CROSS-REFERENCE TO RELATED APPLICATIONSThis application is a continuation of U.S. application Ser. No. 11/535,544, filed Sep. 27, 2006, which claims the benefit of priority to U.S. Provisional Application Ser. No. 60/721,131, filed on Sep. 28, 2005, the subject matter of which is hereby incorporated by reference in its entirety.
BACKGROUNDNetworks that provide power over network cables are attractive because installing a separate power grid is not required when installing equipment having power requirements that may be met by the network connection. Improvements in inserting power into network cables are needed.
SUMMARYA powered patch panel (PPP) is disclosed that is Telecommunication Industry Association (TIA)category 5e and 6 compatible (i.e., supports communications in the gigahertz range), that is compatible with corresponding international standard categories, and that supports power-over-network (PoN) such as power-over-Ethernet (PoE). For example, a PPP may be used in mid-span regions of a network in both cross-connect and interconnect configurations. Thus, the PPP may be incorporated as part of a building permanent link by being directly connected to horizontal cabling. When so incorporated, the building permanent link iscategory 5e and 6 compliant and may support power-over-network (PoN) such as power-over-Ethernet (PoE).
In cross-connect and interconnect configurations that include a patch panel, the PPP may replace the patch panel without requiring additional rack space, provide identical patching flexibility, insert power into network cables, and provide intelligent processing to perform local control and monitoring functions as well as enforcement of network policies.
The PPP may include two power supply input ports so that two power supplies may be used in a fault-tolerant manner to power each PPP. Further, PPP electronics may be separated into at least two power-independent portions, each powered by a separately supplied power-plane. Combined power from the power supply inputs may be converted into at least two independent power outputs that supply power to the two power-planes. One of the power-planes may provide power to a common circuit that includes a processor and supporting hardware while the other power-plane may provide power for a port circuit.
All communications between circuits of the common circuit and port circuit may be power-isolated by either or both optical couplers or capacitors (power isolators), for example, so that power failure in one power-plane does not result in power failure in the other power-plane. In this way, the port circuit and/or common circuit may perform its functions even in the event of power failure in the other circuit. Thus, fault-tolerance may be achieved at the power-plane level.
The PPP may provide powered device (PD) interrogation and power management capabilities. For example, the PPP may detect connection or disconnection of a PD, automatically determine power requirements, and supply power to the PD. Each port may be periodically checked for legacy devices (devices having PoN functionality incompatible with IEEE 802.3af) and accommodated accordingly. In addition, current limiting may be provided for each port.
The PPP may provide LED indicators corresponding to each of the ports. LED functionality may include indication of a PD connection, whether a PD is either an IEEE 802.3af compliant device or a legacy device, and a current limiting condition. Further, LEDs may be controlled to assist in moves, additions, and changes of network cable connections by changing color, turning on or off, and/or adjusting blinking rate.
Other LEDs may be provided to indicate a PPP status and/or a PPP network connection status. For example, an in-line current manager may determine voltage and current input from one or more power supplies and control a PPP LED to indicate conditions such as that the power consumption threshold has been exceeded, the voltage level input is above or below a particular threshold, or the total current output threshold has been exceeded. LED indicators may be provided for an input and an output network connection port.
The input and output network connection ports may support connection of multiple PPPs in a daisy chain configuration. Each of the network ports may be provided with an LED to indicate port status such as connection failure, for example. The daisy chain configuration may provide network connections for devices other than PPPs (such as power supplies) and assist conserving switch port utilization.
Each PPP may include a processor to provide local intelligence for monitoring and controlling PPP ports and to interface with one or more network management systems (NMSs) and/or element management systems (EMSs). On installation, local physical address information such as room number, rack number and/or position in the rack may be entered and saved in a non-volatile memory. Physical address information may also be re-entered when a PPP is reconfigured by changing horizontal cable connections, for example. The processor may upload the local physical address information to the NMS/EMS. Additionally, when PDs are either connected or disconnected, the port status in the non-volatile memory may change. These changes, together with any identifying information, may be automatically reported to the NMS/EMS or stored for later retrieval when requested by the NMS/EMS.
The NMS may provide overall network control and encompass many network devices, while the EMS may be more locally focused. For example, the EMS may be directed to a single PPP, even though it may have access to all network-connected devices. The NMS/EMS may perform functions such as:
- 1. monitoring:
- a. connectivity of the network or a subnet of the network,
- b. power consumption status of a PPP,
- c. connection status of a particular port of a PPP,
- d. power supply status at the PPP and/or at the power supply, and
- e. PPP network connection failure,
- 2. transmitting control parameters to the PPP to control:
- a. setting PPP power consumption level,
- b. prioritize power for each port with low, medium or high priorities,
- c. selectively turning ports on or off based on priorities during power outages or for testing, for example,
- d. activating port LEDs to support moves, additions, and changes of connections,
- e. download software to a PPP for software update; and
- 3. network policy deployment:
- a. security policy,
- b. power consumption and distribution.
The NMS/EMS may include a graphical user interface (GUI) to assist an operator to control and monitor the network. For example, the GUI may display a topology of the complete network, a portion of the network (subnet), or particular unit types such as PPPs of a subnet, for example. The GUI may display all the PPPs of a particular rack and provide information such as location address, MAC address, power consumption, and/or current limiting status of each port of any of the PPPs. In this way, the operator may view one or more statuses only of devices of interest and can efficiently determine the condition of the network or a subnet of the network.
