Filter
Top Products
14 Network Service Module
C613-03022-00 REV K
AT-AR048 NSM
The AR048 NSM provides a single unchannelised DS3 interface with two BNC
connectors for transmit and receive. The front panel of the AT-AR048 NSM is
shown in Figure 9 and the functions of the LEDs are described in Table 4.
Figure 9: AT-AR048 NSM
DS3 Interface
The AT-AR048 NSM provides a single standards-based unchannelised DS3
interface. The interface has the following features:
■ 44.736Mbit/s interface rate, 44.210Mbit/s payload data rate
■ Separate transmit (Tx) and receive (Rx) BNC connectors
■ 75Ω impedance
■ B3ZS line encoding
■ Automatic compensation for lines up to 135m (450feet)
■ Loop or internal timing
■ C-bit framing
■ Support for PPP and Frame Relay encapsulation
The interface meets the following specifications:
■ ANSI T1.103, Digital Hierarchy - Synchronous DS3 Format
■ ANSI T1.107, Digital Hierarchy - Formats
■ ANSI T1.231, Digital Hierarchy - Layer 1 In-Service Digital
■ RFC 2496 (DS3 MIB)
Table 4: AT-AR048 LEDs
LED State Function
Active Green Lit when the Line Interface Unit (LIU) is receiving a signal.
Loop Green Lit when any loopback is active.
LOS Amber Lit when the received signal is lost. This usually indicates a network
disruption, such as a cable being disconnected or a device failure.
LOF Amber Lit when the DS3 framer cannot extract valid frames from the
received signal.
AIS Amber Lit when an Alarm Indication Signal is detected.
FERF Amber Lit when a Far End Receive Failure signal is detected. This indicates
the far end is receiving an AIS, LOS, or LOF signal.
AIS
FERF
LOS
LOF
Loop
Activity
RX TX