Providing access to client overhead while transparently transmitting the client signal over multiple optical subcarriers

A method performed in a network including at least a first node, a second node, and a third node, the method comprising:

• receiving, by the first node, client data that includes a client overhead section and a payload section;
• copying data, as virtual overhead data, from the client overhead section;
• encapsulating the client data in a frame that includes a frame overhead section and a frame payload section, the client data being encapsulated in the frame payload section;
• storing the virtual overhead in the frame;
• generating a plurality of optical subcarriers, one of which carrying information indicative of the frame;
• transmitting the plurality of optical subcarriers to the second node;
• detecting at least said one of the plurality of optical subcarriers at the second node;
• extracting the virtual overhead data from the frame;
• recovering the client overhead data from the extracted virtual overhead data;
• recovering the client data from the frame;
• replacing the data in the client overhead section of the client data with the recovered client overhead data;
• and
• outputting the client data with the recovered client overhead data.