BRIEF DESCRIPTION OF THE DRAWINGSThe invention is described in detail with reference to the following figures wherein like numerals reference like elements, and wherein:
FIG. 1 shows an exemplary network system;
FIG. 2 shows an exemplary building floor plan;
FIG. 3A shows a first conventional LAN cross-connect configuration;
FIG. 3B shows a second conventional LAN cross-connect configuration;
FIG. 4A shows an exemplary PPP LAN cross-connect configuration;
FIG. 4B shows an exemplary PPP LAN interconnect configuration;
FIG. 5 shows an exemplary front perspective view of a PPP;
FIG. 6 shown an exemplary rear perspective view of a PPP;
FIG. 7 shows an exemplary perspective view of a punch-down block;
FIG. 8 shows an exemplary ground strap;
FIG. 9 shows an exemplary rear plan view of three PPPs and a power supply installed within an equipment rack;
FIG. 10 shows an exemplary PPP input power diode circuit;
FIG. 11 shows an exemplary PPP internal Ethernet switch;
FIG. 12 shows an exemplary hardware block diagram of a PPP;
FIG. 13 shows an exemplary block diagram of a current manager;
FIG. 14 shows an exemplary block diagram of a PoE manager;
FIG. 15 shows an exemplary block diagram of an LED manager;
FIG. 16 shows an exemplary PD detection flow chart;
FIG. 17 shows an exemplary legacy device detection flow chart;
FIG. 18A shows an exemplary legacy powered device detector and connected legacy device; and
FIG. 18B shows an exemplary polarity reverse switch.
DETAILED DESCRIPTION OF EMBODIMENTSFIG. 1 shows anexemplary network system100 that supports PoN, such as PoE, and provides network connectivity to end-user devices116-126 (e.g., Voice over IP telephones, computers, etc.), one or more element management systems (EMSs)112 and114, and a network management system (NMS)110 via anetwork104 and local area networks (LANs)106 and108.LANs106 and108 may be connected to network104 vialinks134 and136, respectively;EMSs112 and114 may be connected toLANs106 and108 vialinks130 and132, respectively; andNMS110 may be connected to network104 vialink128.
PoN may be implemented by providing power insertion units such as PPPs inLANs106 and108, for example. In a building installation, PPPs may be disposed in racks such as 19″ racks together with other LAN equipment such as switches, hubs, patch panels, etc. The racks may be placed in an equipment closet where an external network feed enters a building, and LAN switches may be connected to the network feed via a network switch, for example.
FIG. 2 shows anexemplary equipment closet206 of abuilding floor plan200 of building202 forfloor area204. In this example,LAN106 servesfloor2 of building202 andLAN108 servesfloor3 which includes work areas210-214.LAN108 may be connected to network104 via anetwork switch208 that may provide connections to network104 for all LANs ofbuilding202.LAN108 may be coupled to end-user devices122-126 byhorizontal cabling216 via wall jacks218-222 and may deliver power to end-user devices122-126 through jacks218-222.
LANs may have many configurations such as an Ethernet star configuration, for example, that includes an Ethernet switch (switch) that permits communication between end-user devices and/or other networks. In the star configuration, end-user devices may be connected to the switch in a cross-connect configuration or an interconnect configuration.FIG. 3A shows a first conventional LAN cross-connect configuration that uses two conventional patch panels. As shown inFIG. 3A, usingLAN106 as an example, all ports of aswitch230 are connected to aconventional patch panel232 via cables connected from switch ports onswitch230 to punch-down blocks on the back side ofconventional patch panel232. End-user devices116-120 may be directly or indirectly connected to thepatch panel234 via horizontal cabling and punch-down blocks (not shown) on the rear face ofpatch panel234. Connections betweenpatch panel232 andpatch panel234 may be easily established and/or modified by changing patch cord connections between the front face ports ofpatch panel232 and the front face ports ofpatch panel234. Such a cross-connect configuration optimizes the ease and flexibility with which connections between the horizontal cable plant may be established, rerouted, or removed.
FIG. 3B shows a second conventional LAN cross-connect configuration that uses a power hub and a conventional patch panel. As shown inFIG. 3B, usingLAN106 as an example, all ports of aswitch230 are connected to aconventional power hub233 via cables connected from switch ports onswitch230 to a top row of ports onpower hub233. End-user devices116-120 may be directly or indirectly connected to aconventional patch panel234 via horizontal cabling and punch-down blocks (not shown) on the rear face ofpatch panel234. Connections betweenpower hub233 andpatch panel234 may be easily established and/or modified by changing patch cord connections between the lower front face ports ofpower hub233 and the front face ports ofpatch panel234. As addressed above with respect toFIG. 3A, such a cross-connect configuration optimizes the ease and flexibility with which connections between the horizontal cable plant may be established, rerouted or removed.
By includingpower hub233, the cross-connect configuration depicted inFIG. 3B is able to insert PoN power over the respective horizontal cable network connections. However, because both the input ports and the output ports are on the front face of the power hub, the power hub requires twice the vertical space requirements in a standard equipment rack than a conventional patch panel. Therefore, the space requirements of a large network that uses power hubs in a cross-connect configuration are significantly greater than the space requirements of a patch panel-based cross-connect configuration.
The majority of deployed, large scale network infrastructure layouts were designed prior to the widespread acceptance of PoN. Therefore, the majority of deployed cross-connect configurations and the equipment rooms which accommodate those configurations were based upon equipment rack counts and internal equipment rack layouts based upon the use of a cross-connect configuration that uses standard equipment racks and single-height conventional patch panels, as shown inFIG. 3A.
Theoretically, a network administrator should be able to introduce PoN service to a network by replacing a conventional patch panel (e.g., patch panel232) as shown in the configuration shown inFIG. 3A with a power hub (e.g., power hub233) to obtain the configuration shown inFIG. 3B. However, the increased vertical height requirements of the power hubs typically prevent implementation of such a simple approach. Due to the increased vertical rack space requirements of a power hub, insertion of PoN within a deployed cross-connect-based network infrastructure using power hubs can result in significant added expenses by requiring:
- 1. changes to internal rack configurations and cable configurations;
- 2. equipment racks to be added to equipment rooms;
- 3. expansion of equipment rooms to accommodate an increased number of equipment racks;
- 4. rearrangement of existing cabling and cable tray configurations to accommodate changes in equipment rack layouts.
