, it is called ONT Management and Control Interface (OMCI), which is necessary to implement various settings for the ONT connected from the OLT in the present invention. Stipulates the protocol.

ITU-T Recommendation G. 984.3 "Gigabit-capable Passive Optical Networks (G-PON): Transmission convergence layer specification" IEEE Std 802.1D TM “Media Access Control (MAC) Bridges.” The Internet Engineering Task Force (IETF), Droms, R.A. "Dynamic Host Configuration Protocol", RFC 2131, Bucknell University, March 1997. ITU-T Recommendation G. 984.4 "Gigabit-capable Passive Optical Networks (GPON): ONT management and control interface specification"

  The problem of the present invention is due to the limitation of frame transfer in a network using PON. As described above, transmission by PON is broadcast in the downlink transmission direction, and the same frame can be transferred to all terminal devices. However, the function of transferring the upstream frame from the terminal device side to another terminal device is described in the recommendation G.1. It is not specified in 984.3. However, in a network that transfers the MAC frame, in many cases, multicast transfer / broadcast transfer between arbitrary interfaces is required in addition to frame transfer (unicast transfer) between arbitrary interfaces. For this reason, when a network in a form such as PON is used for MAC frame transfer and is used as a function equivalent to the existing MAC bridge, the upstream frame from the terminal device is unicast transfer / multicast transfer to an arbitrary interface. There is a need to provide a function to transfer / broadcast.

  The problem here is related to the method of using the broadcast property in the downlink transmission direction of the PON section. In the existing MAC frame transfer, the recommendation G. There is no method for controlling the vertically asymmetric frame transfer mode according to 884.3, and a new control method corresponding to this method is required. As described above, in a network device configuring a MAC bridge, a MAC frame input from an arbitrary interface is transferred to another arbitrary interface by any one of unicast transfer / multicast transfer / broadcast transfer. When the MAC bridge function is applied to transmission in the PON section, it must be possible to transfer a MAC frame from a user connected to a terminal device to users under other terminal devices. However, the service provider may operate by suppressing inadvertent MAC frame transfer from a contractual viewpoint such as security and traffic conditions. In particular, regarding MAC frame transfer from a terminal device to another terminal device, information that is inadvertently transferred to a connected person may be transferred. In addition, the upper layer protocol that uses the multicast / broadcast MAC frame may include terminal device address information and the like, and depending on the service conditions and contract contents, this information is prevented from being transferred to others. There is a need. For example, DHCP that assigns an IP address to a subscriber is an example of such an upper protocol. In order to support such a function, it is necessary to transfer the frame after recognizing the transmission characteristics of the PON section. However, since it is outside the provisions of the second background art, there is no clear provision. .

As described above, in the present invention, in the downlink transmission direction, broadcast multicast and one-to-one connection type unicast are possible in the downlink transmission direction, and only one-to-one unicast is available in the uplink transmission direction. It is an object of the present invention to configure a MAC bridge that uses an available PON type network to unicast / multicast / broadcast an upstream frame from a terminal device to an arbitrary interface. In other words, the present invention determines, for example, whether to transfer a unicast / multicast / broadcast MAC frame using a multicast connection / unicast connection / broadcast connection in the PON section by arranging transfer logic. For the purpose. It is another object of the present invention to map a MAC frame, which is determined to be transferred using a multicast connection / unicast connection / broadcast connection in a PON section, to a GEM frame.
It is another object of the present invention to configure a MAC bridge using a PON type network and prevent frame transfer between subscribers not intended by the network manager and multicasting of a PON section including subscriber information.

  In order to solve the above-described problem, a frame transfer processing unit is provided in the OLT which is a station apparatus, and the frame transfer processing unit sets information for recognizing the transfer format of the PON section and transferring the MAC frame. A frame transfer table to enable MAC frame transfer equivalent to a MAC bridge. As a result, the transfer route of the MAC frame input from each subscriber or the station is determined in the station device, and for the multicast / broadcast MAC frame, the necessary number of MAC frames are copied and transferred to the necessary route. It becomes possible to do. The frame forwarding table includes a first control flag area for permitting use of a multicast connection in the PON section, and a second field indicating whether a MAC frame input from a subscriber can be forwarded to another subscriber. A second control flag area is provided for use in determining the MAC frame transfer destination. Thereby, in the case of the unicast, the MAC frame having the destination in the PON section searches for the destination, and at the same time, determines whether the transfer to the subscriber side is permitted by the second control flag. For the multicast / broadcast MAC frame, the availability of the multicast connection in the PON section and the MAC frame copy method are further determined, and the transfer of the MAC frame is executed. As a result, it is possible to prevent a MAC frame from being transferred from a subscriber to other subscribers against the intention of the service provider, and a MAC bridge that actively uses a multicast connection in the PON section. It becomes configurable.

  At the MAC frame level, MAC frames that are multicast / broadcast transferred to each subscriber are also recognized as special frames if they have subscriber information in the higher-level protocol. MAC frame transfer is executed with reference to a special frame transfer table independent of the frame transfer table. At this time, the multicast / broadcast MAC frame is transferred using the unicast connection in the PON section. As a result, even in a higher-level protocol using a multicast / broadcast MAC frame, a MAC frame having subscriber address information can be prevented from being transferred to other unrelated subscribers.

According to the present invention,
A station apparatus, a plurality of terminal apparatuses, and a coupler that joins and diverts a plurality of optical transmission paths from each of the terminal apparatuses and one optical transmission path from the station apparatus, from the station apparatus to the terminal A downlink transmission frame to the apparatus is transmitted from the station apparatus by a single station apparatus to a plurality of terminal apparatuses with a one-to-N logical connection in the terminal apparatus direction (N is 1 or more), and from the terminal apparatus. The upstream transmission frame to the station apparatus is a passive transmission in which signals from each terminal apparatus are multiplexed by time division multiple access through a one-to-one logical bidirectional connection by a single terminal apparatus to a single station apparatus. The station apparatus in an optical network (PON),
Connected to the optical transmission path on the terminal side, terminates the upstream transmission frame, converts the terminal device from a GEM frame, which is a transmission unit in the PON section with the station device, to an intra-device frame, and A subscriber line interface for converting a transmission frame from an in-device frame to a GEM frame;
An intra-station / inter-station interface connected to the intra-station / inter-station transmission path;
A MAC frame transfer processing unit that is connected to the subscriber line interface and the intra-station / inter-station interface and transfers intra-device frames;
For the destination MAC address of the received frame, an intra-device ID that is a transfer path of the MAC frame is registered for each of the subscriber line interface and the intra-station / inter-station interface, and the one-to-N logic A first control flag region indicating that a typical one-way connection can be used for frame transfer, and a second control flag region indicating that frame transfer from the terminal device to another terminal device is prohibited. The frame forwarding table including:
With
The MAC frame transfer processing unit
Upon receiving a MAC frame mounted in an intra-device frame from the subscriber line interface or the intra-station / inter-station interface, a MAC address is extracted from the MAC frame,
The frame transfer table is searched based on the extracted MAC address, and the subscriber line interface and the in-device ID serving as a transfer route to which the MAC frame is to be transferred and / or the intra-station / inter-station interface and the Find the device ID,
If the first control flag area is set in the retrieved data of the frame transfer table, a 1 to N logical connection is used, and if the second control flag area is set, the terminal On condition that frame transfer from the device to the other terminal device is prohibited, the necessary number of MAC frames are copied in accordance with the obtained number of in-device IDs, and the in-device ID is assigned with each in-device ID. Forming and transferring the intra-device frame toward the subscriber line interface and / or the intra-station / inter-station interface which is a transfer route,
The station apparatus in a passive optical network (PON) is provided.

