JPS61133745A - Transmitter having loopback processing function - Google Patents

Abstract

PURPOSE:To attain a loopback test to each individual line by allowing a procedure supervisory section to eliminate apparently generation of an event against the limit condition and to transfer the collected reception data to a terminal device during the loopback test in a transmitter using two lines in parallel for transmission. CONSTITUTION:When it is supposed that the loopback of a line 8 is made effective, a transmission distribution control section 11 applies nearly all transmission data to a loopback forming section 12-1. Thus, the transmission loopback is formed by a route 19-1, a loopback forming section 15-1 and a reception multiplex section 16. Further, the reception side loopback is formed by an interface section 14-1, a loopback forming section 15-1 and a route 20-1. While the loopback test is conducted, the procedure supervisory section 17 transmits the loopback data to a terminal device 2 as reception data by taking the following countermeasure that it is regarded that no error takes place at the terminal device 2 even if violation of the limit condition takes place in the procedure.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Industrial Application Field The present invention is directed to a transmission device having a loop bank processing function, particularly a transmission device that performs transmission using one line, for example, two lines in parallel. In addition to providing a call-back function that can be selectively enabled for each line, a procedure monitoring unit is provided to apparently eliminate violations of procedural constraints that may occur during the call-back test, and the call-back test is optional. The present invention relates to a transmission device that can perform the following operations.

(B) Problems to be Solved by the Prior Art and the Invention Conventionally, when a data transmission system as shown in Figure 2 exists, each milestone point as shown in Figure 2 (■9■, ■, ■) has been known. A loopback function is provided at the position and a so-called loopback test is performed.

Conventionally, foldback tests are performed as described above.

Recently, the amount of data transmitted has increased and the transmission speed of modems has been increasing, but there are limits to the speed increases due to limitations in telephone lines (analog transmission).

As shown in FIG. 3, two sets of lines are used in parallel. In addition, in FIG. 2 and FIG. 3, 1 is a host data processing device.

Reference numeral 2 represents a terminal device, 3.4 each a modem, 5 and 6 each a transmission device, and 7 and 8.9 each a transmission line.

When attempting to perform the above loopback test under the configuration shown in Figure 3, since the state in which two sets of lines 8.9 are used in parallel is a normal operating state, the It is also desirable to conduct the test under conditions in which two sets of lines 8.9 are used in parallel. For this reason, conventionally, as shown in FIG.
(ii) Simultaneous returns at 0 points and ■ points, respectively, (
iii) respective simultaneous returns at 0 points and 0 points, (
iv) There was a loopback based on 0 points. However, when performing loopback as in (ii) or (iii) above, it is difficult to determine which line is at fault. For this purpose, consideration is given to making it possible to selectively enable the wrapping of each of the 9 points ■ and ■, and also to selectively enable the wrapping of each of the 0 points and the 0 point shown in the diagram. It has reached the stage where it will be done.

However, if we try to make this kind of selective efficiency effective, the first problem arises. That is, when the terminal device 2 receives the received data, for example, a DLE character followed by M<ACK or NAK, or ETB (end of block) or ETX (end of text) and the following 2 bytes. Minute BCC (CRC)
code), immediately after the above DLE character, immediately after the above ETB, etc., or 2 bytes of BC
If an undesired interval (an empty space B where no data exists) occurs between the bytes of C, a constraint on one procedure will be imposed and an error will occur.

Therefore, in the system as shown in FIG. 3 above,
If you try to perform loopback using only one of the lines, the amount of data that would originally have been transmitted using two sets of lines will now be transmitted on one set of lines. Therefore, it may become difficult to completely correctly comply with the above-mentioned procedural constraints.

(C) Means for Solving the Problems The present invention solves the above problems, and even if a situation arises in which the above procedural constraints cannot be observed, the above constraints are apparently observed. Prepare a procedure monitoring unit that performs such processing.

The present invention provides a transmission device that enables selective loopback as described in connection with FIG. 4 above. And for that reason 1
The transmission device of the present invention has a terminal interface section for the terminal device and a line interface section for the line side, and transmits data transmitted from the terminal device during communication between the terminal device and a remote device. In a transmission device that transmits the received data from the remote device by substantially evenly distributing it to at least two lines, and transmits the received data from the remote device to the terminal device; A transmitting side return generation unit is provided corresponding to each line while the signal is distributed to each line and then supplied to the line interface unit.

A receiving-side loopback creation section, a sending-side loopback creation section, and the above-mentioned transmission-side loopback creation section are provided between the line interface section that receives received data from the respective lines and the reception multiplexing section that aggregates the received data, corresponding to each line. The loopback route formed using the above-mentioned receiving-side loopback creation unit and the received data aggregated by the above-mentioned reception multiplexing unit are monitored for occurrence of situations that violate the constraints on the reception procedure, and are monitored to prevent situations that violate the above constraints. A procedure monitoring unit is provided to eliminate the appearance of occurrence, and 2 is configured to simultaneously or selectively enable the return routes created corresponding to each of the above lines, and a return test is performed to carry out the return. The present invention is characterized in that during the process, the procedure monitoring section apparently eliminates the occurrence of a situation that violates the constraint conditions and transfers the aggregated received data to the terminal device side. This will be explained below with reference to the drawings.

(D) Example FIG. 1 shows the configuration of an embodiment of the present invention.

