Method and apparatus for mapping and de-mapping in an optical transport network

1. A apparatus for processing data in an optical transport network (OTN), the apparatus comprising:

a processor and a computer readable non-transitory medium having a plurality of computer executable instructions stored thereon which, when executed by the processor, cause the processor to:

map a low order optical channel data unit (LO ODU) signal into a payload area of an optical channel data tributary unit (ODTU) signal, wherein a group of M bytes of the LO ODU signal are mapped into a group of M bytes of the payload area of the ODTU signal, wherein M is an integer greater than 1;

multiplex the ODTU signal into a high order optical channel payload unit (HO OPU);

map the HO OPU into a high order optical channel data unit (HO ODU);

map the HO ODU into a high order optical channel transport unit (HO OTU) signal; and

send the HO OTU signal.

2. The apparatus according to claim 1 , wherein mapping the LO ODU signal into the payload area of the ODTU signal is performed under control of a generic mapping procedure (GMP) mapping mechanism.

3. The apparatus according to claim 1 , wherein the ODTU signal carries overhead information in an overhead area of the ODTU signal, the overhead information comprises information indicating a number of M-byte data groups of the LO ODU signal that are mapped during a multi-frame period.

4. The apparatus according to claim 3 , wherein the overhead information further comprises clock information that is determined according to the number of the M-byte data groups.

5. The apparatus according to claim 1 , wherein the ODTU signal carries overhead information in an overhead area of the ODTU signal, the overhead information is presented in an overhead area associated with a first tributary slot or a last tributary slot among tributary slots that are occupied by the ODTU signal.

6. The apparatus according to claim 1 , wherein when mapping the LO ODU signal into the payload area of the ODTU signal and into data groups of M bytes, the processor is configured to:

map a group of M successive LO ODU bytes into a group of M successive ODTU bytes.

7. An apparatus for processing data in an optical transport network (OTN), the apparatus comprising:

a processor and a computer readable non-transitory medium having a plurality of computer executable instructions stored thereon that, when executed by the processor, cause the processor to:

map a low order optical channel data unit (LO ODU) signal into a payload area of an optical channel data tributary unit (ODTU) signal organized into data groups of M bytes, wherein M is an integer greater than 1 and is equal to a number of tributary slots of a high order optical channel payload unit (HO OPU) that are to be occupied by the ODTU signal; and

multiplex the ODTU signal into the HO OPU.

8. The apparatus according to claim 7 , wherein mapping the LO ODU signal into the payload area of the ODTU signal is performed under control of a generic mapping procedure (GMP) mapping mechanism.

9. The apparatus according to claim 7 , wherein the ODTU signal carries overhead information in an overhead area of the ODTU signal, the overhead information comprises information indicating a number of the M-byte data groups of the LO ODU signal that are mapped during a multi-frame period.

10. The apparatus according to claim 9 , wherein the overhead information further comprises clock information that is determined according to the number of the M-byte data groups.

11. The apparatus according to claim 7 , wherein the ODTU signal carries overhead information in an overhead area of the ODTU signal, the overhead information is presented in an overhead area associated with a first tributary slot or a last tributary slot among tributary slots that are occupied by the ODTU signal.

12. The apparatus according to claim 7 , wherein when mapping the LO ODU signal into the payload area of the ODTU signal and into the data groups of M bytes, the processor is configured to:

map a group of M successive LO ODU bytes into a group of M successive ODTU bytes.

13. A method for processing data in an optical transport network (OTN), the method comprising:

mapping a low order optical channel data unit (LO ODU) signal into a payload area of an optical channel data tributary unit (ODTU) signal that includes an overhead area for carrying overhead information, wherein a group of M LO ODU signal bytes is mapped into a group of M ODTU signal bytes, and M is an integer greater than 1;

multiplexing the ODTU signal into a high order optical channel payload unit (HO OPU);

mapping the HO OPU into a high order optical channel data unit (HO ODU);

mapping the HO ODU into a high order optical channel transport unit (HO OTU) signal; and

sending the HO OTU signal.

14. The method according to claim 13 , wherein mapping the LO ODU signal into the payload area of the ODTU signal is performed under control of a generic mapping procedure (GMP) mapping mechanism.

15. The method according to claim 13 , wherein the overhead information comprises information indicating a number of M-byte data groups of the LO ODU signal that are mapped during a multi-frame period.

16. The method according to claim 15 , wherein the overhead information further comprises clock information that is determined according to the number of the M-byte data groups.

17. The method according to claim 13 , wherein the overhead information is presented in an overhead area associated with a first tributary slot or a last tributary slot among tributary slots that are occupied by the ODTU signal.

18. The method according to claim 13 , wherein mapping the LO ODU signal into the payload area of the ODTU signal and into data groups of M bytes comprises:

mapping a group of M successive LO ODU bytes into a group of M successive ODTU bytes.

19. A system for processing data in an optical transport network (OTN) comprising a first optical network apparatus and a second optical network apparatus, wherein

the first optical network apparatus comprises a first processor and a first computer readable non-transitory medium having a plurality of computer executable instructions stored thereon which, when executed by the first processor, cause the first processor to:

map a lower order optical channel data unit (LO ODU) signal into a payload area of an optical channel data tributary unit (ODTU) signal in groups of M bytes, wherein M is equal to the number of tributary slots of a higher order optical channel payload unit (HO OPU) that are to be occupied by the ODTU signal, and M is an integer larger than 1;

encapsulate overhead information to an overhead area of the ODTU signal;

multiplex the ODTU signal into the HO OPU;

map the HO OPU into a high order optical channel data unit (HO ODU);

map the HO ODU into a high order optical channel transport unit (HO OTU) signal; and

the first network apparatus further comprises a transmitting interface for sending the HO OTU signal to an optical transmission medium; and

the second optical network apparatus comprises a receiving interface for receiving the HO OTU signal from the optical transmission medium, the receiving interface comprises a second processor and a second computer readable non-transitory medium having a plurality of computer executable instructions stored thereon which, when executed by the second processor, cause the second processor to:

parse the HO OPU in the HO OTU to determine the ODTU and the value of M, wherein M equals the amount of time slots occupied by the ODTU; and

de-map the LO ODU from the payload area of the ODTU in an M-byte granularity.

20. The system according to claim 19 , wherein the ODTU signal carries overhead information in an overhead area of the ODTU signal, the overhead information is only presented in a last tributary slot among tributary slots that are occupied by the ODTU signal.