  According to the present invention, in a bridge type network in which a MAC frame is transferred between a subscriber interface and an intra-station / inter-station interface using a network using a PON as a transmission method, the subscriber frame is inadvertently transferred to another subscriber. It is possible to configure a MAC bridge that prevents MAC frames from being transferred and allows a MAC frame to be transferred using a multicast connection in the downlink transmission direction of the PON section. As a result, the existing bridge network can be replaced with a logically equivalent PON network. In addition, it is possible to prevent MAC frame transfer between subscribers unintended by the network administrator, which occurs by using a multicast connection in the PON section.

  Embodiments of a station apparatus in a passive optical network that is an object of the present invention and embodiments of a data transfer method using the station apparatus will be described below with reference to the drawings.

1. PON system

First, the configuration of the PON according to the embodiment to which the present invention is applied will be described.

FIG. 1 shows a PON system connection configuration diagram. This system includes a station apparatus OLT (Optical Line Terminal) 1, terminal apparatuses ONT (Optical Network Terminal) 2-11 to 2-1N, optical fibers 3-1 to 3-M, 5-11 to constitute a passive optical network. 5-1N, a coupler 4-1 for branching a fiber, intra-station / inter-station transmission paths 6-1 to 6-L, terminal-side transmission paths 7-11 to 7-1N, and a device control terminal 8 are provided. The station apparatus 1 includes subscriber line interfaces 10-1 to 10-M, a MAC frame transfer control unit 20, intra-office / inter-station interfaces 30-1 to 30-L, and a control unit 40. The terminal devices 2-11 to 2-1N include optical passive network termination units 50-11 to 50-1N and UNI processing units 60-11 to 60-1N. The station apparatus 1 and the terminal apparatuses 2-11 to 2-1N are connected by an optical fiber 3-1, which is branched into a plurality of optical fibers 5-11 to 5-1N by a coupler 4-1. Further, the device control terminal 8 enables control such as setting via the control line 9.

  The MAC frame input to the intra-station / inter-station interfaces 30-1 to 30-L from the intra-station / inter-station transmission paths 6-1 to 6-L is determined by the MAC frame transfer control unit 20 as the MAC frame transfer destination interface. It is transferred to the subscriber line interfaces 10-1 to 10-M or other intra-station / inter-station interfaces 30-1 to 30-L. The MAC frame transferred to the subscriber line interface 10-1 is mounted on the GEM frame, further multiplexed with the downlink transmission frame in the PON section, and transmitted to the terminal devices 2-11 to 2-1N via the optical fiber 3-1. It is broadcast. The optical passive network termination units 50-11 to 50-1N perform termination processing of the downlink transmission frame in the PON section that has reached each terminal device 2-11 to 2-1N, and extract a GEM frame addressed to the terminal device itself. The GEM frame destined for the own terminal device extracted by the optical passive network termination units 50-11 to 50-1N is converted into a format compatible with the UNI (User Network Interface). Forwarded to In the UNI processing units 60-11 to 60-1N, the MAC frame is extracted from the GEM frame to be output to the terminal side transmission paths 7-11 to 7-1N, and is output to the terminal side transmission paths 7-11 to 7-1N. To do.

The MAC frames in the upstream transmission direction input from the terminal side transmission lines 7-1 to 7-N are subjected to frame termination processing in the UNI processing units 60-11 to 60-1N, and the optical passive network termination units 50-11 to 50-50. -1N. In the optical passive network termination units 50-11 to 50-1N, the arrived MAC frame is mounted on the GEM frame, further assembled into an upstream transmission frame in the PON section, and output to the optical fibers 5-11 to 5-1N. In the uplink transmission direction, in order to share the optical fiber in the PON section between the plurality of terminal apparatuses 2-11 to 2-1N, the transmission frames from the plurality of terminal apparatuses 2-11 to 2-1N are time-division multiple access (TDMA; Time). It is multiplexed by (Division Multiple Access) control. At this time, the transmission unit on the optical fiber is generally called a burst. The bursts output to the optical fibers 5-1 to 5-N merge at the coupler 4-1, and reach the subscriber line interface 10-1 via the optical fiber 3-1.
In the reception process of the subscriber line interface 10-1, the upstream transmission frame in the PON section is terminated, the GEM frame is identified, and transferred to the MAC frame transfer control unit 20. The MAC frame transfer control unit 20 exchanges the received MAC frames and distributes them to the subscriber line interfaces 10-1 to 10-M or the intra-station / inter-station interfaces 30-1 to 30-L. The frame transferred to the subscriber line interfaces 10-1 to 10-M is processed in the PON section downlink transmission direction. The frames transferred to the intra-station / inter-station interfaces 30-1 to 30-L are converted into formats corresponding to the intra-station / inter-station transmission paths 6-1 to 6-L, and the intra-office / inter-station transmission paths 6-1 to 6-1. 6-L. The control unit 40 performs control necessary for the present embodiment, such as logical connection settings in the PON section and settings necessary for frame transfer. The setting of the logical connection in the PON section can be set for the ONTs 2-11 to 2-1N via the communication called OMCI shown in Non-Patent Document 4, for example. The control unit 40 is connected to the control terminal 8 via the control line 9, and various settings necessary for the operation of the apparatus are possible.

FIG. 20 is an explanatory diagram of the GEM frame / internal frame.
Here, the frame format among the subscriber line interfaces 10-1 to 10-M, the intra-station / inter-station interfaces 30-1 to 30-L, and the MAC frame transfer control unit 20 will be described with reference to FIG. deep. The frames on the in-device HW connecting the MAC frame transfer control unit 20 to the subscriber line interfaces 10-1 to 10-M and the intra-station / inter-station interfaces 30-1 to 30-L are additionally used only within the device. In-device frame 90 is used to exchange various information. The in-device frame 90 uses the area of the GEM frame header 71 of the GEM frame 70 to transfer the ID 91 in the transmitting device and the ID 92 in the receiving device. The MAC frame is mounted on the intra-device frame and the GEM frame. A method for mounting a MAC frame on a GEM frame is defined, for example, in Non-Patent Document 1, and each field of DA81, SA82, TYPE / LENGTH83, payload 84, and CRC85 corresponds to a MAC frame. The intra-device frame 90 uses the header area 71 of the GEM frame 70 carrying the MAC frame for intra-device transfer of the transmission device ID 91 and the reception device ID 92.

2. Station equipment OLT

(1) MAC Frame Transfer Control Unit FIG. 4 is a configuration diagram of the MAC frame transfer control unit 20 of the OLT 1. The MAC frame transfer control unit 20 includes a frame transfer table 201, a special frame transfer table 202, a frame transfer control unit 203, a frame buffer 204, intra-device frame transmission / reception units 205-1 to 205-2, 206-1 to 206-2, Intra-device interfaces 207-1 to 207-2, 208-1 to 208-2, and an intra-device bus 210 are provided. Each intra-device HW is connected to the subscriber line interfaces 10-1 to 10-M and intra-station / inter-station interfaces 30-1 to 30-L, and is configured to transmit and receive intra-device frames 90.
First, the processing of the in-device frame 90 transferred to the MAC frame transfer control unit 20 will be described. Here, the description will be made on the assumption that the MAC frame is transferred from the intra-station / inter-station interface 30-1 to the subscriber line interface 10-1. The intra-apparatus frame 90 transferred from the intra-station / inter-office interface 30-1 via the intra-apparatus HW is received by the intra-apparatus interface 208-1 and transferred to the intra-apparatus frame transmission / reception unit 206-1. The intra-device frame transmission / reception unit 206-1 temporarily holds the received intra-device frame 90, and adjusts the timing of the frame transfer processing performed by the frame transfer control unit 203. The frame transfer control unit 203 detects the arrival of the in-device frame 90 at the in-device frame transmission / reception unit 206-1 based on a change in the signal line 225-1, and the received in-device frame 90 is framed via the in-device bus. Transfer to buffer 204. Further, the MAC frame transfer control unit 203 refers to the frame transfer table 201 for the intra-device frames stored in the frame buffer 204 and identifies the transfer destination of the intra-device frame 90. At this time, the frame transfer control unit 203 selects whether to use the unicast connection in the PON section or the multicast connection according to the value of the ID 91 in the transmitting apparatus given to the frame in the apparatus. For example, if the in-device ID = 1 corresponding to the table value 1260-1 in FIG. 5 is assigned and the in-device frame 90 is transferred to the subscriber line interface 10-1, the GEM frame with Port ID = 101 is obtained. Installed. As a result, the MAC frame is transferred to the ONT # 1-1 2-11 via the unicast connection 901 in the PON section. Similarly, if it is intended to use the table value 1260-0 and ID in the apparatus is given, it is converted to Port ID = 100, and the ONT under the subscriber line interface 10-1 is converted by the multicast connection 900 in the PON section. The MAC frame is transferred to all.

