HK1158402B - System and method for providing power management strategy for multi-media coaxial alliance - Google Patents

Description

System and method for providing multimedia over coax alliance power management policies

Technical Field

The present invention relates to information networks, and more particularly to the transmission of information, such as multimedia information, over communication lines, such as coaxial cables, to form communication networks.

Background

Home networking technology using coaxial cables is known. Multimedia over coax alliance (MoCA)^TM) On its website mocallance, org, there is provided a suitable specification for the networking of digital video and entertainment over existing coaxial cables in homes distributed among open members (moca 1.1). The moca1.1 specification is incorporated herein by reference in its entirety.

The home network accesses the unused bandwidth available to a large number of home coax cables via coax cables. Over 70% of the homes in the united states have coaxial cables installed in the home infrastructure. Many homes have coaxial cables at one or more major entertainment sites using a network, such as a home active room, a multimedia zone, and a master bedroom. Home networking technology allows homeowners to use this infrastructure as a network system and deliver other entertainment and information programs using the high quality of service (QoS).

Home networking technology using coaxial cable provides high speed (270mbps), high quality services, and state of the art to protect the innate security and packet-level encryption of wired connections. Coaxial cables are designed to carry high bandwidth video. Today, it is commonly used to securely transmit millions of dollars of pay-per-view and day-to-day video content. A home network employing coaxial cable may also be used as a backbone for multiple wireless access points that are used to extend the wireless network throughout the user's home.

Home networks using coaxial cable provide consistent, high throughput, high quality connections to locations where video equipment is located within the home through existing coaxial cable. Home networks using coaxial cable provide the primary link for digital entertainment and may also be compatible with other wired or wireless networks, thereby extending the entertainment experience in the home.

Currently, home networks using coaxial cable operate using access technologies such as ADSL and VDSL or Fiber To The Home (FTTH). These technologies are typically accessed into the home over twisted pair or fiber, operating in the hundreds of kilohertz to 8.5MHz band for ADSL and 12MHz band for VDSL. When services reach the home via xDSL or FTTH, they can be routed to video equipment via the home network using coax technology and home coax. Cable functions, such as video, voice, and internet access, may be provided to the home by a cable operator over coaxial cable and used within the home running coaxial cable to reach a single cable service using equipment located in different rooms of the home. Typically, home networks employing coaxial cable type functionality run in parallel with cable functionality on different frequencies.

It is desirable to employ MoCA devices connected to a MoCA home network to achieve maximum power savings.

Disclosure of Invention

A system and/or method for achieving maximum power savings using MoCA devices connected to a MoCA home network, the system and/or method being substantially as shown in and/or described in connection with at least one of the figures, as set forth more completely in the claims.

According to one aspect, there is provided a network employing coaxial cables, the network comprising:

a network controller;

a plurality of network nodes, each network node comprising an integrated circuit, each integrated circuit comprising a plurality of circuit modules;

wherein each of the network nodes is configured to be in:

an operating power state; and

a standby power state including an active mode and an idle mode; and is

In the active mode, the network node is configured to transmit and/or receive information data packets; and

in the idle mode, a network node is configured to remain connected to the network while being one

Part of the circuit modules are powered down, thereby reducing power consumption of the network node.

Preferably, each of the network nodes is configured to switch from an idle mode to an active mode after a predetermined number of Medium Access Plans (MAPs).

Preferably, each said network node is configured to switch from an idle mode to an active mode following a network beacon signal.

Preferably, each said network node is configured to receive an interrupt signal over a link to said network.

Preferably, a portion of the circuit module includes a clock portion that provides a clock signal to the digital PHY layer.

Preferably, a portion of the circuit module includes a clock portion that provides a clock signal to the multimedia access controller layer.

According to an aspect of the present invention, there is provided a method of communicating between a plurality of network modules through a coaxial cable backbone in a home network, the home network including the plurality of network modules, one of the plurality of network modules being a network controller, each of the plurality of network modules being connected to the coaxial cable backbone; the method comprises the following steps:

receiving, using a master module, a request for broadband transmit pulses from the plurality of network modules, the request being transmitted over a coax backbone;

establishing a sequence of transmit opportunities for the plurality of network modules to track when pulses are transmitted directly to other network modules through the coax backbone; and

triggering, using a master module, each network module between a run power state and a standby power state, the standby power state including an active mode and an idle mode; wherein:

in the active mode, the network node is configured to transmit and/or receive information data packets; and

in the idle mode, a network node is configured to remain connected to the network while being one

Part of the circuit modules are powered down, thereby reducing power consumption of the network node.

Preferably, the method further comprises switching the network module from the idle mode to the active mode after a predetermined number of Medium Access Plans (MAPs).

Preferably, the method further comprises switching the network module from the idle mode to the active mode after the network beacon signal.

Preferably, the method further comprises configuring a network module to receive an interrupt signal over a link to the network.

Preferably, the method further comprises gating a clock signal provided to the digital PHY layer.

Preferably, the method further comprises gating a clock signal provided to the MAC layer.

