JP3299209B2 - Alarm prohibition information transfer method in high-speed digital leased line service, high-speed digital leased line service system, and SDH system transmission apparatus used therefor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for transferring alarm-prohibited information in a high-speed digital leased line service, a high-speed digital leased line service system, and an SDH system transmission apparatus used therewith. A method of transferring alarm prohibition information in a high-speed digital leased line service in which a subscriber line section is extended to perform transmission by the SDH method on a high-speed digital leased line composed of a subscriber line (LI point) section having a speed of 6.312 Mbps; The present invention relates to a high-speed digital leased line service system and an SDH system transmission device used for the system.

[0002]

2. Description of the Related Art An international standard synchronous digital hierarchy (SDH: Synchronous Digital Hierarcy) created by the International Telecommunication Union Telecommunication Standardization Sector (ITU-T).
In the multiplexing hierarchy of the system, as a data transmission unit, there is a VC (virtual container) -11 in 1.5 Mbps unit and a VC-21 in 6.3 Mbps unit. On the other hand, there is known a high-speed digital leased line service (I interface) composed of a section in a user's house and a section of a subscriber line (LI point).

FIG. 7 is a block diagram showing an example of the above-mentioned high-speed digital leased line service (I interface). As shown in the figure, in a high-speed digital leased line service (I interface) including a user premises section 1 having a service speed of 1.544 Mbps and a subscriber line section (LI point) 2 having a service rate of 6.312 Mbps, a terminal 3 is provided. An unnecessary alarm (REC alarm) is generated in the terminal device 5 connected to the subscriber line in distinction from the failure of the subscriber line when the power of the in-house device (DSU) 4 for transmitting data to the subscriber line is turned off. The RINH signal, which is the alarm prohibition information, is transmitted from the DSU 4 to the terminal device 5 for a certain period of time until the power is turned off. The RINH signal is allocated in 6M frame bits.

[0004] Here, as shown in FIG. 8, a case where the subscriber lines 2 are relayed by the SDH transmission devices 7 and 8 (a case where the subscriber line (LI point) is extended by the SDH transmission devices 7 and 8). ), Since the actual data amount is 1.5 Mbps, VC
Rather than transmitting on a -21 path transparently, the 6M frame transmitted at 6.312 Mbps is temporarily terminated by the SDH transmission device 7 and then transmitted to the 1.5M
The data of the unit path is separated, and the SDH transmission devices 7 and 8 are separated.
1.5-11 Mbyte multiplexed VC-11
It is more economical to transmit at 6.312 Mbps from the SDH transmission device 8 to the terminal device 5 after transmitting the data through the path, because the line use efficiency is good.

[0005]

However, the SDH transmission devices 7 and 8 shown in FIG.
As shown in FIG. 9, when the power of the DSU 4 is turned off, a RINH signal is allocated from the DSU 4 to the terminal device 5 in the 6M frame bits in the high-speed digital leased line service (I interface) with the extension of the point). And the SDH transmission device 7 detects this.
Since 6M frame bits cannot be transmitted through the 1.5M byte multiplexed relay transmission line 9, the SDH transmission device 7
The RINH signal is not transferred to the DH system transmission device 8, so that the terminal device 5 cannot detect the RINH signal.

[0006] In this case, the SDH transmission device 8 again
To send an M frame to the terminal equipment 5, the terminal equipment 5
Does not generate a REC alarm in units of 6M frames,
1.5 that is transmitted transparently from the SU 4 to the terminal device 5
The REC alarm 10 is generated for each M path.

Therefore, conventionally, the above-described 1 ..
In order to simply prevent the occurrence of the REC alarm 10 in units of 5M path, if the SDH transmission device 7 detects RINH, it generates a 1.5M path multi-frame and transfers it to the terminal device 5 by itself. This prevents the terminal station device 5 from continuously generating a REC alarm while the DSU 4 is turned off. However, in this case, DSU4
When the power supply is turned on / off, the terminal device 5 generates an instantaneous REC alarm in units of 1.5 M paths.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and it is an object of the present invention to provide an alarm prohibition in a high-speed digital leased line service capable of improving the line use efficiency between SDH transmission apparatuses and preventing unnecessary alarms from occurring. An object of the present invention is to provide an information transfer method, a high-speed digital leased line service system, and an SDH system transmission device used for the method.

