Method and apparatus for link sharing among multiple epons
View Patent ↗One embodiment of the present invention provides an optical line terminal (OLT) in an Ethernet passive optical network (EPON). The OLT includes a number of bi-direction optical transceivers. At least one bi-direction optical transceiver is coupled to an optical network unit (ONU) group that includes a number of ONUs. The OLT further includes a first downstream media access control (MAC) interface configured to provide a first downstream control signal and a splitter configured to split the first downstream control signal to a number of sub-signals. At least one sub-signal is configured to control downstream transmission of a corresponding bi-direction optical transceiver to a corresponding ONU-group.
1. An optical line terminal (OLT) in an Ethernet passive optical network (EPON), comprising:
a plurality of optical transceivers, wherein an optical transceiver from among the plurality of optical transceivers is coupled to a corresponding optical network unit (ONU) group from among a plurality of ONU groups and configured to transmit a first downstream signal to the corresponding ONU group;
a first downstream media access control (MAC) interface configured to provide a downstream control signal;
an optical transmitter coupled to the corresponding ONU group, the optical transmitter being configured to transmit a second downstream signal to the corresponding ONU group;
a second downstream MAC interface configured to control transmission of the second downstream signal; and
a splitter configured to split the downstream control signal into a plurality of sub-signals, wherein a sub-signal from among the plurality of sub-signals controls the transmission of the first downstream signal.
2. The OLT of claim 1 , further comprising:
a plurality of individual upstream MAC interfaces, wherein an individual upstream MAC interface from among the plurality of individual upstream MAC interfaces is configured to communicate with the corresponding ONU group.
3. The OLT of claim 2 , wherein the individual upstream MAC interface is further configured to arbitrate upstream transmissions from the plurality of ONU groups.
4. The OLT of claim 2 , wherein the plurality of individual upstream MAC interfaces are configured to separately arbitrate upstream transmissions from different ONU groups to facilitate concurrent upstream transmission to the OLT.
5. The OLT of claim 2 , wherein the plurality of individual upstream MAC interfaces are configured to allocate discovery slots to respective ONU groups, and wherein the discovery slots are substantially aligned in time.
6. The OLT of claim 3 , wherein the downstream and upstream transmissions propagate on two different wavelengths.
7. The OLT of claim 2 , wherein the first downstream MAC interface and the individual upstream MAC interface are configured to operate at different data rates.
8. The OLT of claim 2 , wherein the first downstream MAC interface and the individual upstream MAC interface are configured to operate at an identical data rate.
9. The OLT of claim 2 , further comprising:
a shared upstream MAC interface configured to interface with the plurality of ONU groups.
10. The OLT of claim 9 , farther comprising:
a merger configured to:
merge upstream transmissions from the plurality of ONU groups into a merged transmission; and
send the merged transmission to the shared upstream MAC interface.
11. The OLT of claim 9 , wherein upstream transmissions to the individual upstream MAC interface and to the shared upstream MAC interface propagate on different wavelengths.
12. The OLT of claim 1 , wherein the first downstream signal and the second downstream signal are coupled to an optical fiber via a wavelength division multiplexing (WDM) coupler.
13. An optical line terminal (OLT) in an Ethernet passive optical network (EPON), comprising:
a plurality of optical transceivers configured to transmit a first downstream signal to a corresponding optical networking unit (ONU) group from among a plurality of ONU groups; and
a plurality of optical transmitters configured to transmit a second downstream signal to the corresponding ONU group,
wherein the plurality of optical transceivers are further configured to be controlled by a common media access control (MAC) interface, and
wherein the plurality of optical transmitters are further configured to be controlled by a plurality of MAC interfaces.
14. The OLT of claim 13 , wherein each of the plurality of optical transmitters are further configured to be dedicated to a separate ONU group from among the plurality of ONU groups.
15. The OLT of claim 13 , wherein the plurality of optical transceivers are further configured to transmit identical downstream signals as a single downstream link shared among the plurality of ONU groups.
16. The OLT of claim 13 , further comprising:
a plurality of upstream MAC interfaces configured to arbitrate concurrent upstream transmissions from the plurality of ONU groups.
17. The OLT of claim 16 , wherein the downstream signal and the concurrent upstream transmissions propagate on different wavelengths.
18. The OLT of claim 13 , wherein the common MAC interface and the plurality of MAC interfaces are configured to operate at an identical data rate.
19. The OLT of claim 13 , wherein the common MAC interface and the plurality of MAC interfaces are configured to operate at different data rates.
20. An optical line terminal (OLT) in an Ethernet passive optical network (EPON), comprising:
a plurality of optical transceivers configured to receive a first and a second upstream signal from a corresponding optical networking unit (ONU) group from among a plurality of ONU groups;
a merger configured to receive and merge first upstream signals received by the plurality of optical transceivers into a merged upstream transmission;
a common media access control (MAC) interface configured to arbitrate the first upstream signals within the merged upstream transmission; and
a plurality of MAC interfaces configured to process second upstream signals received by the plurality of optical transceivers.
21. The OLT of claim 20 , further comprising:
a plurality of optical transmitters, wherein each optical transmitter from among the plurality of optical transmitters is configured to be dedicated to separate ONU groups from among the plurality of ONU groups.
22. The OLT of claim 20 , wherein the plurality of optical transceivers are further configured to transmit identical downstream signals on a downstream link shared among the plurality of ONU groups.
23. The OLT of claim 20 , wherein the plurality of MAC interfaces are further configured to arbitrate concurrent upstream transmissions received from the plurality of ONU groups.
24. The OLT of claim 23 , wherein downstream signals and the concurrent upstream transmissions propagate on different wavelengths.
25. The OLT of claim 20 , wherein the common MAC interface and the plurality of MAC interfaces are configured to operate at an identical data rate.
26. The OLT of claim 20 , wherein the common MAC interface and the plurality of MAC interfaces are configured to operate at different data rates.