JPH02266631A - Isdn basic access terminal equipment - Google Patents

Abstract

PURPOSE:To build up a high speed communication network able to send lots of information by using 2 B-channels so as to send/receive a signal 128Kb/s. CONSTITUTION:Channels B1 and B2 of two independent signals 64Kb/s are connected to a terminal equipment of a destination via an ISDN to eliminate the time difference between both the B-channels and the relative arrangement is made coincident between both the transmission reception terminal equipments. When the setting of the delay buffer 5 or 6 of the B-channel is finished, the transmission terminal equipment restores inserters 3, 4 to apply multiplex and demultiplex to an input signal 128Kb/s into a signal on the channels B1 and B2 by a DMUX 1 and the resulting signal is transferred to the reception terminal equipment via the ISDN. The reception terminal equipment uses a MUX 11 to multiplex the signal 128Kb/s, which is transferred to a data terminal equipment thereby applying communication of the signal 128Kb/s. Thus, even in a narrow band ISDN using the signal 64Kb/s as a basic hearer, the high speed digital communication of using the signal 128Kb/s is attained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an I5DN basic access terminal, and more particularly to a terminal that transmits and receives 128 Kb/S signals using two B channels.

[Conventional technology]

Conventionally, basic access subscriber terminals in ISDN were assigned two B channels (each with a capacity of 64 Kb/s) and were assumed to be used independently. Also R4Kb/
84Kb/S on public network because it is based on S.
It has generally been impossible to transmit information beyond this range.

[Problem to be solved by the invention]

The conventional ISDN basic access terminal described above is
With the recent transition to an information society, 64Kb/
It has the disadvantage that it cannot meet the need for sending and receiving information exceeding S. Currently, these issues are addressed through digital leased line services, but as digital leased line services naturally have significant restrictions on who can communicate with them, it is important to build a high-speed network that allows free communication with anyone, anytime, anywhere. Being watched.

[Means to solve the problem]

The ISDN basic access terminal of the present invention comprises 128
and means for demultiplexing the t+/S signal into a 64Kb/S signal.

means for multiplexing a 64 Kb/S signal into a 128 Kb/S signal;

Time-series pattern generation means for generating a time difference detection signal for detecting the relative time difference that occurs between two B-channel signals simultaneously output from a transmitting terminal via ISDN and reaching a receiving terminal, and the relative arrangement of both channels. and.

means for inserting a time difference detection signal into each of the two B channels at the transmitting side;

means for generating independently designated time delays in the two B channels on the transmitting side; means for detecting the time difference and the relative arrangement based on the time difference detection signals of the two B channels received from the ISDN; and swapping means for swapping the relative arrangement between the two B channels received from the ISDN.

[For production]

In this way, after connecting two independent 64Kb/S B channels to the destination receiving terminal via 15DN, eliminating time envy on both B channels, and matching the relative placement between the sending and receiving terminals, 2 B by receiving 128Kb/S signal
The current 64Kb/S narrow band I
SDN enables high-speed communication of 128Kb/S.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a flow diagram of the main parts of an embodiment of the I SDN basic access terminal of the present invention, and FIGS.
FIG. 2 is a diagram showing an example of a time difference detection signal generated by the time series pattern generator 2 shown in the figure.

In this embodiment, 128Kb/
The 64Kb/S signal is transferred to the ISDN using the B1 and B2 channels, and the receiving terminal converts it back to a 128Kb/S signal and sends it to the destination data device (not shown). It consists of a transmitting section, a receiving section, and an I5DN connecting section. The transmitter is 128Kb/
When generating a time difference detection signal for detecting the relative time difference and relative arrangement at the receiving terminal of the B, B, and B2 channels. A sequence pattern generator 2, an inserter 3.4 for inserting the time difference detection signal into the B, B2 channels, and an integer multiple (including O) of 8 frames (125 gs) each independently for the B1 and B2 channels. The receiver includes a variable delay buffer 5.6 that generates a delay, and detects a time difference detection signal from the received B, B2 channels, calculates the time difference between the B l * B two channels, and determines the relative arrangement. a time-series pattern detector 9 for B, .
Contains MUXII to multiplex B2 channels. l
The S/T interface 8 of the 5DN connection unit connects this terminal device to the S or T reference point of the ISDN specified in the CCITT recommendations, performs signal minute/synthesis matching,
The D protocol handler 7 sends and receives the D channel, which is an ISDN control signal channel.

Next, the operation of this embodiment will be explained.