[0009]

In order to achieve the above object, a method according to the present invention is provided, wherein a user's premises section having a first service speed including a home device and a first service speed including a terminal device are provided. between the second service rate of the subscriber line section, as well as extending the subscriber line section by connecting a plurality of SDH system transmission apparatus cascade, a plurality of SDH system transmission apparatus
During a VC11 path faster than the second service speed
In high speed digital leased line service for transmitting, home
Device consists of data, status and frame bits
To the terminal equipment at the second service rate in frame units
Output and when the power of the home device itself is turned off
To prevent unnecessary alarms from being generated by the terminal equipment.
RINH signal is pre-assigned in the frame bits
And output it as a frame by inserting
Of multiple SDH transmission devices,
The SDH transmission device on the connection side outputs the
When a frame of the second service rate is input,
And the RINH signal is output during that frame.
Detecting whether it is included in the frame
When the RINH signal is not included in the frame
Valid data and valid status from data and status
Modules that are multiplexed after separating only the
A SDH-based transmission device to generate a terminal
Step for relay transmission to the SDH transmission device on the device connection side
And when the frame contains a RINH signal
From the data and status in the frame,
After separating the valid status, multiplexing and the RINH signal
Newly generated warning prohibition information based on valid status
Transmitted on one VC path assigned to the spare bits of
Generate a transmission module to generate multiple SDH transmission devices
Relay transmission to the SDH transmission equipment on the terminal equipment connection side
Out of a plurality of SDH transmission devices.
The SDH transmission equipment on the terminal equipment connection side is connected to the home equipment.
Module input from the SDH transmission device on the side
For separating valid data and valid status from data
Alarm information is included in the spare bit in the transmission module.
Detecting whether or not the alarm has been detected, and alarm prohibition information
If not included, contains separate valid data
Status and frame with multiple data and valid status
A first frame of a second service rate comprising
Generates an alarm and transfers it to the terminal equipment, and includes alarm prohibition information.
Data with separate valid data
Pre-assigned status, including active status
Frame bits with RINH signal inserted in bits
Generating a second service rate frame comprising
Transferring to a device.

In order to achieve the above object, the system of the present invention provides a first service rate of 1.54 including an in-home device.
In a high-speed digital leased line service system having a 4 Mbps user home section and a second service rate 6.312 Mbps subscriber line section including a terminal station apparatus, when the power of the home apparatus is turned off, the terminal station apparatus uses RINH signal for unnecessary alarm is prevented occurs, the frame
6.312 Mbps inserted into the pre-allocated bits of the bits and transmitted from the home device to the terminal device
Receiving means for receiving a first frame consisting of data, status and frame bits, and a first receiving means
The RINH signal from the first frame received by
First detecting means for detecting and receiving by the first receiving means
Valid data in the data from the first frame
Status is separated from the effective status by the 1.5M path unit.
After multiplexing, the R detected by the first detecting means
Validates the alarm prohibition information generated based on the INH signal.
The module which has the spare bit of the task is generated and VC-
A first SDH system transmission apparatus that outputs the 11 path, VC
Second receiving means for receiving the module transmitted from the first SDH transmission device via the -11 path ;
Valid data and data received in the module received by the receiving means.
And valid status are separated and the alarm in the spare bit
Separation / detection means for detecting prohibited information, and separation / detection means
When the alarm prohibition information is detected by the
, A status with an active status,
The RINH signal generated based on the alarm prohibition information is
The frame bits inserted into the assigned bits are
And a second SDH transmission apparatus having a frame generation means for generating a multiplexed second frame of 6.312 Mbps and transmitting the generated second frame to the terminal station apparatus.

In the above-mentioned method and system of the present invention, when extending the subscriber line section of the second service rate of 6.312 Mbps of the high-speed digital leased line service of the first service rate of 1.544 Mbps, the frame of the second service rate is used. Is terminated and passed through a 1.5M path to generate a 1.5M path multi-frame having alarm prohibition information, and a synchronous transmission module that multiplexes the multi-frame to data separated from the first frame to a plurality of VCs. -11 path. Also, at this time, since the multi-frame having the alarm prohibition information is generated in synchronization with the signal from the in-home device, the multi-frame timing is always synchronized between the in-home device and the SDH system transmission device, and when the RINH is detected. Can generate and transmit a 1.5M path multi-frame having alarm prohibition information synchronized therewith.

In order to achieve the above object, a user's premises section having a service speed of 1.544 Mbps including a home device and a service speed of 6.312 Mbps including a terminal device are provided.
Between the ps subscriber line section, among the plurality of SDH system transmission apparatus to extend the connected subscriber line section in cascade, a SDH system transmission apparatus connection side of the in-home apparatus, home interior
The location is a file consisting of data, status, and frame bits.
The terminal equipment at a service rate of 6.312 Mbps
And the home device itself is turned off.
To prevent unnecessary alarms from being generated at the terminal equipment.
Signal is pre-assigned in the frame bits
Output the frame inserted in the
6.312 Mbps from the home device
And the end portion of frame synchronization and terminates the frame to be sent to the direction, from the end frame at the end a detection unit for detecting a RINH signal, of 1.5 M units pass from the end frame at the end A separating unit for separating data and status, a synchronizing unit for synchronizing with a frame based on the status separated by the separating unit, and a RINH by a detecting unit
At the time of signal detection, a first generation unit that generates a status multi-frame of a 1.5M unit path in which alarm prohibition information is inserted into pre-assigned bits in synchronization with synchronization timing from a synchronization unit, and a detection unit RINH signal is detected
A switching circuit that selects the status separated by the separation unit at the normal time when the status is not output, and a status multiframe from the first generation unit when the RINH signal is detected by the detection unit, and a status or a status selected by the switching circuit. and data from the status multiframe and the separation unit into a VC-11 path after multiplexing, or row inverse transform to separate the data and status for a plurality of VC-11 path signals
For a multiplexing unit and a plurality of VC-11 paths from the multiplexing unit, these are multiplexed and a signal of 155.52 Mbps is transmitted, and for a signal of 155.52 Mbps input from the outside, a plurality of signals are transmitted. And a second generation unit that multiplexes the data and status separated by the multiplexing unit to generate and transmit a 6.312 Mbps frame.

