JP3524304B2 - Signal processing method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a call control processor in an I interface switch and a call processor with a signal processor interposed between a subscriber line / trunk line accommodated in the I interface switch. The fixed length signal read from the memory in the control processing unit is transmitted to the subscriber line / relay line as a state converted into a variable length signal by the signal processing unit, while the variable length signal from the subscriber line / relay line is Further, after being written once in the memory in the call control processing device as a state converted into a fixed length signal by the signal processing device,
The present invention relates to a signal processing method for receiving processing.

[0002]

2. Description of the Related Art From an ISDN terminal to an I interface (I
SDN user / network interface) A signal to a switch (hereinafter simply referred to as a switch) (subscriber line signal) or a signal between the switches (relay line signal) is generally an arbitrary combination / order of a plurality of variable length elements. Are arranged as variable length (format) signals arranged in the above, but as a technique relating to the transmission and reception of these variable length signals in the call control processing device, for example, a paper “I Interface Switch” has been used so far. Signal processing method "(Technical report of the Institute of Electrical and Information Engineers SE
87-85, page 2) are known.
In this case, as typified by the function sharing of the signal processing device (layer 2) and the upper processing device (layer 3), in the signal processing device, the setting release of the data link, the order control of reception and transmission, the reception, etc. The variable length signal from the subscriber line / relay line is transferred as it is to the exchange processing software of the upper processing unit. In the exchange processing software, the variable length signal is fixed to the element length of the constituent element, and the order of each constituent element is also converted into a predetermined fixed length format signal (fixed length signal) before the A variable length signal reception analysis is being performed. On the other hand, conversely, when transmitting a signal from the exchange to the subscriber line / relay line, the fixed length signal is converted into a variable length signal composed of only preset signal elements by the exchange processing software. , Sent on the subscriber line / relay line.

[0003]

However, as in the prior art described above, the conversion processing software performs the conversion processing from the variable length signal to the fixed length signal and the conversion processing from the fixed length signal to the variable length signal. In this case, the processing load due to the signal format conversion processing on the exchange processing software increases rapidly, and due to the decrease in processing capacity due to this,
Degradation of exchange services will be unavoidable. An object of the present invention is to enable a call control processor to process a signal on a switching processing software as a fixed length signal at high speed without the need for mutual conversion processing between a variable length signal and a fixed length signal by the switching processing software. The signal processing method is provided.

[0004]

SUMMARY OF THE INVENTION Basically, on the subscriber line / relay line, the fixed length signal read from the memory in the call control processing device is converted into a variable length signal by the signal processing device. On the other hand, the variable length signal from the subscriber line / relay line is once written in the memory in the call control processing device as a state of being converted into the fixed length signal by the signal processing device, and then received. To be achieved.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS. First, the main structure of the exchange according to the present invention will be described. FIG. 1 shows the structure as an example. Internal configuration of each of the call control processing device 1g and the signal processing device 1a, and these devices 1g and 1a
Although the connection relationship between the signal processing device 1a and the signal processing device 1a is shown, a subscriber line / relay line (not shown) is connected to the signal device 1
It has been accommodated via b. As shown,
The signal processing device 1a includes a signal device 1b, a signal processing processor 1c, an individual memory 1d of the signal device, an inter-memory signal transfer control device 1e, and an inter-device bus coupling circuit 1f, and the call control processing device 1g includes: In addition to the main processor (for executing exchange processing software) 1h, the main memory 1i, and the inter-device bus coupling circuit 1j, other elements required for exchange processing are included in the respective configurations. Inter-device bus coupling circuit 1
Call control processor 1g and signal processor 1a via f and 1j
However, when the fixed format corresponding to the signal type is set to be transferred to the signal processing apparatus 1a by the call control processing apparatus 1g so that the signal processing apparatus 1a can be updated at any time, the signal processing apparatus 1a In 1a, the fixed length signal read from the call control processor 1g is converted into a variable length signal while the signal type is extracted from the fixed length signal and the fixed format corresponding to the signal type is referenced. While being sent on the subscriber line / relay line as
The variable length signal from the subscriber line / relay line has a signal type extracted from the variable length signal, and is referred to a fixed format corresponding to the signal type, and is converted to a fixed length signal as a call control processing device. It can be written once in 1 g and then processed for reception.

