JP3035967B2 - Remote subscriber accommodation device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a remote subscriber accommodation device for multiplexing ISDN subscribers at remote locations.

[Prior Art] Conventionally, when an ISDN subscriber at a remote location is accommodated in an ISDN exchange, an IDLC (INTEGRAT) as shown in BELLCORE TR-000303 is used.
With ED DIGITAL LOOP CARRIER), 2B + D of remote ISDN subscriber line was time division multiplexed and connected to ISDN exchange.

FIG. 2 shows a connection configuration example of a conventional remote subscriber accommodation device.

In FIG. 2, ISDN subscribers at remote locations have network terminating equipment (NT) 31 and 32, and network terminating equipment (NT) 31 and
It comprises ISDN terminals (TA) 28 and 30 connected to S-INTERFACE BUS 27 and S-INTERFACE BUS 27 and 29.

In addition, since these subscribers are located at remote locations, in order to accommodate them in the ISDN exchange (SW) 41, they are first multiplexed by the multiplexer (RMUX) 36, and the primary group interface (DTI) 37
And 39 are connected to an ISDN exchange 41.

The primary group interface (transmission line 38) between the primary group interface devices 37 and 39 is based on IDLC shown in BELLCORE TR-000303, and time-division multiplexes the ISDN subscriber line 2B + D at a remote location to form a 24-channel system (1.544 MHz), 2B (2 × 64 KBPS) + D (16 KBPS) is multiplexed into, for example, 8 subscribers, and 18 channels out of 24 channels (8 × 8 KBPS)
(2B + 1 / 4D) = 18B) to use the interface configuration to connect to the higher-level ISDN exchange SW41.

On the higher ISDN exchange SW41 side, of these 24 channels
The D channel portion of 18 channels is taken out by the insertion / separation circuit 40, and layer 2 termination circuits (ET) 42 and 43 perform layer 2 termination.
And passes the information of the D channel layer 3 to the layer 3 processing unit (L3P) 44. If the layer 3 processing section 44 determines that the call is a packet-switched call, the information is passed to the packet-switching apparatus, and the packet-switched call is processed.

[Problems to be Solved by the Invention] In the conventional remote subscriber accommodating apparatus described above, a subscriber line at a remote location is time-division multiplexed and accommodated in an ISDN exchange on a primary interface with an ISDN exchange. Side terminates Layer 2 of the D channel of the remote subscriber line, so that the multiplicity limit of the remote subscriber line on the primary interface (for example, 1.5 Mbps at the primary interface)
Since there are only 24 channels in a system, the limitation is that even if 2B + D ISDN subscribers are multiplexed, only 8 or 9 subscribers can enter), and the D channel layer 2 on the ISDN exchange side
There was a disadvantage that the port of the termination circuit was restricted.

Means for Solving the Problems The present invention has been made in view of the above problems, and has been made in consideration of the problems described above. It is intended that the accommodating port on the exchange side also be a port unit of 23B + D primary late access.

To this end, the present invention provides a Layer 1 and Layer 2 termination circuit for an ISDN subscriber line, a Layer 1 and Layer 2 termination circuit for a 23B + D primary late access interface with a subscriber accommodating ISDN switch,
A B-channel switching switch for concentrating and multiplexing the B channel of an ISDN subscriber to a B channel on the primary late access, and a B channel packet layer 2 termination circuit for inserting and separating a B channel packet call on the B channel on the primary late access. Equipped, remote
The packet switching call of the ISDN subscriber line is configured to correspond to the packet switching call on the 23B + D primary late access interface.

[Operation] In the remote subscriber accommodation device having the above configuration, a plurality of ISs
The B channel of the DN subscriber is line-multiplexed and multiplexed to the B channel on the primary late access, and the B channel packet call is inserted and separated into the B channel on the primary late access so that the ISDN subscriber at the remote place can be primary. The group interfaces are accommodated irrespective of the time division multiplexing degree, and the accommodation ports on the ISDN exchange side are also set to 23B + D primary late access port units.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of a remote subscriber accommodation apparatus according to the present invention.

In FIG. 1, ISDN subscribers at remote locations include network terminating devices (NT) 5 and 6, and ISs connected to network terminating devices 5 and 6 via subscriber premises S-INTERFACE BUS1 and 2.
It is composed of DN terminals (TA) 3 and 4.

In addition, since these subscribers are in remote locations, to accommodate them in the ISDN exchange (SW) 21, the subscribers are temporarily multiplexed by the remote subscriber accommodating device 9, and the primary group interface device (DTI) 17.
And 20 are connected to an ISDN exchange 21.

The ISDN exchange 21 is processed by a call processor (CP) 26. The ISDN exchange 21 is a direct accommodating ISDN subscriber,
That is, ISDN subscriber line 22, network terminating device 23, subscriber premises S
-It also has an INTERFACE BUS 24 and an ISDN terminal (TA) 25.

In the remote subscriber accommodation device 9, ISDN subscriber lines 7 and 8
Waiting for the layer 1 termination circuits (LT) 10 and 12 and the layer 2 termination circuits (ET) 11 and 13 in the layer 1 termination circuits 10 and 12, the synchronization circuit of the ISDN subscriber line and the D channel separation multiplexing of 2B + D are provided. D channel is layer 2
Connected to termination circuits 11 and 13.