[0013] The SDH transmission apparatus of the present invention can realize the above-described method for transferring alarm-inhibited information and the high-speed digital leased line service system in the high-speed digital leased line service according to the present invention.

[0014]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing one embodiment of a high-speed digital leased line service system according to the present invention. In the figure, the same components as those in FIG.
The description is omitted. In FIG. 1, the subscriber line section 2 between the DSU 4 and the terminal equipment 5 has a 1.5 Mbyte multiplex (V
SD connected via the relay transmission line 13 of the C-11 path)
It is extended by the H system transmission devices 11 and 12.

When the DSU 4 is turned off, the DSU 4 allocates a RINH signal to a frame transmitted at 6.312 Mbps, that is, a 6M frame, and performs SDH transmission.
To the system transmission device 11. FIG. 2 shows a configuration diagram of an example of the 6M frame. In the figure, a 6M frame composed of 789 bits (125 μs) is composed of 24 time slots TS1 to TS24 each having 4 bits, a status ST of 16 bits, and a frame bit F of 5 bits.

The RINH signal is assigned to one of the frame bits F in units of four multiframes. C is a CRC code, D is a data link, BE
RR indicates the backward of the error signal. The 16-bit status ST is composed of four bits S1 to S4, and all four bits of S1 to S4 are 1.5 bits.
An M unit path (ST multi-frame) is configured.

Referring back to FIG. 1, when the SDH transmission apparatus 11 detects the RINH signal, the SDH transmission apparatus 11 operates as follows.
A multi-frame of 5M path is generated, and the SDH is generated via the relay transmission line 13 of 1.5M byte multiplexing (VC-11 path).
To the system transmission device 12. SDH transmission equipment 12
Detects this 1.5M path multi-frame,
It is converted into a 6M frame and transferred to the terminal device 5.

If the SDH transmission apparatus detects the RINH, the REC is generated during the power-off of the DSU 4 simply by generating a multi-frame of 1.5M path and transferring it to the terminal station 5 by itself. Although it can be prevented from continuing to occur, as described above, the DSU 4
REC1 in 1.5M path units when power is turned on / off
4 may occur.

However, in this embodiment, the SDH transmission apparatus 11 always keeps the multi-frame synchronization of the 1.5 M path sent from the DSU 4 and synchronizes with the RINH detection when it detects the RINH, and also assigns a pre-allocated backup. 1.5M with warning prohibition information based on detected RINH inserted in bits
Since the multiframe is generated and sent to the terminal device 5, it is possible to prevent the REC from continuing to be generated while the power of the DSU 4 is turned off, and to provide a 1.5M path when the power of the DSU 4 is turned on / off. The instantaneous REC alarm 14 of the unit can also be prevented from being generated.

Next, an embodiment of the SDH transmission apparatus according to the present invention will be described. FIG. 3 is a circuit diagram of an embodiment of the SDH transmission apparatus according to the present invention on the DSU4 connection side, and FIG. 4 is an SDH transmission apparatus on the DSU4 connection side according to the present invention.
1 shows a circuit configuration diagram of an embodiment of a system transmission device. FIG.
In FIG. 4 and FIG. 4, the same components are denoted by the same reference numerals.

In the SDH transmission device 11 shown in FIG. 3, the optical / electrical converter 111 is connected to the 6.3 from the subscriber line 2.
The 12 Mbps optical signal is converted into an electric signal, and the electric / optical converter 122 converts the 6.312 Mbps electric signal into an optical signal to interface with the subscriber line 2 of the high-speed digital leased line service. Further, the 6M frame termination unit 112 synchronizes with the 6M frame and extracts the RINH bit from the frame bit.

The 1.5M path separation section 113 is configured to use 6.312
The 1.5 M unit path data (# 1 of TS1 to TS24 in FIG. 2) and the status (# 1 of S1 to S4 in FIG. 2) are separated from the input data string of Mbps. RINH detector 1
14 performs detection / release protection and retention of the RINH signal.
The 1.5M frame synchronization section 115 outputs a synchronization signal synchronized with the status in units of 1.5M paths.

The 1.5M frame generator 116 independently generates an ST multiframe of a 1.5M unit path. The switching circuit 117 detects the status ST from the 1.5M path separation unit 113 and the status ST generated by the 1.5M frame generation unit 116 by the RINH detection unit 114.
Switching is performed by the NH signal. 1.5 Mbyte multiplexing unit 11
8 converts 1.5M path data and ST into a VC-11 path by 1.5-byte multiplexing, or reverse conversion.