When there is a signal input at 128Kb/S, the BI channel and B2 channel are connected to the destination terminal device via ISDN, and the time difference detection signal is sent to the time series pattern generator 2.
generates a numerical signal that increments by "1" every frame as shown in Figure 2, and the B channel receives "0 to 127" every frame, and the B2 channel receives "128 to 255" every frame. ” and inserter 3゜4
Insert from. Therefore, the most significant bit of the 8 bits of the B, B2 channel is 0'' for the B channel, and 1 for the B2 channel, so that the B, B2 channel can be discriminated.

The frames received on the receiving side are processed by a time-series pattern detector 9.
The number of each frame is detected, and the B1 channel and B2
Since there is a delay between the B channel and the B2 channel by the value where the difference in the corresponding frame number from the B channel differs from 128, this amount is notified to the transmitting terminal, and the transmitting terminal detects the delay of the B channel on the leading side. time difference in delay buffer,
For example, a delay of 3 frames is set. In addition, if the Bl channel and B2 channel received at the receiving terminal are arranged in the opposite direction to the arrangement at the transmitting terminal, the time series pattern detector 9 detects the "O" and "1" of the most significant bits of the frame. The swap switch 10 restores the normal arrangement. The transmitting terminal is B channel 1! Nobatsuhua 5
Or, when the settings in step 6 are completed, restore the inserter 3.4 and send the 128Kb/S input signal to DMUX1.
The signal is demultiplexed into two channels and transferred to the receiving terminal via the 15DN. At the receiving terminal, it is multiplexed by MUXII and 128
The data is transferred to the data terminal at Kb/S, and high-speed communication at 128 Kb/S is performed.

As a time difference detection signal, as shown in Fig. 3, the transmitting terminal
,, both B2 channels are kept at 0'', and the time series pattern generator 2 inserts, for example, an identifier X into the B1 channel and an identifier Y into the B2 channel into a certain corresponding frame simultaneously via the inserter 3.4.Reception. At the terminal, the time series pattern detector 9 detects the identifiers X and Y, checks their time and arrangement, notifies the transmitting terminal of the time difference of 3 frames, returns the arrangement to normal using the swapping switch IO, and then , on the transmitting side, a delay corresponding to the time difference 1, for example, 3 frames, notified from the receiving terminal is set in the delay buffer 6 of the leading B2 channel, and the inserter 3.
4 will be restored. [B] The relative time difference between frames at the receiving terminal is eliminated and the channel arrangement is normal due to [2]
.

128 Kb/
The S signal is demultiplexed and sent out, and the receiving terminal receives B, , B25.
-w-channel is multiplexed to 128 Kb/S by MUXI i and transferred to the connected data device.

Note that notification of the delay time difference from the receiving side to the transmitting side can be performed by the D channel or by the B channel in the opposite direction. Swapping can be performed at the sending terminal, or by forcibly specifying a channel by exchanging messages with an exchange during the connection process.

In the description of the present invention, ISDN terminals have been mainly described, but due to their nature, existing terminals, etc.
Needless to say, it also includes a terminal adapter for converting to an N interface.

〔Effect of the invention〕

As explained above, the present invention provides b/S of 64K to 128.
demultiplex into two B channels of b/S.

Transfer via I SDN, 128Kb/S at receiving terminal
By multiplexing into 128 Kb/S, high-speed digital communication of 128 Kb/S is possible even in a narrowband I5DN that uses 64 Kb/S as a basic bearer.

[Brief explanation of drawings]

FIG. 1 shows the l5DN basic access terminal of the present invention.
- A block diagram of the main part of the embodiment, FIGS. 2 and 3 are diagrams showing examples of time difference detection signals generated by the time series pattern generator 2 of FIG. 1. 1...DMUX, 2...Time series pattern generator, 3.4...
...Inserter, 5.6...Delay buffer, 7...D protocol handler, 8...
S/T interface. 9...Time series pattern detector. 10... Swap switch. 11...MUX.

Claims (1)

[Claims] 1. In an ISDN basic access terminal directly connected to an ISDN basic access interface, means for demultiplexing a 128 Kb/S signal into a 64 Kb/S signal; means for multiplexing, and generating a time difference detection signal for detecting the relative time difference that occurs between signals from two B channels simultaneously output from a transmitting terminal via ISDN to a receiving terminal and the relative arrangement of both channels. means for generating a time series pattern; means for inserting a time difference detection signal into each of the two B channels on the transmitting side; means for generating independently specified time delays in each of the two B channels on the transmitting side; means for detecting a time difference and relative arrangement based on received time difference detection signals of two B channels; means for instructing the delay means of a B channel that is ahead by the detected time difference to delay; I characterized in that it has a swap means for swapping the relative arrangement between two B channels.
SDN basic access terminal.