Drawings

The invention will be further described with reference to the accompanying drawings and examples, in which:

FIG. 1 is a schematic diagram of a MoCA core module;

FIG. 2 is a schematic diagram of a conventional operation sequence of a MoCA node (EN) entering a standby state;

FIG. 3 is a schematic diagram of an operational sequence for EN re-entering the run state;

FIG. 4 is a schematic diagram of another embodiment of a run sequence sent to an EN in a standby state;

FIG. 5 illustrates an exemplary embodiment of a system that can reduce power consumption in a MoCA network using the methods described herein;

FIG. 6 is a schematic diagram of the operation of the standby state according to the present invention;

FIG. 7 is a schematic diagram of an operational sequence of a standby node according to the present invention;

FIG. 8 is a schematic illustration of power associations of network devices in a system according to the present invention;

FIG. 9 is a schematic diagram of a power state transition sequence according to the present invention;

FIG. 10 is a schematic diagram of active standby/idle standby mode transitions of a MoCA node participating in periodic Link Maintenance Operations (LMOs), in accordance with the present invention;

FIG. 11 is a schematic diagram of a single chip module or a multi-chip module in a data processing system of the present invention.

Detailed Description

In the following description of the embodiments, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration different embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural and functional modifications may be made without departing from the scope and spirit of the present invention.

As will be appreciated by one of skill in the art in light of the following disclosure, aspects described herein may be embodied as a method, data processing system, or computer program product. Accordingly, these aspects may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, these aspects may take the form of a computer program product stored by one or more computer-readable storage media having computer-readable storage code embodied in the medium; or in the form of instructions embedded on or within a storage medium. Any suitable computer readable storage medium may be utilized including hard disks, CD-ROMs, optical storage devices, magnetic storage devices, and/or any combination thereof.

Further, various signals representing data or events as described herein may be transmitted between a source and a destination in the form of electromagnetic waves through signal-conducting media, such as metal wires, optical fibers, and/or wireless transmission media (e.g., air and/or space).

The specification describes a method of implementing a power save mode for MoCA devices that can operate in compliance with the current MoCA1.1 specification and a suitable MoCA protocol that conserves power output. The present invention provides a protocol in which MoCA devices can be in a standby state. The standby state may reduce the power consumption of the device while allowing the device to be fully instantaneously reactivated either locally (i.e., on the front panel of the set-top box or remote IR) or remotely (i.e., from a different network device in the home). Remote reactivation may occur through MoCA.

For ease of reference, the following glossary provides definitions of the various abbreviations and symbols used in the present patent application:

ARP address resolution protocol

The digital PHY includes ports of the MoCA integrated circuit that form channels that transmit signals to the receiver integrated circuit or receive signals transmitted by the transceiver integrated circuit.

EN MoCA existing node (the term "node" may also be referred to herein as a "module")

IE information element

IPV4 IP version 4

IPV6 IP version 6

A MAC media access controller comprising logic of a MoCA integrated circuit to time the digital PHY on and off as needed to send signals to or receive signals from the receiver integrated circuit.

MAP medium access plan

NC MoCA network controller

NN MoCA new node

PD shutdown

Physical layer of PHY MoCA network

PS power saving

PU power-on

PO reservation request opportunity

RR reservation request message

STB (set Top Box)

SV Standby vector

WoM awakening on MoCA

Several organizations, including the EC (european union) and the energy star organization in the united states, provide recommendations to reduce total energy consumption in homes. Among other devices, STBs, digital televisions and other video/network devices are considered in the recommendations.

Network devices, such as network STBs, should preferably maintain their network in an "active (1 ive)" state, even in a power-save mode, to wake up remote nodes. This is commonly referred to as wake-on-LAN. Both energy star and EC provide recommendations that network devices be in standby state but need to keep their network connections open.

Wake-up on lan (wol) is currently specified for ethernet and is considered for WiFi. Since MoCA becomes the primary home network platform to connect users' electronic devices, it must have a wake-up feature on MoCA. Although the current MoCA1.1 specification does not make any definition of power saving, it is possible to achieve significant power saving according to the invention while keeping the MoCA network connection open in standby state.

The following aspects relate to MoCA-related power saving mode requirements, current power consumption of the MoCA core, and systems and techniques for power saving operating modes associated with EC CoC and energy Star recommended standby states. The power saving technique according to the invention conforms to moca 1.1. The technique according to the invention is applicable to networks in which nodes can be configured in a standby state according to the invention. According to the invention, such a network also comprises a network comprising only nodes according to the invention. The active power save mode according to the present invention may run on the current MoCA specification and wake up on the MoCA protocol transaction according to the present invention as described below.

According to the invention, the preferred requirements of the MoCA Standby state are summarized as follows:

1. a significant reduction in power compared to run time, i.e., active rather than standby;

2. in the power saving mode, keeping the network connected with the remote MoCA;

3. the nodes in the standby state should keep the MoCA in an active state, and will be defined in the part of the specification related to the awakening of the MoCA equipment;

4. supporting the coexistence of running and standby nodes on the MoCA network;

5. configuring the nodes to be in a standby state and simultaneously coexisting with equipment of other MoCA manufacturers; and

6. active and idle times are allocated to increase power consumption savings (discussed in more detail in the portion of the specification corresponding to fig. 6).

The following section outlines the power saving states of the MoCA cores and their corresponding power consumption specifications.

Power management specification

This section summarizes the power requirements. See Olivier Harel for MoCA&Power management, fromhttp://twiki-01.broadcom.com/bin/view/Chiparch/MoCAPowerManagementThe requirements of EC CoC and energy star are described in more detail herein, incorporated by reference in their entirety.