The new synchronization interface 119 includes a plurality of V
C-11 path and VC-2 path are multiplexed and STM-1
(Synchronous Transport Module Level LI: Synchronous Transport Module Level 1) 155.52 Mbps optical signal or its inverse conversion. The 1.5M path multiplexing section 120 stores the data of the separated 1.5M unit path and the ST
Is again multiplexed with data having a service speed of 6.312 Mbps. The 6M frame generation unit 121 inserts the generated 6M frame into data without a frame.

4 is different from the SDH transmission apparatus 11 shown in FIG. 3 in that the RINH detection unit 114, the 1.5 frame synchronization unit 115, and the 1.5M frame Generator 116, switching circuit 11
7, the data from the 1.5-byte multiplexing unit 118 is input, and the RINH signal is converted to a 6M frame generating unit 125.
A difference is that a 1.5 frame synchronizing unit 124 for outputting to

Next, the operation of the SDH transmission apparatus 11 shown in FIG. 3 will be described. First, a normal operation will be described. 6.312 Mbps from DSU4 in the upstream direction
When the SDH transmission device 11 receives the optical signal, the optical signal is converted into an electric signal of 6.312 Mbps by the optical / electrical converter 111 and the 6M frame terminating unit 112 and the 1.5M path separating unit 1 are converted.
Hand over to 13. The 6M frame terminating unit 112 synchronizes with the 6M frame, extracts the RINH bit from the frame bits, and passes it to the RINH detecting unit 114.

In the 1.5M path separation unit 113, 6.31
The 1.5M unit path data (TS1 to TS24, # 1 in FIG. 2) and the status ST (S1 to S4, # 1 in FIG. 2), which are valid data, are separated from the 2 Mbps data string, and the data is 1.5M. Is passed directly to the byte multiplexing unit 118 and
Is a 1.5 Mbyte multiplexing unit 118 via a switching circuit 117
And to the 1.5 frame synchronization unit 115.
1.5 frame synchronization section 115 passes a signal synchronized with input status ST to 1.5 frame generation section 116. 1.
The 5-frame generating unit 116 independently generates a status ST synchronized with 1.5 frames.

In the switching circuit 117, the RINH detector 11
The ST from the 1.5M path separation unit 113 and the ST independently generated by the 1.5M frame generation unit 116 are switched according to the on / off state of the RINH signal that has been detected / release protected and held in step 4. Normally, since the RINH signal is off, ST from the 1.5M path separation unit 113 is selected. In the 1.5 Mbyte multiplexing unit 118, the data and the ST of the 1.5 M unit path are combined with the
The data is passed to the new synchronization interface 119 on the -11 path. The new synchronization interface 119 multiplexes a plurality of VC paths, and multiplexes a plurality of VC paths according to SDH (New Synchronization Hierarchy).
The signal is converted into an optical signal of 55.52 Mbps, STM-1, and relayed.

In the downstream direction, the SDH transmission apparatus 11 receives the 155.52 Mbps optical signal and reverses the ST operation in the new synchronization interface 119.
Each VC path is separated from M-1 and distributed according to the setting. The 1.5 M-byte multiplexing unit 118 extracts 1.5 M unit path data and ST from the VC-11 path received from the new synchronization interface 119, and transfers the data and the ST to the 1.5 M path multiplexing unit 120. The 1.5 M path multiplexing unit 120
1.5M received from byte multiplexing unit 118
The unit path data and ST are inserted into a predetermined position in the 6.312 Mbps data sequence, and the 6M frame generation unit 121
Pass to

The 6M frame generating section 121 inserts the generated 6M frame into the received 6.312 Mbps data string without a frame, and passes it to the electrical / optical converter 122.
In the electric / optical converter 122, the received 6.312 Mbp
s electrical signal is converted to a 6.312 Mbps optical signal, and D
Send to SU4.

Next, the operation when the DSU is turned off will be described. When the power of DSU4 is turned off, RI
A 6M frame with the NH bit on is transmitted from DSU4. When the RINH detector 114 detects the above-mentioned RINH, the SDH transmission apparatus 11
7, the status input to the 1.5-byte multiplexing unit 118 is changed from the ST output from the 1.5M path separation unit 113 to the spare bit generated by the 1.5M frame generation unit 116 by the RINH. Is switched to the 1.5M path ST multiframe to which is assigned.

The 1.5 M byte multiplexing section 118
The data of the M unit path and the ST from the switching circuit 117 are multiplexed by the 1.5 M byte multiplexing method, and are multiplexed on the VC-11 path and passed to the new synchronization interface 119. The new synchronization interface 119 multiplexes a plurality of VC paths, and
After converting to STM-1, which is a 155.52 Mbps optical signal defined by DH, the signal is transferred to the terminal device 5 through the SDH transmission device 12.

