CN114978787A - Power off of power over Ethernet interface - Google Patents

Abstract

Examples described herein relate to improving power down of a PoE interface in a network device. In response to detecting a fault interrupting power flow from the PSU to the one or more PoE interfaces, examples determine a total operable power value based on the operable power values of each of the operable PSUs in the PSU and determine a total available power value based on the total operable power value and the reserved power value. For each PoE interface, the example determines whether the threshold power value of the PoE interface exceeds the total available power value, and powers down the PoE interface in response to determining that the threshold power value of the PoE interface exceeds the total available power value.

Description

Power off of power over Ethernet interface

Cross Reference to Related Applications

This patent application is related to co-pending application serial No. 17/179638 filed on 19/2/2021, which is incorporated herein by reference.

Background

Power over ethernet (PoE) allows ethernet cables to be used for both power and data transmission. Devices such as voice over internet protocol (VoIP) phones, Light Emitting Diode (LED) lights, Internet Protocol (IP) cameras, wireless Access Points (APs), and Bluetooth Low Energy (BLE) beacons may be powered by PoE and, therefore, may be installed in locations that are impractical or expensive to install conventional wires for powering. There are several industry standards for PoE devices. For example, the Institute of Electrical and Electronics Engineers (IEEE) defines at least three industry standards: IEEE802.3 af, which allows up to 15.4 watts of power to be delivered over a class 5 (Cat5) Ethernet cable; IEEE802.3at, which allows up to 30 watts of power to be delivered over Cat5 cables; and IEEE802.3 bt, which allows up to 71.3 watts of power to be delivered over Cat5 cables. LTPoE + + (proprietary standard) allows up to 90 watts of power to be delivered over Cat5 cables. In the IEEE standard, a device receiving PoE is referred to as a Powered Device (PD), and a device providing PoE is referred to as Power Sourcing Equipment (PSE).

Drawings

Various features and advantages of the invention will become apparent from the following description of examples of the invention, given by way of example only, with reference to the accompanying drawings, in which:

fig. 1 is a block diagram of a network device for powering down a PoE interface, according to an example.

Fig. 2 is a flow diagram of a method for powering down a PoE interface, according to an example.

Fig. 3 is a block diagram of a system for powering down a PoE interface according to an example.

Fig. 4 is a flow diagram of a method for powering down a PoE interface, according to another example.

Fig. 5 is a block diagram of a computer system in which various examples described herein may be implemented for powering down a PoE interface, according to an example.

Detailed Description

The following detailed description refers to the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings and the following description to refer to the same or like parts. It is to be expressly understood, however, that the drawings are for the purpose of illustration and description only. While several examples are described in this document, modifications, adaptations, and other implementations are possible. The following detailed description, therefore, does not limit the disclosed examples. Rather, the proper scope of the disclosed examples can be defined by the appended claims.

The terminology used herein is for the purpose of describing example embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The term "plurality", as used herein, is defined as two or more than two. The term another, as used herein, is defined as at least a second or more. As used herein, unless otherwise indicated, the term "coupled" is defined as connected, whether directly without any intermediate elements or indirectly through at least one intermediate element. Two elements may be mechanically coupled, electrically coupled, or communicatively linked through a communication channel, pathway, network, or system. As used herein, the term "and/or" refers to and encompasses any and all possible combinations of one or more of the associated listed items. It will be further understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms, as these terms are only used to distinguish one element from another unless otherwise specified or the context indicates otherwise. As used herein, the term "includes" means including but not limited to, the term "including" means including but not limited to. In some instances, the presence of broad words and phrases such as "one or more," "at least," "but not limited to," or other like phrases, is not to be construed as referring to the narrower case that such broad phrases may not be present.

In an industrial network deployment, such as an enterprise network, campus network, or Data Center Network (DCN), several devices may be connected to the network via a network device (e.g., an ethernet switch). A network device may provide PoE for power and data transmission (referred to herein as "PoE power and data transmission") to several PDs. While a single PD may consume a relatively small amount of power delivered via a PoE interface (e.g., an ethernet port), PDs in a network may collectively consume a large amount of power in terms of cost and percentage of the total power used by devices in the network. In some cases, the total amount of power required by such a PD is much greater than the amount of power required by the network device to provide data networking functions (e.g., switching, routing) to the network.

When a network device providing PoE power and data transmission to a PD loses power provided by one or more Power Supply Units (PSUs) due to a fault and/or power interruption (hereinafter collectively referred to as a "power failure event"), the network will likely experience sudden downtime if the aggregate power load used by the PD and the network device meets the total power output capacity of the remaining operational (i.e., non-faulty) PSUs. This downtime may cause certain types of PDs to lose power and data transmission altogether, which may be expensive for applications requiring high reliability PoE power and data transmission.

To facilitate improving reliability of PoE power and data transmission during a power failure event, the network device may be configured for PSU redundancy to receive backup power from one or more independent PSUs that retain power for use during the power failure event. However, such PSU redundancy may force a trade-off between power redundancy and total power output capacity, as the total amount of available power decreases as more power output capacity is reserved as redundant power via the redundant PSU. Moreover, such PSU redundancy may protect at most several PSUs configured as redundant and may not easily allow PSUs with different power output capacities to be used together to power network devices.

Also, some network devices use: fast power down (RPD), a technique to quickly power down a predetermined number of PoE interfaces during a power failure event; or multi-priority fast power down (MPRPD), which is a technique for quickly powering down a predetermined number of PoE interfaces based on the power output capacity of a failed PSU (i.e., a failed PSU). While these techniques may allow the network device to continue to operate certain high priority PoE interfaces and data networking functions, such techniques may not support multiple fault conditions, i.e., when more than one PSU fails during a power failure event and/or when multiple power failure events occur. Also, in some cases, these techniques may power down more of the PoE interface than is needed to avoid network down time when the power output capacity of a failed PSU is below the operational (i.e., non-failed) PSU. Furthermore, when a PSU failure occurs, such RPD techniques may require software-based communication between the PSU management subsystem on the fail-safe power supply and the PoE management subsystem, which may lead to more complex development and verification tests and increased latency between the PSU management subsystem and the PoE management subsystem.

