JP5978168B2 - Subscriber side device and power saving control method for subscriber side device - Google Patents

Description

  The present invention relates to a technology for reducing power consumption in an optical communication system in which a station side device and a subscriber side device are connected via an optical fiber transmission line and transmit / receive by an optical signal.

  In an optical network, one station side device (OLT: Optical Line Terminal) is connected to one or a plurality of subscriber side devices (ONU: Optical Network Unit) and point-to-point or point-to-multipoint via an optical fiber transmission line. It is a network that communicates points.

  The configuration of a related optical communication system is shown in FIG. The optical communication system includes an OLT 2, an ONU 1, an optical fiber transmission line 3 and an optical splitter 4. The OLT 2 includes a signal processing unit 22, a transmission / reception unit 21, and a transmission / reception unit 23 having a SNI (Service Node Interface) physical layer unit. The ONU 1 includes a signal processing unit 12, a transmission / reception unit 13, a transmission / reception unit 11 having a UNI (User Network Interface) physical layer unit, and a power supply unit 14 that supplies power to each component.

  In the conventional telephone service using copper wire, the power fed from the station building is directly modulated in analog form with the voice input to the telephone, so even if a power failure occurs at the subscriber's home The telephone service could be used as long as power was supplied from the station building. On the other hand, in a telephone service based on an optical communication system, voice is encoded, an optical signal is transmitted to a station building device using a transmitter such as a laser, and transmission timing is controlled in a point-to-multipoint configuration. There is a need.

  As described above, when a telephone service is provided using an optical communication system, a subscriber-side device including a transmitter and a signal processing unit that performs encoding and transmission timing control is required on the subscriber side. Therefore, when a power outage occurs at the subscriber's home, the telephone service cannot be used unless power can be supplied to the equipment required for the telephone service using a battery or the like.

  However, even if the necessary equipment is operated by a battery during a power outage, if the speed of equipment parts is increased to meet the increasing traffic demand, the power consumption of the equipment will increase and the time that can be backed up by the battery will decrease. .

  Until now, for the purpose of reducing the power consumption of the network, an ONU sleep function for stopping the main functions of the ONU 1 while the traffic to be woken up has not been discussed. Among them, a technique called Fast Sleep or Doze, which is a sleep function that stops the transmitter / receiver 13 in a short time without disconnecting the link, is a G. Standardization is being promoted by 987.3 and the like, and it is expected as an effective technique for reducing the power consumption of ONU1.

ITU-T Recommendations G-series supplement 45: GPON Power Conservation, May 2009 “Practical Introductory Network Practical SIP Detailed Text 1st Edition”, Takuya Sawada, Toru Ikeda, Takehito Kinoshita, Tetsuo Nishizawa and Ryoo Kawashima, Rick Telecom Co., Ltd., April 2007. 179 IEFT RFC3261 SIP: Session Initiation protocol, May 2009

  However, FastSleep and Doze, which are premised on operating at high speed on the assumption that no layer 2 link breakage occurs, have few parts that can be stopped, and power consumption that can be reduced is limited.

  In addition, as with DeepSleep described in Non-Patent Document 1, even if the power supply that allows link disconnection of the layer 2 is stopped and the user wakes up only when making a call, it responds to the incoming call by the link disconnection. Otherwise, it will be a one-way telephone service that can only be called.

  Therefore, an object of the present invention is to realize low power consumption by stopping the power supply of a communication device while maintaining a higher layer session such as a telephone service.

  In order to achieve the above object, the present invention considers retransmission in the upper layer, and maintains the upper layer session by supplying power to the communication device before the retransmission processing is completed and making it ready for reception. In addition, the power consumption is reduced by stopping the power supply to the communication device within a range where the session does not end.

Specifically, the subscriber side device of the present invention is:
An optical network receiver that repeatedly receives a signal to wake up transmitted from a station-side device via a passive optical network over a predetermined first time;
A signal processing unit for processing a signal received by the optical network receiving unit;
A power supply unit that supplies power to the optical network reception unit and the signal processing unit;
Measures the duration of the sleep state in which power supply from the power supply unit to the optical network reception unit or the signal processing unit is stopped, and from the power supply unit in a second time shorter than the predetermined time A timer that starts power supply to the optical network reception unit or the signal processing unit and cancels the sleep state;
Is provided.