At this time, if the timing of the ST multi-frame from the switching circuit 117 is different from the timing of the ST multi-frame of the DSU 4, the terminal device 5 sets the instantaneous R in 1.5M path units.
EC occurs. However, in this embodiment, the ST multiframe from the switching circuit 117 is based on the signal from the 1.5M frame synchronizing unit 115, and the 1.5M frame generating unit 1 which always keeps the 1.5M multiframe synchronizing.
16, the instantaneous REC in the unit of 1.5 M path does not occur in the terminal device 5.

When a certain period of time has passed since the power was turned off, DSU4
Stops transmitting the 6M frame with the RINH bit on, turns off the power and turns off the output. In this case, the 6M frame termination unit 112 enters the REC state, and the frame synchronization is not achieved, so that the RINH bit cannot be extracted. However, since the RINH signal is held in the ON state by the RINH detection unit 114, the 1.5M frame generation unit 116 The generated ST continues to be selected.

Next, the operation when the DSU power is restored will be described. When the power of the DSU 4 is turned on from off, a 6M frame in the RINH bit off state is transmitted again. The 6M frame termination unit 112 in the SDH transmission device 11 establishes synchronization of the transmitted 6M frame,
The RINH bit off is sent to the RINH detection unit 114. R
When receiving the RINH bit OFF for the release protection time or longer, the INH detection unit 114 releases the holding of the RINH signal in the ON state.

Thus, the RINH detection unit 114 controls the switching circuit 117 to output the 1.5M
The ST generated by the frame generation unit 116 is switched to the ST output from the 1.5M path separation unit 113. in this case,
If the timing of the ST multiframe generated by the 1.5M frame generation unit 116 differs from that of the restored ST multiframe from the restored DSU 4, an instantaneous REC in 1.5M path units occurs in the terminal device 5. However, as mentioned above,
In this embodiment, the RINH signal detected by the RINH detection unit 114 is assigned to spare bits in the ST multiframe generated by the 1.5M frame generation unit 116, and the
The signal is sent to the H-method transmission device 12, and as described later, the SDH-method transmission device 12 detects the RINH signal assigned to the spare bit in the ST multiframe of the 1.5M path.
Since the data is inserted into a predetermined bit in the frame bit F of the M frame and transferred to the terminal device 5, the terminal device 5
The instantaneous REC in 1.5M path units is inhibited by the H signal.

Next, the operation of the SDH transmission apparatus 12 shown in FIG. 4 will be described. In the upstream direction, ST5.555 Mbps optical signal from the SDH transmission apparatus 11
M-1 is received by the new synchronization interface 119, separated into a plurality of VC-11 paths and VC-2 paths, and input to the 1.5M byte multiplexing unit 118. 1.5 Mbyte multiplexing unit 11
8 represents the input VC-11 path or VC-2 path,
The data is separated into 1.5M unit path data and status ST.

The 1.5M path multiplexing section 120 multiplexes the separated 1.5M unit path data and ST again into the data having the service speed of 6.312 Mbps. The 6M frame generation unit 125 generates the 6M frame
Insert a frame. Data from the 6M frame generation unit 125 is converted to 6.312 Mb by the electrical / optical converter 122.
After being converted into an optical signal of ps, it is transmitted to the terminal device 5.

Here, when the power supply of the DSU 4 is turned off, the ST multiframe of the 1.5M path in which RINH is assigned to the spare bit and the data of the 1.5M unit path are stored in the SDH of FIG.
The data is extracted from the 1.5-byte multiplexing unit 118 in the system transmission device 12, multiplexed by the 1.5 M-path multiplexing unit 120 into data having the service speed of 6.312 Mbps, and supplied to the 6-M frame generating unit 125.

At this time, the 1.5M frame synchronization section 124
Is 1.5M extracted from the 1.5-byte multiplexing unit 118
The ST multiframe of the path is input, and it is detected that RINH is inserted into a known spare bit previously allocated thereto, and RINH is set to 6 based on the detection result.
It is supplied to the M frame generation unit 125 and the 6M shown in FIG.
RINH is inserted at a predetermined bit position in the frame bit F defined by the standard in the frame.

In this way, when the power supply of the DSU 4 is turned off, the 6M frame generation unit 125 generates and fetches a 6M frame of the regular standard in which the RINH bit is inserted at a predetermined bit position of the frame bit F, and the The optical signal is converted into an optical signal having a service speed of 6.312 Mbps by the optical converter 122 and transferred to the terminal device 5.

In the downlink direction, 6.31 from the terminal equipment 5
The 2 Mbps optical signal is transmitted to the SDH transmission apparatus 12 shown in FIG.
After converting it into an electric signal of 6.312 Mbps by the optical / electrical converter 111 in the inside, the 1.5 M path separating section 113 converts it to 6.3.
1.5M which is valid data from 12Mbps data string
The unit path data (TS1 to TS24, # 1 in FIG. 2) and the status ST (S1 to S4, # 1 in FIG. 2) are separated.
Transfer to 1.5 M byte multiplexing section 118.