Reference numeral 2.6 in the figure. a, : respectively correspond to FIG. 3, 10 is a terminal interface section, 11 is a transmission distribution control section, 12-1 and 12-2 are respectively a transmission side return generation section, 13
-1.13-2 is the transmission side line interface section, 1
4-1.14-2 is a receiving side line interface section,
Reference numerals 15-1 and 15-2 are receiving-side return generation units, and 16 is a reception multiplexing unit that aggregates data sent in parallel via the respective lines into one data string.

17 is a procedure monitoring section, and 18 is a return test control function section.

19-1 and 19-2 are respectively transmission return routes, 20-1
．． 20-2 each represent a reception return route.

During normal transmission processing, the transmission distribution control unit 11:
In other words, the data is distributed evenly to each of the two lines, passes through the return generation units 12-1 and 12-2, and is then transferred to the interface units 13-1 and 13-2.
Send from. On the other hand, interface parts 14-1 and 1
The data received from 4-2 are sent to the return generation unit 15-
1 and 15-2, and is guided to the reception multiplexing section 16. The reception multiplexing unit 16 aggregates the respective data sent from the two sets of lines into one data string, so to speak, and transfers the data to the terminal device 2 side. At this time.

The procedure monitoring unit 17 checks for violation of constraint conditions on the 2-procedure, and 1.During normal transmission processing, if a violation exists, it works to treat it as an error.

In contrast to the above, the following operation occurs during the return test.

In the case of the present invention, it goes without saying that there is a case where loopback is enabled for two sets of lines at the same time, but in this case, there is no substantial difference from the conventional method, so below, either one of the lines will be enabled. The manner in which line loopback is enabled will be described.

Now, assuming that loopback of the line 8 is enabled, the 2-transmission distribution control section 11 supplies, so to speak, all of the transmission data to the loopback generation section 12-1. As a result, the sending side loopback is performed by the route 1'9-1° loopback creation unit 15-1. It is formed by the reception multiplexing section 16. Also, the reception side loopback is performed by the interface section 14-1. Return creation unit 15-1.
It is formed by route 20-1.

2. As stated at the beginning of the specification of the present application, the case where a folding test is conducted using the folding route concerned.

The return data supplied to the reception multiplexing section 16 is likely to be interrupted, so that some portions of the received data created in the reception multiplexing section 16 may violate procedural constraints. In the procedure monitoring section 17,
Even if a violation of the constraints on one procedure occurs during a loopback test, the following measures are taken to prevent it from being considered as an error occurrence on the terminal device 2 side, and the above loopback data is treated as received data. The data is sent to the terminal device 2.

That is, characters, that is, return data (received data) transferred in serial form from the reception multiplexing section 16 are buffered and checked for violation of the above constraints. When looking at a string of returned data, there are cases in which even if there is a slight break in the continuity of the data, it is not considered an error, and cases in which such a break causes an error. In the former case, the nine-procedure monitoring unit 17 inserts a predetermined time filler into the data string in which the interruption has occurred, and sends out the data in a form that provides some degree of continuity. That is, when a character to be transmitted does not arrive even when the next character is to be transmitted after one character has been transmitted, that is, a so-called under-run state occurs, the 9-interval is widened and the next character is transmitted. Insert filler. On the other hand, in the latter case, the two-procedure monitoring unit 17 waits until the arrival of the next character before sending out the previous character, and sends out the previous character without any interval between them. Regarding the above-mentioned example of return on the receiving side, it may be considered that the procedure monitoring unit in the transmission device 5 on the host side shown in FIG. 3 performs similar processing.

(E) As described in detail, according to the present invention, by providing a one-procedure monitoring section, it is possible to carry out a return test for each individual line. Also, in the processing in the procedure monitoring section, it is necessary to provide a buffering means and to save time.
Relatively simple procedures such as adding filler and dispensing at one hour intervals made it possible to perform the desired fold test.

[Brief explanation of the drawing]

FIG. 1 shows the configuration of an embodiment of the present invention, and FIGS. 2 to 4 are explanatory diagrams for explaining the prerequisite problems of the present invention. In the figure, 2 is a terminal device, and 5 and 6 are transmission devices, respectively. 8.9 is a line, and 10 is a terminal interface section. 11 is a transmission distribution control section, 12 and 1.5 are return generation sections, and 13.14 are line interface sections, respectively. Reference numeral 16 represents a reception multiplexing section, 17 a procedure monitoring section, 18 a return test control function section, and 19 and 20 each representing a return route.

Claims (1)

[Claims] It has a terminal interface section for the terminal device and a line interface section for the line side, and substantially transmits data sent from the terminal device to at least two lines during communication between the terminal device and a remote device. In a transmission device that evenly distributes and transmits the data received from the remote device through the at least two lines, aggregates the data, and transfers the aggregated data to the terminal device, the data is distributed to the respective lines, and then the data is transmitted to the terminal device. A transmission-side loopback creation section is provided corresponding to each line while supplying the data to the line interface section, and between the line interface section that receives received data from each of the above-mentioned lines and the reception multiplexing section that aggregates the received data. a receiving-side loopback creation unit created corresponding to each line, a return route formed using the above-mentioned transmitting-side loopback creation unit and the above-mentioned reception-side loopback creation unit, and It is equipped with a procedure monitoring unit that monitors the occurrence of a situation that violates the constraints on the reception procedure regarding received data and apparently eliminates the occurrence of a situation that violates the constraints, and has a return route that is created corresponding to each of the above lines. are configured to simultaneously or selectively enable either one of them, and during the loopback test in which the loopback is performed, the procedure monitoring section apparently resolves the occurrence of a situation that violates the constraint condition and receives the aggregated reception. A transmission device having a loop back processing function, characterized in that data is transferred to the terminal device side.