The OLT duplex feed method relies on two separate GPON feeds from the OLT. Each of these feeds can take a diverse route to the customer splitter distribution location (Distribution Point).
The traditional 1x32 Splitter is replaced by a 2x32 splitter and each input is fed with a separate OLT feed.
This provides fallback should one OLT feed become damaged, enabling a software switch on the OLT to a separate line card enabling uninterrupted data transmission.
The major benefit with this method is that the ONT and customer drop can remain as standard items and ensure that costs are not too high.
Full Duplex Redundancy
Full duplex redundancy requires two separate distribution nodes, coupled with two separate customer drops.
This method provides a very effective redundancy method, however the most costly element of GPON deployment needs to be duplicated (The last Mile)..
A second disadvantage is the requirement for a Dual input ONT, a more costly product for the customer premises.
Full Duplex Redundancy, with dual Chassis OLT
It is possible to add a second OLT at the head end.
This method of resiliance will provide the ultimate in redundancy but is essentially the operator will be duplicating the GPON feed. So the customer will receive two separate GPON circuits which can be fed into a Dual input ONT.