In the 1.5 Mbyte multiplexing section 118, 1.5
The data of the M unit path and the ST are loaded on the VC-11 path by the 1.5 M byte multiplexing method, and the
Hand over to 9. The new synchronization interface 119 multiplexes a plurality of VC paths, converts the multiplexed paths into STM-1 which is an optical signal of 155.52 Mbps defined by SDH (new synchronization hierarchy), and transmits the relay transmission path 13 to the SDH transmission apparatus 11. To transfer through.

As described above, in the embodiment described with reference to FIGS. 1 to 4, the 6.312 Mbps subscriber line (LI point) of the high-speed digital leased line service with the user premises speed of 1.544 Mbps is connected to the SDH transmission apparatus. The SDH transmission apparatus terminates the 6M frame, separates the data of the 1.5M unit path, and divides the data into S.
In a high-speed digital leased line service system for transmitting data between DH system transmission devices using a 1.5-byte multiplexed VC-11 path, the SDH system transmission device 11 on the DSU connection side uses the DSU4
Always take 1.5M path multi-frame synchronization from
When the RINH is detected, RIMH is assigned to the spare bit in the multi-frame of the 1.5M path and is transferred to the terminal device 5, so that the generation of an alarm in the terminal device 5 when the DSU 4 is turned off is prevented. In addition, the instantaneous REC alarm of 1.5M path unit at the time of DSU power ON / OFF can be prevented.

Next, another embodiment of the present invention will be described. FIG. 5 is a block diagram showing another embodiment of the high-speed digital leased line service system according to the present invention. In the figure, the same components as those of FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. In FIG. 5, the subscriber line section 2 between the DSU 4 and the terminal equipment 5 is 6.3 Mbytes multiplexed (VC-21 path).
Are extended by SDH transmission devices 17 and 18 connected by a relay transmission line 19. When the DSU 4 is turned off, the DSU 4 assigns a RINH signal to 6.312 Mbps data, that is, a 6 M (bit) frame, and sends it to the SDH transmission apparatus 11.

FIG. 6 is a block diagram showing another embodiment of the SDH transmission apparatus according to the present invention. The SDH transmission devices 17 and 18 each have the same configuration, stop the termination of the 6M frame, and transmit the data and status to the other SDH transmission device via the 6.3 Mbit multiplexed VC-21 path.

In FIG. 6, the optical / electrical converter 171 is
The 6.312 Mbps optical signal from the subscriber line 2 is converted into an electric signal, and the electric / optical converter 175 converts the 6.312 Mbps optical signal into an electric signal.
By converting an electric signal into an optical signal, an interface with the subscriber line 2 of the high-speed digital leased line service is performed.
The 6.3 M byte multiplexing unit 172 converts the data and ST of the 6.3 M path into a VC-21 path by 6.3 M bit multiplexing.
Or perform the inverse transformation.

The new synchronization interface 173 includes a plurality of Vs.
The C-21 path is multiplexed and the STM-1 155.52M
bps optical signal and output to the SDH transmission device 17 (when the new synchronization interface 173 is in the SDH transmission device 18), or of the STM-1 input from the SDH transmission device 18. 155.52M
bps optical signal is separated into a plurality of VC-21 paths (the new synchronization interface 173 is used for the SDH transmission apparatus 1).
7). 6M frame generator 174
Inserts the generated 6M frame into data without a frame.

In this embodiment, 6.312 Mbps
Since the data is transmitted as it is, the VC-
Since it is necessary to carry 21 paths, the line use efficiency between the SDH transmission apparatuses is reduced to 1/4 as compared with the embodiment of FIG. 1, but 6M frame bits are also transmitted transparently to the terminal station. Therefore, the problem of REC alarm generation in the terminal equipment due to non-RINH transmission does not occur. Further, in this embodiment, SD compared to the previous embodiment
The configuration of the H-system transmission devices 17 and 18 can be further economically reduced in circuit scale, and the restrictions can be reduced in terms of component mounting of the devices.

[0050]

As described above, according to the present invention,
6.312 Mbps subscriber line (LI point) for high-speed digital leased line service with 1.544 Mbps user premises speed
Is extended, the line use efficiency between the SDH transmission apparatuses can be quadrupled as compared with the case where the 6M frame is transmitted as it is by terminating the 6M frame and passing the data of the 1.5M unit path. .

According to the present invention, the SSU on the DSU connection side
The DH system transmission apparatus always synchronizes the multi-frame of the 1.5M path from the DSU, and when detecting the RINH, allocates the RIMH to the spare bit in the multi-frame of the 1.5M path and transfers the RIMH to the terminal station apparatus. Therefore, DSU
Alarm can be prevented from being generated in the terminal device while the power is off, and an instantaneous REC alarm can be prevented from being generated in units of 1.5 M paths when the DSU is turned on / off.

Further, according to the present invention, since only the ST multi-frame generating unit and the switching circuit are added to the conventional SDH transmission apparatus, the circuit scale is small and economical, and restrictions are also imposed on the component mounting of the apparatus. Can be reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of a high-speed digital leased line service system according to the present invention.