  However, some protocols that use multicast or broadcast include subscriber addresses and the like, which may hesitate to use a multicast connection in the PON section. For such a MAC frame, it is necessary to perform transfer processing by determining the payload type of the MAC frame and the contents of the upper protocol in the payload. For this purpose, a transfer process using the special frame transfer table 202 is provided. The transfer processing using the special frame transfer table 202 described here is, for example, that a specific area in the MAC frame is specified as a filter condition area in advance, and if the specified condition is met, the frame transfer table 201 Instead, it is a process of designating a MAC frame transfer destination using the special frame transfer table 202. For example, the frame transfer control unit 203 can determine that the arrived in-device frame is a multicast / broadcast MAC frame but cannot use the multicast connection in the PON section as described above. In this case, the identification conditions of the multicast / broadcast MAC frame and the identification conditions of other necessary frames are designated, and for the MAC frame that matches the designated conditions, refer to the special frame forwarding table 202. The PON section unicast connection may be used to transfer the in-device frame 90.

As described above, the frame transfer control unit 203 refers to the frame transfer table 201 or the special frame transfer table 202, so that the transmission corresponding to the transfer destination subscriber line interface 10-1 and the output route of the MAC frame is performed. Search the device ID. Finally, the frame transfer control unit 203 reads the in-device frame to be transmitted, assigns the in-device ID 91, and transfers the frame to the in-device frame transmitting / receiving unit 207-1. The intra-device frame transmission / reception unit 207-1 transfers the intra-device frame to be transmitted to the subscriber line interface 10-1 via the intra-device HW.
As an example of using the special frame transfer table 202, there is a protocol such as DHCP described in Non-Patent Document 3 described above. In the DHCP protocol procedure, a subscriber's IP address is generally assigned using a broadcast of the MAC layer. If the DHCP frame is simply transferred using the multicast connection in the PON section, the frame used for assigning the IP address is transferred to all users sharing the PON section. When transferring the MAC frame used in such a protocol in the downstream direction of the PON section, the ONT to be transferred is limited based on the information registered in the special frame transfer table 202, and the unicast connection of the PON section is set. Can be used to transfer MAC frames.

Next, an operation example of the MAC frame transfer control unit 20 will be described with reference to FIGS.
FIG. 8 shows an example of a method for mounting the frame transfer table 201. This table shows the frame transfer information including the transfer route of the MAC frame for the destination MAC address area 2011 of the received frame, the subscriber line interfaces PON # 1 10-1 to PON # M 10-M, in-station / station Each of the inter-interface SNI # 1 30-1 to SNI # L 30-L can be registered in the destination registration areas 2012, 2013, 2014, and 2015.
FIG. 9 shows FIG. 8 in more detail. The destination registration areas 2012, 2013, 2014, and 2015 are configured so that IDs within a transmission device that are MAC frame transfer paths can be registered in a bitmap format. In FIG. 9, “1” is set in the bit 2012-1 for the ID in the transmission apparatus = 1, which indicates that the destination is registered. In addition, control flag areas 2012-7 and 2012-8 for controlling the transfer path of the MAC frame are provided. The first control flag area 2012-7 indicates that the multicast connection in the PON section is used, and when possible, the multicast / broadcast of the MAC frame is transferred using the multicast connection in the PON section (for example, 1 : Multicast, 0: Unicast). A second control flag area 2012-8 is a flag indicating that transfer of a frame input from the UNI to the UNI is prohibited. The second control flag area 2012-8 suppresses communication between subscribers unintended by the service provider, such as preventing the multicast / broadcast from the subscriber from being inadvertently transferred to other subscribers. (For example, 1: no transfer, 0: transfer). Unicasting is naturally included in the suppression of communication between unintended subscribers. Note that the control flag region can be appropriately provided for other controls as needed.
The details of the operation will be described using, for example, the table value 2010-1 in FIG. 9, and the corresponding destination MAC address (00: 00: aa: bb: cc: 01) is the subscriber line interface 10-1. This indicates that the transfer route designated by the transmission device internal ID = 1 is the destination. The first control flag 2012-7 is “0”, indicating that only the unicast connection is used in the PON section because the destination is a unicast connection. The second control flag is “1”, indicating that frames from other subscribers (UNI) are not transferred.

Hereinafter, as a specific example, the setting pattern and operation of the frame transfer table 203 will be described in detail. First, the unicast operation will be described with reference to FIGS.
FIG. 17 is an explanatory diagram showing an example of the setting state of the frame transfer table.
FIG. 17 shows that table values 2011-11, 2011-2, 2011-3, 2011-4, and 2011-5 having unicast destination MAC addresses are set in the frame transfer table 203. The table value 2011-1 shows a state in which the destination MAC address = 00: 00: aa: bb: cc: 01 is registered, and has the destination in the transmission apparatus ID = 1 of the subscriber line interface 10-1. This is the same setting as in FIG. The table value 2011-2 indicates that the destination MAC address (00: 00: aa: bb: cc: 02) is set to DI = 2 in the transmission apparatus of the subscriber line interface 10-1, and the table value 2011-4 indicates the destination MAC address. = 00: 00: aa: bb: cc: 04 is registered as the transfer route in the in-device ID = 4 of the subscriber line interface 10-1. The table value 2011-3 and the table value 2011-5 have a destination MAC address = 00: 00: aa: bb: cc: 03 and a destination MAC address = 00: 00: aa: bb: cc: 05. It shows that the transfer route is registered in the intra-station / inter-station interface 30-2. However, since the first control flag area is set to “1” in the table value 2011-1, for a MAC frame having a destination MAC address = 00: 00: aa: bb: cc: 01, Transfer between UNIs is prohibited.