The PPP supports insertion of PoN service without increasing, or otherwise adversely impacting, equipment rack space requirements as the PPP may have substantially the same dimensions as a conventional patch panel. Therefore, the PPP allows a new equipment room that uses PPPs for PoN insertion to be designed with a reduced number of equipment racks and reduced overall floor space requirements over a new equipment room design that uses power hubs for PoN insertion. Further, the PPP allows PoN service to be seamlessly inserted within any deployed network that uses conventional patch panels without affecting existing equipment rack or cable configurations, thereby greatly reducing the total cost of inserting PoN into an existing network, and allowing PoN service to be inserted within existing networks for which similar PoN insertion using power hubs would have been cost prohibitive.
FIG. 4A shows an exemplary PPP-based LAN cross-connect configuration that supports PoN service. As shown inFIG. 4A, usingLAN108 as an example, all ports of aswitch230 are connected to aconventional patch panel232 via cables connected from switch ports onswitch230 to punch-down blocks on the back side ofconventional patch panel232. End-user devices122-126 may be directly or indirectly connected to aPPP242 via horizontal cabling and punch-down blocks (not shown) on the rear face ofPPP242. Connections betweenpatch panel232 andPPP242 may be easily established and/or modified by changing patch cord connections between the front face ports ofpatch panel232 and the front face ports ofPPP242. Please note that the position ofpatch panel232 andPPP242 could be interchanged, without affecting the capabilities of the LAN cross-connect configuration shown inFIG. 4A. Further, additional patch panels may be inserted between either of the configurations described above and the building horizontal cabling.
FIG. 4B shows an exemplary PPP-based LAN interconnect configuration that supports PoN service. As shown inFIG. 4B, usingLAN108 as an example, end-user devices122-126 may be directly or indirectly connected to aPPP242 via horizontal cabling and punch-down blocks (not shown) on the rear face ofPPP242. Connections betweenswitch230 andPPP242 may be easily established and/or modified by changing patch cord connections between the front face ports ofswitch230 and the front face ports ofPPP242. In an interconnect configuration, as shown inFIG. 4B, technicians responsible for establishing and/or removing and/or changing connections between end-users (via the horizontal cabling plant) and the switch require access to switch230. Therefore, such a configuration is considered less secure than the equivalent cross-connect configurations shown inFIGS. 4A and 4B. Such an interconnect configuration is typically installed in networks in which securing configuration and security control overswitch230 is not required.
As demonstrated above, the PPP is capable of inserting PoN service into a new or existing LAN by simply being substituted for and replacing a conventional patch panel. As such, the PPP is capable of supporting both cross-connect configurations (as shown inFIG. 4A) and interconnect configurations (as shown inFIG. 4B).
Building horizontal cable plants typically terminate at one or more equipment room patch panels that serve as horizontal cabling demarcation points. Such demarcation patch panels provide a clean physical termination of the horizontal cable plant cables. In addition, a patch panel-based demarcation point allows the respective network cables within the horizontal cable plant to be easily tested forTIA category 5e and 6 compliance and certified as compliant prior to hand-off of responsibility for the horizontal cable plant from, for example, a cable installer to, for example, the network engineers responsible for connecting equipment to the horizontal cable plant. Under current industry practices, the rear punch-down blocks of a patch panel are considered to be a sufficiently reliable and stable termination point for a horizontal network cable. However, under current industry standards, RJ-45 jacks on the front face of a hub are not considered a sufficiently reliable and stable termination point for a horizontal network cable.
Accordingly, although the PPP is capable of supporting both cross-connect configurations and interconnect configurations, a power hub is only capable of supporting a cross-connect configuration. Further, use ofPPP242 in a cross-connect configuration (e.g., by replacingpatch panel232 orpatch panel234 inFIG. 3A) allows PoE service to be introduced to an existing cross-connect configuration without adversely impacting equipment rack and existing cable plant/facility layouts. Use ofPPP242 in a cross-connect configuration (e.g., by replacingpower hub233 inFIG. 3B) allows PoE service to be maintained and results in a rack space savings for each power hub replaced with a PPP. Use ofPPP242 in an interconnect configuration (as shown inFIG. 4B) to replace an existing or planned cross-connect configuration results in an overall space savings of nearly 50% over an equivalent cross-connect configuration. This savings may be significant to rack space management when upgrading non-powered networks to PoE networks. Additionally, the interconnect configuration eliminates the need for patch cords between a power hub and a conventional patch panel, thereby reducing the number of cables required, reducing cable congestion within LAN equipment rooms, and reducing the likelihood of cable-related network connection faults.
The power hub, on the other hand, as addressed above, cannot be substituted within an existing cross-connect configuration without adversely affecting existing facility equipment rack space requirements and in some cases may adversely affect equipment room equipment rack counts, facility layouts, and cable plant layouts. Further, for reasons addressed above, a power hub is not capable of supporting an interconnect configuration and, therefore, does not allow facilities to capitalize upon the space savings that can be achieved by using an interconnect configuration in those facilities for which an interconnect configuration is acceptable.
In summary, regardless of whether an existing equipment room is configured in a cross-connect or interconnect configuration, PoE may be inserted using a PPP-based approach without impacting equipment room space requirements. The PPP approach may avoid significant infrastructure planning and/or infrastructure upgrades that may be associated with a power hub-based approach.
An exemplary NMS is described in U.S. patent application Ser. No. 11/209,817, filed on Aug. 24, 2005 and entitled “SYSTEMS AND METHODS FOR NETWORK MANAGEMENT,” which is hereby incorporated by reference in its entirety including all references cited therein. An EMS may be an NMS that is tailored to provide at least a subset of NMS features, but may include all the features of an NMS. The EMS may be configured to meet the needs of a specific set of intelligent network devices.
