4.6 Power Budget Calculations for DFG48000
PM’s with Fiber Media
Receiver Sensitivity and Transmitter Power are the parameters necessary to compute the power
budget. To calculate the power budget of different fiber media installations using DFG48000 products,
the following equations should be used:
OPB (Optical Power Budget) = PT (min) - PR (min)
where PT = Transmitter Output Power, and PR = Receiver Sensitivity
Worst case OPB = OPB - 1dB (for LED aging) - 1dB (for insertion loss)
Worst case distance = {Worst case OPB, in dB} / [Cable Loss, in dB/Km]
where the “Cable Loss” for 62.5/125 and 50/125µm (M.m) is 2.8 dB/km,
and the “Cable Loss” for 9/125 (Single-mode) is 0.5 dB/km
5.0 Introduction - DFG48000
Managed Fiber Switch Port Modules
This chapter describes each Port Module (PM), including appearance, functionality, and status
displays.
5.1 Inspecting the Package and Product
This section applies only to PMs shipped as separate items, i.e., DFG480XX Cards (Port Modules) not
factory installed in a DFG48000 PM slot. Examine the shipping container for obvious damage prior to
installing a DFG480XXPM; notify the carrier of any damage you believe occurred during shipment or
delivery. Inspect the contents of this package for any signs of damage and ensure that the items
listed below are included. This package should contain:
One (1) or more DFG480XX Cards with installation instructions and illustrations. Remove the
DFG480XX (s) from the shipping container. Be sure to keep the shipping container should you need to
ship any of the PMs separately at a later date. In the event there are items missing or damaged,
contact your supplier. If you need to return the unit, use the original shipping container if possible.
5.2 DFG480XX Card (Port Module) Description
An important feature of the DFG48000 is the use of Port Modules for flexible mixed-media
connectivity to RJ-45 and fiber media. Since the DFG48000 Switches have dual-speed capability for
copper ports, the 6 or 8-port interfaces are designed to support all standard Ethernet media types at
10 or 100Mps speed. Each DFG480XX PM provides six or eight ports for connecting Ethernet
segments with its individual connector type and media. For a list of DFG480XX Port Module types,
refer to Section 1.2
Each DFG480XX PM is individually described in the following sections.
NOTE:
The port #1 on the RJ-45 ports on all the modules, either all RJ-45 ports or used for COMBO
module is set as (=) other user ports.
5.2.1 DFG380XX, 4@10/100Mbps RJ-45 and 2@100Mb multi-mode FX-ST “twist lock”
Combo Module
The DFG380XX is a combo 6 port module of RJ-45’s at
10/100Mbps and fiber optic ports at 100MB.
The Combo module is equipped with dual mode
ST-type connectors and dual speed copper ports.
The ST-connector functions as a fiber optic
transceiver to support 100BASE-FX network
segments. When installed in a
DFG48000 Managed Switch, the copper port
supports the standard distance 100m
on each port and the fiber port supports
fiber optic cable distances up the IEEE-standard
100Mbps distance limits, i.e., typically 2km at
Full-duplex and 412m at half-duplex. Each port has an Activity
(ACT) LED indicating packets being received, a
Link (LK) LED that indicates proper connectivity
with the remote device when lit, and
FDX/HDX LED to indicate full-duplex mode
when lit (or half-duplex when off).
The 10/100 LED indicates the speed,
if the LED is ON 100Mbps if it is OFF 10Mbps.