Installation Instructions

in dB, to cover all effects. Margin is life and design dependent, but is typically 3.5 to 4.5 dB,
minimum. Whether you require additional margin depends on the details, such as whether actual or
specified transmitter power and receiver sensitivity are used. Extreme Networks specifications
represent worst-case values.
The sum of margin, dispersion power penalty, and passive cable plant losses must be less than the
available power budget. Alternatively, if you calculate available power margin as the difference
between the available budget and the sum of losses and dispersion, the margin can be more or less
than required, which determines whether additional consideration is needed. If the power budget is
exceeded or margin is insufficient, you can either use a transceiver rated for longer distance
operation, or calculate budget and losses using actual values rather than specified limit values.
Either method can improve the link budget by 4 to 5 dB or more.
Optical routing design
May 2018 Installing Transceivers and Optical Components on VOSS 22