A method for providing enhanced features in a Gigabit-capable Passive Optical Network, GPON, that comprises an enhanced Optical Line Termination, OLT, and a plurality of Optical Network Units, ONUs, the plurality of ONUs further comprising enhanced ONUs and legacy ONUs, wherein the enhanced OLT communicates with the plurality of ONUs via downstream frames and upstream bursts, each of the downstream frames and upstream bursts being compliant with GPON standards, the method comprising the steps of: transmitting from the enhanced OLT the downstream frames to the plurality of ONUs, the downstream frames including downstream sub-frames with at least one of the downstream sub-frames being an overhead sub-frame that includes information of the enhanced features, wherein each of the downstream sub-frames includes a downstream identifier field that indicates to the plurality of ONUs whether the downstream sub-frame is the overhead sub-frame, wherein the overhead sub-frame is a GPON encapsulation method, GEM, frame and the downstream identifier field of the overhead subframe contains a port ID having a designated value which is recognizable by the enhanced ONUs and not by the legacy ONUs, such that the overhead sub-frame is recognizable by the enhanced ONUs and transparent to the legacy ONUs; receiving by the enhanced OLT the upstream bursts from the plurality of ONUs, the upstream bursts including upstream sub-frames, each of the upstream sub-frames including an upstream identifier field that indicates to the enhanced OLT whether the upstream sub-frame is the overhead sub-frame, wherein the upstream identifier field of the overhead subframe contains a port ID having a designated value which is recognizable by the enhanced ONUs and not by the legacy ONUs; and performing network operations by the enhanced OLT and the enhanced ONUs to provide the enhanced features specified in the overhead sub-frame. transmitting from the enhanced OLT the downstream frames to the plurality of ONUs, the downstream frames including downstream sub-frames with at least one of the downstream sub-frames being an overhead sub-frame that includes information of the enhanced features, wherein each of the downstream sub-frames includes a downstream identifier field that indicates to the plurality of ONUs whether the downstream sub-frame is the overhead sub-frame, wherein the overhead sub-frame is a GPON encapsulation method, GEM, frame and the downstream identifier field of the overhead subframe contains a port ID having a designated value which is recognizable by the enhanced ONUs and not by the legacy ONUs, such that the overhead sub-frame is recognizable by the enhanced ONUs and transparent to the legacy ONUs; receiving by the enhanced OLT the upstream bursts from the plurality of ONUs, the upstream bursts including upstream sub-frames, each of the upstream sub-frames including an upstream identifier field that indicates to the enhanced OLT whether the upstream sub-frame is the overhead sub-frame, wherein the upstream identifier field of the overhead subframe contains a port ID having a designated value which is recognizable by the enhanced ONUs and not by the legacy ONUs; and performing network operations by the enhanced OLT and the enhanced ONUs to provide the enhanced features specified in the overhead sub-frame.