FIG. 10 is an explanatory diagram of a unicast MAC frame transfer path. FIG. 11 is an explanatory diagram showing the setting effect (unicast) of the second control flag area. FIGS. 10 and 11 show MAC frame transfer paths when the frame transfer table 201 is registered as shown in FIG.
Reference numbers (1), (2), (3), (4), (5) attached to the MAC frame transfer paths 801, 802, 803, 804, 805, and 810 described in FIGS. Are the reference numbers (1), (2), (3), (4), (4) added to the table setting values 2011-1, 2011-2, 2011-3, 2011-4, 2011-5 in FIG. This corresponds to 5). For example, the MAC frame transfer paths 801 and 810 indicated by the number (1) in FIGS. 10 and 11 correspond to the reference number (1) in FIG. 17, and transfer determination is performed using the table value 2011-1. It is for supplementary explanation that is performed.
Regarding the reference number (1), in FIG. 10, the MAC frame transfer path 801 has a table value 2011-1 (destination MAC address) shown in FIG. 17 having a destination in the transmission apparatus ID = 1 of the subscriber line interface 10-1. = 00: 00: aa: bb: cc: 01). The frame having the destination MAC address = 00: 00: aa: bb: cc: 01 input from the intra-station / inter-station interface 30-1 is determined by the transfer destination determined by the value registered in the table value 2011-1. Inner ID = 1 is assigned and transferred to the subscriber line interface 10-1 as unicast in the PON section. Thereby, the MAC frame transfer path 801 is formed. The same applies to the MAC frame transfer paths 802, 803, 804, and 805 with respect to the reference numbers (2) to (5).
Table value 2011-2 (destination MAC address = 00: 00: aa: bb: cc: 02),
Table value 2011-3 (destination MAC address = 00: 00: aa: bb: cc: 03),
Table value 2011-4 (destination MAC address = 00: 00: aa: bb: cc: 04),
Table value 2011-5 (destination MAC address = 00: 00: aa: bb: cc: 05)
The frame transfer path for

  FIG. 11 is an example showing the setting effect (unicast) of the second control flag area 2012-8. The MAC frame transfer path 801 is the same as that described in FIG. The MAC frame transfer path 810 shows the operation when the MAC frame is transferred to the destination MAC address = 00: 00: aa: bb: cc: 01 from UNI # 2-2 7-22. In the MAC frame transfer path 810, the MAC frame is discarded by setting the second control flag area 2012-8 in the table value 2011-1. As described above, this explains the setting for suppressing transfer from UNI to UNI. The setting value “1” in the second control flag area 2012-8 means that the MAC frame transfer path 810 from UNI to UNI is inhibited, but the MAC frame transfer path 801 from SNI to UNI is permitted. Yes.

The above shows the unicast operation, but the multicast operation will also be described with reference to FIGS. 12, 13, 14, and 15. FIG. These reference numbers (6), (7), (8) attached to the MAC frame transfer paths 806, 807, 808 described in FIGS. 12 to 15 are the table setting values 2011-6, 2011 in FIG. -7, corresponding to reference numbers (6), (7), (8) added to 2011-13. For example, the MAC frame transfer path 806 indicated by the number (6) in FIG. 12 corresponds to the reference number (6) in FIG. 17, and the transfer determination is made using the table value 2011-6. This is for supplementary explanation.
In FIG. 17, table values 2011-6 and 2011-7 indicate that the destination MAC address = 01: 00: aa: bb: cc: 06, the destination MAC address = 01: 00: aa: bb: cc: 07 is the table value. The destination MAC address = ff: ff: ff: ff: ff: ff: ff is registered in the frame transfer table 203 by 2011-13. Here, the former two table values 2011-6 and 2011-7 indicate that multicast MAC addresses are registered, and the table value 2011-13 indicates that broadcast MAC addresses are registered. The multicast / broadcast destination is configured to transfer the MAC frame to all possible routes. For example, multicast is distributed to all destinations belonging to a specific group, while broadcast uses a special destination address (eg, ff: ff: ff: ff: ff: ff) and is transmitted to the network. It is delivered to all connected destinations.

  FIG. 12 shows the transfer path for the table value 2011-6 (destination MAC address = 01: 00: aa: bb: cc: 06) with respect to the reference number (6), from UNI # 2-3 7-23. The frame is transferred to all the routes via the MAC frame transfer route 806. This MAC frame transfer path 806 is set not to use multicast transfer in the PON section in the corresponding table setting value 2011-6. That is, the first control flag area is set to “0”, and the MAC frame transfer control unit 20 copies the MAC frame to all possible transfer paths. Intra-device IDs are assigned to the copied MAC frames and transferred to the corresponding subscriber line interfaces PON # 1 10-1 to PON # M 10-M. For example, an intra-device frame with intra-device ID = 1, 2, 3, 4 is transferred to the subscriber line interface PON # 1 10-1, and the subscriber line interface PON # 2 10-. For 2, the intra-device frame to which intra-device ID = 1, 2, 3 is assigned is transferred. For intra-station / inter-station interfaces SNI # 1 30-1 to SNI # L 30-L, copying and transfer of frames are performed in accordance with table setting values. Here, a point that requires attention is that the MAC bridge device must not transmit a MAC frame received from a specific interface from the same interface. In this description, this restriction is expressed by not transferring the MAC frame input from UNI # 2-3 7-23 in FIG. 12 only to the same UNI # 2-3 7-23. That is, even if there is a setting in the frame transfer table 201, this constraint is prioritized.

FIGS. 13 and 14 are explanatory diagrams (1) and (2) for the setting effect of the first control flag area. 13 and 14 show the transfer path when the first control flag area 2012-7 is set for the reference number (7).
FIG. 13 shows that the multicast frame input from SNI # 1 6-1 is transferred to another SNI # 2 6-2, and for all UNIs under PON # 1 3-1 and PON # 2 3-2. In the figure, a frame transfer path 807 for transferring using a multicast connection in the PON section is shown. That is, with respect to the reference number (7), the setting state for the purpose of actively using the multicast transfer in the PON section is shown. The multicast MAC frame (destination MAC address = 01: 00: 11: 22: 33: 07) input from the intra-station / inter-station interface 30-1 is sent to each subscriber line interface 10-1 to 10-M and the MAC frame. Are copied and transferred to the intra-station / inter-station interfaces 30-2 to 30-L excluding the interface that has received the signal. However, since the first control flag area is “1”, unlike the MAC frame transfer path 806 shown in FIG. 12, each of the UNIs 7-11 to 7-14, 7- The MAC frame is not copied in order to transfer the MAC frames to 21 to 7-23 individually. For example, for the subscriber line interface PON # 1 10-1, one in-device frame assigned with in-device ID = 0 is transferred. As a result, it is converted to Port ID = 100, and transferred to all of the subordinate UNIs 7-11 to 7-14 via the multicast connection 900 in the PON section (see FIGS. 5 and 6).

  FIG. 14 shows that the multicast frame input from UNI # 2-3 7-23 is transferred to SNI # 1 6-1 and SNI # 2 6-2, and for the UNI under PON # 1 3-1, A frame transfer path 807 for transferring using a PON section unicast connection is shown for a UNI under the PON # 2 3-2 that is transferred using a multicast connection in the PON section and the frame is input. . The frame transfer path 807 indicates a multicast MAC address transfer path corresponding to the setting of the table value 2011-7 (destination MAC address = 01: 00: aa: bb: cc: 07). This operation is for prohibiting the multicast MAC frame input from UNI # 2-3 7-23 from being transmitted from its own UNI. Since the first control flag area is “1”, the table setting value 2011-7 is a setting that uses multicast transmission in the PON section for the subscriber line interface PON # 2 10-2. is there. However, when multicast forwarding in the PON section is used, the MAC frame received at UNI # 2-3 7-23 is also forwarded to its own UNI, so priority is given to the operation for suppressing this. It is processing.

  Further, FIG. 15 shows the setting effect of the second control flag area 2012-8 for the multicast / broadcast frame. FIG. 15 relates to the table value 2011-13 with respect to the reference number (8). Multicast / broadcast frames input from UNI # 2-3 7-23 are designated as SNI # 1 6-1 and SNI # 2 6. A frame transfer path 808 for transferring only to -2. The frame transfer path 808 corresponds to the broadcast (destination MAC address = ff: ff: ff: ff: ff: ff: ff) table setting, but the setting of the frame transfer path is the same for multicast. This operation is a result of an operation for suppressing transfer from UNI to UNI due to the second control flag area being set to “1”.

