JP5101534B2 - Personal network system composed of portable computer and IP phone - Google Patents

Description

  The present invention relates to a personal network system composed of a portable computer and an IP telephone.

  In office buildings and public facilities, a local area network (LAN) that employs a communication method called Ethernet (registered trademark) is laid, and a computer connected to the LAN is placed on each user's desk. Has been. As a computer used by a user, a notebook personal computer (hereinafter referred to as a notebook PC) has become mainstream instead of a conventional desktop personal computer. In addition, with the widespread use of LANs and wide area networks, many IP telephones with low usage charges have been introduced. An IP telephone transmits a packet to a LAN using a communication technology called VoIP (Voice over Internet Protocol) to enable telephone communication over TCP / IP. In this way, in recent office environments, notebook PCs and IP telephones are placed on the desks of each user, and therefore the number of communication cables and power cables that are wired to that point tends to increase.

By the way, in Ethernet (registered trademark), a technology called Power over Ethernet (POE) that supplies data and power through a communication cable was standardized as IEEE 802.3af in 2003 and applied to various network devices. Has been. In POE, power is transmitted from a power supply device ( PSE : Power Sourcing Equipment) to a power receiving device (PD: Powered Device) simultaneously with data through a single communication cable called UTP (Unshielded Twist Pair) cable. Direct power supply from the DC adapter can be omitted.

  IP telephones that can support POE and have a switching hub function have also been used. When an IP telephone with a built-in switching hub corresponding to POE is connected to the LAN as a PD, a notebook PC can be connected to the port of the IP telephone and connected to the LAN. In this case, a single UTP cable is wired from the LAN switching hub to the IP phone to transmit data and power, and the power cable of the AC / DC adapter is connected only to the notebook PC. Can be used by connecting to a LAN. Since the LAN is usually provided with an uninterruptible power supply called UPS (Uninterruptible Power Supply), it is not necessary to take measures against power outages for IP telephones.

Patent Document 1 discloses a technique for connecting another information processing apparatus via a network expansion apparatus connected to a PC with a USB cable. The network expansion device is provided with a POE circuit unit, and data lines and power lines are connected to the Ethernet expansion port to enable power supply and data communication to other information processing apparatuses. Patent Document 2 discloses a VoIP telephone corresponding to POE. This document discloses a technique for providing a power supply function to a LAN device such as a switching hub or a router and supplying power to the VoIP telephone terminal through these devices. The document further describes that a battery is built in the power supply / reception device, and power is supplied from the battery to the POE power reception unit when power supply from the power supply device or the power adapter is interrupted. Patent Document 3 discloses a circuit and a method for performing data transmission of a midspan PSE configuration in a POE system.

JP 2006-163786 A JP 2006-203730 A JP 2008-521342 A

  In the current Ethernet (registered trademark), the standards of 100BASE-TX having a transmission rate of 100 Mbps and 1000BASE-T having a 1 Gbit bps are mainly used. IEEE 802.3af defines two options, A (alternative A) and B (alternative B), as power supply methods using POE. The option A method is a method in which the voltage for power is superimposed on the two pairs of core wires used for data transmission among the four pairs (8 wires) of the UTP cable, and the option B method is four pairs of core wires. In this method, two pairs of empty core wires that are not used for data transmission are used for power. In 100BASE-TX, data transmission is performed by a ternary encoding method, but power can be supplied by either the option A method or the option B method based on the POE.

  On the other hand, in 1000BASE-T, four pairs of core wires of a UTP cable are simultaneously used for transmission and reception, and data transmission is performed by a quinary coding method. The quinary coding method has a difficult aspect for noise countermeasures because the margin between the voltage of the data signal and the threshold is small. If the POE is introduced into 1000BASE-T, the option A method is inevitably adopted. However, since the option A method has noise from the power source superimposed on the data signal, at present, the 1000BASE-T is used. It is difficult to supply power to the PD by the POE using a UTP cable for data transmission. Many of the POE compatible IP telephones with a built-in switching hub are connected to the network by 100BASE-TX and are supplied with power by the option B method.

  However, notebook PCs have recently been equipped with network adapters that support 1000BASE-T. Even if such a notebook PC is connected to a switching hub built in an IP telephone compatible with 100BASE-TX, the IP telephone can be connected to a LAN only at a transmission speed of 100 Mbps. Even a PC can transmit data only at 100 Mbps. In order to solve this problem, switching is provided with a 1000BASE-T interface to a LAN, a 100BASE-TX interface to an IP telephone that is a POE compatible device, and a 1000BASE-T interface to a notebook PC that is a non-POE compatible device.・ A hub may be installed on the desk.