FIG. 2 also shows a signal type-corresponding fixed format transfer setting sequence from the call control processor to the signal processor when the exchange is initialized. In this case, each time the switch is initialized, the invalid information element identifier is first transferred and set by the switching processing software from the call control processing device to the signal processing device (process 201). The invalid information element identifier here means that when a fixed length signal from the signal processing device is received and processed by the switching processing software in the call control processing device, information is set in correspondence with the information element forming the signal. It is for determining whether or not it is present, and is regarded as closed information in the system. In the signal processing device, the invalid information element identifier from the call control processing device is set in the individual memory, but this setting is not canceled until the exchange is initialized again thereafter. After the transfer setting of the invalid information element identifier, the information transfer frame (I frame) fixed to the signal processing device from the call control processing device by the exchange processing software is set to correspond to the message type (signal type). The long format (including the information element identifier and its installation position, etc.) is set for transfer (process 202), but the transfer setting for this fixed length format is repeated for the number of message types (process 203). In the signal processing device, the fixed length format sequentially transferred from the call control processing device is set in the individual memory, and this setting is similar to the invalid information element identifier, and thereafter, until the exchange is initialized again, It cannot be canceled. When the fixed length format corresponding to the message type is set in the signal processing device, the variable length / fixed length signal to be converted is converted into the fixed length / variable length signal while referring to the fixed length format corresponding to the signal type. It only has to be converted.

As described above, each time the switch is initialized, the message type compatible fixed length format is set to be transferred to the signal processing apparatus. However, the message type compatible fixed length format is set to be transferred to the signal processing apparatus. Is required to be updated and set at any time even when the exchange is in operation, triggered by a change in the configuration of some information elements. FIG. 3 shows the update setting sequence of the fixed length format corresponding to the message type during the operation of the exchange. In this case, when the call control processing device updates and sets the signal type-corresponding fixed format to the signal processing device, the signal processing device is first notified of the update request (process 301) and then fixed to the signal type-corresponding fixed format. The format is updated and set (process 302). When there are a plurality of information elements related to the change, the above processing is repeated for the number of information elements related to the change (processing 303).

FIG. 4 also shows the structure of an example of a fixed length format corresponding to the message type. Although the fixed length format of the I frame differs depending on the message type, the structure of the fixed length format is generally shown in FIG. According to this, in the fixed-length format, the number of information elements 4b to be set in the fixed-length format is set in addition to the message type 4a of Layer 3, and the number of information elements 4b A unique information element name (information element identifier) 4c is set as a pair with the setting position 4d of the information element. Incidentally, the setting position 4d referred to here means that when a certain byte position on the fixed length format is set as a reference position (for example, the first byte position (protocol identifier setting position), as will be described later) Relative distance to the information element setting start position (in bytes)
And is set in advance while considering the maximum value of the information element length that each information element can take.

As can be seen from the above, a fixed length signal (fixed length I frame) is bidirectionally transmitted between the signal processing device and the call control processing device. Show. As shown in the figure, in the fixed length signal, the protocol identifier 5a, the call number length 5b, the call number 5c and the message type 5d are indispensable constituent elements, and in addition, the number of information elements 5e required for each message, 5f, 5
It is configured as a form to which g, ... Of these components, the call number 5c has a field length set to the maximum length that a call number can generally take, and the effective length of the information set in the field is a value set as the call number length 5b. Is determined by. The information element is the information element 5
There are variable-length information elements such as e and 5f and fixed-length information elements such as the information element 5g. Among them, the variable-length information element includes the information element identifier 5h, the information element length 5i, and the information element content 5j. The information element content 5j is set to the maximum length that can be taken by the size of the area, but the effective length of the information set in the area depends on the value set as the information element length 5i. It has been determined.