One or more examples described herein provide improved PoE interface power down and more efficient PSU power utilization compared to the prior art. The examples may determine an amount of power that may be provided from the plurality of PSUs to the plurality of PoE interfaces in response to detecting a fault that interrupts power flow from the PSUs to one or more PoE interfaces. The amount of available power may be determined by considering a complete loss of power due to the fault and the amount of power provided to one or more support components (e.g., line cards, management modules, etc.) of the network device. In this manner, the examples accurately and efficiently determine the total available power that may be provided to the PoE interface. Additionally, examples described herein can identify one or more PoE interfaces that can be powered down based on a threshold power for each PoE interface and power down the one or more PoE interfaces without requiring software-based communication between a PSU management system on a fail-safe power supply and the PoE management system, thereby simplifying the power down process for the PoE interfaces and reducing latency.

In some examples, a method for powering down a PoE interface of a network device is presented. The network device may include a plurality of PSUs that provide power to a plurality of PoE interfaces and one or more support components of the network device. The method may include setting a reserve power value for the network device. In response to detecting a fault interrupting power flow from a plurality of PSUs to one or more of the plurality of PoE interfaces, the method may include determining a total operable power value based on operable power values of each operable (i.e., non-faulty) PSU of the plurality of PSUs, and then determining a total available power value based on the total operable power value and a reserved power value of the network device. The method may comprise, for each of the plurality of PoE interfaces: determining whether a threshold power value of the PoE interface exceeds a total available power value, and in response to determining that the threshold power value of the PoE interface exceeds the total available power value, powering down the PoE interface.

Referring now to the drawings, fig. 1 depicts a block diagram of a system 100 for facilitating power down of a PoE interface in some examples. System 100 includes a network device 110. Additionally, system 100 includes a network 102 coupled to network device 110 and a plurality of PDs 150.

Network device 110 includes at least one processing resource 111 and at least one machine-readable storage medium 112 that includes (e.g., is encoded with) a set reserve power value instruction 114, a determine total executable power value instruction 115, a determine total available power value instruction 116, and a power down instruction 117. The network device 110 may include one or more managed switches that support data link layer switching (i.e., layer 2 or L2 switching), IP layer routing (i.e., layer 3 or L3 routing), or a combination thereof. Moreover, network device 110 may include one or more stackable or independent type switches, modular or fixed configuration type switches, or the like. It should be understood that network device 110 may include one, two, or any suitable number of switches, and may include any suitable type(s) of switch now known or later developed. Additionally, network device 110 may participate in any network data transfer operation, including but not limited to switching, routing, bridging, or a combination thereof.

In fig. 1, network device 110 may operate as a PSE for PD 150. The network device 110 may be configured (e.g., encoded with instructions executable by the at least one processing resource 111) to receive network request(s) 104 from the network 102 via the network path(s) 106 to establish or terminate PoE power and data transfer with one or more PDs 150. Network path(s) 106 may include any suitable link(s) 108 (e.g., wired or wireless, direct or indirect, etc.) between network device 110 and network 102. Network request(s) 104 may include any suitable instructions for instructing network device 110 to establish or terminate PoE power and data transfer with one or more PDs 150. For example, network request(s) 104 may include instructions for instructing network device 110 to perform one or more of set reserve power value instruction 114, determine total operable power value instruction 115, determine total available power value instruction 116, and power down instruction 117.

Network 102 may include one or more Local Area Networks (LANs), virtual LANs (vlans), Wireless Local Area Networks (WLANs), Virtual Private Networks (VPNs), Wide Area Networks (WANs), the internet, and the like or combinations thereof. As used herein, a "wide area network" or "WAN" may include, for example, a wired WAN, a wireless WAN, a hybrid WAN, a software-defined WAN (SD-WAN), or a combination thereof. Also, in some examples, network 102 may include one or more cellular networks using one or more mobile communication standards (e.g., 4G, 5G, etc.). Moreover, although fig. 1 shows a single network device 110 connected to network 102, it should be understood that any suitable number(s) of network devices (other than network device 110) may be connected to network 102.

In fig. 1, PD 150 may include any suitable type(s) of device that may receive PoE from network device 110. For example, PD 150 may include one or more VoIP phones, LED lights, IP cameras, wireless AP or BLE beacons, or a combination thereof. It should be understood that system 100 may include any suitable number of PDs 150. Moreover, it should be understood that PD 150 may receive PoE power and data transmissions in compliance with any suitable type(s) of industry ethernet standard as described herein.

Additionally, network device 110 may be connected to one or more networks and may collect network operation information from various nodes of the one or more networks, including network traffic load information, network topology information, network usage information, and the like. Further, network device 110 may transmit commands to various nodes of the one or more networks to alter network topology and routing to achieve various network efficiency and efficacy goals. It should be understood that network device 110 may include any suitable type(s) of computing device(s) for establishing or terminating PoE power and data transmissions via one or more PoE interfaces. Moreover, network device 110 may include any necessary hardware components for performing the functions disclosed herein, including but not limited to: processors, memory, display devices, input devices, communication devices, and the like.

In examples described herein, a "network path" may include a combination of hardware (e.g., interfaces, links, etc.) and instructions (e.g., executable by a processing resource) to communicate (e.g., receive, send) a command (e.g., network request(s) 104) to an external resource (e.g., server, cloud computing resource, etc.) connected to network 102.

In fig. 1, the network device 110 may be coupled to a plurality of Power Supply Units (PSUs). The network device 110 may include a chassis that includes the PSU 120. Also, the PSU120 may be fixed in the chassis of the network device 110, or alternatively, the PSU120 may be removably attached to the chassis of the network device 110. Although fig. 1 shows the PSU120 included in the network device 110, it should be understood that in some examples, the PSU120 may be external to the network device 110.

Two or more PSUs 120 may have different power output capacities (e.g., one PSU may have a power output capacity of 2 kilowatts, while another PSU may have a power output capacity of 3 kilowatts). It should be understood that the network device 110 may be coupled to two, four, or any suitable number of PSUs. The network device 110 may include one or more redundant PSUs, which may provide backup power when one or more other PSUs of the network device 110 experience a failure (e.g., due to a power failure event). Also, each PSU120 may be configured to continue to provide rated power for a period of time after losing power from the input power source. For example, each PSU120 may be configured to provide rated power for at least a period of time required for the processing resources 111 to execute one or more of the set reserve power value instruction 114, the determine total executable power value instruction 115, the determine total available power value instruction 116, and the power down instruction 117.

