GPON Optical Levels

Florian Lohoff f at
Tue Oct 13 13:06:53 UTC 2015

On Mon, Oct 12, 2015 at 10:46:59PM +0200, Baldur Norddahl wrote:
> Here is a small secret: If you attenuate the PON port so the signal level
> at the OLT is as low as possible, your network will be more robust against
> people connecting P2P fiber media converters to your network. This is
> because these devices typically have TX power that is significantly less
> than your ONUs. By attenuate the signal you can bring the rogue signal
> below the detection threshold of the OLT.
> In my experience one way to do this is to always use 1:128 splits. Even if
> you are only going to connect less than 32 ONUs, you will find that 1:128
> can be more robust. In fact I discovered this little trick after we started
> using 1:128 splits (for flexibility, not because we actually connect that
> many clients). Because the fiber plant is shared with other service

Wouldnt a 1:32 splitter + a 9dB attenuation be the same? From
the price/performance the 1:128 splitter should be much more expensive.

We have seen happening the same converting a former p2p footprint to
GPON and somebody got a left over p2p device connected. But this was
a single incident so far.

Florian Lohoff                                                 f at
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