The NMS/EMS such asNMS110 and EMSs112-114 (FIG. 1) may maintain a database of device information that may be retrieved from intelligent network devices (e.g., PPPs) throughnetwork system100. The NMS/EMS may further maintain within its database logical and physical topology information that describes the connectivity of devices withinnetwork system100. Physical topology information may include unique identifiers for each network device, physical locations of network devices such as building/floor/room number identifier, rack identification, position in the identified rack, horizontal cabling work area identification, and position relative to equipment racks, PPPs, PPP ports, PPP power sources, etc. Logical topology information may include network device connectivity such as PPP identification, PPP port number, jack identification, horizontal cable and work area jack identification, power source identification, etc. The database may also contain key cable performance measurements.
The PPP may serve as the primary repository of physical location information relative to the location of the PPP and the location of work areas supported by each of the ports within the PPP. For example, at the time of installation, a PPP may be configured with logical and physical location information (e.g., building, floor, room, GPS coordinates, IP address, IP mask, default IP gateway, etc.). The PPP may provide such information to the NMS/EMS, thus assuring that the logical and physical location information stored within the NMS/EMS is consistent with the actual network status. Further, at the time that each PPP port is wired via a punch-down block to an incoming cable, the location served by that cable may be entered into the PPP. For example, if the PPP is configured as a horizontal cabling demarcation patch panel, information such as the work area supported by the cable (e.g., building/floor/work area/wall jack, etc.) may be entered into the PPP and stored in a non-volatile memory. If the PPP is configured as a switch patch panel interface, information relating to the switch port supported by the cable (e.g., building/floor/equipment room/switched/port, etc.) may be entered and stored in the PPP. Such location information may be stored in a data structure specified by a definition interface file (DIF). In Simple Network Management Protocol (SNMP), a DIF corresponds to a Management Information Base (MIB). When the NMS/EMS requests information stored within a PPP's DIF data structure, the PPP may respond to the request by transmitting data stored within the data structure to the NMS/EMS, which may store the data within corresponding data structures in the NMS/EMS. For example, the NMS/EMS may have a DIF with data structures that include data structures that are identical to data structures defined by the PPP DIF so that information in a PPP's data structure may be retrieved and stored within a corresponding data structure within the NMS/EMS.
Further, the NMS/EMS may send PPP control parameters to control the PPP. The control parameters may be stored according to a DIF common to the PPP and the NMS/EMS so that efficient data transfer may be achieved. Each network device may have a unique DIF. Thus, the NMS/EMS stores all the unique DIFs within thenetwork system100 or within the subnet that it is configured to control and/or monitor.
FIGS. 5-8 show exemplary configurations of aPPP400.FIG. 5 shows an exemplary PPPfront panel402 that may include asystem status LED410, a plurality ofports404, a plurality ofport status LEDs406 where eachLED406 corresponds to oneport404, a plurality of port labels408, which may be TIA-606-A compliant, and tworack mounting brackets412 for mounting onto a rack, for example.
FIG. 6 shows a rear view of an exemplary PPPback panel420 that may include twopower input ports422 and424, a networkmanagement input port426, a networkmanagement output port428, twostatus LEDs430 and432 that correspond to the network management input andoutput ports426 and428, respectively, a plurality of punch-down blocks434 that are grouped into eight groups of three punch-down blocks434 per group, and a pair ofplates436 and438 that extend from side panels ofPPP400.Plates436 and438 protect punch-down blocks434 from physical damage. For example,plates436 and438 allowPPP400 to be rested rear face down on a flat surface without damaging punch-down blocks434.
As shown inFIG. 7, punch-down blocks434 provide wire connections toPPP400 for cables such as thehorizontal cabling216. Damage to punch-down blocks434 may render a PPP unusable. Thus,plates436 and438 reduce the risk of losingPPP400 due to damage to punch-down block434.
Each ofplates436 and438 may include a hole that may serve as agrounding point440. As shown inFIG. 8,PPP400 may be securely grounded to a rack by connecting aground strap442 between thegrounding point440 and a point on the rack.
FIG. 9 shows an example of threePPPs500a,500b, and500cand apower supply602 mounted onto arack600.Power supply602 may be a single power supply or may be a combination of multiple power supplies. For example, ifpower supply602 includes two power supplies, then each of the power supplies may be independently connected to each of the PPPs500a-500cin a redundant power supply configuration to provide fault tolerance.Power supply602 may include power output ports604a,604b, and604c, and, optionally, power output ports606a,606b, and606cif the redundant configuration is implemented. For example,power connections608a,608band608cmay connectpower output ports604a-604ctopower input ports422 of PPPs500a-500c, andpower connections610a,610b, and610cmay connectpower output ports606a-606ctopower input ports424 of PPPs500a-500cif the redundant power supply configuration is used.
FIG. 10 shows a diode “OR”circuit441 that may be included in each PPP500a-500cthat combines power from two power supplies in a redundant power supply configuration.Power supply602 may provide DC power having 48 volts, for example, and each of the power connections608a-608c(or942 ofFIG. 12) and 610a-610c(or944 ofFIG. 12) may include two wires, one positive and one negative. A 48 volt DC power based approach avoids including an internal 110 AC-to-DC power supply, thereby precluding the need for an internal fan in a PPP, so that a PPP may replace, in a one-for-one manner, an existing conventional patch panel. Each of thepower input ports422 and424 may include two connection points, one positive and one negative, so that the wires of the power connections608a-608cand610a-610cconnect to corresponding ones of the connection points of thepower input ports422 and424, positive to positive and negative to negative.
Diode circuit441 may include twodiodes442 and444 or equivalent circuitry that models the functions of these diodes. Cathode terminals of diodes442-444 may be electrically connected to negative connection points of respectivepower input ports422 and424 and anode terminals ofdiodes442 and444 may be electrically connected together at anode446. Positive connection points may be electrically connected to anode448.Nodes446 and448 provide power to the PPPs500a-500c.Diodes442 and444 prevent power from one of the power supplies from flowing into the other power supply.