In fig. 1, network device 110 may be coupled to a plurality of PoE interfaces 140. Network device 110 may operate as a PSE to provide PoE to PD(s) 150 coupled to PoE interface 140 via PoE interface 140. Each PoE interface 140 can receive power from one or more PSUs 120. Further, each PoE interface 140 can include an ethernet connection (e.g., an ethernet port). The ethernet port may include any suitable physical interface circuitry and/or media-related interface for providing PoE to a PD 150 coupled to the ethernet port. Network device 110 may include a chassis including PoE interface 140. Also, the PoE interface 140 can be fixed in the chassis of the network device 110. Alternatively, PoE interface 140 can be removably attached in a chassis of network device 110. For example, PoE interface 140 can be coupled to one or more line cards that are coupled to network device 110. The one or more line cards may be fixed in the chassis of network device 110, or alternatively, the one or more line cards may be removably attached to the chassis of network device 110. It should be appreciated that network device 110 may be coupled to any suitable number of PoE interfaces, as well as any suitable number of line cards that are each coupled to any suitable number of PoE interfaces. It should be appreciated that the network device 110 and PoE interface 140 can provide PoE power and data transmission in accordance with any suitable type(s) of industry ethernet standard now known or later developed. For example, network device 110 and PoE interface 140 can provide PoE power and data transfer compliant with one or more of IEEE802.3 af, IEEE802.3at, IEEE802.3 bt, and LTPoE + +.

In fig. 1, network device 110 may include one or more support components 130. Support component(s) 130 of network device 110 may facilitate connection to and/or provide support to various elements of network device 110 for their proper functioning. Examples of support component(s) 130 may include fabric(s), backplane(s), line card(s), management module(s), display card(s), fan(s), and the like. Network device 110 may include a chassis that includes support component(s) 130 therein. In some examples, support component(s) 130 may be removably attached to a chassis of network device 110. Each support member 130 may receive input power via an input power source (e.g., a power distribution unit).

In the example of fig. 1, network apparatus 110 may be configured (e.g., encoded with instructions executable by at least one processing resource 111) to provide power from PSU120 to POE interface 140 and support component(s) 130. In some examples, each PoE interface 140 and support component(s) 130 can receive input power from PSU120 via an input power source (e.g., a power distribution unit).

The network device 110 may be configured (e.g., encoded with instructions executable by the at least one processing resource 111) to send or receive data/power signal(s) 170 via data/power path(s) 160 to establish or terminate PoE power and data transfer with one or more PDs 150. Data/power path(s) 160 may include any suitable link(s) 162 between network device 110 and one or more PDs 150. For example, link(s) 162 may include one or more ethernet cables. The data/power signal(s) 170 may include any suitable instructions for causing the network device 110 to establish or terminate PoE power and data transfer with one or more PDs 150 (e.g., for causing the network device 110 to execute one or more of the set reserve power value instruction 114, the determine total executable power value instruction 115, the determine total available power value instruction 116, and the power down instruction 117).

In examples described herein, a "data/power path" may include a combination of hardware (e.g., interfaces, links, etc.) and instructions (e.g., executable by a processing resource) to communicate (e.g., receive, transmit) commands (e.g., data/power signal(s) 170) with one or more PDs 150.

Network device 110 may perform several functions to power down one or more PoE interfaces 140. The functions performed by network device 110 may be performed by processing resource 111 executing set reserve power value instruction 114, determine total executable power value instruction 115, determine total available power value instruction 116, and power down instruction 117 stored in machine-readable storage medium 112 (e.g., a non-transitory machine-readable storage medium). The functions performed by network device 110 to power down one or more PoE interfaces 140 are described herein by way of the flow diagram of fig. 2 below. Although not shown, in some examples, network device 110 may be encoded with certain additional executable instructions to perform actions as described herein, without limiting the scope of the disclosure.

Referring to fig. 2, a flow diagram depicting a method 200 for powering down a PoE interface is presented in some examples. Although execution of the method 200 is described below with reference to the network apparatus 110 of fig. 1, any suitable PSE apparatus (es) for executing the method 200 may be utilized. Additionally, embodiments of method 200 are not limited to such examples. Although method blocks 202-216 are shown in method 200, method 200 may include other acts described herein. Additionally, although the blocks are shown in order, the blocks depicted in FIG. 2 may be performed at any time in any suitable order. Also, some blocks shown in the method 200 may be omitted without departing from the spirit and scope of the present disclosure.

At block 202, the method 200 may include setting a reserve power value for the network device 110. In some examples, the set reserve power value instruction 114, when executed by the processing resources 111, sets the reserve power value for the network device 110. The reserved power value of the network device 110 may represent a predetermined amount of power reserved for powering the support component(s) 130 of the network device 110 relative to the total power capacity of all PSUs 120. In some examples, the reserved power value of the network device 110 may represent the maximum amount of power that may be provided to the support component(s) 130 relative to the total power capacity of all PSUs 120. The maximum amount of power that may be provided to support component(s) 130 may be the sum of the maximum power requirements of each of support component(s) 130. Setting the reserved power value for the network device 110 may include assigning an unsigned bit value to the support component(s) 130 of the network device 110. Each bit of the reserved power value may correspond to an amount of power that may be provided to the support component(s) 130 of the network device 110. For example, an 8-bit unsigned bit value between 0 and 255 may be assigned as the reserved power value for network device 110. In some cases, if the total power capacity of the PSU120 is 10 kilowatts and the maximum power amount of the support component(s) is 200 watts, then the 8-bit unsigned bit value of the reserve power value is 5. It should be appreciated that the reserved power value of the network device 110 may be an 8-bit unsigned value, a 9-bit unsigned value, a 16-bit unsigned value, or a bit value of any suitable size, and may also include any suitable format(s) (e.g., an unsigned bit value, a signed bit value). The reserved power value of network device 110 may be predetermined by network device 110 or received as input by network device 110 (e.g., received from network 102 via network request 104).