Next, a pattern for transferring a MAC frame using the special frame transfer table 202 will be described. In this description, a function for assigning an IP address to a user called a DHCP server is provided in any of the intra-station / inter-station interfaces 30-1 to 30-L according to the DHCP procedure, and the subscriber transmission paths 7-11 to 7-11 are provided. Consider a case where an IP address is assigned to a user connected to 7-1N.
FIG. 23 shows an example of the setting state of the special frame transfer table 202. Further, the special frame transfer table 202 searches the transmission device ID of the transfer destination of the MAC frame using the destination MAC address area 2021 and the destination IP address area 2022 as indexes. Other areas have the same configuration as the frame transfer table 201. Here, since DHCP is assumed, it is assumed that a broadcast MAC frame is used. That is, in order to assign an IP address to a specific user, the normal DHCP server assigns an IP address to all ONTs connected to the PON section using the broadcast MAC address. For this reason, other users irrelevant to the IP address assignment can also receive the downlink broadcast MAC frame. In order to avoid this situation, the destination IP address area 2022 is also registered and compared with the IP address of the user in the broadcast MAC frame generated in the DHCP procedure. As a result, the transfer destination of the broadcast MAC frame transferred within the DHCP procedure is searched, and the MAC frame is transferred to specific subscriber transmission paths 7-11 to 7-1N. For example, the table value 2021-1 indicates that the broadcast MAC frame in which the destination MAC address = ff: ff: ff: ff: ff: ff: ff and the destination IP address = 192.168.0.1 is the ID in the transmission apparatus = 1 indicates that the data is transferred only to the subscriber line interface PON # 1 10-1. In this way, a MAC frame that is originally broadcast can be transferred to a specific user, and user information such as an IP address can be prevented from being transferred to an irrelevant user.

  By performing the MAC frame transfer process as described above, it is possible to prevent inadvertent transfer of frames from subscribers including multicast frames / broadcast frames to other subscribers. A multicast connection in the PON section can be used.

FIG. 16 is a diagram illustrating a specific operation sequence of the MAC frame transfer control unit 203.
10 to 17 are executed by the frame transfer control unit 203 of the MAC frame transfer processing unit 20 by referring to the frame transfer table 201 and the like of FIG. 17 (particularly, in step 3010 in FIG. 16). , 3014 etc.).
As described in FIG. 4 and the description thereof, the MAC frame transfer control unit 203 detects a change in the signal lines 215-1, 215-2, 225-1, and 225-2, thereby performing a frame arrival processing step 3001. To start. When the MAC frame transfer control unit 203 detects reception of the MAC frame, the MAC frame transfer control unit 203 executes a frame transfer step 3002 to transfer the arrived in-device frame 90 to the frame buffer 204. Whether the in-device frame 90 transferred to the frame buffer 204 is handled as a special frame by the MAC frame transfer control unit 203 by referring to the special frame transfer table 202 in the filter condition determination step 3003 is determined. Inspect the area. As a result of the filter condition determination step 3003, conditional branching by the special frame determination step 3004 is executed, and when it is determined that the frame is a special frame, the MAC frame transfer control unit 203 proceeds to processing by the special frame transfer table search step 3006.

If it is determined in the special frame determination step that the frame is a normal frame other than the special frame, the MAC frame transfer control unit 203 executes a frame header extraction step 3005 and reads a header including the MAC address. The MAC frame transfer control unit 203 shifts the process to the frame transfer table search step 3007 based on the extracted frame header, and whether or not the MAC address is registered in the frame transfer table 201 in the destination MAC address registration determination step 3008. Branch decision is performed. When the MAC address registration exists in the frame transfer table 201, the MAC frame transfer control unit 203 executes the registration data reference step 3010 to refer to the corresponding destination. On the other hand, if there is no MAC address registration in the frame transfer table 201, the MAC frame transfer control unit 203 further performs the determination in the unicast frame determination step 3009 to identify whether it is multicast or unicast from the MAC address or the like. Whether the frame is a unicast MAC frame or a multicast MAC frame is identified by a method such as searching a predetermined table. If it is determined as a unicast MAC frame as a result of the unicast frame determination step 3009, an unregistered unicast data reference step 3011 is executed to search for a frame transfer path at the time of unregistration. If the unicast frame determination step 3009 determines that the frame is a multicast MAC frame, the MAC frame transfer control unit 203 executes an unregistered multicast data reference step 3012 to search for a frame transfer path when not registered. These unregistered unicast data reference step 3011 and unregistered multicast data reference step 3012 can be executed by a method such as searching a predetermined table for identifying a transfer destination with respect to a MAC address, for example. .
If it is determined in the special frame determination step 3004 that the frame is a special frame, the MAC frame transfer control unit 203 branches to the special frame transfer table search step 3006 and refers to the special frame transfer table 202. The MAC frame transfer control unit 203 performs the process of the special frame transfer data reference step 3013 using the result of the special frame transfer table search step 3006 to determine the frame transfer path. With the above procedure, a table for determining a frame transfer path is searched.

  The MAC frame transfer control unit 203 uses the result of the table search to execute the process of the transfer destination acquisition step 3014, determines the transfer route to which the MAC frame is to be transferred, and performs the frame copy number calculation step 3015 following this. The number of MAC frames to be copied is obtained. The frame copy number determination step 3016 is a determination condition for repeatedly performing processing with the frame copy end determination step 3020. In the iterative process, the MAC frame transfer control unit 203 assigns the ID within the transmission apparatus in the frame transmission internal header generation step 3017, and in the frame transfer step 3018, the apparatus internal frame transfer processing unit 205-1, Intra-device frames are transferred to 205-2, 206-1 and 206-2. When the necessary number of frame transfers is completed, the MAC frame transfer control unit 203 ends the process according to the condition of the frame copy end determination step 3020. If the copy number of the frame is 0, the process branches to the frame discard step 3021 and the frame is discarded.

  In the operation example of the above flowchart, for example, with respect to the reference number (1) in FIG. 17, when the destination MAC address is 00: 00: aa: bb: cc: 01, the MAC frame transfer processing unit 20 determines the PON # 1 10-1 is determined as the transfer route, and the transmission device ID of the device frame is set to 1. The subscriber interface PON # 1 10-1 that has received this in-device frame refers to the downlink header conversion table 126 based on the in-device ID = 1 (see FIG. 5 described later), and searches for Port ID = 101. Then, the in-device frame is converted into a GEM frame.

(2) Subscriber line interface (PON)
FIG. 2 shows a configuration diagram of the subscriber line interfaces 10-1 to 10-M. The subscriber line interface 10 includes an optical transmission / reception unit 101, an in-device interface 102, a PON section signal control unit 103, an optical / electrical conversion 111, an upstream PON frame termination unit 112, an upstream GEM frame termination unit 113, an upstream frame conversion unit 114, Upstream GEM Port ID table 115, Upstream header conversion table 116, Downstream frame conversion unit 121, Downstream GEM frame generation unit 122, Downstream PON frame generation unit 123, Electrical / optical conversion 124, Downstream GEM Port ID table 125, Downstream header conversion table 126 and a control interface unit 186.

