JP3458846B2 - Transmission line instantaneous interruption switching system at the time of failure and transmission line instantaneous interruption switching method at the time of use - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission line non-interruption switching system at the time of failure and a transmission line non-interruption switching method at the time of failure used for the same, and more particularly to non-interruption switching between a 0-system high-order group path and a 1-system high-order group path. Regarding how to do.

[0002]

2. Description of the Related Art Conventionally, in a transmission line non-interruption switching method at the time of failure, a 0-system high-order group path (hereinafter referred to as a high-order group path) and a 1-system path are made to coincide with each other in multi-frame phase, and both of them are divided into path units. The individual error states of the system are monitored for each frame, and the frames in which no error has occurred are selected for each frame. Here, as a switching trigger, B3 error and P
-AIS (Path-Alarm Indicio)
n Signal).

As shown in FIG. 5, a B3 error is a BIP for each frame in the transmitting device.
(Bit Interleaved Parity) operation is performed, the operation value is inserted into the B3 byte in the path overhead of the next frame and transmitted [see the transmitting side in FIG. 5 (a)]. BIP operation is performed on the B3 byte, and it is compared with the B3 byte of the next frame. If the comparison result does not match, it is determined that there is an error [Fig.
Refer to the receiving side in (b)].

The P-AIS is an AU (Administrator).
If all of the H1 and H2 bytes of the (Tive Unit) pointer are ALL “1”, it is detected that there is an ALM (alarm).

FIG. 6 shows an example of the configuration of a conventional path switching device based on a transmission line non-instantaneous interruption switching method at the time of failure. In FIG.
The multi-frame insertion unit 31 of the transmission side apparatus 2 periodically inserts a multi-frame pattern into the input signal in a specific path overhead with n frames as one cycle. In the transmitting side device 2, this main signal is branched into a 0-system main signal 100 and a 1-system main signal 200 and sent out to the transmission line.

In the receiving device 3, the multi-frame terminating unit 1
1 and 12 establish multiframe synchronization, and the phase control unit 1
Reference numeral 3 determines the phase difference between the multi-frame phase of the 0-system main signal 100 and the multi-frame phase of the 1-system main signal 200, and the phase difference absorption memory unit 14 is added so as to add a delay to the system main signal having the advanced phase. , 15 are controlled.

In the phase difference absorption memory units 14 and 15, a delay of a value designated by the control of the phase control unit 13 is inserted,
The 0-system main signal 101 and the 1-system main signal 201 are output as main signals having exactly the same phase. The trigger detection unit 17 detects the presence / absence of a B3 error and the presence / absence of P-AIS for each frame as a path switching trigger. The frame pulse generation unit 18 generates a frame pulse (FP) 301 indicating the beginning of a frame from the 0-system main signal 101 and the 1-system main signal 201, and passes it to the selection unit 20.

In the selection section 20, the presence or absence of the B3 error detected by the trigger detection section 17 and the presence or absence of the P-AIS are logically ORed by the AND gates 22 and 23.
-AIS is Low ("0") at ALM]
Is received as separate information for the 0 system / 1 system, and P-
The selection information (information on the system to be selected in frame units) is passed to the SEL (selector) unit 21 so as to select a normal frame that is determined to be absent together with the AIS and B3 errors. At that time, timing control is performed using the frame pulse 301 generated by the frame pulse generation unit 18 so that the selection system passed to the SEL unit 21 does not change in the middle of the frame.

In the faultless hitless memory unit 16, the time required by the trigger detection unit 17, the AND gates 22 and 23, and the selection unit 20, that is, the delay corresponding to the time required to determine the selection system is 0. System main signal 101 and system 1 main signal 2
Give to 01. The SEL unit 21 has a failure-free, non-disruptive memory unit 1
The 0-system main signal 102 and the 1-system main signal 202 from 6 are input at the same time, and for each frame determined by the presence / absence of a B3 error and the presence / absence of P-AIS of the main signals of both systems input from the selection unit 20 at the same time. Selection information is input, and either the 0-system or 1-system path is selected in frame units based on the selection information.

In this way, B is used in the same frame of both systems.
When 3 errors or P-AIS does not occur, select the system that does not generate B3 error or P-AIS for each frame, and switch when B3 error or P-AIS occurs in the same frame of both systems. Does not occur and the system selected in the previous frame is selected as is.

