Mirrored passive optical access network

摘要

A passive optical access network comprises a first optical line terminal (OLT) connected to a remote network node, e.g. an optical network unit (ONU) or a third optical line terminal (OLT), via a first optical channel. A second optical line terminal (OLT) is connected to the remote network node via a second optical channel. Data packets communicated downstream by the first OLT are received at the network node and the data packets are then communicated upstream to the second OLT. Thus, the two OLTs can exchange messages by using the protection links of the passive optical network (PON) architecture in the place of, or in addition to, other core links that the terminals might have.