In some examples, method 200 may include setting a threshold power value for each PoE interface 140. In some examples, machine-readable storage medium 112 may include threshold power value instructions that, when executed by processing resource 111, set a threshold power value for each PoE interface 140. The threshold power value for one of the PoE interfaces 140 can represent a threshold (i.e., minimum) amount of power provided to the PoE interface in the form of PoE power and data transmissions based on the power required by one or more PDs 150 coupled thereto. In some examples, the threshold amount of power provided to the PoE interfaces can be further dependent on a priority level of power being provided to the PoE interfaces relative to other ones of the PoE interfaces 140. In some examples, a PoE interface of PoE interfaces 140 that receives a threshold amount of power (e.g., 30 watts) that is lower than a threshold amount of power (e.g., 60 watts) received by another PoE interface of PoE interfaces 140 can be configured to have a higher priority level to receive power than the other PoE interfaces. The priority level at which power is provided to one of the PoE interfaces 140 relative to the other ones of the PoE interfaces 140 can be predetermined by the network device 110 or received as input by the network device 110 (e.g., received from one or more networks via the network request(s) 104).

Setting a threshold power value for each PoE interface 140 can include assigning unsigned bit values for the PoE interfaces 140. For example, an 8-bit unsigned bit value between 0 and 255 may be assigned as the threshold power value for each PoE interface 140. Each bit of the threshold power value for a given PoE interface in PoE interfaces 140 can correspond to a threshold amount (i.e., a minimum amount) of power provided to the given PoE interface based on the power required by one or more PDs 150 coupled to the given PoE interface and the priority level at which the given PoE interface is powered. For example, when a first one of PoE interfaces 140 receives 1000 watts and is configured to have a high priority level to receive power, and a second one of PoE interfaces 140 receives 1000 watts and is configured to have a low priority level, a threshold power value of 25 may be assigned to the first PoE interface and a threshold power value of 50 may be assigned to the second PoE interface. It should be appreciated that the threshold power value of each PoE interface 140 can be an 8-bit unsigned value, a 9-bit unsigned value, a 16-bit unsigned value, or a bit value of any suitable size, and can also include any suitable format(s) (e.g., unsigned bit value, signed bit value). The threshold power value for a given one of PoE interfaces 140 can be predetermined by network device 110 or received as input by network device 110 (e.g., received from network 102 via network request(s) 104).

At block 204, the method 200 may include determining a total operational power value of the PSU120 in response to detecting a fault interrupting power flow from the PSU120 to the one or more PoE interfaces 140. In some examples, the determine total executable power value instruction 115, when executed by the processing resource 111, may determine the total executable power value of the PSU120 in response to detecting the fault. A fault may occur in one or more PSUs 120, which results in a loss of power that may be provided by the PSUs 120. A given PSU may be identified as faulty when its power output capacity is zero (e.g., a full power failure) or less than its predetermined power output capacity (e.g., a partial power failure). In some examples, a fault may be detected in one of the PSUs 120, which may be referred to herein as a 'faulty PSU'. The total operable power value of the PSU120 may be determined based on the operable power values of all operable (non-failed) PSUs in the PSU 120. As used herein, an operable PSU may refer to a PSU that provides power output capacity. The operational ones of the PSUs 120 may be referred to herein as 'operational PSUs 120'. The operable power value of an operable PSU may represent a ratio of the power output capacity of the operable PSU to the total power output capacity of all operable PSUs 120. Setting the operable power value for each operable PSU120 can include assigning an unsigned bit value to the operable PSU. For example, an 8-bit unsigned value between 0 and 255 may be assigned as the operable power value for a given operable PSU. In some examples, when the network device 110 is coupled to two operable PSUs 120 each having the same power output capacity (e.g., 1 kilowatt), each of the two operable PSUs 120 may be assigned an 8-bit unsigned value 127 as the operable power value to indicate that the power output capacity of each of the two operable PSUs 120 is half of the total power output capacity of the two operable PSUs 120 (represented as an 8-bit unsigned value 255). Each bit of the operational power value may correspond to an amount of power that may be provided to one or more PoE interfaces 140 coupled to the network device 110 and to the support component(s) 130 of the network device 110. For example, when the network device 110 receives power from an operable PSU120 having a total power output capacity of 10 kilowatts, and when the operable power value is represented as an 8-bit unsigned value (i.e., a value representing 255 levels), each level of the operable power value may correspond to 39.215 (i.e., 10 kilowatts/255) watts of power that may be provided by the network device 110 to the support component(s) 130 and the PoE interface(s) 140. In some examples, the operable power value of a given one of the PSUs 120 indicates the amount of power lost when the given PSU fails. Alternatively, the operable power value of the PSU may correspond to a null power value (e.g., an unsigned 8-bit value of 0), such that the operable power value indicates that the given PSU has no power output capacity at the time of the fault.

At block 204, the method 200 may include summing the operable power values of all operable PSUs 120 to determine a total operable power value. In some examples, the determine total executable power value instructions 115 may include instructions for summing the executable power values of all of the executable PSUs 120 to determine a total executable power value. The addition of the operable power values of all operable PSUs 120 may be performed via an adder circuit. For example, the determine total operable power value instruction 115 may include instructions for receiving operable power values of all operable PSUs 120 as input values by an adder circuit and adding the received operable power values by the adder circuit to determine the total operable power value. The adder circuit for calculating the total operable power value may include a plurality of adders (e.g., multi-stage adders). The addition of the operable power values of all the operable PSUs 120 may be performed synchronously or asynchronously. For example, the operable power values of all operable PSUs 120 may be added simultaneously via an adder circuit. In other cases, the operable power values of two or more of the operable PSUs 120 may be added to determine an intermediate operable power value, and then the operable power value of each of the other operable PSUs 120 may be added to the intermediate operable power value to determine a total operable power value. In some examples where the operable power value of the failed PSU is empty, the determine total operable power value instruction 115 may include instructions to sum the operable power values of all PSUs 120 to determine the total operable power value. It should be appreciated that adder circuit may include one, three, or any suitable number of adders, and that adder circuit may include one or more half-adders, full-adders, ripple carry adders, carry-lookahead adders, carry-save adders, or any suitable type(s) of adders. It should be appreciated that the adder circuit may be integrated into one or more devices (e.g., chips) as an integrated circuit and/or any other suitable hardware.