[0011]

However, the conventional failureless transmission line non-interruption switching method described above has the following problems. For example, as shown in FIG.
And a receiving side device 6 to terminate a section between the P-AI and
This is a problem when there is a device (hereinafter, referred to as a section terminator) 5 that detects and transfers S. The transmitting side device 3 and the receiving side device 5 are also section terminating devices.

In the section terminating device 5, when the AU pointer value changes, the section terminating device 5 changes the AU pointer value only when it continuously receives different AU pointer values for downstream signals. From the value (hereinafter, normal value pointer) to the P-AIS pointer value (hereinafter,
The transition to the P-AIS pointer) is decided to be changed when three consecutive matches (ITU-T).
G. 783 standard).

This operation will be described with reference to FIG. Received signal at section terminator 5 [Fig. 8 (a)]
Is changed from the normal value pointer to the P-AIS pointer [B in FIG. 8 (a)], the downstream transmission signal [FIG.
As the pointer value of (b)], the same value as the previous transmission pointer value is transmitted [D in FIG. 8 (b)].

In the receiving side signal [FIG. 8 (a)], P is repeated three times.
When the AIS pointer value is received [A in FIG. 8 (a)], the pointer value of the downstream transmission signal [FIG. 8 (b)] transits to P-AIS [C in FIG. 8 (b)]. Thus, the transfer time of P-AIS [E in FIG. 8 (b)]
Will always occur.

As shown in FIG. 7, the section terminator 5
Is present on the transmission line, the protection time is only E in FIG. 8B. However, when there are a plurality of section terminators, this protection time is superposed and P-AIS is applied at the receiving end. It takes a time of “the number of section terminators” × “protection time” to detect it. Therefore, when the number of section terminators differs depending on the route along which the path passes, the receiving side apparatus 6
Therefore, there will be a deviation in the time for detecting P-AIS.

In the case of the transmission line configuration shown in FIG. 7, what kind of operation is actually performed will be described with reference to FIG. When the main signal becomes P-AIS before branching in the transmitting side device 4, the output of the transmitting side device 4 [FIG. 9 (a)] shows that the 0-system main signal and the 1-system main signal have the same frame of P-AIS. It is output as information.

Regarding the 0-system main signal, when P-AIS is detected at the input of the section terminating device 5 [Fig. 9 (a)] [F in Fig. 9 (a)], the output of the section terminating device 5 [Fig. 9 ( Until the P-AIS is transferred as b)], a delay of protection time [G in FIG. 9 (b)] occurs.

Since there is no section terminating device for the 1-system main signal, the output [FIG. 9 (a)] of the transmitting-side device 4 is directly input. As a result, the signals input to the reception-side device 6 become the 0-system input of the reception-side device 6 [FIG. 9 (c)] and the 1-system input of the reception-side device 6 [FIG. 9 (d)], and the section terminator 5 The 0-system main signal for one vehicle will arrive later with the P-AIS information delayed.

As shown in FIG. 7, there are n section terminators between the 0-system main signal transmitting side apparatus 2 and the receiving-side apparatus 3 in FIG. FIG. 10 shows an operation example when a section disconnection occurs before the input of the multiframe insertion unit 31 when there are n−1 section terminating devices between the reception side device 3 and an unnecessary switching operation. Explain what happens.

Since the B3 error information is not delayed by the section terminating device, the multi-frame inserting unit 3 of the transmitting side device.
When a section break occurs before the input of 1, the 0-system B3 error information 212 and the 1-system B3 error information 213 are simultaneously generated in the receiving side device [H in FIG. 10].

Since there is one more section terminator in the 0-system transmission line in the P-AIS information, the 0-system P-AIS information is delayed by 2 frames with respect to the 1-system P-AIS information. FIG. 10]. The 0-system switching information 311 and the 1-system switching information 312 input to the selection unit 20 are as shown by J in FIG. As a result, the operation of the SEL unit 21 is originally 1
In the case of system selection, switching to system 0 will occur.