In the subscriber-side apparatus of the present invention, when the optical network receiving unit receives a predetermined signal, power is supplied from the power supply unit to the optical network receiving unit or the signal processing unit according to the received signal. There may be further provided a timer control unit for changing the wake-up time for maintaining the above .

In the subscriber side apparatus of the present invention, the time that the power supply unit stops supplying power is T _sleep , the time that the power supply unit supplies power is T _active , Assuming that the initial value of the signal retransmission interval is R1, and the number of times the signal to be woken up is n, the timer control unit satisfies that T _sleep satisfies Equation (1) and T _active satisfies Equation (2). A wake-up time for maintaining power supply from the power supply unit to the optical network reception unit or the signal processing unit may be set so that the power supply unit satisfies the condition and T _sleep / T _active is maximized.

In the subscriber side apparatus of the present invention, the time that the power supply unit stops supplying power is T _sleep , the time that the power supply unit supplies power is T _active , the retransmission interval of the signal and I, when the time-out period of a predetermined retransmission control and _{T timeout,} the timer control _{unit, T active} is _T satisfies the equation (3) the filled and _{T sleep} is equation (4) _active May be set so as to maintain the power supply from the power supply unit to the optical network reception unit or the signal processing unit .

Specifically, the power saving control method of the subscriber side device of the present invention is:
An optical network receiver that repeatedly receives a signal to wake up transmitted from a station-side device via a passive optical network over a predetermined first time;
A signal processing unit for processing a signal received by the optical network receiving unit;
A power supply unit that supplies power to the optical network reception unit and the signal processing unit;
A power saving control method for a subscriber side device comprising:
Measures the duration of the sleep state in which power supply from the power supply unit to the optical network reception unit or the signal processing unit is stopped, and from the power supply unit in a second time shorter than the predetermined time A sleep control procedure for starting power supply to the optical network reception unit or the signal processing unit and releasing the sleep state;

In the power-saving control method for a subscriber-side device according to the present invention, in the sleep control procedure, the time during which the power supply unit stops supplying power is T _sleep and the time during which the power supply unit supplies power. _Is T _active , the initial value of the retransmission interval of the signal to wake up is R1, and the number of times of transmission of the signal to wake up is n, the timer control unit sets T _sleep to the formula (1) the filled and as _{T active} satisfies the equation (2) and _T sleep _{/ T active} is maximized, the wake-up time for maintaining the power supply to said optical network reception section or the signal processing unit from the power supply unit It may be set .

In the power-saving control method for a subscriber-side device according to the present invention, in the sleep control procedure, the time during which the power supply unit stops supplying power is T _sleep and the time during which the power supply unit supplies power. was a _{T active,} the retransmission interval indicating signal to be the wake-up and I, when the time-out period of a predetermined retransmission control and _{T timeout,} the timer control _{unit, T active} is and satisfies the equation (3) A wake-up time for maintaining power supply from the power supply unit to the optical network reception unit or the signal processing unit may be set so that T _sleep satisfies Equation (4) and T _active is minimized .

  The above inventions can be combined as much as possible.

  ADVANTAGE OF THE INVENTION According to this invention, low power consumption is realizable by stopping the power supply of a communication apparatus, maintaining the session of an upper layer like telephone service.

It is a sequence diagram which shows an example of the session of the VoIP service by SIP. 1 is a configuration diagram illustrating an example of an optical communication system according to Embodiment 1. FIG. 4 shows an example of an INVITE message transmission interval according to the first embodiment. FIG. 6 is a sequence diagram illustrating an example of a VoIP service session according to the first embodiment. FIG. 5 is a configuration diagram illustrating an example of an optical communication system according to a second embodiment. An example of the transmission interval of the INVITE message which concerns on Embodiment 3 is shown. 14 illustrates an example of an INVITE message transmission interval according to the fourth embodiment. It is a block diagram which shows an example of the related optical communication system.