At block 206, the method 200 may include determining a total available power value based on the total operable power value and the reserve power value. The total available power value may represent the total available power for PoE (i.e., the total available power for PoE interface 140). In some examples, the determine total available power value instruction 116, when executed by the processing resource 111, may determine the total available power value. The total available power for PoE may represent the amount of power available to PoE interface 140 based on the total amount of power received from operational PSUs 120. In some examples, the amount of available power to be provided to the PoE interface 140 can depend on the total amount of power received from the operational PSUs 120 by accounting for power loss due to the fault (as detected in block 204) and the amount of reserve power that can be used to power the support component(s) 130 of the network device 110. At block 206, determining the total available power value may include subtracting the reserved power value of the network device 110 from the total operable power value. Subtracting the reserve power value from the total operable power value may be performed via a subtractor circuit. For example, determine total available power value instruction 116 may include instructions for receiving the total operable power value as an input value by a subtractor circuit and subtracting a reserve power value from the total operable power value by the subtractor circuit. It should be understood that the subtractor circuit may include one or more half-subtractors, full subtractors or any suitable type(s) of subtractors. It should be appreciated that the subtractor circuit may be integrated into one or more devices (e.g., chips) as an integrated circuit and/or any other suitable hardware.

At block 206, method 200 may further include sending a total available power value to each PoE interface 140. The total available power value may be sent to each PoE interface 140 as an output value of the subtractor circuit via a subtractor circuit (e.g., as described above). Also, sending the total available power value to each PoE interface 140 can be performed synchronously or asynchronously with sending the total available power value to the other PoE interfaces 140. For example, the total available power value may be sent asynchronously (e.g., independently and in parallel and/or simultaneously) to each PoE interface 140.

At block 208, method 200 may perform a check to determine whether the threshold power value of each PoE interface 140 exceeds the total available power value. In some examples, the power down instructions 117, when executed by the processing resources 111, determine whether the threshold power value of each PoE interface 140 exceeds the total available power value. Determining whether the threshold power value of each PoE interface 140 exceeds the total available power value can be performed synchronously or asynchronously with the other PoE interfaces 140. For example, determining whether the threshold power value of each PoE interface 140 exceeds the total available power value can be performed asynchronously (e.g., independently and in parallel and/or simultaneously). At block 208, if it is determined that the threshold power value for a given PoE interface 140 exceeds the total available power value, method 200 proceeds to block 210. At block 208, if it is determined that the threshold power value for a given PoE interface 140 does not exceed the total available power value, the method 200 can return to block 204.

At block 206, determining whether the threshold power value of each PoE interface 140 exceeds the total available power value may be performed individually via a comparator circuit. In some examples, each PoE interface 140 can include a separate comparator circuit that determines whether a threshold power value of the PoE interface exceeds a total available power value. For example, the power down instructions 117 may include instructions for receiving, by each comparator circuit, a total available power value as a first input value, receiving a threshold power value for the PoE interface 140 as a second input value, and comparing the total available power value to the threshold power value for the PoE interface 140. Also, the power down instructions 117 may include instructions for sending, by each comparator circuit, an output value indicating whether the threshold power value of the corresponding PoE interface exceeds the total available power value. For example, each comparator circuit may send a high output voltage value to indicate that the threshold power value of the corresponding PoE interface exceeds the total available power value. Alternatively, the comparator circuit may send a low output voltage value to indicate that the threshold power value of the corresponding PoE interface exceeds the total available power value. Each comparator circuit may receive the total available power value from a subtractor circuit (as described above). It should be understood that each comparator circuit may be integrated into one or more devices (e.g., chips) as an integrated circuit and/or any other suitable hardware.

At block 210, method 200 may include powering down (at block 208) the one or more PoE interfaces 140 for which the determined threshold power value exceeds the total available power value. In some examples, the power down instructions 117, when executed by the processing resources 111, power down the one or more PoE interfaces 140 for which the threshold power value exceeds the total available power value (at block 208). Each PoE interface 140 determined (at block 208) that the corresponding threshold power value exceeds the total available power value can be powered down synchronously or asynchronously with one or more other PoE interfaces 140 determined (at block 208) that the respective threshold power value individually exceeded the total available power value. For example, each PoE interface 140 determined to have a corresponding threshold power value that exceeds the total available power value can be powered down asynchronously (e.g., independently and in parallel and/or simultaneously) with all other such PoE interfaces.

For example, when the reserved power value of the network device 110 is assigned a value of 5 and the total operable power value is determined to be a value of 100, the total available power value is determined to be 95 (i.e., 100-5). In this case, if the threshold power value for a given PoE interface is assigned a value of 100, it is determined that the threshold power value for the given PoE interface exceeds the total available power value (i.e., 100>95), and thus network device 110 powers down the given PoE interface. Also, in another case, if the total operable power value is determined as the value 200, the total available power value is determined as 195 (i.e., 200-5). In this case, it is determined that the threshold power value for the given PoE interface does not exceed the total available power value (i.e., 100<195), and thus network device 110 continues to supply power to the given PoE interface.

At block 210, a power down instruction 117 (as described above) may be implemented using hardware (e.g., a comparator circuit) at each PoE interface 140, such that the PoE interface may be powered down without requiring software-based communication between the PSU management system on the failsafe power supply and the PoE management system.

In fig. 2, method 200 may return to block 204 after powering down one or more PoE interfaces 140 at block 210 to account for power loss due to any subsequent failure of another one of PSUs 120.

In this manner, the examples described herein provide improved PoE interface power down. For example, the network device 110 may determine the total available power value (at block 206) by subtracting the reserved power value of the network device 110 from the total operable power value of the operable PSUs 120, thereby accurately and efficiently determining the amount of power provided to the PoE interface 140 by taking into account the power loss due to one or more failed PSUs in the PSUs 120 and the amount of power that may be provided to the support component(s) 130 of the network device 110. Further, the network device 110 may determine (at block 208) any PoE interface 140 whose threshold power value exceeds the total available power value, and power down (at block 216) that PoE interface, thereby providing only an effective power down of a plurality of PoE interfaces that prevents aggregate power loads (e.g., the total power load of the PD 150 and the network device 110) from exceeding the power output capacity of the operational (i.e., non-faulty) PSU(s) 120. Additionally, network device 110 may include hardware configured to determine whether a threshold power value for a given PoE interface 140 exceeds a total available power value (at block 208) and power down the given PoE interface 140 (at block 216), thus mitigating the need for software-based communications between the PSU management system on the failsafe power supply and the PoE management system to power down the PoE interface and thereby reduce latency. Additionally, the network device 110 determines the total available power value by subtracting the reserve power value from the total operational power value, thereby mitigating the need to adjust the threshold power value of each PoE interface 140 as the amount of power provided to the support component(s) 130 of the network device 110 varies.