As described above, according to the prior art, the failure that occurs before the branching of each duplicated route in the transmission side device cannot originally be repaired by the non-interruptive switching system to which the present non-interruptive switching method is applied. There is a problem that a switching operation occurs for an event.

Further, this unnecessary switching operation is caused by the delay of the P-AIS transfer caused by the pointer processing in the section terminator of each route of 0 system / 1 system, as described above, and is caused on each route. It occurs depending on the correlation regarding the number of section terminators. Therefore, there is a problem to be solved in consideration of the section terminator in which all patterns exist on the actual network.

Therefore, an object of the present invention is to solve the above problems and to prevent unnecessary path switching in the receiving side device when an alarm occurs in the input part of the transmitting side device. An object of the present invention is to provide a failure-free transmission line non-instantaneous interruption switching system capable of coping with any network with respect to the number of installed termination devices, and a failure transmission-line uninterrupted interruption switching method used for the system.

[0025]

According to the present invention, there is provided a transmission line non-interruption switching system according to the present invention in which a frame received by a 0-system transmission line in a 0-system transmission line and a 1-system transmission line which are duplicated on the receiving side. When an anomaly is detected in the frame, the frame is switched to a normal frame received on the 1-system transmission path, and the switching trigger is generated by using the error presence / absence information in the overhead of each frame and the signal disconnection presence / absence information in the AU (Administrative Unit) pointer. An instantaneous transmission line non-interruption switching system, wherein the error presence / absence information is branched to the 0-system transmission line and the 1-system transmission line when the 0-system transmission line and the 1-system transmission line are simultaneously generated. Before the branch to the 0-system transmission line and the 1-system transmission line. When it is determined that it is due to the cause that occurs in the
The arrival time difference between the signal disconnection presence / absence information on the system transmission line and the 1-system transmission line is corrected.

In the failure-free transmission line non-instantaneous interruption switching method according to the present invention, an abnormality is detected in the frame received by the 0-system transmission line in the duplexed 0-system transmission line and 1-system transmission line. Sometimes, the frame is switched to a normal frame received on the 1-system transmission path, and the switching trigger is used as an error presence / absence information and AU (Administration) in the overhead of each frame.
A method for switching a transmission line without interruption during failure using a signal disconnection presence / absence information in a traverse unit) pointer, wherein the error presence / absence information is generated simultaneously in both the 0-system transmission line and the 1-system transmission line. It is judged that it is caused by the cause before it is branched to the 0-system transmission line and the 1-system transmission line, and at that time, a delay is inserted in the signal disconnection presence / absence information to add the 0-system transmission line and the 1-system transmission line. The arrival time difference of the signal disconnection presence / absence information is corrected.

That is, the method for switching between transmission lines without interruption during failure according to the present invention is SDH (Synchronous Digi).
tal Hierarchy) transmission system,
A multi-frame is constructed by using the path overhead of the high-order group path, and the multi-frame phase of the 0-system path and the 1-system path that pass through the duplicated routes on the receiving side are matched and the error of the high-order group path that has passed through both routes is eliminated. The present invention relates to a switching method for detecting and selecting a frame without any interruption and without error in units of higher-order group paths.

More specifically, the method for switching between transmission lines without interruption during a failure according to the present invention is B3 detected by the trigger detector.
If the error information is generated in both systems at the same time, a trigger judgment unit that judges the cause before the branch to each route is provided, and for the P-AIS information detected by the trigger detection unit in this trigger judgment unit, By inserting a delay,
The arrival time difference of P-AIS information is corrected by each route.

The selection unit sequentially reads the error information delayed by the trigger determination unit, and controls the switching of the SEL unit so that a normal frame is selected in frame units.
This makes it possible to prevent an unnecessary switch from occurring due to a difference in transfer delay of P-AIS information between both routes after branching, for a failure that has occurred before branching to each route.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a transmission line non-instantaneous interruption switching system according to an embodiment of the present invention. In FIG. 1, the transmission line non-interruption switching system at the time of failure according to one embodiment of the present invention is different from FIG.
The configuration is the same as that of the conventional transmission line non-disruptive switching system at the time of failure shown in (1), and the same components are denoted by the same reference numerals. In addition, the operation of the same component is similar to the conventional one.