FIG. 2 is a configuration diagram of an example of a high-speed digital leased line service / subscriber line frame used in the method of the present invention.

FIG. 3 shows the SDH transmission apparatus (D) of the present invention used in FIG.
FIG. 3 is a block diagram of an embodiment (SU side).

FIG. 4 is a block diagram of an embodiment of an SDH transmission apparatus (terminal station connection side) of the present invention used in FIG. 1;

FIG. 5 is a configuration diagram of another embodiment of the high-speed digital leased line service system according to the present invention.

FIG. 6 is a block diagram of another embodiment of the SDH transmission apparatus of the present invention used in FIG. 5;

FIG. 7 is a configuration diagram of a high-speed digital leased line service system without extension by an SDH system transmission device.

FIG. 8 is a block diagram of an example of a conventional high-speed digital leased line service system in a normal state.

FIG. 9 is a configuration diagram of an example when a DSU power supply is turned off according to a conventional high-speed digital leased line service system.

[Explanation of symbols]

 Reference Signs List 1 User home section 2 Subscriber line section (LI point) 3 Terminal 4 Home apparatus (DSU) 5 Terminal equipment 11, 17 SDH system transmission apparatus (DSU connection side) 12, 18 SDH system transmission apparatus (Terminal apparatus connection side) 13, 19 relay transmission line 111, 171 optical / electrical converter 112 6M frame termination unit 113 1.5M path separation unit 114 RINH detection unit 115, 124 1.5M frame synchronization unit 116 1.5M frame generation unit 117 switching circuit 118 1.5 M byte multiplexing section 119, 173 New synchronous interface 120 1.5 M path multiplexing section 121, 125, 1746 M frame generating section 122, 175 Electrical / optical converter 172 6.3 6.3 M bit multiplexing section

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-7-30985 (JP, A) JP-A-6-164533 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04J 3/00-3/26

Claims (6)