  In this case, there are problems such as a space for installing the switching hub, power supply to the switching hub, and an increase in cost. Furthermore, power outage countermeasures for IP telephones and switching hubs are also required. By the way, notebook PCs are used by being attached to a function expansion device such as a docking station or a port replicator in order to simplify the functions prior to weight reduction when carried and to realize functions comparable to desktop computers in the office. Sometimes. It is conceivable to solve the above-mentioned problems by using this function expansion device.

  Accordingly, an object of the present invention is to simplify data wiring and power wiring of a personal network system including an IP telephone and a portable computer. A further object of the present invention is to provide a personal network system that can save the space around the desk. A further object of the present invention is to provide a personal network system that does not reduce the transmission speed of a portable computer. It is a further object of the present invention to provide a personal network system that allows an IP telephone to be used even during a power failure while suppressing an increase in cost. A further object of the present invention is to provide a personal network system that can reduce power loss that occurs in a communication cable connected to an IP telephone. A further object of the present invention is to provide a portable computer function expansion apparatus and data communication method for use in such a personal network system.

  The present invention relates to a personal network system connectable to a LAN. A user using a portable computer may use a function expansion device to use a function comparable to a desktop in a fixed use place such as an office desk or a factory work place. In addition, IP telephones may also be arranged at such places of use. The personal network system in the present invention means a configuration of network devices and a connection form thereof in a fixed use place where a portable computer used by a user, its function expansion device, and an IP telephone are arranged.

When the portable computer, the IP phone, and the function expansion device are arranged alone, a communication cable and a power cable for connecting to the LAN are required, respectively, but it is desirable that the number of these wirings be as small as possible. If the IP telephone corresponding to the POE, can be omitted power cable for IP phones by providing a PSE to LAN, the power loss in the communication cable so normally be substantial distance from the PSE to the place of use It cannot be ignored. In addition, it is desirable that a personal network system can be constructed without providing extra devices other than the IP telephone, portable computer, and function expansion device at the place of use. Furthermore, it is desirable that the portable computer can be connected to the LAN without being affected by the communication speed of the IP telephone.

  In the present invention, the IP telephone corresponds to a POE power receiving device, and the function expansion device is provided with a switching hub and a power supply device corresponding to the POE. The switching hub can transmit / receive data to / from the LAN at the transmission rate of the first standard. The power supply apparatus supplies power to the IP telephone based on POE. The transmission rate of the IP telephone is a second standard that is slower than the first standard. Even in this case, since the switching hub can perform data communication with the LAN at the transmission rate of the first standard, the portable computer connected to the switching hub can communicate with the LAN at a transmission rate of the second standard. Data can be transmitted at a high transmission rate of the third standard. However, the transmission rate of the third standard is not more than the first standard.

  Since the POE is not used between the LAN and the switching hub, the first standard can be a standard with a high transmission speed, and even if the wiring is long, power is not supplied based on the POE, so the communication cable is used. There is no power loss. Since the switching hub is housed in the function expansion device, it is not necessary to secure a new space in the place of use. The power supply apparatus can receive power from an AC / DC adapter connected to the function expansion apparatus and supply power to the IP telephone. Therefore, since it is not necessary to supply power from the AC / DC adapter to the power supply apparatus and the IP telephone, it is not necessary to provide an outlet for the AC / DC adapter at the place of use.

  If the power supply device is supplied with power from a battery mounted on the portable computer in the event of a power failure, there is no need to take extra measures against the power failure. Further, it is desirable to supply power from the power supply device to the switching hub. If the Ethernet controller of the portable computer complies with the first standard, it can be connected to the LAN at a transmission speed corresponding to the first standard. Further, if the switching hub is configured to operate in layer 2 of the OSI reference model, for example, the first standard and the third standard are set to 1000BASE-T, and the second standard is set to 100BASE-TX. Can do.

  According to the present invention, data wiring and power wiring of a personal network system including an IP telephone and a portable computer can be simplified. Further, according to the present invention, a personal network system capable of saving the space around the desk can be provided. Furthermore, according to the present invention, a personal network system that does not decrease the transmission speed of the portable computer can be provided. Furthermore, according to the present invention, it is possible to provide a personal network system that can use an IP telephone during a power failure while suppressing an increase in cost. Furthermore, according to the present invention, it is possible to provide a personal network system capable of reducing power loss that occurs in a communication cable connected to an IP telephone. Further, according to the present invention, it is possible to provide a function expansion device and a data communication method for a portable computer used in such a personal network system.

