Methods, systems, and apparatus for hosting an optical line terminal (OLT) bonding engine are disclosed. In one aspect, packet data for transmission over a passive optical (PON) is selected. A transmission wavelength assigned to the packet data is identified. A particular OLT is selected from among the additional OLTs to transmit the packet data over the PON based on the corresponding wavelength of the particular OLT matching the identified transmission wavelength assigned to the packet. The packet data is formatted based on the particular OLT. The formatted packet data is transmitted to the particular OLT for transmission over the communications interface.