Standby state and power target

EC suggests two standby states of the user's electronic device and their corresponding power targets: 1) passive standby state-currently 2 watts (W) of Alternating Current (AC) is allowed per set-top box, but the power is planned to be reduced to 1WAC (aggressive) standby mode in the near future. EC CoC does not require network connectivity in passive standby mode, but some european countries require network connectivity to be maintained. 2) Active standby state-requires the maintenance of a network connection between network devices. The power requirement is 3WAC per set top box.

The energy star defines a single standby state. The energy star recommendation is for the total power consumption of the set-top box per year, assuming that it is in standby for more than 50% of the time. There is no specific suggestion for power consumption at standby. However, greater power consumption is allowed in the run mode. Harel assumes that each set-top box of the energy star consumes 3WAC when in standby.

Some of the power consumptions associated with the selected power consumption states are as follows:

aggressive passive standby of 1W AC in Europe allows 300mW BRCM 7420 manufactured by Broadcom corporation of Irvine, Calif. The only consumption allowed by MoCA core consumption is standard battery exposure. By limiting the use of low voltage critical (LVT) cells, standard cell leakage is kept low. Preferably, all analog components should be powered down (< 1mW) and it is acceptable that there is no activity of any kind.

The european passive standby state allows 2W AC, convertible to about 1W DC for set-top boxes.

Energy star (us) ES assumes that the set-top box can reach 3WAC in standby; this can be converted (using an OK or other suitable converter) to just over 1.5W DC for the entire set-top box.

MoCA standby power requirement of Harel

The allowed total standby power of BRCM 7420 and the implied allowed power consumption (auxiliary chip LNA/PARF (low noise amplifier/power amplifier) (rf transmission chip) when working with BRCM 3450 manufactured by Broadcom Corporation of Irvine, california) are listed in table 1.

The analysis in table 1 assumes that, in addition to MoCA, both the update DDR (double data rate) and ethernet systems connected to the MoCA core are ON, and the latter consumes 500 to 600mW of power. In the standby state listed in table 1, the MoCA is connected to the ethernet subsystem, but is mostly in idle mode. Some embodiments of the invention may include waking the ethernet subsystem in response only when the MoCA core according to the invention applies filtering, generating an interrupt signal, thereby reducing power consumption of the ethernet subsystem, as described in more detail below.

Table 1: RF module power consumption

Table 2 shows a MoCA network state standby configuration according to the present invention.

In standby, active mode, the MoCA network should remain on, although no data is transmitted, but remain connected. In idle standby mode, it is not mandatory, but desirable, to keep the network on. And in the attack idle mode, the network is closed, and the MoCA core is powered down.

Typically, the MoCA node switches between an operational state and a standby state in response to a signal external to the node. The MoCA node switches between different standby modes in response to a trigger signal internal to the node.

Table 2: MoCA network state at power state

In some embodiments, the wake-up time (to resume data transmission/reception operations from the idle mode in the MoCA standby state) is preferably kept below 20 milliseconds, and more preferably below 10 milliseconds.

The time required from power down to wake-up is typically longer than the time required from standby to wake-up. The time from power down to wake up requires the node to be re-admitted by the network. Re-admission should not exceed 2 seconds, assuming no channel search is required.

Since only leakage power is allowed during aggressive passive standby, the MoCA core is required to be restarted. The restart typically increases in power-up time by 75 milliseconds.

MoCA core power consumption

This part relates to the power consumption of the main power consumption module of the MoCA core. The total power consumption reduction in several operating modes according to the invention is analyzed.

This section explains the amount of power savings achieved by improving power consumption and PU/PD (power on/power off) time of the different modules.

Detailed Description

FIG. 1 shows a schematic diagram of a circuit block that consumes power in a MoCA integrated circuit ("chip"). The circuit shown in fig. 1 may or may not be integrated into another integrated circuit. Block 102 illustrates a typical blond 3450 chip, manufactured by blond corporation of california gulf, and which may be used with the MoCA integrated circuits described herein. In some embodiments, the boson 3450 chip is powered down by receiving a clock signal and/or receiving a power control line signal. Block 114 shows sending a local oscillator signal from a direct digital frequency synthesizer 120. The direct digital frequency synthesizer 120 receives a MoCA _ REF PLL 118(MoCA reference phase locked loop signal) from the external clock signal generator 116.

The external clock signal generator 116 may also provide a clock signal to the MoCA core 122, which preferably runs continuously when the MoCA core 122 generates a MoCA network clock.

MoCA core 122 provides PHY sysclk (system clock) to digital PHY 110 (physical layer of MoCA device), network clock to system/MAC 112, and SYS clk to CPU114 (processor for MoCA). CPU114 may be implemented as a MIPS or other suitable processor.

MoCA core 122 may also provide signals to USDS _ PLL (PHY _ PLL)124(PHY phase locked loop), which USDS _ PLL (PHY _ PLL)124 may in turn provide clock signals to analog-to-digital converter circuit 126 and digital-to-analog converter circuit 128. Although the old MoCA specification does not allow switching between the analog-to-digital converter circuit 126 and the digital-to-analog converter circuit 128 for down-time reasons. However, because of the short power-up and power-down times of its ADC/DACs, MoCA 2.0 preferably allows switching between the analog-to-digital converter circuit 126 and the digital-to-analog converter circuit 128 when necessary to save power.

In some embodiments according to the invention, to conserve power but maintain the MoCA's connection to the network, the network clock generated by chip 122 and the network timer located in system/MAC 112 may remain in an on state. However, the gated clock to digital PHY 110 and the gated clock to system/MAC 112 may be selectively turned off, thereby powering down digital PHY 110 and system/MAC 112. Thus, a large portion of power may be saved by selectively providing the network clock to digital PHY 110 and system/MAC 112.

