User manual

Chapter 2 Installation

The FIB1-E1 and FIB1-T1 fiber media converters' transmissions are transparent

to clock and data. They are designed to be placed in an existing E1 or T1 application

as an extension over fiber. When connected by fiber pair, the received analog signal

of each device is used to generate the transmitted optical signal. Because of their

transparent nature, they can be applied where the transmissions are unframed or

fractional without regard and with minimal configuration (only need to configure the

proper line code).

Figure 2-17 Transparent operation of FIB1-E1 and FIB1-T1

The FIB1-E1/T1 media converter incorporates a Far End Fault feature which

allows the converters on both ends of a pair of fibers to be informed when there is a

problem with one of the fibers. Without Far End Fault, it is impossible for a fiber

interface to detect a problem that affects only its Transmit fiber. When Far End Fault

is supported and enabled, a loss of receive signal (link) will cause the transmitter to

generate a Far End Fault pattern in order to inform the device at the far end of the

fiber pair that a fault has occurred. When the local receiver again detects a signal, the

local transmitter automatically returns to normal operation. The design of the FIB1-

E1/T1 utilizes the FEF to generate AIS to the connected CSU equipment, so that

alarms are transmitted in the traditional fashion when there is a fiber fault.

Figure 2-18 Far End Fault feature of FIB1-E1 and FIB1-T1

Fiber

fault

FEF received

E1 CS

AIS

FEF generated

AIS

E1 CS

Remote Side

Local Side