Returning toFIG. 9,power supply602 may include anetwork port612 for connection toLAN108, for example, so that it may be controlled byNMS110,EMS112 and/orEMS114.Network port612 may be connected to an end of a daisy chain connecting all PPPs500a-500cofrack600, for example.FIG. 9 shows networkmanagement input port426 ofPPP500aconnected to a port ofswitch230 ofLAN108 and networkmanagement output port428 ofPPP500aconnected to networkmanagement input port426 ofPPP500b. Networkmanagement output port428 ofPPP500bmay be connected to networkmanagement input port426 ofPPP500c, and so on if there are other PPPs onrack600 until the last PPP of the daisy chain. Networkmanagement output port428 of the last PPP may be connected to networkport612 ofpower supply602. In this way, all the PPPs500a-500candpower supply602 ofrack600 may connect to theLAN108 using only one port ofswitch230, for example.
FIG. 11 shows a PPPinternal Ethernet switch450 that supports daisy chaining of network management input andoutput ports426 and428 and interface with internal PPP circuitry. The status of the network management input andoutput ports426 and428 may be indicated bystatus LEDs430 and432, respectively (as shown inFIG. 6). Table 1 below shows example indications of status LEDs and corresponding conditions associated with network management input andoutput ports426 and428.
| TABLE 1 |
|
| Network Status LED Indications |
| Network | | |
| LED | LED | | |
| Color | Status | Description | Notes |
|
| Off | Off | No connection to | If the system is otherwise |
| | the NMS/EMS. | operating normally and an |
| | | Ethernet cable is connected, |
| | | this could be an issue with the |
| | | panel's management interface. |
| Green | Flashing | The management | Normal operation. |
| | link on the PPP | |
| | is configured | |
| | correctly and | |
| | communication | |
| | messages | |
| | are currently being | |
| | processed. | |
| Green | Solid | The management | Normal operation. |
| | link on the PPP | |
| | is configured | |
| | correctly, but no | |
| | communication | |
| | messages are | |
| | currently being | |
| | processed (i.e., | |
| | the link is idle). | |
| Amber | Solid | The PPP is currently | If this persists for more than a |
| | trying to acquire | minute or two, the daisy chain |
| | DHCP address | of connections between |
| | information from | multiple PPPs may be incorrect |
| | the network. | or there are problems at the |
| | | DHCP server. |
|
FIG. 12 shows a block diagram of circuitry in anexemplary PPP900 that includesdiode circuit441, an in-linecurrent manager910, an analog-to-digital converter948, power-planes904 and908, acommon circuit902 and aport circuit906. Assuming that two power supplies are used to provide fault tolerance, analog-to-digital converter948 may monitor voltages of the two power supplies, nodes ofdiode circuit441, and output voltages generated by in-linecurrent manager910, and provide digital values of the monitored voltages toprocessor924 ofcommon circuit902 via optical coupler918 (also called optical isolator).Processor924 may also receive a value of current passing through in-linecurrent manager910. These voltage and current values may be processed byprocessor924 for processes such as:
- 1. determining an input power consumption for the PPP;
- 2. calculating threshold values for low current and high current conditions based upon past and current use;
- 3. generating an event notification toNMS110,EMS112 and/orEMS114 containing voltage, current and calculated power measurements;
- 4. generating an event notification toNMS110,EMS112 and/orEMS114 when voltage values monitored indiode circuit441 are below or above predetermined thresholds;
- 5. generating an event notification toNMS110,EMS112 and/orEMS114 when the current passing through in-linecurrent manager910 is below or above predetermined thresholds; and
- 6. generating event notification toNMS110,EMS112 and/orEMS114 when the power consumption of the PPP is below or above predetermined thresholds.
These and other event notifications may be logged byNMS110,EMS112 and/orEMS114 by storing data associated with the event notification, for example. An operator may view the logged event notifications on a per-port or per-PPP basis using a GUI for maintainingnetwork system100.
As shown inFIG. 12, in-linecurrent manager910 separately outputs current-managed power tocommon circuit902 andport circuit906 via separately fused (byfuses912 and914, respectively) power-planes904 and908. Signal lines between in-linecurrent manager910,common circuit902 andport circuit906 are isolated byoptical couplers918 and922 and/orcapacitive coupling919. In this manner, power failure in one of the power-planes904 and908 may be prevented from affecting power supplied to theother plane904 or908. Thus, operation of thecommon circuit902 may continue if power to power-plane908 ofport circuit906 fails, or operation ofport circuit906 may continue if power to power-plane904 ofcommon circuit902 fails.
For example, damage toport circuit906 due to an accidental connection of a high voltage source to a cable connected to a PPP port could be prevented from affecting operations ofcommon circuit902. Thus,common circuit902 may continue to communicate withNMS110,EMS112 and/orEMS114 such as reporting status despite failure ofport circuit906. Damage tocommon circuit902 would be similarly prevented from affecting operations ofport circuit906. Thus, PoE service may continue to be supplied to the PPP ports despite damage tocommon circuit902.
PPP embodiments may include any number ofport circuits906. Eachport circuit906 may receive power from anisolated power plane908 and eachport circuit906 may support a designated number of ports, as described herein. In this manner, anindividual port circuit906 may fail (e.g., due to a power surge or some other cause) and the remainingport circuits906 may continue to operate normally.
Processor924 may controlsystem status LED410 to indicate various PPP conditions as discussed above. Additionally, conditions such as listed below may be indicated by system status LED states:
- 1. DHCP addressing (dynamic address);
- 2. power supply noise out-of-limit;
- 3. firmware update;
- 4. firmware compatibility;
- 5. loss of power for a power-plane which may indicate conditions such as a blown fuse;
- 6. input power not received;
- 7. processor initializing;
- 8. port circuit working properly; and
- 9. port circuit failed but common circuit working properly.