A network timer (typically programmed by software) provides a signal to the CPU 114. The timer receives a network clock signal from chip 122. When the timer expires, the timer may reactivate (reactivate) the CPU114 by waking the CPU114 with an interrupt signal.

Preferably, since MoCA is a collaborative network, the timing of future events is deterministic-that is, the timing of at least one MAP cycle in the future and at least one beacon (10MPA cycle) in the future should be known. Thus, different modules may be activated in advance so that they can be prepared to transmit at a known point in time.

For example, if the MoCA core knows that it will receive a transmission at time t, it can reactivate the necessary modules at time t- Δ, where Δ is the time required to resynchronize the network clock.

Table 3 shows the RF power consumption for selecting the module shown in fig. 1 in different modes according to the present invention.

Table 3: RF module power consumption

The switching times of the LO and PLL in table 3 are assumed that the PLL has been synchronized; otherwise the PLL acquisition needs to be increased by another 1 ms.

In the active state, the power consumption of transmission/reception ("TX/RX") depends on the actual data transmission. The RF section may preferably be maintained in a power down mode when no data is being transmitted or received. However, due to the long LO switching time, the PLL/LO needs to remain on during normal operation.

In the standby state, transmit/receive switching is appropriate for those cases where the time interval is long enough to power down the LO/PLL.

Table 4 shows the power estimates for the analog-to-digital converter/digital-to-analog converter (ADC/DAC) in different modes.

Table 4: converter module power consumption

In some embodiments, this may prevent the ADC and/or DAC from being set to a power down mode due to the long power up time of the ADC and DAC, respectively. In other embodiments, when the ADC/DAC has a short power transition (switching) time, the ADC/DAC can be switched to save power.

Table 5 shows ADC digital power estimation in different modes

Table 5: MoCA digital module power consumption

In the run state, the MoCA logic circuit is activated. At the clock-only node-logic circuit is not activated but the clock is not gated. At the gated clock node-power consumption is primarily due to leakage. To estimate CPU power consumption in gated clock mode, assume that the CPU enters the WAIT state when the node is idle. Gating clocks may preferably be performed for the PHY and system/MAC modules. It is assumed that in a standby state according to the present invention, even in an active mode, the PHY and MAC will not be activated and therefore their clocks will be gated. The CPU may exit the WAIT state in response to a timer interrupt.

Power consumption estimation of MoCA core during normal operation

FIG. 6 shows the power consumption estimation for an existing MoCA node (EN) in two cases:

1) when there is no data transmission, the expected power consumption at the idle node (neither transmitting nor receiving) when the MoCA node is in standby is about 1.4W and can be reduced to about 1.0W if a strobe signal is used according to the present invention.

2) Maximum traffic load: MoCA is expected to consume 2.7W on average.

Table 6: MoCA node power consumption

The power consumption estimation is based on the following assumptions: transmitting a single MAP and a single control message per MAP period; five RR messages are sent per MAP cycle (worst case); MAP cycle length is 1 microsecond; the length of the MAP, RR and control non-data frames (MoCA network control frames) LMO, SEC, PROBE, KEY (Security) are all about 52 microseconds; when activated, nodes are receiving and transmitting 50% of the time; when idle, the RF is powered down and the clock is gated where it is available; and in full MoCA traffic load, the node is active 90% of the time.

The MoCA protocol allows significant power consumption when the network is on but no data is being transmitted over the network. In the method according to the invention, the Network Controller (NC) may increase the MAP cycle duration to 2.5ms, while allowing a single reservation request opportunity (reservation request opportunity) per MAP cycle. In one embodiment, all nodes are preferably required to receive or transmit less than 10% of the time, while the RF/ADC and PHY modules will be idle for the other 90% of the time.

Power saving mechanism according to the invention (MoAC 1.1 compatible)

In this section, the power consumption of MoCA En is estimated when it is in standby state. According to the present invention, a three-stage power saving mode is determined. The implementation of these modes depends on the cooperative work requirements:

MoCA1.1 network with NC not being a node according to the invention

In this mode, the MoAC core operates as a node that is in an operational state and has no data to send or receive. For about 85% of the time, the core is in its PHY/RF idle mode. When idle, the clock is gated and the RF is powered down. Because of the long power-up time, the PLL and ADC cannot be powered down.

In this mode, the MAP period is assumed to be about 1 millisecond on average.

MoCA network where NC is a node according to the invention-in one embodiment, it can be set to a standby state according to the invention-however, EN can be a node according to the invention or a legacy node

In this mode, the NC may adapt the MAP cycles to the network activity by increasing the MAP cycle duration and reducing the periodicity of the ROs to a single RO per MPA cycle for a node according to the invention in standby state (even lower when only the node according to the invention is located on the network).

In this mode, when no data is being sent on the network, the EN can leave the idle state every 2.5 milliseconds, and the PLL and RF can power down and gate the clocks. Except when the power-up time of the ADC is significantly improved, it cannot be powered down.

This mode is preferably fully compatible with MoAC 1.1 and can work in conjunction with legacy nodes. However, when the network accommodates legacy nodes, the NC according to the invention may require more power to support them.