  Embodiments of the present invention will be described with reference to the accompanying drawings. The embodiments described below are examples of the present invention, and the present invention is not limited to the following embodiments. In the present specification and drawings, the same reference numerals denote the same components.

  When providing a service such as a telephone, a session is managed using a protocol such as SIP (Session Initiation Protocol). In SIP, a predetermined number of retransmissions are attempted before disconnecting a session, and the session is disconnected when communication is not successful for a certain period of time.

FIG. 1 shows the configuration of a related VoIP (Voice over IP) service by SIP. When a user makes a call to another user, a signal indicating that the terminal (UAC: User Agent Client) used by the user making the call should wake up to the other terminal (UAS: User Agent Server) via the SIP proxy server. A frame carrying an INVITE message is transmitted. If response is returned from the UAS In this case, SIP proxy server retransmits at the timer A ₀ of T1 seconds after sending the frame, response is returned even for retransmission after T1 seconds If not, retransmission is performed when the timer A _{1 that} has doubled T1 from the time of the timer A ₀ further elapses. The SIP proxy server repeats while doubling T1 for each retransmission, and transmits up to seven times (for example, see Reference 2). At this time, the value of the timer A which is the transmission interval of the INVITE message is timer A ₀ = T1 × 2 ⁰ , timer A ₁ = T1 × 2 ¹ , timer A ₂ = T1 × 2 ² ,... Timer A ₅ = T1 × ²⁵ .

(Embodiment 1)
An example of the configuration of the optical communication system according to the first embodiment is shown in FIG. The optical communication system according to the first embodiment includes a SIP server 8, an OLT 2, and an ONU 6. The OLT 2 and the ONU 6 are connected by an optical signal line including the optical splitter 4 and the optical fiber 3.

  As a subscriber-side device of the present embodiment, the ONU 6 is an optical network that performs transmission / reception to / from a passive optical network, a transmission / reception unit 11 having a UNI (User Network Interface) physical layer unit similar to FIG. A transmission / reception unit 13 that functions as a reception unit, a power supply unit 14 that supplies power to each component, and a timer 55 that periodically requests the power supply to start and stop power supply.

  The IP telephone 7 is connected to the ONU 6 via the transmission / reception unit 11. The OLT 2 that functions as a station side device is connected to the ONU 6 via the optical transmission path 3 and the optical splitter 4. The SIP server 8 is connected to the OLT 2 via an upper port of the OLT 2. The IP telephone 9 is connected to the SIP server 8 via a communication path. In this embodiment, the relay node is omitted for simplicity of explanation.

  When making a call from the IP telephone set 9 to the IP telephone set 7, an INVITE message is transmitted from the IP telephone set 9 functioning as a UAC to the SIP server 8. When receiving the INVITE message, the SIP server 8 transmits the INVITE message to the IP telephone 7 functioning as a UAS. However, the ONU 6 is in a sleep state in which the power supply from the power supply unit 14 is stopped, and the ONU 6 cannot receive the INVITE message while the link disconnection between the ONU 6 and the OLT 2 is occurring.

  The SIP server 8 resends the INVITE message if no response is returned from the IP telephone 7 within the time determined as the timer A. The SIP server 8 doubles the value of the timer A and performs further retransmission if no response is returned. This INVITE message is transmitted up to a maximum of seven times while the retransmission interval defined as timer A is doubled.

  An example of the transmission interval of the INVITE message when the initial value 500 ms of the timer A described in Non-Patent Document 2 is employed is shown in FIG. As shown in FIG. 3, the transmission interval of the INVITE message is 500 ms, 1 s, 2 s, 4 s, 8 s, 16 s, and the elapsed time from the transmission of the first INVITE message is 500 ms, 1.5 s, 3.5 s, 7 .5s, 15.5s, and 31.5s.