It is a figure which shows schematic structure of the network system concerning embodiment of this invention. It is a perspective view which shows the external appearance of a notebook PC and a function expansion device. It is a block diagram which shows the state which connected notebook PC to the function expansion apparatus. It is a wiring diagram explaining a method for supplying power to an IP phone based on POE by a power feeding device. It is a flowchart which shows operation | movement of a network system.

  FIG. 1 is a diagram showing a schematic configuration of a network system 1 according to an embodiment of the present invention. The LAN 10 enables mutual communication through a wired medium or a wireless medium between a plurality of use places in a limited range such as a company or a public facility. The LAN 10 is also connected to the Internet network 11 through the gateway server 15 and connected to the public telephone line 13 through the IP gateway server 17. The LAN 10 conforms to the Ethernet (registered trademark) standard, which is one of the LAN standards established by the IEEE 802 committee under the IEEE.

  Ethernet (registered trademark) is defined by a physical layer and a data link layer of an OSI reference model having seven layers. The LAN 10 may also include a high-speed wireless network based on a wireless LAN (IEEE 802.11) standard established by the IEEE 802 committee. The LAN 10 includes a wireless base station (also referred to as an access point) 23, switching hubs 25 and 27, a gateway server 15, an IP gateway server 17, a DHCP server 19, and RJ (Registered Jack) 45 connectors 29a to 29f. It consists of These components are connected to each other in a star topology.

  The LAN 10 constitutes not only a computer data communication network but also a VoIP IP network. The IP network realized in the LAN 10 is an H.264 standardized by ITU-T, which is one of the organizations of ITU (International Telecomunication Union). A well-known protocol such as SIP standardized by H.323 or IETF (Internet Engineering Task Force) can be adopted. The IP gateway 17 constitutes an Internet Protocol Private Branch Exchange (IP-PBX) in the LAN 10.

  The IP gateway 17 interconverts both the call control or signaling protocol and the voice and image data protocol between the public telephone line 13 and the LAN 10. After establishing communication between the telephones by call control, the IP gateway 17 assembles a packet from the voice signal received from the public telephone line 13 and sends it to the IP telephone 33 connected to the LAN 10. The IP gateway 17 receives the packet received from the IP telephone 33. The voice signal is converted and sent to the public telephone line 13.

  The IP gateway 17 is provided with an address table for mutual conversion between IP addresses and telephone numbers, and performs call control between the public telephone line 13 and the IP telephone 33, or an IP telephone connected to the LAN 10. Call control and session establishment for extension calls between them. The IP gateway 17 also performs authentication and registration of the IP telephone, and realizes additional functions such as transfer and hold. The function of the IP gateway 17 may be distributed to a plurality of servers. The gateway server 15 relays data transfer between the LAN 10 and the Internet 11.

  Each of the ROMs of the switching hubs 25 and 27 stores a MAC address. The MAC address is a unique physical address given to a network device such as a LAN card, and is composed of 48 bits in Ethernet. The switching hubs 25 and 27 each have 256 ports for connecting the IP telephone 33 and the notebook PC 35 to the LAN 10. The number of switching hubs and the number of ports can be arbitrarily selected according to the scale of the network. The switching hubs 25 and 27 perform baseband transfer conforming to the standard of 1000BASE-T, and apply a bridge function for transferring MAC frames at Layer 2 (data link layer) of the OSI reference model to 256 ports. Data can be transmitted at 1 Gbps. The switching hubs 25 and 27 may also be referred to as LAN switches or layer 2 switches.

  In FIG. 1, the output ports of the switching hubs 25 and 27 are connected to the RJ45 connectors 29a to 29f by category 5 or higher UTP cables. The RJ45 connectors 29 a to 29 f are installed in the vicinity of a desk 39 that constitutes the personal network system 30. On the user's desk 39, the notebook PC 35, the function expansion device 100 of the notebook PC 35, and the IP telephone 33 constituting the personal network system 30 are arranged. The desk 39 has significance as a close or limited range where the user uses the notebook PC 35 and the IP telephone 33. The function expansion device 100 is typically connected to the RJ45 connector 29b with a UTP cable 32 of category 5 or higher. Other function expansion devices can be similarly connected to the other RJ45 connectors.