LED states such as single or multiple colors and toggling between colors, sequencing LED colors or blink rates, coded pulsing, and/or intensity variations may be used for indications of particular PPP conditions. Additionally, a blinking rate may be used instead of setting the LED to an on state to save power. Table 2 below shows other examples of possible system status LED states for different conditions ofPPP900.
| TABLE 2 |
|
| PPP System Status LED Indications |
| LED | LED | | |
| Color | Status | Description | Status of Power Ports |
|
| Off | Off | No Power is being | Power is NOT being |
| | supplied to the PPP. | delivered to the ports |
| | | on the PPP. |
| Green | Flashing | System operating | Power is being delivered |
| | normally. | down the ports on the PPP, |
| | | as configured. |
| Amber | Solid | Out of voltage range | Power may or may not be |
| | condition. Less than 46 | delivered to any ports on |
| | VDC or more than 57 | the PPP. |
| | VDC is being supplied | |
| | to the PPP. | |
| Red | Solid | The main processor | Power may or may not |
| | on the PPP is NOT | be delivered to any ports |
| | operating properly and | on the PPP. |
| | power is NOT being | |
| | delivered to any | |
| | ports on the PPP. |
|
As shown inFIG. 12,port circuit906 may include acurrent manager934, aPoE manager936, anLED manager938, and a legacydetection support circuit940 for each port ofPPP900.Current manager934 may include control logic such as a state machine that may control and monitor current flowing via each port to a connected end-user device. For example,current manager934 may include current limiting circuitry that limits current flow based on values set in a register.
FIG. 13 shows an example ofcurrent manager934 that includes astate machine802, aregisters804, and a current limiter andswitch806.Processor924 may set control values inregisters804.State machine802 may control current limiter and switch806 based on the values inregisters804. For example,processor924 may define thresholds inregisters804. A first threshold may be an absolute current limit and a second threshold may set a current limit that may be exceeded for a first controlled period of time. When a port has exceeded the first threshold,state machine802 may immediately command the current limiter and switch806 to stop supplying current by opening a switch, for example. Additionally, thestate machine802 may update values in registers804 (change state) and generate an alarm signal (an event) toprocessor924 to indicate that the first threshold has been exceeded for the associated port.
When the second threshold is exceeded,state machine802 may change state by updatingregisters804 to set off a timer. If the current falls below the second threshold before the timer expires, thenstate machine802 may return to its earlier state; otherwise,state machine802 may enter a third state and switch off the port for a second control period of time before turning the port on again.State machine802 may also set values inregisters804 to record a number of times the second threshold has been exceeded, for example, so thatprocessor924 may retrieve the values inregisters804 for reporting toNMS110,EMS112, and/orEMS114.
Processor924 may monitor the current value measured by in-linecurrent manager910 over time (historical power use).Processor924 may periodically use these measurements to calculate new current thresholds for use in monitoring current flow toPPP900. Current thresholds based on the historical power use may be better indictors of abnormal current use.
PoE manager936 monitors each PPP port to detect the presence and characteristics of a PoE powered device (PD). As shown inFIG. 14,PoE manager936 may include control logic such as a state machine812, registers814, and a PD interrogator816. Any number of state machines812, registers814, and PD interrogators816 may be used, as may be dictated by implementation requirements, for example. If a PoE PD is detected, state machine812 may change state by updatingregisters814 and proceed to determine the PoE class of the PoE PD (classification). Once the class is determined,PoE manager936 provides power to the PD based upon the PD's PoE class such as defined in IEEE 802.3af, for example.PoE manager936 may also perform functions such as:
- 1. determining which Ethernet cable pairs to distribute PoE power over;
- 2. controlling the types of PoE equipment to be detected (i.e., IEEE 802.3af equipment only, legacy equipment and/or other variations);
- 3. activating or deactivating PoE service on a per-port basis;
- 4. setting PD PoE priority and/or maximum power level, on a per-port basis;
- 5. controlling PoE priority on a per-port basis by setting a control parameter that controls port power priority to one of critical, high and low. In a low power event, PDs with higher power priorities should be disconnected only after power has been disconnected to ports with a lower power priority;
- 6. controlling PoE detection techniques on a per-port basis; and
- 7. controlling PoE PD power classification on a per-port basis. PD power classification indicates an amount of power the PD may be expected to consume.
State machine812 may be controlled by control parameters stored byprocessor924 inregisters814. For example,processor924 may force a port to stop supplying power by setting a “stop bit” in registers814. The “stop bit” may change the state ofstate machine814 which may respond by opening a switch disconnecting power to the PD, for example. State machine812 may report port status changes toprocessor924 by sending one or more alert messages (events) toprocessor924 or by updatingregisters814 with new status information.Processor924 may obtain the status information by reading the contents ofregisters814.
Status updates provided byPoE Manager936 toprocessor924 may indicate conditions such as:
- 1. no PD is attached to the PPP port;
- 2. no power is being delivered over a PPP port;
- 3. power is being delivered over a PPP port; and
- 4. a PD has been detected but its power requirements cannot be determined.
Processor924 may relay such status updates fromPoE manager936 via an event notification toNMS110,EMS112, and/orEMS114. In this manner,NMS110,EMS112, and/orEMS114 may maintain accurate port-level connection and PoE-related information.
LED manager938 controlsport LEDs406 and may include control logic such as astate machine822, aregisters824, and anLED drive circuit826, as shown inFIG. 15.State machine822 controlsLED drive circuit826 based on values inregisters824 which may be set byprocessor924. For example,processor924 may forceLED406 of a specific port to blink at a specified rate by setting values inregisters824 in response to move/add/change requests received fromNMS110,EMS112, and/orEMS114. Other LED states such as single or multiple colors, toggling between colors, sequencing LED colors or blink rates, coded pulsing, and/or intensity variations may be used for indications of particular port conditions.State machine822 may controlLED drive circuit826 based on the values inregisters824 set byprocessor924.
State machine822 may change values inregisters824 based on current LED functions being performed reflecting the status of the associated port so thatprocessor924 may read the status when performing monitoring functions. Port conditions such as the following may be indicated using LEDs406:
- 1. power level indicator for power classification of connected PD;
- 2. power removed from the port (lockdown), over-current for all ports per classification;
- 3. over-current conditions for a particular port (administrative restriction);
- 4. backing off supplying power because connected device is a powered switch;
- 5. PD voltage incompatibility;
- 6. port power interface failure;
- 7. power classification fault; and
- 8. port power noise outside of limits.