The primary interface between the remote subscriber accommodation device 9 and the ISDN exchange 21 is a 23B + D interface,
Layer 2 termination circuits 18 and 23B for processing the D channel
B channel packet layer 2 terminating circuits (L2B) 47 and 48 for inserting and separating B channel packets into and out of the device are provided. The D channel packet of the ISDN subscriber is transmitted and received by the layer 2 terminating circuits 11 and 13 of the remote subscriber accommodation device 9, and the remote subscriber control device (RLP) 16 analyzes the call control packet and the data packet.

The call control packet is converted to the layer 3 of the primary rate access interface with the upper ISDN exchange 21,
Primary rate access interface Layer 2 Layer 2 termination circuit 18, primary group interface device
The data is transmitted to and received from the higher-level ISDN exchange 21 via 17.

The layer 3 conversion processing in the remote subscriber control device 16 means, for example, in the case of a call from a remote subscriber, a call identifier in a message on the primary rate access side in order to correspond to layer 3 of the primary rate access interface. Is converted by the line number of the remote subscriber line / the link number (TEI NO) of the layer 2 of the subscriber line / the logical channel number of the D channel packet.
The primary access channel identifiers 23B and 30B indicated in Q931 of -T are channel numbers assigned to data packets of D channel packets to B channel packets having 23B, and the bearer service is 64 KBPS / packet service. The message from the primary rate access side is the reverse conversion.

Here, the D channel of the primary rate access interface 23B + D is a protocol according to CCITT I series Q931, and manages 23B and the logical channel number of each remote subscriber line number / D channel packet and the packet allocated to 23B. The B-channel correspondence is processed by the B-channel exchange switch (DLSW) 14 at the remote subscriber controller 16.

The data packet of the D channel packet of the ISDN subscriber is connected to the B channel packet layer 2 termination circuits (L2B) 47 and 48 on the primary for the packet allocated in advance and is converted.

In this way, remote ISDN subscribers are multiplexed and
The DN exchange 21 can be stored as a primary subscriber.

[Effects of the Invention] As described above, the present invention provides a layer 1 and layer 2 termination circuit of an ISDN subscriber line, and a layer 1 and layer 2 termination of a 23B + D primary late access interface with a subscriber housed ISDN exchange. Circuit, multiple IS
A B channel exchange switch for concentrating and multiplexing the B channels of the DN subscribers to the B channel on the primary late access, and a B channel packet layer 2 termination circuit for inserting and separating the B channel packet call on the B channel on the primary late access. Equipped, remote IS
Since the packet switching call of the DN subscriber line is configured to correspond to the packet switching call on the 23B + D primary late access interface, the remote ISDN subscriber can be accommodated regardless of the time division multiplexing of the primary interface, In addition, the accommodation port on the ISDN exchange side can also be set to a port unit of 23B + D primary late access.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a remote subscriber accommodation apparatus according to the present invention, and FIG. 2 is a block diagram showing an example of a conventional remote subscriber accommodation apparatus. 1 S-INTERFACE BUS for subscriber premises 2 S-INTERFACE BUS for subscriber premises 3 ISDN terminal 4 ISDN terminal 5 Network termination device 6 Network termination device 7 ISDN subscriber Line 8 ISDN subscriber line 9 Remote subscriber accommodation device 10 Layer 1 termination circuit 12 Layer 2 termination circuit 12 Layer 1 termination circuit 13 Layer 2 termination circuit 14 B-channel switching Switch 15 Interprocessor bus 16 Remote subscriber control device 17 Primary interface device 18 Layer 2 termination circuit 19 Transmission line 20 Primary interface device 21 ISDN exchange 22 ISDN Subscriber line 23 Network termination device 24 Subscriber premises S-INTERFACE BUS 25 ISDN terminal 26 Call processor 47 B channel layer 2 termination circuit 48 B channel layer 2 termination circuit 49 …… Packet switching

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H04Q 11/00-11/08 H04M 7/00 H04L 11/20

Claims (1)

(57) [Claims] Claims 1. When accommodating ISDN subscribers at a remote location in a subscriber accommodating ISDN exchange accommodating ISDN terminals applied to an integrated service digital network based on the CCITT recommendation I series, the ISDN subscriber at the remote location is identified. A remote subscriber accommodating apparatus comprising a multiplexed remote subscriber accommodating apparatus and accommodating as a 23B + D primary late access subscriber, comprising: an ISDN subscriber line layer 1 and layer 2 termination circuit; 23B + D primary late access interface layer 1 and layer 2 termination circuit with ISDN exchange accommodating subscribers, B channel exchange switch for concentrating and multiplexing B channels of a plurality of ISDN subscribers to B channels on primary late access, primary Insert and separate B channel packet calls into B channel on late access A remote subscriber accommodating apparatus, comprising: a B-channel packet layer 2 termination circuit, wherein packet switching calls on a remote ISDN subscriber line correspond to packet switching calls on a 23B + D primary late access interface.