Method and apparatus for mapping and de-mapping in an optical transport network
The embodiments of the present invention disclose methods and apparatuses for mapping processing and de-mapping processing in an optical transport network. A Lower Order Optical Channel Data Unit (LO ODU) signal is mapped into a payload area of an Optical Channel Data Tributary (ODTU) signal in units of M bytes. 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. Overhead information is encapsulated to an overhead area of the ODTU signal. Thereafter, the ODTU signal is multiplexed into the HO OPU. In this way, an efficient and universal mode for mapping the LO ODU to the HO OPU is provided.
1. A method for processing data in an Optical Transport Network (OTN), comprising:
mapping, by a processor of an apparatus for processing data, 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 time 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;
encapsulating overhead information to an overhead area of the ODTU signal; and
multiplexing the ODTU signal into the HO OPU.
2. The method according to claim 1 , wherein the overhead information comprises information indicating a quantity of M-byte data groups of the LO ODU signal that are mapped during a multi-frame period.
3. The method according to claim 2 , wherein the overhead information further comprises clock information that is determined according to the quantity of M-byte data groups.
4. The method according to claim 1 , wherein the overhead information is presented in a tributary slot overhead area corresponding to the first tributary slot or the last tributary slot among tributary slots that are occupied by the ODTU signal.
5. An apparatus for processing data in an Optical Transport Network (OTN), 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 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; and
multiplex the ODTU signal into the HO OPU.
6. The apparatus according to claim 5 , wherein the overhead information comprises information indicating a quantity of M-byte data groups of the LO ODU signal that are mapped during a multi-frame period.
7. The apparatus according to claim 6 , wherein the overhead information further comprises clock information that is determined according to the quantity of M-byte data groups.
8. The apparatus according to claim 5 , wherein the overhead information is presented in a tributary slot overhead area corresponding to the first tributary slot or the last tributary slot among tributary slots that are occupied by the ODTU signal.
9. A method for processing data in an Optical Transport Network (OTN), comprising:
parsing, by a processor in an apparatus for processing data, a Higher Order Optical Channel Payload Unit (HO OPU) to obtain an Optical Channel Data Tributary Unit (ODTU) signal; and
de-mapping a Lower Order Optical Channel Data Unit (LO ODU) signal from a payload area of the ODTU signal in groups of M bytes, wherein M is equal to the number of tributary slots of the HO OPU that are occupied by the ODTU, and M is an integer larger than 1.
10. The method according to claim 9 , wherein de-mapping the LO ODU signal comprises:
acquiring, from an overhead area of the ODTU, overhead information indicating a quantity of M-byte data groups of the LO ODU signal that have been mapped into the payload area of the ODTU; and
de-mapping the LO ODU signal from the payload area of the ODTU signal in the groups of M bytes according to the quantity of M-byte data groups.
11. The method according to claim 10 , wherein the overhead information is presented in a tributary slot overhead area corresponding to the first tributary slot or the last tributary slot among tributary slots that are occupied by the ODTU signal.
12. An apparatus for processing data in an Optical Transport Network (OTN), 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:
parse a Higher Order Optical Channel Payload Unit (HO OPU) to obtain an Optical Channel Data Tributary Unit (ODTU) signal; and
de-map a Lower Order Optical Channel Data Unit (LO ODU) signal from a payload area of the ODTU signal in groups of M bytes, wherein M is equal to the number of tributary slots of the HO OPU that are occupied by the ODTU, and M is an integer larger than 1.
13. The apparatus according to claim 12 , wherein the instructions to de-map the LO ODU signal include instructions to:
acquire, from an overhead area of the ODTU, overhead information indicating a quantity of M-byte data groups of the LO ODU signal that have been mapped into the payload area of the ODTU; and
de-map the LO ODU signal from the payload area of the ODTU signal in the units groups of M bytes according to the quantity of M-byte data groups.
14. The apparatus according to claim 13 , wherein the overhead information is presented in a tributary slot overhead area corresponding to the first tributary slot or the last tributary slot among tributary slots that are occupied by the ODTU signal.