MoCA1.1 in which NC and all nodes are nodes according to the invention

In one embodiment of the invention, the mode is such that the node according to the invention is woken up only once in a predetermined time-e.g. 10 microseconds-to further reduce power consumption. In this mode, the PLL and ADC are preferably powered down. The messaging method according to the invention is preferably compatible with available MoCA1.1 (see the description below for details).

In this way, further power savings can be achieved by effectively switching the RF/ADC/PHY/MAC module between run and standby states and significantly reducing power consumption when in the standby state.

Table 7 shows the expected power consumption on each power saving mode, and here, "proprietary" refers to a node that can be configured according to the standby state and the mode shown in table 2:

table 7: EN power saving mode

To simplify the discussion of the integration of the node MoCA, 4 corresponding start-up improvement configurations are defined in table 8, supra&Power interface ("ACPI") Specification [4][www.acpi.info]The MoCA core power saving states M0 through M3, incorporated herein by reference.

Table 8

Table 9 below illustrates possible switches from power saving mode and their associated commands:

table 9

This section details an embodiment for a power saving technique according to the present invention where the entire MoCA network includes nodes according to the present invention. This mode is preferably MoCA compatible, however, it may rely on proprietary messages running over the MoCA1.1 protocol.

Fig. 2 shows a schematic diagram of an alternative sequence of ENs entering a standby state.

Step 210 shows sending a request to the NC to enter a standby state by asserting the node that enters the Standby Vector (SV) information element of its full reservation request frame in conjunction with its node _ ID (i.e., no request to send opportunity).

Step 202 shows the NC acknowledging the standby transition of EN by asserting a bit with the node _ ID of the requester into the Standby Vector (SV) information element of the MAP frame. This is illustrated by the ACK message along the curved hatching adjacent to the running NC line.

The NC preferably reduces the periodicity of scheduled ROs for pending nodes to one RO per beacon period.

Step 203 shows that in the last MAP frame before the beacon, the NC asserts that all bits in the next MAP vector (NV) information element are combined with the standby node. The assertion indicates to the running node that a request to send to the standby node can be made at the next scheduled request opportunity. These transmissions may be made because the standby node will preferably receive and parse MAP frames in the next MAP period. The EN switches to the active mode at the next predetermined beacon to acquire the predetermined time for the next MAP frame and reenters the idle mode. Thus, step 204 shows the standby node receiving the beacon. The beacon is simply where the first MAP is. The standby node may receive a first MAP frame targeted (step 205) and parse the MAP frame.

Repeated execution of steps 203 and 204 shows that if an EN loses a MAP frame, it can be reacquired at the next beacon cycle.

Step 206 shows that if there are no pending frames to send, the EN may send an RR after the first MAP after the beacon (at MoCA 2.0).

In step 205, MAP parsing generates two possible scenarios (scenarios): if the bit associated with the next MAP vector (NV) has been asserted, the standby node will receive the next MAP (step 207). The scenario may repeat itself until the bit in conjunction with the next MAP vector (NV) is deasserted (step 208). Once deasserted in conjunction with the bit of the next MAP vector (NV), the standby node re-enters the idle mode for the next scheduled beacon (step 204) and ignores any remaining concurrent MAPs in the current beacon period (step 209). The curved hatching along the left side of the line for node S represents those standby nodes that receive an active standby mode.

Fig. 3 shows a schematic diagram of an alternative sequence of ENs reentering the run state. When the system chooses to send a packet over the MoCA network, the system may instruct the MoCA node to transition from the standby (M1) to the active (M0) state.

The following description corresponds to the exemplary steps shown in fig. 3. Step 301 shows the EN obtaining an M1 standby to M0 run request from an external source (upper layer of the host entity), i.e., the system in which the node is located.

Step 302 shows EN sending a request to NC requesting node to re-enter the running state by deasserting the bit incorporating its node _ ID into the Standby Vector (SV) information element of its reservation request frame.

Step 303 shows the NC acknowledging the EN transition by deasserting the bit in conjunction with the node _ ID of the requestor into the Standby Vector (SV) information element of the MAP frame.

Fig. 4 shows a schematic diagram of another embodiment of an EN/NC that wants to transmit a frame to an EN in a standby state (as shown in step 401). The following description corresponds to the example steps that are shown in fig. 4.

The EN/NC in operation generally knows that: a) which destination nodes are in standby state (according to the standby node vector (SV) in the MAP frame), and b) the characteristics of the 802.3 frame to be transmitted, e.g., unicast (single node receiver), multicast (multiple preferred receivers), or broadcast (sent to all nodes).

Step 402 shows that for MAC unicast and/or MAC broadcast frames, the requesting EN waits for the bit associated with the destination node ID in the next MAP vector (NV) within the MAP frame to be asserted to send a Reservation Request (Reservation Request) for the transmission pending in its next scheduled RR 403.

For MAC multicast frames, the EN may ignore the standby node, since the standby node is typically not a member of any multicast group. Generally, in the method according to the invention, a node deregisters from any multicast group upon transition to a standby state.

Step 404 shows that the NC may approve the RR in the MAP following the beacon. If the NC is unable to grant a request in the next MAP cycle, the NC may grant a request in a subsequent MAP cycle by instructing a node to receive a subsequent MAP frame. In one embodiment of the invention, the NC may provide the indication by keeping the bit associated with the destination node ID in the next MAP vector (NV) within the MAP frame asserted.

Step 405 shows a transmission to a node in standby mode. The standby mode may be triggered to an active mode or an idle mode to receive any scheduled event in the standby state and may be triggered to the idle mode before the scheduled event. The beacon indicates the event that the MAP frame is scheduled. The standby node may then receive the MAP frame and parse it.

