Overview - FibroLAN FEM4 User And Installation Manual

Advanced FE/E1 Fiber Converters
1 – Overview
The FEM/FEM4 converter from FibroLAN is an ideal solution for extending your
2.045Mbps E1 copper based PBX, switch/router or Multiplexer over a variety of MM or
SM fiber optic interface links
The FEM device includes 4 Fast Ethernet channels and 1 E1 channel across a single
fiber link. The FEM4 models include 4 E1 ports.
Thus the main advantage of this device is the provided additional Fast Ethernet
connectivity, allowing the user to connect its IP traffic with E1 data across the same
F/O link.
The FEM/FEM4 unit has been designed to be deployed in pairs so that at each end of
the fiber link there is an FEM device.
The FEM/FEM4 unit multiplexes Fast Ethernet data and E1 data over the fiber trunk;
however, the active E1 channel reduces the Ethernet data bandwidth by 2Mbps.
AMI or HDB3 bipolar line code can be selected on the E1 copper interface.
The E1 port has a DS1 interface.
The FEM/FEM4 encapsulates E1 data into fast Ethernet frames that are transmitted
over the fiber link. These E1 frames are given the highest priority; they are transmitted
as soon as the transmission of an Ethernet frame is completed. On the receive side,
these frames are extracted from the Ethernet data flow and converted into timed E1
signals.
A built-in buffer stores incoming Ethernet frames when E1 frames are transmitted. Full
100Mbps data bandwidth is restored when no E1 signals are received.
The Ethernet ports can operate in two selectable user modes:
LAN mode: as a local switch with a fiber link interface
Aggregation mode: each Ethernet port forms with the F/O link a separate traffic path
to provide a physical level of security and separation between the users and to allow
traffic only between each user and the F/O link (traffic between users is blocked)
The LAN/Aggregation selection is performed by means of DIP switch S10
The FEM/FEM4 is available with a variety of multi-mode and single mode fiber
interfaces (distances ranging up to 150km) as well as single-fiber-strand (full bi-
directional traffic) models.
The FEM/FEM4 is standard "half-rack" size for economical installation in both rack-
mount and desktop modes. It is equipped with a reliable internal switching power
supply for extended MTBF. The optional DC power supply facilitates deployment in
Telco environments.
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