In FIG. 1, when the B3 error information detected by the trigger detection unit 17 is generated in both systems at the same time, the trigger determination unit 19 determines that it is due to the cause before branching to each route, and trigger detection is performed. P-AI detected in part 17
By inserting a delay in the S information, the arrival time difference of the P-AIS information is corrected by each route.

In the selecting section 20, the error information delayed by the trigger judging section 19 is sequentially read, and switching control is performed on the SEL (selector) section 21 so as to select a normal frame in frame units. According to the above-described method, in the present embodiment, it is possible to prevent unnecessary switching from occurring due to a difference in transfer delay of P-AIS information between both routes after branching, against a failure that occurs before branching into each route. .

FIG. 2 is a block diagram showing a detailed configuration of the trigger determination section 19 of FIG. The trigger determination unit 19 will be described with reference to FIG. In FIG. 2, the trigger determination unit 19 includes a shift register 41, 42 and a latch unit 43.
, SEL units 44 and 45, conversion point detecting unit 46, AN
It is composed of D (and) gates 47 and 48 and an OR (or) gate 49.

The trigger determination unit 19 includes the 0-system B3 error information 402, the 1-system B3 error information 403, the 0-system P-AIS information 401, and the 1-system P-AI detected by the trigger detection unit 17.
The S information 404, the frame pulse (FP) 301 generated by the frame pulse generation unit 18, the 0-system delay information 405 and the 1-system delay information 406 given from the outside of the system are input, and the result of the trigger determination unit 19 is selected. To part 20
Selection information for each system, 1 system (0 system switching information 407, 1
It is passed as system switching information 408).

The structure of the trigger determination unit 19 will be described below. In addition, 0 system B3 error information 402, 1 system B3 error information 403, 0 system P-AIS information 401, 1 system P-A
The IS information 404 is all negative logic, Low (“0”) when there is an ALM (alarm), and Hi when there is no ALM.
("1").

The 0-system B3 error information 402 and the 1-system B3 error information 403 are input to the OR gate 49, and the output of the OR gate 49 is input to the latch unit 43. SEL section 4
In 4 and 45, the selection side is determined by the output state of the latch section 43.

The output of the SEL section 44 selects the information that has passed through the shift register 41 when the output of the latch section 43 is Low, and selects the path that does not pass through the shift register 41 when it is Hi. The SEL unit 45 is similar to the SEL unit 44,
As the output, when the output of the latch unit 43 is Low, the information that has passed through the shift register 42 is selected, and when it is Hi, the path that does not pass through the shift register 42 is selected.

The latch unit 43 holds the output when the input data is Low, and clears the held output by the clear control from the change point judging unit 46. The change point determination unit 46 detects that the outputs of the shift registers 41 and 42 change from Low to Hi and performs clear control.

The shift register 41 inputs the 0-system P-AIS information 401 and sets the set value of the 0-system delay information 405 indicating the number of frames by an integer value of 0 or more and the frame pulse 301.
Delay the output according to and. Shift register 4
2 gives an output delay to the input of the 1-system P-AIS information 404 in accordance with the set value of the 1-system delay information 406 indicating the number of frames and the frame pulse 301 with respect to the input of the 1-system P-AIS information 404.

FIG. 3 is a time chart showing the operation of the transmission line non-instantaneous interruption switching method according to an embodiment of the present invention.
FIG. 4 is a diagram showing an operation focusing only on signal input / output in the individual operation example of FIG. The operation of the transmission line non-instantaneous interruption switching method according to the embodiment of the present invention will be described with reference to FIGS.

Signals input to the trigger determination unit 19 include 0-system B3 error information 402, 0-system P-AIS information 401, 1-system B3 error information 403, and 1-system P-AIS detected by the trigger detection unit 17. The information 404, the frame pulse 301 generated by the frame pulse generator 18, and the 0-system delay information 403, 1 whose value is determined by the setting
This is system delay information 404. In FIG. 3, the 0-system delay information 403 is described as “n” and the 1-system delay information 404 is described as “0”. The signals output from the trigger determination unit 19 are 0-system switching information 407 and 1-system switching information 408.