If there are more transmissions pending, the NC may schedule the transmission in the MAP period immediately following the first MAP of the beacon transmission by keeping the bit associated with the receiving standby node in the next MAP vector (NV) within the MAP frame asserted.

Certain aspects of the present invention relate to transmission and NC MoCA node processing in a hybrid MoCA network of nodes in standby and active states.

A running node may send three types of MAC frames: unicast, multicast, and broadcast.

It should be noted that the extraction of the MAC address type of the IEEE 802.3 incoming frame is supported by device hardware and software readable to the requesting party.

The following table lists all possible transmission scenarios and their corresponding TX and NC processing according to one embodiment of the invention.

Watch 10

Another aspect of the invention relates to an NC entering a standby state. The NC that is entering the standby state should first initiate an NC switch with one EN running in the network. If the NC is the next node in the network to operate, it should enter its standby state and:

(1) extend its MAP period to send only one (or two to offset time) MAP per beacon period (every 10ms, nominal, or other suitable duration); and/or

(2) The NC may also enter the run state at this point whenever a node on the network instructs it to enter the run state again.

Yet another aspect of the invention relates to a system, referred to herein as "wake on MoCA (WoM)".

Table 11 describes WoM mode filtering for MoCA nodes.

TABLE 11WOM frame Filtering mode

MAC address resolution preferably provides IP address to MAC address translation. Using IPV6, the multicast MAC DA (destination address) allows a node to be virtually connected even if the node is in a standby state. Such a protocol may be implemented by signaling the receipt of some specific network protocol frame to the system in standby state. Such signaling causes the system to wake up and acknowledge these frames, thereby preventing its respective network or transmission protocol from timing out. Such IP-specific frames may include 802.3 unicast frames, IPV4ARP frames, and/or IPV6IGMPv6 network discovery neighbor/route request and update message frames. Such techniques preferably eliminate the need for power management proxy servers and/or proprietary protocols in accordance with the present invention.

FIG. 5 illustrates an exemplary embodiment of a system that may use the methods described herein to reduce power consumption in a MoCA network. Fig. 5 preferably has a first TV display 502, a first set-top box (STB)504, a second TV display 506 and a second set-top box 508. The first set-top box 504 and the second set-top box 508 may be connected by a coaxial cable network 510.

First set-top box 504 has a local memory 512. The local storage may store the movie on a hard disk or other suitable storage medium. Each set-top box 504 and 508 (or just the first set-top box 504) is capable of supporting soft OFF, which will replace the set-top box in a standby state according to the present invention. The soft OFF button may be provided on a panel of the set-top box or the infrared remote controller.

In one embodiment of the invention, the first set-top box 504 may be in a standby state. In this embodiment, the second set-top box 508 may access the hard disk on the first set-top box 504, for example, to play a movie stored in the hard disk 512 of the first set-top box 504 on the second TV display 506, even if the first set-top box 504 is in a standby state.

Fig. 6 shows a schematic diagram of the operation of the standby state according to the present invention. Fig. 6 shows that a standby node 602 according to the invention can be characterized such that the set-top box remains active by listening for a beacon 604 and a first MAP after the beacon. The relative time of the next MAP may be indicated in the beacon sent by the NC at the absolute time.

According to the invention, the rules associated with the standby nodes are as follows: the standby node may always be listed in a predetermined MAP, e.g., the first MAP after a beacon, and may continue to listen for subsequent MAPs as indicated by the NV vector within the MAP frame, as shown at 608. When the NV vector indicates otherwise, the standby node 602 may not listen for MAPs in the current beacon period or other predetermined beacon period, knowing the first MAP for the next signal period.

Fig. 7 shows another schematic diagram of the operation of the node in the standby state. In fig. 7, after the first beacon 701, the standby node listens only to the first MAP 702 of the beacon period. The standby node then returns to the idle state in response to the deasserted bit within the NM vector.

Following the second beacon 701, the standby node listens to the first MAP 703 and the second MAP 704 in response to the asserted bit in the NM vector of the first MAP 703 for the second beacon period. Thereafter, the standby node returns to the idle state in response to the deasserted bit in the NM vector of the second MAP 704.

Also shown is a beacon 705. It is noted that each MAP before a beacon typically asserts a bit in the NM vector to let the standby node listen to the first MAP after the vector.

The foregoing analysis makes the assumption that, in addition to MoCA, the refresh DDR and ethernet subsystems interfacing with MoCA are ON, which consumes 500 to 600 mW. MoCA is connected but usually idle. Other embodiments of the present invention reduce the power consumption of the ethernet subsystem by waking up the ethernet subsystem in response to an interrupt generated by the MoCA core applying the filtering pattern described above.

Preferably, the present invention can provide remote access through a network in a standby state without requiring any sideband methods or protocols other than TCP/IP. Systems and methods according to the present invention may adapt a MoCA-based product to Energy Star (Energy Star) and comply with EC, may provide remote management capabilities for the MoCA-based product while the product is in a standby state, and may provide the product with the ability to instantaneously return to a fully functional state from a standby state.

In the MoCA1.1 specification, inactive nodes of the opposite network either remain fully active even without activity or are turned off to save power. Re-entry into the network requires a full grant process lasting a few seconds.

