SYSTEMS AND METHODS FOR SUPPORTING PHASE ADJUSTMENTS OVER DOCSIS
A method for adjusting a phase error includes a first device detecting a phase error at a timing interface of the first device. The first device modifying a DOCSIS timing protocol parameter based upon the detected phase error. The first device causing a modification of a second device's timestamp output in a manner based upon the detected phase error by the modification of the DOCSIS timing protocol parameter.
1 . A method for adjusting a phase error comprising:
(a) a first device detecting a phase error at a timing interface of the first device;
(b) the first device modifying a DOCSIS timing protocol parameter based upon the detected phase error;
(c) the first device causing a modification of a second device's timestamp output in a manner based upon the detected phase error by the modification of the DOCSIS timing protocol parameter.
2 . The method of claim 1 wherein the first device is a CMTS.
3 . The method of claim 1 wherein the second device is a cable modem.
4 . The method of claim 1 wherein the first device includes one or more devices in an R-PHY architecture.
5 . The method of claim 1 wherein the DOCSIS timing protocol parameter is decreased over time after the modification.
6 . The method of claim 5 wherein a DOCSIS timestamp is modified over time as the DOCSIS timing protocol parameter is modified in an opposing direction.
7 . The method of claim 1 wherein the phase error is detected at an ingress precision time protocol interface of the first device.
8 . The method of claim 6 wherein the DOCSIS timestamp is modified at a rate within a range specified by a corresponding DOCSIS protocol.
9 . The method of claim 1 wherein said timing interface is a precision timing protocol interface.
10 . The method of claim 1 wherein the DOCSIS timing protocol parameter is t-cm-adj.
11 . The method of claim 1 wherein the second device's timestamp output is a precision time protocol clock timestamp output.
12 . The method of claim 1 wherein the first device includes a R-MACPHY device.
13 . The method of claim 1 wherein the first device includes a RPD device.
14 . A method for adjusting a phase error comprising:
(a) a first device detecting a phase error at a first interface of the first device;
(b) the first device modifying a DOCSIS timing protocol parameter based upon the detected phase error;
(c) modifying of a second device's timestamp output based upon the modification of the DOCSIS timing protocol parameter.