The outputs of the shift registers 41 and 42 are input 0 system P-AIS information 401 and 1 system P- according to the set values of the 0 system delay information 403 and the 1 system delay information 404.
A delay is added to the AIS information 404. In the example shown in FIG.
The output of the shift register 41 is delayed by n frame pulses (a, b in FIG. 3), and the shift register 42 has no delay because the 1-system delay information is 0 (c, d in FIG. 3).

The output of the latch unit 43 holds the Low output when the 0-system B3 error information 402 and the 1-system B3 error information 403 simultaneously change to ALM (Low) (e in FIG. 7) (see FIG. 7). f), the output of the conversion point detection unit 46 is Low
When it changes to (g in FIG. 7), the holding is released (h in FIG. 7). The output of the change point detector 46 is the shift register 41,
When the output of 42 changes to no ALM (Hi) (i in FIG. 7), one frame pulse is output (g in FIG. 7).

The selection directions of the SEL units 44 and 45 are as follows: while the output of the latch unit 43 is Low (j in FIG. 7), on the output side of the shift registers 41 and 42, while the output of the latch unit 43 is Hi (FIG. 7). K), the 0-system P-AIS information 401 and the 1-system P-AIS information 404 that are not on the output side of the shift registers 41 and 42 (selection direction / SEL of the SEL unit 44 in FIG. 3).
Direction of selection of section 45).

The 0-system switching information 407 outputs ALM-present (Low) when either the 0-system B3 error information 402 or the output of the SEL unit 44 is ALM (Low). In the example shown in FIG. 3, the 0-system B3 error information 402 is L
When it is ow (e in FIG. 7), the output of the shift register 41 is L
When it is ow (1 in FIG. 7), it outputs Low.

Similarly to the above, if the 1-system B3 error information 403 or the output of the SEL unit 44 is ALM (Low), the 1-system switching information 408 has ALM (Lo).
w) is output. In the example shown in FIG. 3, when the 1-system B3 error information 403 is Low (e in FIG. 7), the shift register 4
When the output of 2 is Low (m in FIG. 7), Low is output.

FIG. 4 shows an operation in the case of focusing only on signal input / output in the above individual operation example. The operation will be described with reference to FIG. The 0-system delay information 40
5 is a case of "2", and 1-system delay information 406 is a case of "0".

When the 0-system B3 error information 402 and the 1-system B3 error information 403 are detected at the same time, the 0-system P-AIS information is delayed by 2 frames due to the delay information, and the 1-system P-AIS information is delayed.
-AIS information is output as 0-system switching information 407 and 1-system switching information 408 without delay. In the selection unit 20 in the subsequent stage of the trigger determination unit 19, since the switching information has the ALM in the same position in both the 0-system and the 1-system, the switching instruction is not issued to the SEL unit 21, so that the selection main signal changes. There is no.

As described above, when a warning is generated at the input unit of the transmission side device 2, unnecessary path switching can be suppressed in the reception side device 1. Also, 0 route and 1 route
The optimum delay information according to the number of installed section terminators existing on the system route is externally set to 0 system delay information 405, 1
By setting it as the system delay information 406, it is possible to deal with any network regarding the number of installed section terminators.

[0050]

As described above, according to the present invention, when an abnormality is detected in a frame received on the 0-system transmission line in the 0-system transmission line and the 1-system transmission line that are duplexed on the receiving side, 1 In a failure-free transmission line non-interruption switching system, which uses the error presence / absence information in the overhead of each frame and the signal disconnection presence / absence information in the AU pointer as the switching trigger When it occurs in both the 0-system transmission line and the 1-system transmission line at the same time, it is determined that it is due to the cause that occurred before the system was branched to the 0-system transmission line and the 1-system transmission line. By inserting a delay and correcting the arrival time difference of the signal disconnection presence / absence information on the 0-system transmission line and the 1-system transmission line, the receiving side can be used when an alarm occurs at the input unit of the transmitting side device. Can suppress unnecessary path switching in location, there is an effect that it is possible to cope with any network for Installation number of section termination device.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a transmission line non-instantaneous interruption switching system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a detailed configuration of a trigger determination unit in FIG.

FIG. 3 is a time chart showing an operation of a transmission line non-instantaneous interruption switching method at the time of a failure according to an embodiment of the present invention.

FIG. 4 is a diagram showing an operation focusing only on signal input / output in the individual operation example of FIG. 3;

5A and 5B are views for explaining presence / absence information of a B3 byte.