Several organizations, including the EC (european commission) and Energy Star organization (Energy Star) in the united states, are writing recommendations to reduce total Energy consumption in the home. Set-top boxes, digital televisions, and other video/network devices are all contemplated. In particular, their recommendations include a recommendation for an energy efficient standby state of the set-top box, since these devices are inactive most of the time.

Networked devices, such as networked set-top boxes, should keep their network active even when they are in a power-saving mode in order to be able to wake up remote nodes. Both energy star and EC provide suggestions for networked devices that are in standby state but need to keep their network active.

Fig. 8 shows a schematic diagram of the power dependency for network devices within a system according to the invention. In particular, FIG. 8 shows the coupling between a memory module 802, a bus 804, a legacy NIC (network interface controller) 806, and a MoCA NIC 808 in accordance with the present invention. In order for NICs 806 and/or 808 to function, the NICs need to be able to be stored within memory module 802 and also be able to be separated from memory module 802. Additionally, to enable communication between NICs 806 and/or 808 and memory 802, bus 804 should be powered.

When the NIC transitions to an active state, it typically immediately begins transmitting data. Thus, to transition from the standby state to the active state, the memory 802 and bus 804 must first be powered up before the NICs 806 and/or 808 are powered up.

Step 902 shows that an M1 Power State request (Power State request) is directed from the host to the MoCA adapter of MoCA node 902. Thereafter, WoM filtering is performed to determine if a wake-up signal from the host internal controls is included in the power state request, as shown in step 904. The wake-up signal is used to indicate to the system the receipt of a frame of interest to the system (which the upper network protocol of the frame should process and reply to prevent the protocol from timing out). As a result of the wake-up signal, the system may first power the system modules that need to receive the frame reserved by the MoCA device (e.g., power the memory, and then the data bus connected to the MoCA device to transition from the B1 to the B0 state), as shown at 906 and 908. After this sequence is completed (based on the power dependency described in fig. 8), the MoCA device is requested to re-enter M0 power from M1 power in step 910. In step 912, the MoCA device has entered the M0 state and is able to transmit the received frame to system memory for processing by higher level entities.

Another aspect of the invention relates to power management messages. A power management MoCA Management Protocol (MMP) message in accordance with the present invention can be sent by a host to request a MoCA node to transition from one power mode state to another. The message includes:

a run state (M0) to a sleep state (M1);

an operating state (M0) to a shutdown state (M3); and

sleep state (M1) to run state (M0).

The MoCA core responds to the transition request indicating the state of the transition. If the transition is successfully completed within the MoCA processing core (i.e., the processing module associated with the MoCA function), the response returns a success status. Otherwise, the response returns a reject status and the reason for the rejection.

The MoCA wakeup frame from the host system may trigger a transition request for the MoCA core from a standby state (M1) to a run state (M0).

FIG. 10 illustrates a schematic diagram of active standby/idle standby mode transitions for a MoCA node participating in periodic Link Maintenance Operations (LMOs) in accordance with the present invention. Lines 1002, 1004 illustrate the transitions of a node in a standby state while participating in an LMO. Timeline 1006 shows that when another node assumes the location of the LMO, the standby node need only be in active mode for time periods 1010 and 1012. It is noted that during time period 1010 (which is shown enlarged at 1008), the standby node need only be active for a probing period (probe) and provide a probing report. Placing the standby node in an idle state during a waiting period (latency period) may additionally save power. The time between each probe is typically 20-350 milliseconds plus a latency (for beacon synchronization) of about 10 milliseconds. Finally, the standby node should remain active during LMO GCD (great Common sensitivity period), during which scheduling the active/idle time of the standby node becomes very complicated.

When the M1 node assumes the location of the LMO node, the LMO is in active mode for the entire LMO process (triggering to idle mode results in insignificant power savings in terms of the active/idle mode ratio during the LMO node sequence).

The time interval between each probe is typically 20-350 milliseconds plus a latency (for beacon synchronization) of about 10 milliseconds.

In some embodiments of the present invention, the NC may select an M1 node as the LMO node at the reduced cycle. For example, in a network with only two nodes, the NC may select the M1 node at the same cycle that exists in a 16-node network. When the M1 node is selected as the LMO node, the M1 node may be at ON. during the entire LMO sequence when the M1 node is selected as the "other node," the M1 node may be fully involved in the LMO in the ON/IDLE mode to minimize power consumption.

Yet another aspect of the present invention relates to a power management protocol Information Element (IE). The Standby Vector (SV) protocol information element may be added to:

1. a reservation request frame, as a request to transition to a standby state by EN, or a request to transition to an active state. This request may be initiated by the host requesting the node to transition from the running state (M0) to the standby state (M1) or vice versa from the standby state (M1) to the running state (M0). To trigger such a request, a node may assert a bit within the standby vector that is associated with its node ID.

2. MAP frame, indicating by the NC the power of each node to all nodes of the MoCA network. An asserted bit within the standby vector indicates that the node with the associated node ID (node ID) is in a standby state. The deasserted bit indicates that the node with the associated node _ ID is in an operational state.

The next MAP vector (NV) protocol information element may be added to: MAP frame of NC to:

1. all the operational nodes in the MoCA network are informed whether a reservation request to the standby node can be made in the next scheduled RR. The asserted bit in the next MAP vector indicates that a reservation request to be made to a node with an associated node ID can be made in the next scheduled RR. The deasserted bit indicates that a reservation request transmitted to the node with the associated node _ ID cannot be made.