  FIG. 4 shows an example of a session according to the present embodiment. If the SIP server 8 exceeds the timer B, which is a predetermined first time, and does not respond to the INVITE message, the SIP server 8 ends the retransmission process. The timer B is defined based on the initial value of the timer A and is, for example, a value obtained by multiplying the initial value of the timer A by 64. For this reason, for example, when the timer 55 exceeds 32 s and the stop of power supply is requested, there is a possibility that the IP telephone 7 cannot receive a call. Therefore, in order to make the IP telephone 7 receive a call, it is necessary to receive any message from the start of the transmission of the INVITE message to the seventh transmission transmitted when 31.5 s has elapsed.

  Therefore, as shown in FIG. 4, the power saving control method for the subscriber side apparatus according to the present invention is set so that power is supplied to the timer 55 in advance in a second time shorter than the timer B at which the retransmission process ends. A sleep control procedure. In the present embodiment, for example, the duration of the sleep state is set in the timer 55 so that the ONU 6 can be received in a 31 s cycle shorter than 31.5 s. For example, the power supply unit 14 switches between the sleep state and the active state each time the timer 55 measures the duration of 31 s.

  If the INVITE message is transmitted when the ONU 6 becomes receivable by retransmitting the INVITE message by the OLT 2 or using the buffer, the INVITE message can be transferred to the IP telephone 7 and a response can be returned before the timer B expires. . Therefore, the ONU 6 according to the present embodiment can reliably provide incoming calls.

  As described above, in the present invention, it is possible to stop the power supply to a large part of the communication equipment because it takes a long time to stop the power supply by considering the layer 2 link disconnection. Electric power can be reduced. In addition, since the upper layer session providing the telephone service is held, a procedure necessary for re-establishing the session is omitted, so that a response can be made in a short time after the power supply is resumed. Furthermore, by considering the retransmission processing, the power supply stop time can be further extended, the power supply time can be shortened, and the incoming call can be reliably answered.

(Embodiment 2)
An example of the configuration of the optical communication system according to the present embodiment is shown in FIG. In the ONU 6 according to the present embodiment, the ONU 6 further includes a timer control unit 56. The timer control unit 56 controls the timer 55 so as to maintain a wake-up for a certain period of time when receiving the INVITE message. The power supply unit 14 keeps getting up until an instruction is received from the timer 55. As a result, the ONU 6 can maintain a receivable state during the time from when the INVITE message is received until the voice communication is started, so that it is possible to reliably provide the start of the voice communication.

  Further, it is preferable that the ONU 6 maintain a wake-up for a certain period of time upon reception of an RTP (Real-time Transport Protocol) packet for voice communication. Therefore, the timer control unit 56 controls the timer 55 so as to maintain the wake-up from the start of the voice communication until the end of the voice communication. The power supply unit 14 keeps getting up until an instruction is received from the timer 55. Thereby, voice communication can be reliably provided without being disconnected in the middle.

  Furthermore, it is preferable that the ONU 6 reads the header information of the message and continues to wake up for a certain time only when a specific message is received. Specifically, a value indicating high priority is described in the ToS (Type of Service) field in the IP header of the INVITE message or RTP packet that is the traffic to be woken up, and the timer control unit 56 is described in the ToS field. Continue to wake up for a certain period only when high priority traffic is received. The place where the priority is described is not limited to the ToS field, and a value indicating high priority may be described in a CoS (Class of Service) field in the VLAN tag of the INVITE message or the RTP packet. In this way, only when a value indicating high priority is described in a field indicating a specific message, the user can wake up carelessly by receiving an unnecessary packet, and maintain power consumption. Can be prevented from increasing.

(Embodiment 3)
The configuration described in this embodiment is the same as that shown in FIG. The difference between the first embodiment and the second embodiment is a setting method of the timer 55. In the first embodiment, the timer 55 is set so that it can be received in a 31 s cycle before the expiration of the timer B. However, if no retransmission processing or buffering is performed in the OLT 2 or the relay node, the ONU 6 sends an INVITE message. There is a possibility that the IP telephone 7 cannot receive a call without receiving it.

