MRV Communications EM316SW-XY - Manual (Page 14)

Fiber Driver
®
EM316SW-XY
PN 1288003-001, Rev D2
6
2.2.2 Dual Converter
MODE1 ON
MODE0 OFF
Figure 3 -- Dual Converter Mode
In Dual Converter mode, the module incorporates two independent “copper 10/100 to Fiber Fast
Ethernet converters” for the price of a single converter. This combination doubles the density of
a central office chassis, allowing up to 30 converters in a managed 16-slot chassis.
The first converter uses ports P1 and P2. The second converter uses ports P3 and P4.
With LIN enabled, loss of link at a port receiver disables the transmitter of the paired port.
Downstream switches, routers, and other link-state dependant devices can accurately react to
changing link conditions. This feature is especially valuable in fault-tolerant network designs.
The module supports both LIN and FEFI for link status propagation in Dual Converter mode. In
this mode, LIN offers two functional options.
1) The basic LIN (FEFI disabled) maintains backwards compatibility with all MRV Fast
Ethernet media conversion modules as well as the common Far End Fault Indication
(FEFI). The SFP transceiver beacons (transmits a periodic signal) if there is no signal
detected on its receiver. This signal notifies the other side about the detected problem.
2) A revised LIN (FEFI enabled), which uses the FEFI standard to notify the other side
about a problem in the receive fiber. Beaconing is not necessary in this case.
The revised LIN is recommended if the other side of the link supports FEFI. Use basic LIN if the
remote device does not support FEFI.
A single DIP switch controls LIN for both converters, so both will use either LIN enabled or
disabled.