FIG. 6 is a block diagram showing a configuration of a transmission line non-instantaneous interruption switching system according to a conventional example.

FIG. 7 is a diagram showing an example of connecting a receiving device and a transmitting device connected to an SDH transmission line.

8A and 8B are diagrams showing the operation of the section terminator of FIG. 7.

9A to 9D are diagrams showing the operation of the transmission path configuration shown in FIG. 7.

FIG. 10 is a diagram showing an operation example when a section break occurs before the input of the multi-frame insertion unit of FIG. 6;

[Explanation of symbols]

1 Receiving side device 2 Sending device 11,12 Multi-frame end part 13 Phase controller 14,15 Phase difference absorption memory unit 16 Failure-free and instantaneous memory 17 Trigger detector 18 frame pulse generator 19 Trigger judgment section 20 Selector 21,44,45 SEL section 31 Multi-frame insertion part 41,42 shift register 43 Latch 46 Conversion point detector 47,48 AND gate 49 OR gate

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H04L 1/22 H04B 1/74 H04J 3/00

Claims (9)

(57) [Claims] 1. A normal frame received on the 1-system transmission line when an abnormality is detected in a frame received on the 0-system transmission line in the 0-system transmission line and the 1-system transmission line that are duplexed on the receiving side. The error presence / absence information and the AU (Ad
A transmission line non-instantaneous interruption switching system at the time of failure using signal disconnection presence / absence information in a minimalist unit pointer, wherein the error presence / absence information is generated simultaneously in both the 0-system transmission line and the 1-system transmission line. 0
Before branching to the 0-system transmission line and the 1-system transmission line, the trigger-judgment unit determines to be caused by the cause before the system-transmission line and the 1-system transmission line are branched. When it is determined that the signal disconnection presence / absence information is caused by the cause, the delay is inserted in the signal disconnection presence / absence information to correct the arrival time difference of the signal disconnection presence / absence information in the 0-system transmission line and the 1-system transmission line. A feature is a transmission line non-interruption switching system at the time of failure. 2. The 0-system transmission line and the 1-system transmission line,
SDH (Synchronous Digital H
The transmission line for instantaneous failure-free switching according to claim 1, wherein the transmission line is a transmission line for transmission. 3. The failure-free transmission line instantaneous interruption switching system according to claim 2, wherein B3 byte error information in the overhead is used as the error presence / absence information. 4. The P-AIS is used as the signal disconnection presence / absence information.
(Path-Alarm Indication Si
5. The system for switching transmission without interruption during a failure according to claim 2 or claim 3, characterized in that it is configured so as to use the same. 5. The failure-free transmission line non-interruption switching according to any one of claims 1 to 4, wherein the trigger determination means corrects the arrival time difference of the signal disconnection presence / absence information. system. 6. A normal frame received by the 1-system transmission line when an anomaly is detected in the frame received by the 0-system transmission line in the 0-system transmission line and the 1-system transmission line that are duplexed on the receiving side. The error presence / absence information and the AU (Ad
A method for switching a transmission line without interruption during failure using a signal disconnection presence / absence information in a minimalist unit pointer, wherein the error presence / absence information is generated simultaneously in both the 0-system transmission line and the 1-system transmission line. It is judged that it is caused by the cause before it is branched to the 0-system transmission line and the 1-system transmission line, and at that time, a delay is inserted in the signal disconnection presence / absence information to add the 0-system transmission line and the 1-system transmission line. A method for switching transmission lines without interruption during a failure, characterized in that the arrival time difference of the signal disconnection presence / absence information is corrected. 7. The 0-system transmission line and the 1-system transmission line,
SDH (Synchronous Digital H
7. The failureless transmission line non-instantaneous interruption switching method according to claim 6, wherein the transmission line is a transmission line for transmission. 8. The failure-free transmission line non-interruption switching method according to claim 7, wherein B3 byte error information in the overhead is used as the error presence / absence information. 9. The P-AIS is used as the signal disconnection presence / absence information.
(Path-Alarm Indication Si
9. The failureless transmission line non-instantaneous interruption switching method according to claim 7 or claim 8, characterized in that it is used.