METHOD OF SAVING POWER IN OPTICAL ACCESS NETWORK

• US 20100260497A1
• Filed: 05/22/2008
• Published: 10/14/2010
• Est. Priority Date: 10/23/2007
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Kim, Sung-Chang, Kim, Geun-Yong, Yoon, Bin-Yeong
• Granted Patent: US 8,346,082 B2
• Time in Patent Office: Days
• US Class Current: 398/38
• CPC Class Codes: H04B 10/272 Star-type networks or tree-type networks
• CPC Class Codes: H04Q 11/0067 Provisions for optical access or distribution networks, e.g. Gigabit Ethernet Passive Optical Network (GE-PON), ATM-based Passive Optical Network (A-PON), PON-Ring
• CPC Class Codes: H04Q 2011/0079 Operation or maintenance aspects

Abstract

Provided is a method of reducing power consumption of an optical access network (OAN) as much as possible by configuring an optical line terminal (OLT) and optical network terminals (ONTs) in the OAN to support a maximum power-saving mode. According to the method, upon the application of power, an ONT operates normally in an activation mode. The ONT then determines whether the requirements for switching from activation mode to power-saving mode are satisfied. If the requirements are satisfied, the ONT transmits a sleep signal to an OLT, which is a message notifying that the ONT will soon switch to power-saving mode. Thereafter, the ONT switches to power-saving mode and cuts off power for all functions except for power for monitoring and controlling external inputs. The ONT then determines whether the requirements for switching from power-saving mode to activation mode are satisfied. If the requirements are satisfied, the ONT transmits a wake-up signal to the OLT and switches to the activation mode for normal operation.

Claims

1. A method of reducing power consumption for an optical network terminal (ONT) in an optical access network (OAN), the method comprising:

applying power so that the ONT operates normally in an activation mode;

determining whether requirements needed for the ONT to switch from the activation mode to power-saving mode are satisfied;

transmitting, if the requirements for switching from the activation mode to the power-saving mode are satisfied, a sleep signal, as a message notifying that the ONT will soon switch to the power-saving mode, from the ONT to an optical line terminal (OLT);

switching the ONT to the power-saving mode and cutting off power for all functions of the ONT except for power for monitoring and controlling an external input;

determining whether requirements needed for the ONT to switch from the power-saving mode to the activation mode are satisfied; and

transmitting, if the requirements for switching from the power-saving mode to the activation mode are satisfied, a wake-up signal from the ONT to the OLT and switching the ONT to the activation mode for normal operation.

2. The method of claim 1, wherein the requirements for switching from the activation mode to the power-saving mode are that the OLT or terminals connected to the ONT are into a state in which all of the terminals connected to the ONT do not operate normally, a state in which the OLT has no packets to transmit to a terminal connected to the ONT while at least one of the terminals connected to the ONT is in a power-saving mode and the remaining terminals malfunction, or a state in which the OLT cannot operate normally due to a link failure while at least one of the terminals connected to the ONT is in the power-saving mode and the remaining user terminals malfunction.

3. The method of claim 1, wherein the requirements for switching from the power-saving mode to the activation mode are that the OLT or terminals connected to the ONT are into a state in which at least one of the terminals connected to the ONT is in an activation mode or a state in which the OLT has packets to transmit to a terminal connected to the ONT while at least one of the terminals connected to the ONT is in the power-saving mode and the remaining terminals malfunction.

4. A method of reducing power consumption for an optical line terminal (OLT) in an optical access network (OAN), the method comprising:

applying power so that the OLT operates normally in an activation mode;

determining whether requirements needed for the OLT to switch from the activation mode to power-saving mode are satisfied;

switching, if the requirements for switching from the activation mode to the power-saving mode are satisfied, the OLT to the power-saving mode and turning off power for all functions except for power for monitoring and controlling upstream and downstream interfaces;

determining whether requirements needed for the OLT to switch from the power-saving mode to the activation mode are satisfied; and

applying, if the requirements for switching from the power-saving mode to the activation mode are satisfied, the power from the OLT so that the OLT operates normally in the activation mode.

5. The method of claim 4, wherein the requirements for switching from the activation mode to the power-saving mode are that an uplink or optical network terminals (ONTs) connected to the OLT are into a state in which the uplink cannot operate normally due to a failure, a state in which at least one of the ONTs connected to the OLT is in a power-saving mode and the remaining ONTs malfunction while the uplink has no packets to transmit to the ONT connected to the OLT, or a state in which all the ONTs cannot operate normally due to a failure while the uplink has no packets to transmit to the ONT connected to the OLT.

6. The method of claim 4, wherein the requirements for switching from the power-saving mode to the activation mode are that an uplink or optical network terminals (ONTs) connected to the OLT are into a state in which the uplink has packets to transmit to the ONT connected to the OLT or a state in which at least one of the ONTs connected to the OLT is in the power-saving mode and the remaining ONTs malfunction while the uplink has no packets to transmit to the ONT connected to the OLT.