  The intra-device frame in the downlink transmission direction transferred by the MAC frame transfer control unit 20 is received by the intra-device interface 102 and transferred to the downlink frame conversion unit 121. Here, the frame transfer between the MAC frame transfer control unit 40 and the subscriber line interfaces 10-1 to 10-M and the intra-station / inter-station interfaces 30-1 to 30-M uses the intra-device frame as described above. I will do it. The downlink frame conversion unit 121 refers to the downlink header conversion table 126, rewrites the received header of the in-device frame 90, converts it to the GEM frame 70, which is a transmission unit of the PON section, and a downlink GEM frame generation unit 122. The downstream GEM frame generation unit 122 searches the GEMPort ID table 125 using the value of the Port ID field 73 in the GEM frame header 71 received from the header conversion unit 121 as an index. The GEMPort ID table 125 is a table for setting a connection in the PON section, and a GEMPort ID is registered. Here, the connection of the PON section is a logical connection unit of the PON section identified by the Port ID 73 in the GEM frame header 71. When there is a connection to which the GEM frame to be transmitted belongs in the GEMPort ID table 125, the downlink GEM frame generation unit 122 transfers the GEM frame to the downlink PON frame generation unit 123. The downlink PON frame generation unit 123 generates a downlink transmission frame for the PON interval based on information from the downlink GEM frame generation unit 122 and the PON interval signal control unit 103, and mounts the GEM frame in the downlink transmission frame for the PON interval. , And transfer to the electrical / optical conversion 124. The electrical / optical converter 124 converts an electrical signal into an optical signal for output to the transmission path 3 and outputs the optical signal to the transmission path 3 via the optical transceiver 101.

  In the upstream transmission direction, the upstream signal of the PON section input from the transmission path 3 is received via the optical transmission / reception unit 101 and transferred to the optical / electrical conversion 111. The optical / electrical converter 111 converts the received upstream signal into an electrical signal handled inside the apparatus, and transfers it to the upstream PON frame termination unit 112. The upstream PON frame termination unit 112 identifies a signal from each ONT, extracts a GEM frame multiplexed in the upstream transmission frame in the PON section, and transfers the GEM frame to the upstream GEM frame termination unit 113. The upstream GEM frame termination unit 113 searches the upstream GEMPort ID table 115 using the Port ID 73 in the header 71 of the received GEM frame as an index, and performs reception processing on the received GEM frame (for example, as described later) The information is acquired, etc.) and transferred to the upstream frame conversion unit 114. The upstream frame conversion unit 114 searches the upstream header conversion table 116 using the Port ID 73 in the transferred GEM frame header 71 as an index, and uses the GEM frame 70 as the in-device frame 90 based on the information registered in the table. And transferred to the in-device interface 102. The in-device interface 102 transfers the received frame to the MAC frame transfer control unit 20 via the in-device HW.

FIG. 5 is an explanatory diagram of the uplink / downlink header conversion table. FIG. 6 is an explanatory diagram of an up / down GEM Port table (OLT). Here, the configuration of the downlink header conversion table 126, the downlink GEM Port table 125, the uplink header conversion table 115, and the uplink GEM Port table 116 will be described with reference to FIGS.
First, the downlink transmission direction will be described. The downlink header conversion table 126 is a table for searching a Port ID using the value of the ID area 1261 in the downlink device as an index. The corresponding Port ID is searched using the intra-device ID 91 of the intra-device frame 90 received from the intra-device HW as an index, the format of the intra-device frame is converted to the GEM frame 70, and the value of the Port ID 73 in the GEM frame header 71 Is used to mount the searched Port ID. For example, in the value of the table shown in 1260-1, the intra-device frame with ID in the transmitting device = 1 is converted to Port ID = 101. The downlink GEM Port table 125 is a table for searching connection information in the PON section using the Port ID area 1251 as an index. The connection information in the PON section includes a valid flag 1252 for indicating a connection setting state, a connection destination ONT 1253, and the like. The downlink GEM frame generation unit 122 extracts a Port ID value from the GEM frame transferred from the downlink frame conversion unit 121, searches the downlink GEM Port table 125, and generates a GEM frame to be mounted on the downlink transmission frame in the PON section. To do. For example, the table value 1250-1 in FIG. 6 indicates that Port ID = 101 is transferred to the destination ONT = 1. The table value of 1250-0 indicates that Port ID = 100 is the destination ONT = Multi, that is, a multicast connection is set to a plurality of ONTs. The above is the description regarding the downlink transmission direction.

  Subsequently, the upward direction will be described. The upstream GEM Port table 115 is a table for searching connection information in the PON section using the value of the Port ID area 1151 as an index. The connection information is the same as that in the downlink direction, and includes a valid flag 1152 indicating a connection setting state, a connection source ONT 1153, and the like. The upstream GEM frame termination unit 113 searches the valid flag 115 and the connection source ONT 1153 using the Port ID 73 of the received GEM frame 71 as an index, and performs frame termination processing. The set value of the table is the same as that of the downlink GEM Port table 125. However, in the uplink direction, for example, Port ID = 100 corresponding to the multicast connection in the downlink transmission direction is invalid as the table value 1150-0. The upstream header conversion table 116 is a table for searching the ID 1162 in the receiving apparatus using the value of the Port ID area 1161 as an index. The upstream frame conversion unit 114 searches the upstream header conversion table 116 using the Port ID of the received GEM frame as an index, obtains the corresponding reception device ID, and embeds it in the header part of the device frame 90.

3. Terminal device ONT

FIG. 3 shows a configuration diagram of the optical passive network termination unit 50 of ONT # 1-1 to ONT # 1-N. The optical passive network termination unit 50 includes an in-device interface 501, an optical transmission / reception unit 502, a PON section access control unit 503, an upstream GEM frame generation unit 511, an upstream data buffer 512, an upstream PON frame generation unit 513, an electrical / optical conversion 514, An upstream GEMPort ID table 515, an optical / electrical conversion 521, a downstream PON frame termination unit 522, a downstream GEM frame termination unit 524, and a downstream GEMPort ID table 525 are provided.
In ONT, a signal in the downstream direction of the PON section input from the transmission path 5 is received by the optical transmission / reception unit 502 and transferred to the optical / electrical conversion 521. In the optical / electrical conversion 521, the received downstream signal is converted into an electrical signal in the apparatus and transferred to the downstream PON frame termination unit 522. The downstream PON frame termination unit 522 terminates the downstream transmission frame in the PON section, extracts the access control information in the upstream direction of the PON section, transfers the access control information to the PON section access condition control unit 503, and transmits GEM from the downstream transmission frame in the PON section. The frame 70 is extracted and transferred to the downstream GEM frame termination unit 524. The downlink GEM frame termination unit 254 refers to the Port ID 73 in the header of the received GEM frame 70 and searches the downlink GEMPort ID table 525 using this as an index. As a result of the search, only the frame having the registered Port ID is determined as the GEM frame addressed to itself, and transferred to the in-device interface 501. The in-device interface 501 transfers the transferred GEM frame to the UNI processing units 2-11 to 2-1N via the in-device HW. The UNI processing units 2-11 to 2-1N finally convert the signal format to be provided to the user and output it as a MAC frame.

  The MAC frame input from each user is subjected to reception processing in the UNI processing units 2-11 to 2-1N, associated with the Port ID to be used, and transferred to the uplink GEM frame generation unit 511. The frame input to the uplink GEM frame generation unit 511 can take an arbitrary format, but a format including a Port ID to which the association is performed is assumed. The upstream GEM frame generation unit 511 extracts the Port ID from the transferred frame, and searches the upstream GEMPort ID table 515 using this as an index. Based on the information obtained by the search of the upstream GEMPort ID search table 515, a GEM frame is generated and transferred to the upstream data buffer 512. The upstream data buffer 512 temporarily holds the GEM frame and transfers the GEM frame in accordance with the operation timing of the upstream PON frame generation unit 513. The upstream PON frame generation unit 513 generates an upstream transmission frame of the PON section according to the transmission timing generated by the PON section access case control unit 503, stores the transferred GEM frame, and transfers the frame to the electrical / optical conversion 514. . The electrical / optical conversion 514 also operates at a timing designated by the PON section access right control unit 503, and outputs an upstream transmission frame of the PON section onto the optical transmission line 5 via the optical transmission / reception unit 502.