Additionally,LEDs406 may be used to assist an operator for patch cord tracing and/or direct patch cord removal/change.
Other LED functions may be similarly set byprocessor924, such as color, for example. Additionally,state machine822 may control theLED406 viaLED drive circuit826 to perform a specific function based on conditions of the associated port. Examples of this type of control are shown in Table 3, below.
| TABLE 3 |
|
| Port Status LED Indications |
| Port | | |
| LED | LED | | |
| Color | Status | Description | Status of Power Ports |
|
| Off | Off | No Powered Device (PD) | Power is NOT being |
| | is wired to this particular | delivered down this |
| | port on the PPP. | port on the PPP. |
| Amber | Solid | The PPP is determining | Power is NOT being |
| | the PD′s power requirements. | delivered down this |
| | This occurs for 5 seconds | port on the PPP. |
| | after the PD is connected. | |
| Green | Solid | Port operating normally. | Power is being |
| | | delivered down this |
| | | port on the PPP. |
| Red | Solid | The system has failed | Power is NOT being |
| | to determine the PD | delivered down this |
| | power requirements | port on the PPP. |
| | for this port. Perhaps this | |
| | PD is not an 802.3 af | |
| | compliant or legacy | |
| | device (e.g., Cisco). | |
| | It could also be a port | |
| | configured for 802.3 | |
| | af and an alternate PoE | |
| | device has been connected. |
|
Legacydetection support circuit940 together withPoE manager936 andprocessor924 executes anexemplary process1500 shown inFIG. 16 that determines whether an end-user PD connected to a port is a first type of PoE device such as an IEEE 802.3af compatible device or a second type of PoE device such as a legacy device.
Instep1502, the process determines whether a port is connected to a first type PD. For example, if a first type PD is an IEEE 802.3af PoE device, then it may be detected by procedures specified in the IEEE 802.3af standards. If a first type PD is detected, then the process goes to step1504; otherwise, the detection process, atstep1502, may be repeated after a predetermined delay. Instep1504, the process may classify the PoE PD (determining power requirements by interrogating the PoE device) and the process goes to step1510. Instep1510, the process may provide power to the PoE PD according to the determined classification, may set the LED associated with the port to a state as specified by contents ofregisters824, and may optionally update a state field inregisters824. Next, the process goes to step1512.
Instep1512, the process determines whether there is a change in the status of the port, e.g., whether the connected PD has been disconnected. If there is a change, the process returns to step1502; otherwise, the process goes to step1514. Instep1514, the process determines whether the PPP is turned off. If the PPP is turned off, the process goes to step1516 and ends; otherwise the process returns to step1512.
Whileprocess1500 is executing, anotherprocess1550, as shown inFIG. 17, may be executing based on a timer to determine whether a first type device is connected. If a first type of device is not connected, the process executes a second type detection process. Instep1552, the process determines whether the timer has expired. If expired, the process goes to step1554; otherwise, the process returns to step1552. Instep1554, the process determines whether the port is supplying power to a first type or a second type PoE PD. If the port is supplying power, the process goes to step1556; otherwise the process goes to step1558. Instep1556, the timer is set and the process returns to step1552.
Instep1558, the process determines whether the port is connected to a second type device such as a legacy device (legacy relative to IEEE 802.3af PoE PDs). An example of how such a determination may be made is shown inFIG. 18A, which shows an exemplary PPP legacydetection support circuit940 connected via a 4-pair twisted-pair cable to an exemplary legacy PD configured to receive PoN power over wire-pairs 4/5 and 7/8. Legacydetection support circuit940 may include an oscillating signal generator1202 that transmits an oscillating signal on wire-pair wires4,5 via transmission driver1204 and transformer1206.
A legacy PD may be configured such that when a cable is inserted into the PD, physical switch1210 is moved from an open to a closed position. Therefore, if the PD is a legacy device, the oscillating signal emitted by oscillating signal generator1202 on wire-pair wires4,5 will be transmitted via transformer1208 and1212 to wire-pair 7/8, and detected by detection circuit1218, via receiver1216 and transformer1214. If the PD is not a legacy device, physical switch1210 remains in the open position and detection circuit1218 does not receive a corresponding signal in response to the oscillating signal output. If no signal is received detection circuit1218 determines that the PD is not a legacy device.
If detection circuit1218 determines that the connected PD is a legacy device, detection circuit1218 communicates (via connection lines not shown inFIG. 18A) with polarity reverse switch1220 to place a negative voltage across leads1222 and1224, as shown inFIG. 18B. If detection circuit1218 determines that the connected PD is not a legacy device, detection circuit1218 communicates with polarity reverse switch1220 to place a positive voltage across leads1222 and1224. In this manner, an appropriate voltage is placed upon leads1222 and1224 and power is transmitted via wiretaps in transformers1206 and1214 and via wire-pairs 4/5 and 7/8, respectively, to wire taps on transformers1208 and1212 in the PD device. Power received by the PD device at wire taps on transformers1208 and1212 is delivered via PD circuit1226 with diode circuit1228 to drive PD load1230.
Returning toFIG. 17, if a second type PoE PD is detected, the process goes to step1560; otherwise, the process goes to step1556. Instep1560, the process determines the power requirements of the second type device, provides the required power, and goes to step1562. Instep1562, the process determines whether the PPP has been turned off. If turned off, the process goes to step1564 and ends; otherwise, the process goes to step1556.