Turning to fig. 3, fig. 3 depicts a block diagram of a system 300 for powering down a PoE interface in some examples. The system 300 depicted in fig. 3 may represent one example of the system 100 depicted in fig. 1. Accordingly, the system 300 may include certain features that are similar in one or more aspects (e.g., geometry, dimensions, positioning, material properties, or operation) to similarly-named features of the system 100, the description of which is not repeated herein for the sake of brevity. For example, the system 300 may include a network device 310 coupled to a network 302 and a plurality of PDs 350. Network device 310 may operate as a PSE for PD 350. Network device 110 may be configured to receive network request(s) 304 from network 302 via network path(s) 306 (e.g., via link(s) 308) to establish or terminate PoE power and data transfer with one or more PDs 350. The network device 310 may be configured to send or receive data/power signal(s) 370 via data/power path(s) 360 (e.g., via link(s) 362) to establish or terminate PoE power and data transfer with one or more PDs 350. Network device 310 may include a plurality of PSUs 320, one or more support components 330, and a plurality of PoE interfaces 340. Further, network device 310 may include at least one processing resource 311 and at least one machine-readable storage medium 312 that includes (e.g., is encoded with) a set reserve power value instruction 114, a determine total operable power value instruction 115, a determine total available power value instruction 116, and a power down instruction 117.

In contrast to the system 100 of fig. 1, in an example fig. 3, the network device 310 may include a power distributor 315 coupled between the PSU 320 and the PoE interface 340 to provide power from the PSU 320 to the PoE interface 340. In some examples, where the PSU 320 is external to the network device 310, the power distributor 315 may be implemented external to the network device 310. The power distributor 315 may be configured (e.g., encoded with instructions executable by the at least one processing resource 311) to receive the power signal(s) 384 from the one or more PSUs 320 via the power path(s) 380. The power path(s) 380 may include any suitable link(s) 382 between the PSU 320 and the power distributor 315. Moreover, the power distributor 315 may be configured (e.g., encoded with instructions executable by at least one processing resource) to send or receive data/power signal(s) 394 to one or more PoE interfaces 340 via data/power path(s) 390. The data/power path(s) 390 may include any suitable link(s) 392 between the power splitter 315 and the PoE interface 340.

The power distributor 315 may include a midplane configured to provide power to the support components 130 (e.g., fabric(s), backplane(s), line card(s), management module(s), display card(s), etc.) of the network device 310. The power distributor 315 may include one or more power pads that couple one or more PSUs 320 to the backplane of the network device 310 to provide power to the support component(s) 130 of the network device 310. The power distributor 315 may be configured (e.g., encoded with instructions executable by the at least one processing resource 311) to send or receive power signal(s) 334 to the support component 330 via any suitable link(s) 332. In some cases, the network device 310 may provide power to the PoE interface 340 and support component(s) without the power splitter 315.

Fig. 4 is a flow diagram of a method 400 for providing, by a network device (e.g., network device 110, network device 310), a total available power value to each of a plurality of PoE interfaces and powering down one or more PoE interfaces in some examples. Although execution of method 400 is described below with reference to network device 110 of fig. 1, other network devices suitable for executing method 400 may be utilized. Additionally, embodiments of method 400 are not limited to such examples. Moreover, one or more blocks of method 400 may be performed in conjunction with one or more blocks of method 200. Although only twelve blocks are shown in method 400, method 400 may include other acts described herein. Additionally, although the blocks are shown in order, the blocks depicted in FIG. 4 may be performed at any time in any suitable order. Also, some blocks shown in the method 400 may be omitted without departing from the spirit and scope of the present disclosure.

Referring to fig. 4, at block 412, the network device 110 may detect a failed one of the PSUs 120. A faulty PSU may not be able to provide power output capacity. It should be understood that the method 400 may include additional steps for identifying whether any other of the PSUs 120 has failed. Identifying that a PSU has failed may be performed synchronously or asynchronously while determining whether any other PSU in the PSU120 has failed.

At block 414, in response to detecting the fault, the network device 110 may send the operable power values of all operable (i.e., non-faulty) PSUs (not including the faulty PSU) in the PSU120 to the adder circuit. Sending the operable power value of the operable PSU120 to the adder circuit may include performing one or more steps of block 204 as described above with respect to the method 200 of fig. 2.

Further, at block 414, sending the operable power value of each operable PSU120 to the adder circuit may be performed synchronously or asynchronously with sending the operable power value(s) of one or more other operable PSUs 120. For example, an operational power value of a first operable PSU of the PSUs 120 may be sent to the adder circuit, while an operational power value of a second operable PSU of the PSUs 120 is sent.

At block 416, the network device 110 may determine a total operable power value based on the operable power values of all operable PSUs 120 through the adder circuit. Determining the total operational power value may include performing one or more steps of block 204 as described above with respect to method 200 of fig. 2. For example, at block 416, the network device 110 may include instructions for adding the received operable power values of all operable PSUs 120 by an adder circuit to provide a total operable power value.

At block 418, the network device 110 may perform a check to determine whether the total operable power value is greater than a reserve power value of the network device 110 (described previously). At block 418, if it is determined that the total operable power value is greater than the reserve power value, the method 400 may proceed to block 420. At block 418, if it is determined that the total operational power value is not greater than the reserve power value, the network device 110 may power down all PoE interfaces 140. Powering down all PoE interfaces 140 can be performed synchronously or asynchronously.

At block 420, the network device 110 may send the total operable power value to the subtractor circuit. Sending the total operable power value as the output value of the adder circuit to the input value of the subtractor circuit may include one or more steps of block 206 as described above with respect to method 200 of fig. 2. Also, the network device 110 may send the reserved power value of the network device 110 to the subtractor circuit along with the total operable power value.