Arrival of the INVITE message from the SIP server 8 when the traffic to be woken up is retransmitted 500 ms after the first transmission, and is retransmitted with a retransmission time varying from 1 s, 2 s, 4 s, 8 s, and 16 s until the seventh transmission. An example of the timing is shown by a black circle in FIG. In this case, the time when the ONU 6 cannot receive the signal from the OLT 2 is T _sleep , the time when the ONU 6 can receive the signal from the OLT 2 is T _active , the initial value of the retransmission interval of the INVITE message is R1, and the INVITE message Assuming that the number of transmissions is n, the ONU 6 of the present embodiment satisfies all the conditions of the expressions (1) and (2), and sets T _active and T _sleep to increase the T _sleep / T _active as much as possible. Set.

Specifically, as in the first embodiment, the initial value 500 ms of the timer A is adopted, and the number of retransmissions is increased to 6 and the retransmission interval is doubled except for the first transmission. N = 4 as a small value. In this _case, it can be received in _T sleep _{+ T active <15.5sT} active satisfies the _{T active>} 8s. For this reason,
T _sleep <15.5s
T _active > 8s
A value that satisfies all of the above conditions and makes T _sleep / T _active as large as possible is set.

For example, if the set granularity of the timer 55 is 100 ms, T _active is set to 8.1 s, and T _sleep is set to 15.4 s. As shown in FIG. 6, since retransmission is always included in the T _active period at any timing, it is possible to reliably provide an incoming call.

Further, by setting T _sleep / T _active as large as possible, the time for stopping the power supply with respect to the time during which the power is supplied is lengthened, so that the power consumption can be further reduced.

(Embodiment 4)
The configuration described in the fourth embodiment is the same as that shown in FIG. The difference from the first embodiment is a method for setting the timer 55. In the first embodiment, the timer 55 is set so that it can be received in a 31 s cycle before the expiration of the timer B. However, in this embodiment, when the OLT 2 receives the INVITE message, as shown in FIG. , It is assumed that the OLT 2 repeatedly performs the INVITE message retransmission process at a fixed interval I determined separately.

The time during which the power supply unit 14 stops power supply is T _sleep , the time during which the power supply unit 14 supplies power is T _active , the retransmission interval by the OLT 2 is I, and a predetermined retransmission control is performed. Let the timeout time be T _timeout . In this case, the timer control unit _{56, T active} is meets and _{T sleep} Equation (3) sets the second time _{T sleep of T active} satisfy the equation (4) becomes minimum.
(Equation 3)
T _active > I Formula (3)
(Equation 4)
T _sleep = T _timeout −T _active formula (4)

When the setting granularity of the timer 55 is 100 ms and the INVITE message to be woken up by the OLT 2 is repeatedly transmitted at a cycle of 0.1 s, the timer control unit 56 sets T _active from I = 0.1 s based on the equation (3). Also set to 0.2 s long. Further, the timer control unit 56 sets 31.8 s obtained by subtracting T _active from 32 s set for the timer B based on the equation (4).

In this embodiment, since T _active is 0.2 s, ONU 6 is in a receivable state for a time longer than I = 0.1 s, which is the retransmission interval of the INVITE message by OLT 2. As a result, the ONU 6 of the present embodiment can reliably provide an incoming call regardless of the retransmission timing of the INVITE message. Further, since T _active can be reduced as much as possible and T _sleep can be increased, power consumption can be further reduced in order to increase the time during which power supply is stopped relative to the time during which power is supplied. it can.

  The present invention can be applied to the information communication industry.

1, 6: ONU
2: OLT
7, 9: IP telephone 8: SIP server 11, 13, 21, 23: Transmission / reception unit 12, 22: Signal processing unit 14: Power supply unit 55: Timer 56: Timer control unit

Claims (4)

An optical network receiver that repeatedly receives a signal to wake up transmitted from a station-side device via a passive optical network over a predetermined first time;
A signal processing unit for processing a signal received by the optical network receiving unit;
A power supply unit that supplies power to the optical network reception unit and the signal processing unit;
Measures the duration of the sleep state in which power supply from the power supply unit to the optical network reception unit or the signal processing unit is stopped, and from the power supply unit in a second time shorter than the predetermined time A timer that starts power supply to the optical network reception unit or the signal processing unit and cancels the sleep state;
The time during which the power supply unit stops power supply is T _sleep , the time during which the power supply unit supplies power is T _active, and the initial value of the retransmission interval of the signal to wake up is R1 And the number of transmissions of the signal to wake up is n, so that T _sleep satisfies equation (C1), T _active satisfies equation (C2), and T _sleep / T _active is maximized. A timer control unit for setting a wake-up time for maintaining power supply from the power supply unit to the optical network reception unit or the signal processing unit;
A subscriber-side device.