Now, here, when the signal processing device receives a variable length I frame from an ISDN terminal (the same applies to a variable length I frame from a trunk line), the variable length signal is changed to a fixed length signal. The signal conversion process will be described below with reference to FIG. That is, in the signal processing device I
When the variable length I frame from the SDN terminal is received through the subscriber line (process 601), first, the message type is extracted and determined from the received I frame, and the fixed length format corresponding to the message type is preset. The selected fixed-length format group is selected and determined (process 602). Then, the write size for later determination of the write size is initialized to "0" (process 603), and the protocol identifier, call number length, call number and message type extracted from the received I frame are sent. The credit fixed length I frame is set to a predetermined value (process 604). At that time, the write size is updated by adding the effective length of the information set on the fixed length I frame for transmission to the initial write size (process 605). After that, the preset invalid information element identifier is set to all the information element identifiers on the fixed length I frame for transmission (process 60).
6) With reference to the fixed-length format that has already been selected and determined, for the information element set in the reception I frame, the setting position (write start position) on the transmission fixed-length I frame is determined from the information element identifier. ) Is determined (process 607). Next, whether each information element has a variable length or a fixed length is determined from the information element identifier (step 608). If the information element has a variable length, the information element identifier, the information While the element length and the information element content are set to the set position on the fixed length I frame for transmission, which is obtained from the fixed length format (process 609), if the information element also has the fixed length. For example, the information element identifier and the information element content are set at the set position on the fixed length I frame for transmission, which is obtained from the fixed length format (process 610).

As described above, each time the setting of the information element on the fixed length I frame for transmission is completed, the write size is further updated based on the length of the information element (process 611). By comparing the updated write size with the received I frame length, it is determined whether or not the setting of the information in the received I frame on the fixed length I frame for transmission has been completed (processing. 612). In this determination, if all the settings have been completed, the fixed length I frame for transmission is transmitted to the call control processing device as a fixed length signal, and a series of processes is completed (process 613). . Also, if it is determined that all the information elements have not been set, as long as the updated write size does not match the received I frame length, the unfixed information element has its transmission fixed length I. The setting position (writing start position) on the frame is determined, and the same process is repeatedly performed (processes 607 to 61).
2).

Next, the signal conversion processing from the fixed length signal to the variable length signal when the fixed length I frame from the call control processing apparatus is received by the signal processing apparatus will be described with reference to FIG. It seems If the signal processing device receives the fixed length I frame from the call control processing device (process 70).
1) In the signal processing device, the protocol identifier, the call number length, the call number, and the message type are extracted from the received I frame, and the predetermined value is set on the variable length I frame for transmission (process 702). Further, the fixed length format corresponding to the message type is selected and determined from a preset fixed length format group (process 703). Next, the information element identifier in the received I frame is referred to according to the order defined on the fixed length format selected and decided (process 70).
4) If the corresponding information element identifier is set at the setting position obtained from the fixed length format and the information element is a variable length element, the information element identifier, the information element length and the information element content are for transmission. It is set on the variable length I frame (process 705). Further, if the corresponding information element identifier is set at the setting position obtained from the fixed length format and the information element is a fixed length element, the information element identifier and the information element contents are the variable length I frame for transmission. It is set above (process 706). However, if an invalid information element identifier is set as the information element identifier in the received I frame, no setting is made on the variable length I frame for transmission (process. 70
7). After that, while referring to the fixed length format,
It is judged whether or not the information element related to the setting this time is the final information element in the fixed length format (process 70).
8) If it is the final element, the variable length I frame for transmission is transmitted as a variable length signal to the ISDN terminal on the subscriber line, and a series of processing is completed (processing 709). . Also, if the information element related to the setting this time does not correspond to the final information element in the fixed-length format, until it corresponds to the final information element, it is the variable length / fixed length for the unset information element. / It is determined that it is one of the invalid information element identifiers, and the same processing is repeatedly performed (processings 704 to 70).
8).

Finally, as a layer 3 message, R
Taking the example in ELease COMPlete (channel release and call number release completion notification, message type: 1011010), how the signal from the ISDN terminal is converted into a fixed length signal by the signal processing device will be described in detail. Show. First, Fig. 8 shows REL as a layer 3 message.
The information content about ease COMPlete is shown. As shown in the figure, the information elements include a protocol identifier (required), a call number (required), a message type (required), a reason display (optional), and a display (optional), and FIG. 9 shows a fixed format compatible with RELEase COMPlete. Are shown (see FIG. 4). Incidentally, in this example, the protocol identifier setting position is set as the reference position, and each setting position of the information element (reason indication, display) is shown as a relative distance from the reference position.