FIG. 7 is an explanatory diagram of the up / down GEM Port table (ONT).
Next, the downstream GEM Port table 525 and the upstream GEM Port table 515 will be described with reference to FIG. The downstream GEM Port table 525 is a table for extracting a GEM frame addressed to itself in the ONT, and is searched using the Port ID 5251 as an index. The downstream GEM Port table 525 includes an effective display area (effective flag) 5252 and another setting information area (other setting) 5253 in order to indicate the connection setting state of the PON section. For example, in the downstream GEM Port table 525, the table value of the data 5250-1 means that the Port ID = 101 is processed as the self address. If the valid display area 5252 is set to invalid, the downstream GEM frame terminating unit 524 discards the corresponding GEM frame even if it is received. If the valid display area 5252 is set to valid, the downlink GEM frame terminating unit 524 carry out.
The upstream GEM Port table 515 is a table for obtaining the connection setting state of the PON section using the Port ID area 5151 as an index. The upstream GEM frame generation unit 511 extracts the Port ID from the frame transferred from the in-device HW, searches the upstream GEM Port table 515, and displays the valid display area (valid flag) 5152 and other setting information areas (other settings). Corresponding information such as 5153 is obtained and a GEM frame is generated.
As described above, the logical connection of the PON section identified by the Port ID in the GEM frame is set.

FIG. 18 is an explanatory diagram for connection setting (unicast connection) in the PON section. FIG. 19 is an explanatory diagram for connection setting (multicast connection) in the PON section. The connection of the PON section as a specific setting example will be described with reference to FIGS.
FIG. 18 shows a unicast connection 901 with Port ID = 101 between the subscriber line interface 10-1 and the ONT # 1-1 2-11, and a unicast connection 902 with Port ID = 102 between the subscriber line interface 10-1 and the subscriber line interface 10-1. Similarly, the unicast connections 903 and 904 with Port ID = 103, 104 are connected to the subscriber line interface 10-1 and the ONT # 1-3 2-13 to the ONT # 1-2 2-12. -1 and ONT # 1-4 2-14, respectively. Using these unicast connections 901 to 904, bidirectional transmission between the OLT and the ONT is possible. For example, with reference number (1), the MAC frame input from SNI # 1 6-1 is transferred to the frame transfer path 801 by the MAC frame transfer control unit 20, and UNI # 1 7− is transmitted via the unicast connection 901. 11 is transferred. With reference number (2), the frame transmission path 802 is further connected to the unicast connection 903 after the MAC frame input from UNI # 3 7-13 is transferred to the MAC frame transfer control unit 20 and then further to the unicast connection 903. It shows that the data is transferred to UNU # 2 7-12 via the cast connection 902. In FIG. 18, the unicast connections 901 and 902 are used for downlink transfer, and the unicast connection 903 is used for uplink transfer. As described above, the connections 901 to 904 in FIG. 18 can perform forward and backward bidirectional frame transfer.

FIG. 19 shows an example of setting a multicast connection that can be used only in the downlink transmission direction of the PON section. FIG. 19 shows a state in which a connection 900 with Port ID = 100 is set between the subscriber line interface 10-1 and each of the ONTs # 1 to # 4 2-11 to 2-14. With the reference number (3), the MAC frame input from the SNI # 1 6-1 can be transferred to the connected ONTs # 1 to # 4 via the transfer path 808. However, frame transmission in the upstream transmission direction is impossible for the multicast connection 900.
In this description, it should be noted that if the MAC frame transfer control unit 20 can recognize the connection in the PON section, the MAC frame transfer using the multicast connection 900 as shown in FIG. As shown, MAC frame transfer using unicast connections 901 to 904 is also possible.

  Here, the uplink / downlink GEM PORT table of FIG. 6 is set to the subscriber line interface 10-1 of the OLT 1 for realizing the unicast connections 901 to 904 and the multicast connection 900 shown in FIGS. The state is supplemented in that the upstream / downstream GEM PORT table in FIG. 7 indicates the setting state for the ONT # 1-1 2-11. For example, the table values 1150-1 and 1250-1 in FIG. 6 indicate the settings of the subscriber line interface 10-1 corresponding to the unicast connection 901, and the table values 5150-1 and 5250-1 in FIG. The settings for ONT # 1-1 2-11 are shown. The multicast connection 900 is also represented by table values 1150-0 and 1250-0 in FIG. 6 and table values 5150-0 and 5250-0 in FIG. That is, in this setting, the MAC frame transfer control unit 20 can transfer the MAC frame using the unicast connection 901 and the multicast connection 900 to the ONT # 1-1 2-11.

The present invention can be applied to a PON type network other than the PON shown in FIG. 1 and various PON type networks other than the optical network.
Further, as an example, a GEM frame, a MAC frame, an in-device frame, and the like have been described as examples. However, the present invention can be applied to other appropriate frames.

PON system connection configuration diagram. The block diagram of a subscriber line interface. The block diagram of an optical passive network termination | terminus part. The block diagram of a MAC frame transfer control part. Explanatory drawing of an up / down header conversion table. Explanatory drawing of an up / down GEM Port table (OLT). Explanatory drawing of an up / down GEM Port table (ONT). Explanatory drawing of the structural example of a frame transfer table. Explanatory drawing of the detail of the structural example of a frame transfer table. Explanatory drawing of a unicast MAC frame transfer path | route. Explanatory drawing about the setting effect (unicast) of a 2nd control flag area | region. Explanatory drawing of a multicast MAC frame transfer path | route. Explanatory drawing about the setting effect (1) of a 1st control flag area | region. Explanatory drawing about the setting effect (2) of a 1st control flag area | region. Explanatory drawing about the setting effect (multicast) of the 1st / 2nd control flag area | region. The operation sequence of the MAC frame transfer control unit. Explanatory drawing about an example of the setting state of a frame transfer table. Explanatory drawing about the connection setting (unicast connection) of a PON area. Explanatory drawing about the connection setting (multicast connection) of a PON area. FIG. 3 is an explanatory diagram of a GEM frame / internal frame. The block diagram of a GEM frame. The block diagram of a GTC frame. Explanatory drawing of an example of the setting state of a special frame transfer table.

Explanation of symbols

1 ... OLT, 2-11 to 2-1N ... ONT, 3-1 to 3-M, 5-11 to 5-1N ... optical transmission line,
4-1 ... optical splitter, 6-1 to 6-L ... intra-station / inter-station transmission path,
7-11 to 7-1N: subscriber transmission path, 10-1 to 10-M: subscriber line interface,
20 ... MAC frame transfer processing unit, 30-1 to 30-L ... Intra-station / inter-station interface,
40 ... control unit, 50-11 to 50-1N ... optical passive network termination unit,
60-11 to 60-1N ... UNI processing unit,