An optical network receiver that repeatedly receives a signal to wake up transmitted from a station-side device via a passive optical network over a predetermined first time;
A signal processing unit for processing a signal received by the optical network receiving unit;
A power supply unit that supplies power to the optical network reception unit and the signal processing unit;
Measures the duration of the sleep state in which power supply from the power supply unit to the optical network reception unit or the signal processing unit is stopped, and from the power supply unit in a second time shorter than the predetermined time A timer that starts power supply to the optical network reception unit or the signal processing unit and cancels the sleep state;
The time during which the power supply unit stops supplying power is T _sleep , the time during which the power supply unit supplies power is T _active , the retransmission interval of the signal to wake up is I, and When the timeout period for a defined retransmission control and _{T timeout,} so _{T active} satisfies the formula (C3) and _{T sleep} satisfies the formula (C4) _{T active} is minimized, the optical network from the power supply unit A timer control unit for setting a wake-up time for maintaining power supply to the reception unit or the signal processing unit;
A subscriber-side device.
(Number C3)
T _active > I Formula (C3)
(Number C4)
T _sleep = T _timeout −T _active expression (C4) An optical network receiver that repeatedly receives a signal to wake up transmitted from a station-side device via a passive optical network over a predetermined first time;
A signal processing unit for processing a signal received by the optical network receiving unit;
A power supply unit that supplies power to the optical network reception unit and the signal processing unit;
A timer control unit for changing a wake-up time for maintaining power supply from the power supply unit to the optical network reception unit or the signal processing unit;
A power saving control method for a subscriber side device comprising:
Measures the duration of the sleep state in which power supply from the power supply unit to the optical network reception unit or the signal processing unit is stopped, and from the power supply unit in a second time shorter than the predetermined time and starts power supply to the optical network reception section or the signal processing unit have a sleep control procedure for canceling the sleep state,
In the sleep control procedure,
The time during which the power supply unit stops power supply is T _sleep , the time during which the power supply unit supplies power is T _active, and the initial value of the retransmission interval of the signal to wake up is R1 When the number of transmissions of the signal indicating that the user should wake up is n, the timer control unit satisfies that T _sleep satisfies Equation (C5), T _active satisfies Equation (C6), and T _sleep / T _active is the maximum. Setting a wake-up time for maintaining power supply from the power supply unit to the optical network reception unit or the signal processing unit,
A power saving control method for a subscriber side device.

An optical network receiver that repeatedly receives a signal to wake up transmitted from a station-side device via a passive optical network over a predetermined first time;
A signal processing unit for processing a signal received by the optical network receiving unit;
A power supply unit that supplies power to the optical network reception unit and the signal processing unit;
A timer control unit for changing a wake-up time for maintaining power supply from the power supply unit to the optical network reception unit or the signal processing unit;
A power saving control method for a subscriber side device comprising :
Measures the duration of the sleep state in which power supply from the power supply unit to the optical network reception unit or the signal processing unit is stopped, and from the power supply unit in a second time shorter than the predetermined time and starts power supply to the optical network reception section or the signal processing unit have a sleep control procedure for canceling the sleep state,
In the sleep control procedure,
The time during which the power supply unit stops supplying power is T _sleep , the time during which the power supply unit supplies power is T _active , the retransmission interval of the signal to wake up is I, and Assuming that the determined timeout time for retransmission control is T _timeout , the timer control unit sets the power so that T _active satisfies Expression (C7) and T _sleep satisfies Expression (C8) and T _active is minimized. Setting a wake-up time for maintaining power supply from the supply unit to the optical network reception unit or the signal processing unit,
A power saving control method for a subscriber side device .
(Number C7)
T _active > I Formula (C7)
(Number C8)
T _sleep = T _timeout −T _active equation (C8)

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