The invalid information element identifier is "H'FF".
(H 'indicates that "FF" is in hexadecimal display), no information element is shown in FIG. 10, a case where only the reason display is present as length 2 is shown in FIG. FIG. 12 shows the case in which only the reason is present as the length 9, and FIG.
3 respectively. Here, of FIGS. 10 to 13, for example, briefly describing FIG.
In the variable length I frame from the DN terminal, the protocol identifier, the call number, the message type and the reason display (length:
2) is included, but when this is received by the signal processing device, the protocol identifier, the call number, and the message type are used as a message common part over the 0th to 3rd byte positions in the fixed format. It is set, but the reason display is 4 on the fixed format.
It is set at the byte position. Regarding the display, since there is no display, the invalid information element identifier, that is, "H'FF" is set at the 36th byte position on the fixed format, and the call control processing device as a fixed length I frame. It has been sent to.

[0015]

As described above, according to the first to fifth aspects of the present invention, in the call control processing device, the exchange processing is not required to be performed by the exchange processing software between the variable length signal and the fixed length signal. A signal on software can be processed at a high speed as a fixed length signal.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a main part configuration according to the present invention in an I interface switch.

FIG. 2 is a diagram showing a signal type-corresponding fixed format transfer setting sequence from a call control processing device to a signal processing device when an I interface switch is initialized.

FIG. 3 is a diagram showing an update setting sequence of a fixed length format corresponding to a message type during operation of an exchange.

FIG. 4 is a diagram showing a general configuration of an example of a fixed length format corresponding to a message type.

FIG. 5 is a diagram showing an example of a fixed-length signal transmitted / received between a signal processing device and a call control processing device.

FIG. 6 is a diagram showing an example of a signal conversion processing flow from a variable length signal to a fixed length signal in the signal processing device.

FIG. 7 is a diagram showing an example of a signal conversion processing flow from a fixed length signal to a variable length signal in the signal processing device.

FIG. 8 shows REL as a layer 3 message.
Figure showing information contents about ease COMPlete

FIG. 9 is a diagram showing a fixed format compatible with RELEase COMPlete.

FIG. 10 is a diagram showing RELEase from an ISDN terminal.
Diagram showing how COMPlete is converted into a fixed-length signal by a signal processing device (No. 1)

FIG. 11 is a diagram showing RELEase from an ISDN terminal.
Diagram showing how COMPlete is converted into a fixed-length signal by the signal processing device (No. 2)

FIG. 12 is a diagram showing RELEase from an ISDN terminal.
FIG. 3 is a diagram showing how COMPlete is converted into a fixed-length signal by the signal processing device (No. 3)

[Fig. 13] Fig. 13 shows RELEase from an ISDN terminal.
FIG. 4 is a diagram showing how COMPlete is converted into a fixed-length signal by the signal processing device (No. 4)

[Explanation of symbols]

1a ... Signal processing device, 1b ... Signal device, 1c ... Signal processing processor, 1d ... Individual memory, 1e ... Inter-memory signal transfer control device, 1f, 1j ... Inter-device bus coupling circuit, 1h
... Main processor (for executing exchange processing software),
1i ... Main memory

(72) Inventor Hidehiko Kawanishi, 216 Totsuka-cho, Totsuka-ku, Yokohama-shi, Kanagawa Hitachi, Ltd. Information & Communication Division (72) Haruyoshi Kiyohisa 216 Totsuka-cho, Totsuka-ku, Yokohama, Kanagawa Hitachi, Ltd. Mfg. Co., Ltd. Information & Communication Division (72) Inventor Naoki Otani 216 Totsuka-cho, Totsuka-ku, Yokohama City, Kanagawa Prefecture Hitachi, Ltd. (Japanese) Japanese Telegraph and Telephone Corporation (56) Reference JP-A-8-223158 (JP, A) JP-A-5-68117 (JP, A) JP-A-5-56038 (JP, A) (58) Survey Areas (Int.Cl. ⁷ , DB name) H04L 12/02 H04Q 3/545

Claims (5)

