System and method for performing power management without losing data, connectivity or reachability
View Patent ↗A system and method for performing power management in a communication system without losing data is disclosed. The G.Lite system is an exemplary system suitable for implementing the present invention because it includes at least one operational state and an idle state in which no data is transmitted. The G.Lite standard defines ATU states. The defined states are full on state L0, low power state L1 and idle state L3. In L0 state, the ADSL link is fully operational at full data rate. In L1 state, the ADSL link is fully operational at a lower data rate. In L3 state, no signal is transmitted. Because no signal is transmitted, no idle cells are transmitted. This will result in losing the cell delineation and ATM link connectivity. Therefore, when data is received for an ATU in L3 state, data cells may be lost. The present invention solves the problem of lost data cells by allowing interaction between the control path and the data path by requesting that the micro-controller be interrupted when a data cell arrives for an ATU-C that is in L3 state. When a data cell arrives for an ATU-C in L3 state, the micro-controller is interrupted. The micro-controller then ensures that a sufficient number of idle cells are sent to the ATU-C prior to any data cells being sent to the ATU-C.
1. A communications system that provides for power management, comprising:
a terminal unit that includes an operational state that supports a data communication and an idle state that does not support the data communication;
a micro-controller configured to transition the terminal unit from the operational state to the idle state; and
the micro-controller being further configured to request a communications sublayer entity to interrupt the micro-controller upon receiving a data cell destined for the terminal unit after transitioning the terminal unit from the operational state to the idle state.
2. The communications system of claim 1 , wherein the micro-controller is further configured to request the communications sublayer entity to buffer the data cell and any one of a number of subsequent data cells destined for the terminal unit received after transitioning the terminal unit from the operational state to the idle state.
3. The communications system of claim 1 , wherein the micro-controller is further configured to transition the terminal unit from the idle state to the operating state upon being interrupted by the communications sublayer entity.
4. The communications system of claim 1 , wherein the micro-controller is further configured to cause a number of idle cells to be applied to the terminal unit for transmission by the terminal unit for data communications synchronization during the transition from the idle state to the operational state.
5. A communications system that provides for power management, comprising:
a terminal unit that includes an operational state that supports a data communication and an idle state that does not support the data communication;
transition means for transitioning the terminal unit from the operational state to the idle state; and
interrupt means for requesting a communications sublayer entity to interrupt the transition means upon receiving a data cell destined for the terminal unit after transitioning the terminal unit from the operational state to the idle state.
6. The communications system of claim 5 , wherein the interrupt means further comprises means for requesting the communications sublayer entity to buffer the data cell and any one of a number of subsequent data cells destined for the terminal unit received after transitioning the terminal unit from the operational state to the idle state.
7. The communications system of claim 5 , further comprising means for transitioning the terminal unit from the idle state to the operating state upon being interrupted by the communications sublayer entity.
8. The communications system of claim 5 , further comprising means for applying a number of idle cells to be applied to the terminal unit for transmission by the terminal unit for data communications synchronization during the transition from the idle state to the operational state.
9. A data communications method that provides for power management, comprising:
providing a terminal unit with an operational state that supports a data communication and an idle state that does not support the data communication;
transitioning the terminal unit from the operating state to the idle state during a period of inactivity; and
requesting a communications sublayer entity to generate an interrupt upon receiving a data cell destined for the terminal unit after transitioning the terminal unit from the operational state to the idle state.
10. The data communications method of claim 9 , further comprising requesting the communications sublayer entity to buffer the data cell and any one of a number of subsequent data cells destined for the terminal unit received after transitioning the terminal unit from the operational state to the idle state.
11. The data communications method of claim 9 , further comprising transitioning the terminal unit from the idle state to the operating state when the communications sublayer provides the interrupt.
12. The data communications method of claim 11 , further comprising applying a number of idle cells to the terminal unit to provide for a data communications synchronization.