At block 422, network device 310 may determine, via a subtractor circuit, a total available power value based on the total operable power value and the reserve power value. Determining the total available power value may include one or more steps of block 206 as described above with respect to method 200 of fig. 2. For example, at block 422, the network device 310 may include instructions for subtracting, by the subtractor circuit, the reserve power value from the total operable power value to provide the total available power value.

At block 424, the network device 310 may send a total available power value to each PoE interface 140. Sending the total available power value to each PoE interface 140 can include one or more steps of block 206 as described above with respect to method 200 of fig. 2. Sending the total available power value to each PoE interface 140 can be performed, for example, via a subtractor circuit. Also, the sending of the total available power value to each PoE interface 140 can be performed synchronously or asynchronously.

At block 426, the network device 110 may perform a check to determine, for each PoE interface 140, whether the corresponding threshold power value (described previously) exceeds the total available power value. Determining whether the threshold power value of each PoE interface 340 individually exceeds the total available power value may include one or more steps of block 208 as described above with respect to method 200 of fig. 2. Determining whether the threshold power value of each PoE interface 140 exceeds the total available power value can be performed synchronously or asynchronously. In some examples, each PoE interface 140 can include a comparator circuit, and determining whether the corresponding threshold power value exceeds the total available power value can be performed individually via the corresponding comparator circuit. At block 426, for each of PoE interfaces 340 for which it is determined that the corresponding threshold power value does not exceed the total available power value, network device 110 may not perform any action as shown in block 428. At block 426, each of PoE interfaces 340 for which the corresponding threshold power value is determined to exceed the total available power value, network device 110 may synchronously or asynchronously power down the PoE interfaces.

Fig. 5 is a block diagram of a computing system 500 that includes, in some examples, processing resources 502 and a machine-readable storage medium 504 encoded with example instructions for powering down a PoE interface of a network device (e.g., network device 110 of fig. 1, network device 310 of fig. 3). As described in detail herein, the machine-readable storage medium 504 may be encoded with executable instructions for performing one or more method blocks of the flowchart 200 of fig. 2 and/or the flowchart 400 of fig. 4, namely a set reserve power value instruction 506, a determine total executable power value instruction 508, a determine total available power value instruction 510, and a power down instruction 512 (hereinafter collectively referred to as instructions 506-512). Although not shown, in some examples, machine-readable storage medium 504 may be encoded with certain additional executable instructions to perform one or more of the method blocks of flowcharts 200 and 400, and/or any other operations performed by network device 110, without limiting the scope of the present disclosure.

The machine-readable storage medium 504 may be non-transitory, and is alternatively referred to as a non-transitory machine-readable storage medium 504. In some examples, the machine-readable storage media 504 may be accessed by the processing resource 502. In some examples, computing system 500 may be included in (e.g., as part of) a network device (e.g., network device 110 of fig. 1, network device 310 of fig. 3). In some examples, the processing resources 502 may represent one example of the processing resources 111 of the network device 110. Further, machine-readable storage media 504 may represent one example of machine-readable storage media 112 of network device 110. In some examples, the processing resource 502 may fetch decode and execute instructions 506-512 stored in the machine-readable storage medium 504 to power down one or more PoE interfaces 140 of the network device 110.

The set reserve power value instruction 506, when executed by the processing resources 502, may set a reserve power value for the network device 110. Further, the determine total runnable power value instructions 508, when executed by the processing resources 502, may determine the total runnable power value in response to detecting a fault that interrupts the flow of power from the PSU120 to the one or more PoE interfaces 140. The determine total available power value instruction 510, when executed by the processing resource 502, may determine a total available power value based on the total executable power value and the reserve power value. Further, the power down instructions 512, when executed by the processing resource 502, may determine, for each PoE interface 140, whether the threshold power value of the PoE interface exceeds the total available power value and power down the one or more PoE interfaces 140 for which the threshold power value exceeds the total available power value.

In general, as used herein, the terms "component," "system," "database," and the like may refer to logic implemented in hardware or firmware, or to a set of software instructions written in a programming language such as, for example, Java, C, or C + +, possibly with entry and exit points. The software components may be compiled and linked into an executable program, installed in a dynamically linked library, or written in an interpreted programming language such as, for example, BASIC, Perl, or Python. It should be understood that software components may be invoked from other components or from themselves, and/or may be invoked based on (e.g., in response to) a detected event or interrupt. The software components configured for execution on the computing device may be provided on a computer readable medium, such as a compact disc, digital video disc, flash memory drive, diskette, or any other tangible medium, or may be provided as a digital download (and may be originally stored in a compressed or installable format that requires installation, decompression, or decryption prior to execution). Such software code may be stored, in part or in whole, on a memory device executing a computing device for execution by the computing device. The software instructions may be embedded in firmware, such as an EPROM. It will be further appreciated that the hardware components may include connected logic units such as gates and flip-flops, and/or may include programmable units such as programmable gate arrays or processors.

In examples described herein, the term "processing resource" may include, for example, one processor or multiple processors included in a single computing system or distributed across multiple computing systems. As used herein, a "processor" may be at least one of a Central Processing Unit (CPU), a semiconductor-based microprocessor, a Graphics Processing Unit (GPU), a Field Programmable Gate Array (FPGA), other hardware devices such as, but not limited to, Integrated Circuits (ICs), control logic, electronic circuitry, or a combination thereof comprising a plurality of electronic components. The processing resources may fetch, decode, and execute instructions stored in the machine-readable storage medium to perform the functions described with respect to the instructions stored on the machine-readable storage medium.

In the examples described herein, the term "machine-readable storage medium" and similar terms refer to any electronic, magnetic, optical, or other physical storage device that contains or stores executable instructions. The machine-readable storage medium may be non-transitory. Common forms of non-transitory machine-readable storage media include, for example, a floppy disk, a flexible disk, a hard disk, a solid state drive, a magnetic tape, or any other magnetic data storage medium, a CD-ROM, any other optical data storage medium, any physical medium with patterns of holes, a Random Access Memory (RAM), a Programmable Read Only Memory (PROM), and Erasable Programmable Read Only Memory (EPROM), a FLASH-EPROM, a non-volatile random access memory (NVRAM), any other memory chip or cartridge, and networked versions of the media.