(57) [Claims] 1. A memory in a call control processor in a state in which a signal processor is interposed between a call control processor in an I interface switch and a subscriber line / relay line accommodated in the I interface switch. The fixed length signal read out is transmitted to the subscriber line / relay line as a state converted to a variable length signal by the signal processing device, while the variable length signal from the subscriber line / relay line is fixed length signal in the signal processing device. A signal processing method in which the converted state is once written in the memory in the call control processor and then received. 2. A memory in the call control processor in the state where a signal processor is interposed between the call control processor in the I interface switch and the subscriber line / relay line accommodated in the I interface switch. The fixed length signal read out is transmitted to the subscriber line / relay line as a state converted to a variable length signal by the signal processing device, while the variable length signal from the subscriber line / relay line is fixed length signal in the signal processing device. A signal processing method in which the signal is once written in a memory in the call control processing device as a state converted to the above, and is received and processed, and each of the information elements and the information constituting the signal corresponding to the signal type The fixed length signal from the call control processing device is changed from the fixed length signal to the signal type from the fixed length signal in a state where the length and the order corresponding to the elements are preset in the signal processing device as a fixed format corresponding to the signal type. Is converted into a variable length signal while referring to the fixed format corresponding to the signal type, while the variable length signal from the subscriber line / relay line is extracted from the variable length signal. Above, a signal processing method for converting to a fixed length signal while referring to the fixed format corresponding to the signal type. 3. A memory in the call control processor in the state where a signal processor is interposed between a call control processor in the I interface switch and a subscriber line / relay line accommodated in the I interface switch. The fixed length signal read out is transmitted to the subscriber line / relay line as a state converted to a variable length signal by the signal processing device, while the variable length signal from the subscriber line / relay line is fixed length signal in the signal processing device. A signal processing method in which the signal is converted into a state in which it is once written in a memory in the call control processing device and then subjected to reception processing. After each of the information elements forming the signal and the length and order corresponding to the information elements are transferred and set in advance to the signal processing device as a fixed format corresponding to the signal type. The fixed-length signal from the call control processor is converted into a variable-length signal while the signal type is extracted from the fixed-length signal and the fixed format corresponding to the signal type is referred to, while the subscriber line / relay is connected. A signal processing method in which a variable-length signal from a line is converted into a fixed-length signal while extracting a signal type from the variable-length signal and referring to the fixed format corresponding to the signal type. 4. A memory in the call control processor in a state where a signal processor is interposed between a call control processor in the I interface switch and a subscriber line / relay line accommodated in the I interface switch. The fixed length signal read out is transmitted to the subscriber line / relay line as a state converted to a variable length signal by the signal processing device, while the variable length signal from the subscriber line / relay line is fixed length signal in the signal processing device. A signal processing method in which the signal is converted into a state in which it is once written in a memory in the call control processing device and then subjected to reception processing. After each of the information elements forming the signal and the length and order corresponding to the information elements are transferred and set in advance to the signal processing device as a fixed format corresponding to the signal type. The fixed-length signal from the call control processor is converted into a variable-length signal while the signal type is extracted from the fixed-length signal and the fixed format corresponding to the signal type is referred to, while the subscriber line / relay is connected. The variable length signal from the line is subjected to the initial setting process of the I-interface switch when the signal type is extracted from the variable length signal and the fixed length signal is converted while referring to the fixed format corresponding to the signal type. Instead, a signal processing method in which a fixed format corresponding to the updated signal type is set to be transferred from the call control processing device to the signal processing device at any time. 5. A memory in the call control processor in a state where a signal processing device is interposed between a call control processor in the I interface switch and a subscriber line / relay line accommodated in the I interface switch. The fixed length signal read out is transmitted to the subscriber line / relay line as a state converted to a variable length signal by the signal processing device, while the variable length signal from the subscriber line / relay line is fixed length signal in the signal processing device. A signal processing method in which the signal is converted into a state in which it is once written in a memory in the call control processing device and then subjected to reception processing. After each of the information elements forming the signal and the length and order corresponding to the information elements are transferred and set in advance to the signal processing device as a fixed format corresponding to the signal type. The fixed-length signal from the call control processor is converted into a variable-length signal while the signal type is extracted from the fixed-length signal and the fixed format corresponding to the signal type is referred to, while the subscriber line / relay is connected. The variable length signal from the line is converted into a fixed length signal while the signal type is extracted from the variable length signal and the fixed format corresponding to the signal type is referred to. A signal processing method in which a signal type corresponding fixed format is updated and set in a signal processing device by instructing the presence or absence of updating and the contents of updating for each element.