The managers within port circuit906 (i.e.,current manager934,PoE manager936, and LED manager938) may operate as independent state machines that interact withprocessor924 to receive control parameter updates fromprocessor924 and to provide status updates toprocessor924. As noted above, theport circuit906 may operate independently ofprocessor924. For example, in the event that the PPP is powered down, reset or in self-test, either intentionally (e.g., to field-update newly downloaded processor code) or unintentionally (due to a power failure or internal fault-generated reset) port circuit processing may be unaffected andport circuit906 may continue to support PoE-based services to the PPP ports based on the latest parameters received fromprocessor924. Onceprocessor924 is again operational, normal communications betweenprocessor924 and theport circuit906 may resume.
Returning toFIG. 12,common circuit902 may includeprocessor924, amemory926 which may include random access memory (RAM)928 andnon-volatile memory930, and a two-port Ethernet switch932. If PPP control parameters and configuration data such as location and connection information and associated DIFs are stored innon-volatile memory930,PPP900 may return to the stored PPP configuration if power was accidentally lost causingPPP900 to restart, for example. Control and configuration parameters that may be stored innon-volatile memory930 may include:
- 1. PPP configuration parameters;
- 2. PPP and PoE-related current and voltage thresholds;
- 3. PPP network IP configuration data;
- 4. event notification (e.g., SNMP trap) recipients; and
- 5. PPP identity, PPP physical location information and associated power supply identification and location information.
Processor924 may control operations ofPPP900 based on control parameters and data stored inmemory926, and may communicate with other devices viaEthernet switch932.Memory926 may be used to store software that may be executed byprocessor924.Processor924 may controlport circuit906 to perform its functions by setting theregisters804,814, and824 based on received control parameters. Additionally,processor924 may perform the following functions:
- 1. controlling a port based on whether the PoE PD may receive AC/DC PoE detection or DC only detection;
- 2. controlling whether control/administration of port-level values by an NMS/EMS may be accepted by the PPP; and
- 3. controlling whether wire assignments for transmitting power may be changed.
NMS110,EMS112, andEMS114 may interface with a GUI that permits an operator to maintain and control the network and administer desired policies. For example, such a GUI may permit the operator to graphically view monitored power and one or more failure statuses of devices such as PPPs and devices connected to the PPPs.
The GUI may provide a graphical display of the topology ofnetwork system100 which may be organized into trees, and each branch of the tree may form a sub-network (subnet) ofnetwork system100. The GUI may display a subnet in relation to actual physical locations such as, for example, a floor plan detailing physical aspects of the building where PPPs may be disposed, such asequipment closet206 and racks600. The GUI may provide displays such as:
- 1. a hierarchical view of all PPPs;
- 2. a listing of PPPs;
- 3. information for each PPP of a selected rack including logged event notifications; and
- 4. detailed configuration, control and status information for a specifically selected PPP, including:
- a. a message log of event notifications generated by the PPP;
- b. current and historical power usage values for each PPP; and
- c. physical location and logical connection information.
The GUI may provide capabilities to support functions such as searching for panels of a selected subnet across a range of IP addresses, viewing and/or changing information on a per-port basis of each PPP, etc.
The network topology may be derived from PPPs by either explicitly requesting needed information or receiving unsolicited notifications from PPPs resulting from local monitoring functions. For example, data that may be received from PPPs may include:
- 1. physical location information such as room identification, rack identification, horizontal cabling work room identification;
- 2. connection information such as PPP and port identification, switch port identification, power supply source identification;
- 3. whether or not powered devices are connected to a port;
- 4. an amount of current consumption. This is especially relevant to intelligent network devices such as a PPP because PPPs supply power to their ports and the total amount of power supplied through a PPP may be monitored for network power budget purposes;
- 5. information (e.g., a PD identifier and/or a PPP port identifier) related to an abnormal termination of power to a powered PD and which, based upon the PPP's PD interrogation techniques, appears to have been disconnected;
- 6. non-compliant PDs such as PDs whose power consumption is over specified limits;
- 7. PPP power consumption has dropped below a threshold;
- 8. PPP power consumption has exceeded a threshold;
- 9. PPP physical location has been changed;
- 10. PPP incoming voltage is outside desired range (e.g., too high or too low);
- 11. PPP power fuse has blown;
- 12. the amount of incoming power to a PPP;
- 13. PPP-detected management port connections; and
- 14. PPP-detected management port disconnections.
An operator may use the GUI to controlnetwork system100 by setting various parameters of PPPs. For example, an operator may:
- 1. perform maintenance by monitoring any PPPs (e.g., verify port connections by sending test signals, confirm connection to a PPP, etc.);
- 2. designate priority for output power for any port of a PPP. For example, a port may be designated as low, high or critical priority;
- 3. set thresholds for power consumption for a PPP or any of its ports. For example, such thresholds may be set in the form of current and/or voltage values;
- 4. perform real-time monitoring and setting thresholds of current and voltage of power inputs for a PPP, for example. Thresholds may be set for detection of alarm conditions;
- 5. monitor a parameter, such as a voltage or current, of a first power supply, a parameter of a second power supply and a parameter at a summation point when a PPP is supplied by two power supplies, for example;
- 6. command outputting full power for all ports of a PPP;
- 7. detect and display power consumption for a PPP or one or more ports of the PPP;
- 8. assign dynamic (DHCP) or static IP address to a PPP at installation, for example;
- 9. selectively deactivate/re-activate power service to a PPP port;
- 10. control operation of LEDs of a PPP (e.g., blinking rate, on/off, etc.); and
- 11. assign power mode (e.g., normal, forced or forced with device check) for each port of a PPP. For example, in ‘normal’ power mode, the PPP may manage the application of PoE power to a port based upon whether a device is connected to a port and/or the type of device connected to the port and/or power consumption monitoring; in ‘forced with device check’ power mode, the PPP may apply PoE power to a port when a device is connected to the port, regardless of the type of device connected and/or without power consumption monitoring; and in ‘forced’ power mode, the PPP may apply PoE power to a port without checking for a device or any power consumption monitoring.
It will be appreciated that various of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. For example, “a” may denote the use of one or more elements. The lists presented herein are intended to be exemplary rather than limiting. Also, variations presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art, and are also intended to be encompassed by the following claims.