IDM-120N Telephone Optical Terminal 8-120 Channel Telephone Optical Terminal

📅May 12, 2026

Model：IDM-120N|Category：Telephone Optical Terminal

The IDM-120N multi-service optical terminal adopts a 19-inch 3U standard chassis; its total fiber transmission bandwidth is 155M, providing 2 shared line-rate 100M Ethernet interfaces, 4 groups of E1 transmission interfaces, and 120 telephone subscriber channels; the IDM-120N multi-service optical terminal provides 16 user interface slots; reserved multi-function card slots for flexible expansion, supporting any network topology;

Overview:

The IDM-120N multi-service optical terminal is a PCM integrated service fiber transmission device designed by our company using dedicated large-scale integrated circuits. Its total fiber transmission bandwidth is 155M, providing 2 shared line-rate 100M Ethernet interfaces, 4 groups of E1 transparent transmission interfaces, and 120 telephone subscriber channels. The E1 transmission channels comply with G.703 standard and adopt PCM30/31 framing; FXO and FXS can provide polarity reversal and caller ID functions. This device also features dual backup and hot-swappable power supply cards and ringing generator cards, greatly ensuring the reliability of service transmission. The IDM-120N telephone optical terminal can be widely used in public telephone network services of telecom operators such as China Telecom and China Netcom, as well as dedicated line information data services for electric power, banking, public security, military, and other sectors.

Product Features:

Adopts a 19-inch 3U standard chassis for easy installation.

4 groups of E1 transmission interfaces;

2 shared line-rate 100M Ethernet ports;

Provides 16 user interface slots;

Reserved multi-function card slots for flexible expansion, supporting any network topology;

Comprehensive function control switches and alarm indication functions;

Simple and complete network management functions, enabling online real-time configuration, query, fault statistics management, etc.;

Configuration Table:

No.	Name	Model	Description	Quantity
1	Equipment chassis backplane	IDM-120	19-inch 3U chassis, providing 19 card slots	1
2	E1 interface main control card	CMU-E1-120	Provides E1 interface access	1
3	Optical interface main control card	CMU-120	Provides 1 group of optical interface access. 2 groups of line-rate 100M Ethernet interfaces, 4 groups of E1 interfaces	1
4	Power supply card	PRU-120	Provides 1+1 power supply, whole system power. For FXO side, -48V input	2
5	Power supply and ringing generator card	RPRU-120	Provides 1+1 power supply, whole system power and ringing voltage. For FXS side, -48V input	2
6	FXO service card	8FXO-120	8-channel FXO interface, exchange side	16
7	FXS service card	8FXS-120	8-channel FXO interface, user side	16

In a single device configuration, only one of items 2 and 3 can be selected;

Technical Specifications:

Optical Interface

Interface Type	FC (SC etc. customizable)	Fiber Mode	Single-mode (multi-mode optional)
Fiber Rate	155Mbps ±50ppm	Wavelength	1310nm
Transmit Power	-2～-11dBm	Receiver Sensitivity	Better than -36dBm

E1 Interface

Bit Rate	2048Kbps	Line Code	HDB3
Standard Protocol	Supports ITU-T G.703	Impedance	75Ω/120Ω
Frame Structure	PCM30/31	Signaling	Channel Associated Signaling (CAS)

Ethernet

Interface Type	RJ-45	Transmission Rate	10/100Base-T 10M/100M
Standard Protocol	Supports IEEE802.3	Operating Mode	Full/half duplex/auto-negotiation