Hitless, multi-rate optical transmission and reception

A method for use in an optical communication device, comprising:

• encoding a first portion of a data sequence according to a first modulation format that provides a first transmission data rate;
• generating rate change signaling information to indicate a rate change from the first transmission data rate to a second transmission data rate different from the first transmission data rate, wherein the second transmission data rate is provided by a second modulation format different from the first modulation format;
• encoding a rate change signaling portion into the data sequence at a pre-determined number of data blocks prior to the rate change from the first transmission data rate to the second, transmission data rate, Wherein the rate change signaling portion comprises the rate change signaling information;
• encoding a second portion of the data sequence in a third modulation format to provide a continuous data transmission during the rate change;
• encoding a third portion of the data sequence according to the second modulation format;
• generating an optical signal based on the first portion, the rate change signaling portion, the second portion, and the third portion;
• and
• transmitting the generated optical signal towards an optical receiver via an optical network.

A method comprising:

• encoding a data sequence in a plurality of modulation formats to produce a multi-rate data stream, wherein a first of the modulation formats provides a first transmission data rate, and wherein a second of the modulation formats provides a second transmission data rate different from the first transmission data rate;
• generating rate change signaling information to indicate a rate change from the first transmission data rate to a second transmission data rate different from the first transmission data rate, wherein the second transmission data rate is provided by a second modulation format different from the first modulation format;
• encoding a rate change signal block into the multi-rate data stream at a predetermined number of data blocks prior to the rate change, wherein the rate change signaling block comprising the rate change signaling information;
• converting the multi-rate data stream into an optical signal;
• and
• transmitting the converted optical signal towards a remote optical receiver via an optical network.