Delivering CPRI and ethernet signals over optical networks

An apparatus for communication, comprising:

• a first communication interface, which is configured to:
• receive input frames, which comprise data symbols that were derived by encoding respective characters, and further comprise one or more synchronization symbols distinguishable from the data symbols,
• recover the characters from the data symbols,
• map the characters into Optical Transport Network (OTN) communication frames and discard the synchronization symbols, and transmit the OTN communication frames carrying the mapped characters, wherein the mapping is performed using a Bit-synchronous Mapping Procedure (BMP), while filling some locations in the OTN frames with stuffing characters, so that the rate of the first characters matches a desired rate of the OTN communication frames, wherein a protocol for delivering the characters in the OTN communication frames supports a mapping scheme in which the characters are delivered at a first data rate, and wherein the first communication interface is configured to map the characters so as to deliver the characters at a second data rate that is lower than the first data rate;
• and
• a second communication interface, which is configured to:
• receive the communication frames from the first communication interface, extract the characters from the communication frames by synchronizing to the mapped input frames independently of the synchronization symbols, and
• reconstruct the input frames to produce reconstructed input frames, including the data symbols and the synchronization symbols, by re-encoding the extracted characters.

A method for communication, comprising:

• receiving in a first communication interface input frames, which comprise data symbols that were derived by encoding respective first characters, and further comprise one or more synchronization symbols distinguishable from the data symbols;
• receiving in the first communication interface Ethernet frames that encapsulate second characters;
• recovering the first characters from the data symbols and recovering the second characters from the Ethernet frames;
• mapping the first characters into Optical Transport Network (OTN) communication frames and discarding the synchronization symbols, wherein the mapping is performed using a Bit-synchronous Mapping Procedure (BMP), while leaving locations in the OTN frames empty from carrying first characters, so that the rate of the first characters matches a desired rate of the OTN communication frames;
• mapping the second characters into at least some of the locations in the OTN communication frames that carry no first characters;
• transmitting the OTN communication frames carrying the mapped first characters and the mapped second characters, to a second communication interface;
• extracting the first and second characters from the communication frames in the second communication interface by synchronizing to the input frames independently of the synchronization symbols;
• and
• reconstructing the input frames in the second communication interface, including the data symbols and the synchronization symbols, by re-encoding the extracted first characters, and further reconstructing in the second communication interface the Ethernet frames by re-encapsulating the extracted second characters into the Ethernet frames.

An apparatus for communication, comprising:

• a first communication interface, which is configured to:
• receive input frames, which comprise data symbols that were derived by encoding respective first characters, and further comprise one or more synchronization symbols distinguishable from the data symbols,
• receive Ethernet frames that encapsulate second characters,
• recover the first characters from the data symbols and recover the second characters from the Ethernet frames,
• map the first characters into Optical Transport Network (OTN) communication frames and discard the synchronization symbols, wherein the mapping is performed using a Bit-synchronous Mapping Procedure (BMP), while leaving locations in the OTN communication frames empty from carrying first characters, so that the rate of the first characters matches a desired rate of the OTN frames,
• map the second characters into at least some of the locations in the OTN frames that carry no first characters, and
• transmit the OTN communication frames carrying the mapped first characters and the mapped second characters;
• and
• a second communication interface, which is configured to:
• receive the OTN communication frames from the first communication interface,
• extract the first and second characters from the communication frames by synchronizing to the input frames independently of the synchronization symbols, and
• reconstruct the input frames in the second communication interface, including the data symbols and the synchronization symbols, by re-encoding the extracted first characters, and further reconstruct the Ethernet frames by re-encapsulating the extracted second characters into the Ethernet frames.