A non-transitory machine-readable storage medium is different from but may be used in conjunction with a transmission medium. Transmission media participate in the transfer of information between non-transitory media. Transmission media include, for example, coaxial cables, copper wire and fiber optics. Transmission media can also take the form of acoustic or light waves, such as those generated during radio wave and infrared data communications.

As used herein, the term "or" may be interpreted in an inclusive or exclusive sense. Furthermore, the description of a resource, operation, or structure in the singular is not to be construed as excluding the plural. Conditional language (such as "can", "might", "migt", or "may", among others) is generally intended to convey that certain embodiments include (while other embodiments do not include) certain features, elements and/or steps unless specifically stated otherwise, or otherwise understood within the context as used.

While the present technology may be susceptible to various modifications and alternative forms, the examples discussed above are shown by way of example only. It should be understood that the described techniques are not intended to be limited to the particular examples disclosed herein. Indeed, the present technology includes all alternatives, modifications, and equivalents falling within the true spirit and scope of the appended claims.

Claims (20)

1. A method, comprising:

setting a reserved power value for a network device, wherein the network device includes a plurality of Power Supply Units (PSUs) and a plurality of Power over Ethernet (PoE) interfaces that receive power from the plurality of PSUs;

determining, by the network device, a total operable power value based on an operable power value of each operable PSU of the plurality of PSUs in response to detecting a fault interrupting power flow from the plurality of PSUs to one or more of the plurality of PoE interfaces;

determining, by the network device, a total available power value based on the total operable power value and the reserved power value of the network device; and

for each of the plurality of PoE interfaces:

determining, by the network device, whether a threshold power value of the PoE interface exceeds the total available power value; and is provided with

In response to determining that the threshold power value of the PoE interface exceeds the total available power value, powering down, by the network device, the PoE interface.

2. The method as recited in claim 1, wherein the operable power value of each operable PSU of the plurality of PSUs corresponds to a ratio of the power output capacity of the operable PSU to a total power output capacity of the operable PSUs.

3. The method of claim 1, wherein the operable power value of each operable PSU comprises an unsigned bit value assigned to the operable PSU.

4. The method of claim 1, wherein the reserved power value comprises a predetermined amount of power utilized by one or more support components of the network device.

5. The method of claim 1, wherein the reserved power value comprises an unsigned bit value assigned to one or more support components of the network device.

6. The method of claim 1 wherein the threshold power value for each of the plurality of PoE interfaces comprises an unsigned bit value assigned to the PoE interface.

7. The method of claim 1, wherein determining the total operable power value comprises summing, by the network device, the operable power values of each operable PSU of the plurality of PSUs to determine the total operable power value.

8. The method of claim 1, wherein determining the total available power value comprises subtracting, by the network device, the reserve power value from the total operable power value.

9. The method of claim 8, further comprising sending, by the network device, the total available power value to each of the plurality of PoE interfaces.

10. The method of claim 1 wherein determining, by the network device, whether the threshold power value of the PoE interface exceeds the total available power value comprises comparing, by the network device, the total available power value to the threshold power value of the PoE interface.

11. The method of claim 1, further comprising:

determining, by the network device, whether the total operable power value exceeds the reserve power value; and

in response to determining that the total operational power value does not exceed the reserved power value, powering down the plurality of PoE interfaces.

12. The method of claim 1, wherein the plurality of PSUs are configured to provide power to the plurality of PoE interfaces via Power Sourcing Equipment (PSE).

13. The method of claim 1, wherein each of the plurality of PoE interfaces is coupled to a Powered Device (PD) via an ethernet connection.

14. A network apparatus, comprising:

a plurality of Power-over-Ethernet (PoE) interfaces;

one or more support members;

a plurality of Power Supply Units (PSUs) that supply power to the plurality of PoE interfaces and the one or more support components;

at least one processing resource; and

at least one machine-readable storage medium comprising instructions executable by the at least one processing resource to:

setting a reserve power value for the network device, wherein the reserve power value comprises a predetermined amount of power utilized by the one or more support components;

in response to detecting a fault interrupting power flow from the plurality of PSUs to one or more of the plurality of PoE interfaces, determining a total operable power value based on the operable power values of each of the plurality of PSUs;

determining a total available power value based on the total operational power value and the reserve power value of the network device; and

for each of the plurality of PoE interfaces:

determining whether a threshold power value of the PoE interface exceeds the total available power value; and is

In response to determining that the threshold power value of the PoE interface exceeds the total available power value, powering down the PoE interface.

15. The network device of claim 14, comprising:

a power splitter, wherein the plurality of PSUs are configured to provide power to the plurality of PoE interfaces via the power splitter.

16. The network device of claim 14, wherein each of the plurality of PoE interfaces is coupled to a Powered Device (PD) via an ethernet connection.

17. The network device of claim 14, wherein the operable power value of each operable PSU of the plurality of PSUs corresponds to a ratio of the power output capacity of the operable PSU to the total power output capacity of the operable PSUs.

18. The network device of claim 14, wherein the instructions to determine the total operable power value comprise instructions executable by the at least one processing resource to sum operable power values of each of the plurality of PSUs.

19. The network device of claim 14, wherein the instructions to determine the total available power value comprise instructions executable by the at least one processing resource to subtract the reserve power value from the total operable power value.

20. A non-transitory machine-readable storage medium comprising instructions executable by at least one processing resource of a network device to:

setting a reserved power value for the network device, wherein the network device includes a plurality of Power Supply Units (PSUs) and a plurality of Power over Ethernet (PoE) interfaces that receive power from the plurality of PSUs;

setting a threshold power value for each of the plurality of Power-over-Ethernet (PoE) interfaces;

in response to detecting a fault interrupting power flow from the plurality of PSUs to one or more of the plurality of PoE interfaces, determining a total operable power value based on the operable power values of each of the plurality of PSUs;

determining a total available power value based on the total operable power value and the reserved power value of the network device; and

for each of the plurality of PoE interfaces:

determining whether a threshold power value of the PoE interface exceeds the total available power value; and is

In response to determining that the threshold power value of the PoE interface exceeds the total available power value, powering down the PoE interface.

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