(57) [Claims] 1. A plurality of user service sections including a home device having a first service speed and a subscriber line section having a second service speed higher than the first service speed including a terminal device. SDH transmission devices are connected in cascade to extend the subscriber line section, and the plurality of SDH transmission devices are connected.
VCs faster than the second service rate between
In a high-speed digital leased line service transmitted over 11 paths, the home device transmits data, status, and frame bits.
At the second service rate in frame units consisting of
Output to the station device, and the power of the home device itself is
When turned off, no unnecessary alarm is generated at the terminal equipment.
The RINH signal for ensuring that the frame bits
Inserted into the pre-allocated bits in the frame
Output from the plurality of SDH transmission apparatuses,
The SDH transmission device on the side is output from the home device.
The frame of the second service rate is input and
And terminates the RI
Detecting whether an NH signal is included;
When the RINH signal is not included in the frame
Is valid data from the data and status in the frame.
Data and valid status only after separation and multiplexing
Generate a module to be transmitted on the VC path and
SDH system on the terminal device connection side of the H system transmission device
Relay transmission to a transmission device;
When the RINH signal is included, the
From the data and status, valid data and valid status
And then multiplexes them based on the RINH signal.
Newly generated alarm prohibition information during the valid status
Transmitted on one of the VC paths assigned to the reserved bits of
A transmission module to generate a plurality of SDH transmission devices.
To the SDH transmission device on the terminal station connection side
And a step of joining the transmission, the terminal apparatus connected among the plurality of SDH system transmission apparatus
The SDH system transmission device on the side of the terminal is connected to the SD device on the side of the home device connection side.
From the transmission module input from the H system transmission device
Separating the valid data and valid status
Alerting the spare bit in the transmission module
Detecting whether or not prohibition information is included;
When the alarm prohibition information is not included, the separation
The Valid Status plurality of data including the valid data was
A second sub-status consisting of a status including
And generates a first frame of the service speed to the terminal device.
Forwarded and when the alarm prohibition information is included,
The data including the separated valid data and the valid status
Status and the pre-assigned bits
The frame bits into which the RINH signal is inserted.
Generating a second service rate frame, and
Transferring the alarm prohibition information in the high-speed digital leased line service. 2. The first service rate is 1.544M.
bps and the second service rate is 6.312M
bps, and the transmission rate of the transmission module is 15
5.52 Mbps and the frame is 6.312 Mbps
bps, and the VC path is V
2. The method according to claim 1, wherein the path is a C-11 path. 3. A first service rate including the home device.
In a high-speed digital leased line service system having a 544 Mbps user home section and a second service rate 6.312 Mbps subscriber line section including a terminal station apparatus, when the power of the home apparatus is turned off, the terminal station A RINH signal for preventing an unnecessary alarm from being generated in the device is inserted into a pre-assigned bit in the frame bits, and the data and status are transmitted at 6.312 Mbps from the home device toward the terminal device. And the frame
A first reception for receiving a first frame of mbits
Means, the first receiving means received by the first receiving means.
First detection for detecting the RINH signal from within a frame
Means, the first receiving means received by the first receiving means.
Valid data in the data from the frame and the status
After being separated from the valid status in the
Overlap with the first detection means.
The alarm prohibition information generated based on the RINH signal
Module with the spare bit of the effective status
A first SDH transmission device that outputs the module to the VC-11 path, and a second reception device that receives the module transmitted from the first SDH transmission device via the VC- 11 path.
Communication means, and the mode received by the second reception means.
Separate the valid data and valid status in the module
And detects the alarm prohibition information in the spare bit.
Separation / detection means, and the separation / detection means
When alarm prohibition information is detected, the valid data is
Including data and status including the valid status
And a RINH signal generated based on the alarm prohibition information.
Is the frame video inserted in the pre-assigned bits.
Frame generating means for generating a 6.312 Mbps second frame multiplexed with a packet and transmitting the second frame to the terminal device
And a second SDH system transmission device having: a high-speed digital leased line service system. 4. A service rate of 1.544 including a home device.
A plurality of SDHs connected in cascade to extend the subscriber line section between a user's home section of Mbps and a subscriber line section of a service speed of 6.312 Mbps including the terminal equipment.
An SDH transmission device on the connection side of the home device , wherein the home device has data, status, frame bits,
The service speed of 6.312 Mbp
s, the signal is output to the terminal device, and
Unnecessary alarm at the terminal device when the body power is turned off
The RINH signal for preventing the occurrence of
Inserted in the pre-assigned bits of the
And outputting the frame from the in-home device at 6.312 Mbps to the terminal device.
A terminator for terminating the frame to be transmitted in the direction to achieve frame synchronization; and the RINH from the frame terminated in the terminator.
A detection unit for detecting a signal, a separation unit for separating the data and status of 1.5 M units pass from the frame is terminated at the terminal end, based on the separate status by the separation unit, the off < a synchronization section for synchronizing with a frame; and when the detection section detects the RINH signal, alarm prohibition information is inserted into bits allocated in advance according to the synchronization timing from the synchronization section. A first generation unit that generates a status multiframe of a 5M unit path, and a status separated by the separation unit during normal times when the detection unit does not detect the RINH signal , and the detection unit detects the RINH signal. Time, a switching circuit for selecting the status multi-frame from the first generating unit, and a status or status selected by the switching circuit. A multiplex that multiplexes a multi-frame and data from the demultiplexing unit and then converts the multiplexed data into a VC-11 path, or performs inverse conversion for demultiplexing data of a plurality of VC-11 paths into data and a status. And a plurality of VC-11 paths from the multiplexing unit, and multiplexes these to transmit a signal of 155.52 Mbps,
For a 155.52 Mbps signal input from the outside, an interface for demultiplexing into a plurality of VC-11 paths, and the data and status separated by the multiplexing unit are multiplexed to generate a 6.312 Mbps frame. And a second generating unit for transmitting the data. 5. The SDH transmission according to claim 4, wherein the first generation unit allocates the alarm prohibition information to a spare bit in a status multiframe of the 1.5M unit path and inserts it. apparatus. 6. A service rate including an in-home device of 1.544.
And Mbps user home zone, between the subscriber line section of service rate 6.312Mbps including terminal equipment, a plurality
SDH transmission devices are cascaded to extend the subscriber line section, and the plurality of SDH transmission devices
During the period, VC11 packets with a service speed of 155.52 Mbps
An SDH system transmission device on the connection side of the terminal station device in the high-speed digital leased line service for transmitting data over a private network, wherein the SDH system transmission device is connected to the home device among the plurality of SDH system transmission devices.
The service from the SDH transmission apparatus according to claim 4
Input via VC11 path with 155.52Mbps
Signal into a plurality of VC-11 paths, and a plurality of VC-
An interface unit for multiplexing the plurality of VC-11 paths when an 11 path is input, generating a 155.52 Mbps signal, and transmitting the generated signal to an SDH system transmission apparatus connected to the home apparatus; It is entered from the data and status and the end portion of the frame bit frame synchronization and terminates the frame of 6.312Mbps multiplexed, data 1.5 M units pass from the frame that is terminated by the termination a separation unit for separating the status and, V after multiplexing the data and status from the separation unit
Converted to a C-11 path and passed to the interface unit,
The plurality of VC- separated by the interface unit
A multiplexing unit that performs an inverse conversion of separating the data of 11 paths into data and a status, and a pre-assigned bit of the status separated by the multiplexing unit , when the power of the home device is turned off.
A file transmitted at 1.544 Mbps from the home device.
Based on the RINH signal included in the frame, the home interior
The SDH transmission device according to claim 4, which is connected to a device.
A detector alarm prohibition information included in the status made is the signal to be output is detected whether 1.5M path unit is inserted, the data and status separated by the multiplexing unit
In, when the alarm prohibition information is detected by said detecting means, interpolation to the bits the RINH signal preassigned
Multiplex the input frame bits to 6.312 Mbps
And a second generation unit for generating the frame of the above and transmitting the generated frame to the terminal station device.