2. The selected standby nodes are informed that they should be reactivated in time to receive the next scheduled MAP frame. The asserted bit within the standby vector indicates that the node with the associated node _ ID should receive the next MAP frame. The deasserted bit indicates that the node with the associated node _ ID will no longer receive a MAP frame during the current beacon period.

Table 12 gives examples of the standby vector protocol information element and the next MAP vector protocol according to the present invention.

Table 12 standby vector protocol information element

Network management of nodes in standby state

Link Management Operations (LMO)

The NC should reduce the frequency with which it selects the standby node as the "LMO node". The LMO node is typically used to determine the GCD (maximum common Density period). Link management protocols are commonly used in many types of networks to maintain control channel connectivity, verify physical connectivity of data links, correlate link attribute information, suppress downstream alarms, and localize link failures for protection/repair purposes.

According to the invention, the nodes in standby state can participate in all MoCA network management protocols (LMO, topology upgrade, confidentiality and the like) like the running nodes. There is a difference in the standby state. The node in the standby state need not be selected as an LMO node (master node or LMO) at the same frequency as the node in the running state. Conversely, a node in a standby state may remain in an active mode during the time it is a selected LMO node and may switch between active and idle modes when it is a slave to another LMO mode. Details of the operation of the LMO node according to the present invention are given in the description corresponding to FIG. 10.

FIG. 11 illustrates a single chip or multi-chip module 1102, which may be one or more integrated circuits, within an exemplary data processing system 1100 in accordance with the present invention. The data processing system 1100 may have one or more of the following components: I/O circuitry 1104, peripherals 1106, processor 1108, and memory 1110. These components are connected to each other via a system bus or other interconnect 1112 and are disposed on a circuit board 1120 that is included in an end user system 1130. System 1100 may be configured for a cable television tuner according to the present invention. It is noted that system 1100 is merely an example, and that the true scope and spirit of the invention should be defined by the claims.

Systems and methods for providing MoCA power management policies are described above.

Various aspects of the present invention have been described in connection with specific embodiments thereof. It will be apparent to those skilled in the art that numerous other embodiments, modifications and variations exist which still fall within the scope and spirit of the invention as defined in the claims. For example, those skilled in the art will appreciate that the steps illustrated in the figures may be performed in an order other than that shown, and that one or more of the steps may be optional. The methods and systems of the above embodiments may also have other additional elements, steps, computer-executable instructions, or computer-readable data structures. In this regard, other embodiments are also disclosed herein and may be partially or fully implemented on a computer-readable storage medium, for example, by storing computer-executable instructions or modules or by utilizing computer-readable data structures.

Claims (8)

1. A network employing coaxial cables, the network comprising:

a network controller;

a plurality of network nodes, each network node comprising an integrated circuit, each integrated circuit comprising a plurality of circuit modules;

wherein each of the network nodes is configured to be in:

an operating power state; and

a standby power state including an active mode and an idle mode; and wherein

In the active mode, the network node is configured to transmit and/or receive information data packets; and

in the idle mode, the network node is configured to remain connected to the network while powering down a portion of the circuit modules, thereby reducing power consumption of the network node,

wherein each of said network nodes is adapted to power down two of said circuit blocks by gating a physical system clock signal generated by a multimedia over coax alliance core, MoCA, provided to a digital PHY layer circuit block and gating a system clock signal generated by said MoCA core provided to a MAC layer circuit block; and

in the idle mode, a network clock signal generated by the MoCA core is provided to a CPU circuit block and the MAC layer circuit block of each of the network nodes, wherein the MoCA core operates continuously.

2. The network of claim 1, wherein each of the network nodes is configured to switch from an idle mode to an active mode following a network beacon signal.

3. The network of claim 1, wherein each of the network nodes is configured to receive an interrupt signal over a link to the network.

4. The network of claim 1, wherein the portion of the circuit block comprises a clock portion that provides the physical system clock signal to a digital PHY layer.

5. The network of claim 1, wherein the portion of the circuit module includes a clock portion that provides the system clock signal to a multimedia access controller layer.

6. A method of communicating between a plurality of network modules over a coaxial cable backbone in a home network, wherein the home network comprises the plurality of network modules, one of the plurality of network modules is a network controller, the plurality of network modules comprises network nodes, each of the plurality of network modules is connected to a coaxial cable backbone; the method comprises the following steps:

receiving, using the network controller, a request for broadband transmit pulses from the plurality of network modules, the request being transmitted over a coax backbone;

establishing a sequence of transmit opportunities for the plurality of network modules to track when pulses are transmitted directly to other network modules through the coax backbone; and

triggering, using the network controller, each network module between a run power state and a standby power state, the standby power state including an active mode and an idle mode; wherein:

in the active mode, the network node is configured to transmit and/or receive information data packets; and

in the idle mode, the network node is configured to remain connected to the network while powering down a portion of the circuit modules, thereby reducing power consumption of the network node,

wherein each of said network nodes is adapted to power down two of said circuit blocks by gating a physical system clock signal generated by a multimedia over coax alliance core, MoCA, provided to a digital PHY layer circuit block and gating a system clock signal generated by said MoCA core provided to a MAC layer circuit block; and

in the idle mode, a network clock signal generated by the MoCA core is provided to a CPU circuit block and the MAC layer circuit block of each of the network nodes, wherein the MoCA core operates continuously.

7. The method of claim 6, further comprising switching a network module from an idle mode to an active mode after a network beacon signal.

8. The method of claim 6, further comprising configuring a network module to receive an interrupt signal over a link to the network.