70 ... GEM frame, 71 ... GEM frame header,
81 ... DA (destination MAC address), 82 ... SA (source MAC address), 84 ... payload,
85 ... CRC,
90 ... Intra-device frame, 91 ... Transmitting device ID, 92 ... Receiving device ID,
93 ... unused area,
95-1 ... PCBd, 95-2 ... Payload, 97-1 ... PCBu, 97-2 ... PLOAMu, 97-3 ... PLSu,
97-4 ... DBRu, 97-5 ... Payload,
115: Upstream GEM Port ID table, 116: Upstream header conversion table,
125 ... Downstream GEM Port ID table, 126 ... Upstream header conversion table,
201: Frame transfer table, 202: Special frame transfer table,
203 ... Frame transfer control unit, 204 ... Frame buffer, 210 ... In-device bus,
205-1, 205-2, 206-1, 206-2 ... Intra-device frame transmission / reception unit,
207-1, 207-2, 208-1, 208-2 ... interface in the device,
515: Upstream GEM Port ID table, 525: Downstream GEM Port ID table,
801 to 805 ... Unicast MAC frame transfer path,
806: Multicast MAC frame transfer path (normal)
807 ... Multicast MAC frame transfer path (using the first control flag),
808 ... Multicast MAC frame transfer path (using second control flag),
810 ... Unicast MAC frame transfer path (using second control flag),
900 ... PON section multicast connection,
901-904 ... unicast connection in PON section,
2011 ... Destination MAC address registration area, 2012-2015 ... Transmission device ID registration area,
2012-1-2012-6 ... ID flag area in transmitting device,
2012-7: first control flag area, 2012-8: second control flag area,
2021 ... Destination MAC address registration area, 2022 ... Destination IP address registration area,
2013, 2014 ... Transmission device ID registration area

Claims (10)

A station apparatus, a plurality of terminal apparatuses, and a coupler that joins and diverts a plurality of optical transmission paths from each of the terminal apparatuses and one optical transmission path from the station apparatus, from the station apparatus to the terminal A downlink transmission frame to the apparatus is transmitted from the station apparatus by a single station apparatus to a plurality of terminal apparatuses with a one-to-N logical connection in the terminal apparatus direction (N is 1 or more), and from the terminal apparatus. The upstream transmission frame to the station apparatus is a passive transmission in which signals from each terminal apparatus are multiplexed by time division multiple access through a one-to-one logical bidirectional connection by a single terminal apparatus to a single station apparatus. The station apparatus in an optical network (PON),
Connected to the optical transmission path on the terminal side, terminates the upstream transmission frame, converts the terminal device from a GEM frame, which is a transmission unit in the PON section with the station device, to an intra-device frame, and A subscriber line interface for converting a transmission frame from an in-device frame to a GEM frame;
An intra-station / inter-station interface connected to the intra-station / inter-station transmission path;
A MAC frame transfer processing unit that is connected to the subscriber line interface and the intra-station / inter-station interface and transfers intra-device frames;
For the destination MAC address of the received frame, an intra-device ID that is a transfer path of the MAC frame is registered for each of the subscriber line interface and the intra-station / inter-station interface, and the one-to-N logic A first control flag region indicating that a typical one-way connection can be used for frame transfer, and a second control flag region indicating that frame transfer from the terminal device to another terminal device is prohibited. The frame forwarding table including:
With
The MAC frame transfer processing unit
Upon receiving a MAC frame mounted in an intra-device frame from the subscriber line interface or the intra-station / inter-station interface, a MAC address is extracted from the MAC frame,
The frame transfer table is searched based on the extracted MAC address, and the subscriber line interface and the in-device ID serving as a transfer route to which the MAC frame is to be transferred and / or the intra-station / inter-station interface and the Find the device ID,
If the first control flag area is set in the retrieved data of the frame transfer table, a 1 to N logical connection is used, and if the second control flag area is set, the terminal On condition that frame transfer from the device to the other terminal device is prohibited, the necessary number of MAC frames are copied in accordance with the obtained number of in-device IDs, and the in-device ID is assigned with each in-device ID. Forming and transferring the intra-device frame toward the subscriber line interface and / or the intra-station / inter-station interface which is a transfer route,
The station apparatus in a passive optical network (PON). For the down direction,
For a MAC frame mounted in an intra-device frame input from the intra-station / inter-station interface from the intra-station / inter-station transmission path, the MAC frame transfer processing unit determines a MAC frame transfer destination interface, and the MAC frame Transfer the frame to the subscriber line interface or other intra / inter-station interface;
The subscriber line interface, the MAC frame transferred, mounted on GEM frame multiplexes the downlink transmission frame, broadcast to feed heat to either the plurality of terminals via said optical transmission line the station device in a passive optical network (PON) according to claim 1, wherein to Rukoto.
With respect to the destination MAC address and the destination IP address, an intra-device ID serving as a MAC frame transfer path is registered for each of the subscriber line interface and the intra-station / inter-station interface, and the 1: N A first control flag area indicating that a logical one-way connection can be used for frame transfer, and a second control flag area indicating that frame transfer from the terminal device to another terminal device is prohibited. And a special frame forwarding table including
When the MAC frame transfer processing unit determines that the MAC frame mounted on the received in-device frame is a special frame based on predetermined data, the special MAC address area and the destination IP address area are used as indexes to determine the special frame. The station apparatus in the passive optical network (PON) according to claim 1 or 2, wherein a frame transfer table is searched to determine a transfer path.   When the MAC address extracted in the frame transfer table is unregistered, the MAC frame transfer processing unit refers to a table in which a unicast or multicast transfer destination is predetermined with respect to the MAC address, The station apparatus in the passive optical network (PON) according to any one of claims 1 to 3, wherein a frame transfer path when not registered is searched.   When the first control flag area is set to '0', the MAC frame transfer processing unit performs copying of the number of MAC frames for all the searched transfer paths, and for the copied MAC frame The passive optical network (PON) according to any one of claims 1 to 4, wherein an intra-apparatus ID is assigned, and a MAC frame is transferred to the corresponding subscriber line interface and / or the intra-station / inter-station interface. ) In the station device.   When the first control flag area is set as '1', the MAC frame transfer processing unit does not copy the MAC frame to transfer the MAC frame individually for each terminal device, and the subscriber By transferring one intra-device frame with a specific intra-device ID indicating multicast to the line interface, it is possible to transfer to all the searched subscriber line interfaces via the multicast connection in the PON section. The said station apparatus in the passive optical network (PON) in any one of Claim 1 thru | or 5 characterized by the above-mentioned.   When the extracted MAC address is a broadcast destination MAC address and the second control flag area for the MAC address corresponding to the frame transfer table is set to '1', the MAC frame transfer processing unit The station apparatus in the passive optical network (PON) according to any one of claims 1 to 6, wherein transfer from the terminal apparatus to another terminal apparatus is suppressed.   The passive optical network (PON) according to any one of claims 1 to 7, wherein the MAC frame transfer processing unit branches to frame discard and discards the frame when the copy number of the frame is zero. ) In the station device. The subscriber line interface is:
For the down direction,
For the intra-device frame in the downlink transmission direction transferred by the MAC frame transfer processing unit, the port ID that is the connection identification number of the PON section between the terminal device and the station device is stored for the intra-device ID. By referring to the downlink header conversion table, the port ID is obtained based on the in-device ID, the header of the received in-device frame is rewritten and converted into a GEM frame,
Referring to the downstream GEM port ID table storing the connection information / setting state for the port ID, the connection information / setting state of the PON section is searched based on the port ID in the header of the GEM frame, and the connection information / Generate a downlink transmission frame in the PON section based on the setting state, and output to the terminal device,
on the other hand,
For the upstream transmission direction,
The received GEM frame is extracted, and based on the port ID in the header of the received GEM frame, the connection information / setting is stored with reference to the upstream GEM port ID table storing the connection information / setting state for the port ID. Search the status, perform the receiving process for the received GEM frame based on the connection information / setting status,
Based on the port ID in the header of the GEM frame, the upstream header conversion table in which the in-device ID is stored for the port ID is searched, the in-device ID is obtained from the port ID, and the GEM frame is converted into the in-device frame. The station apparatus in the passive optical network (PON) according to claim 1, wherein the station apparatus transfers the packet to the MAC frame transfer processing unit.   The in-device frame uses the GEM frame header area of the GEM frame after converting it into information including the ID in the transmitting device and the ID in the receiving device. The station apparatus in a passive optical network (PON).

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