  Since it is necessary to route UTP cables from the switching hubs 25 and 27 to many places of use, the switching hubs 25 and 27 are scattered and installed at main places in the building. Therefore, since the distance between the output port of the switching hub 25 and the RJ45 connector 29b is relatively long, if power is supplied by POE through the UTP cable 31, power loss becomes a problem, but the network system 1 The function expansion device 100 is not supplied with power using POE. The function expansion device 100 is called a docking station or a port replicator, and includes an optical drive, a hard disk drive, a USB port LAN port, or a display terminal. The user can use a function comparable to that of a desktop PC simply by attaching the notebook PC 35 to the function expansion device 100.

  The IP telephone 33 has an Ethernet (registered trademark) interface, and is connected to the function expansion device 100 via a category 5 or higher UTP cable 41. The IP telephone 31 is similar to a general business phone in the shape of the handset and the arrangement of numeric buttons, and has various telephone functions such as speed dial, hold, and transfer. The wireless base station 23 is wired to the LAN 10, and can be connected to the LAN 10 through the wireless base station 23 when the notebook PC 35 includes a wireless interface. The UPS 21 supplies power for operating the LAN 10 for a predetermined time during a power failure.

  FIG. 2 is a perspective view showing the external appearance of the notebook PC 35 and the function expansion device (docking station) 100. The notebook PC 35 includes a system housing 45 having a keyboard and a pointing device mounted on the surface thereof and housing many devices therein, and a display housing 47 having a liquid crystal display (LCD) mounted on the surface thereof. The notebook PC 35 can use the device mounted on the function expansion device 100 as a part of the notebook PC 35 by connecting the connector 49 provided at the bottom of the system housing 45 to the connector 101 of the function expansion device 100. it can. The notebook PC 35 is mounted with a battery, and operates with power supplied from the battery when carried.

  Further, an AC / DC adapter (not shown) can be connected to the notebook PC 35, and the user can use the notebook PC 35 while charging a battery with a commercial power source. In the function expansion device 100, an AC / DC adapter 103 including a plug 104 connected to an outlet of a commercial power supply is connected to the power connector 105, and power is supplied from the commercial power supply to the device mounted on the function expansion device 100. At the same time, when the notebook PC 35 is attached, power can also be supplied to the notebook PC. When the notebook PC 35 is attached to the function expansion device 100, the power connector of the notebook PC 33 is hidden behind the function expansion device 100 so that an AC / DC adapter cannot be directly connected to the notebook PC 33.

  FIG. 3 is a block diagram showing a state where the notebook PC 35 is connected to the function expansion device 100. The AC / DC adapter 53 is connected to the power connector 54 when a commercial power source is used without the notebook PC 35 attached to the function expansion device 100. The AC / DC adapter 53 outputs a DC voltage of 20 V to the secondary side when an AC voltage is supplied to the primary side. The power connector 53 is connected to the charger 57, the DC / DC converter 61, and the pin terminal 71a through the diode 55. The pin terminals 71a to 71d correspond to a connection portion between the connector 49 of the notebook PC 35 and the connector 101 of the function expansion device 100 in FIG.

  A battery pack 67 is connected to the charger 57. The battery pack 67 conforms to the standard of the smart battery system, and a lithium ion battery, a protection circuit, a control IC chip, and the like are housed inside the case. The charger 57 receives power from the AC / DC adapter 53 or the AC / DC adapter 103 and charges the battery pack 67.

  The AC / DC adapter 53 cannot be physically connected to the connector 54 when the notebook PC 35 is attached to the function expansion device 100. The battery pack 67 is connected to the DC / DC converter 61 and the pin terminal 71 c through the diode 63. The DC / DC converter 61 converts the voltage supplied from the AC / DC adapter 53, the AC / DC adapter 103 or the battery pack 67 into a predetermined voltage and supplies it to the system load 59 of the notebook PC 35.

  The system load 59 includes a CPU, a main memory, a display, a hard disk drive, a chip set such as an ICH or an MCH, etc. that configure the functions of the notebook PC. A PCI bus constituting a part of the system load 59 is connected to the pin terminal 71b. The Ethernet controller 65 is a part of the system load 59, but is described separately for convenience of explanation. The Ethernet controller 65 operates by receiving power from the DC / DC converter 61. The Ethernet controller 65 is hardware that shares the data link layer and the physical layer of the OSI reference model, and is connected to the RJ45 connector 69 attached to the notebook PC 35, the PCI Express Bus of the system load 59, and the pin terminal 71d.

  The RJ45 connector 69 is used to connect the notebook PC 35 to the LAN 10 without going through the function expansion device 100. The AC / DC adapter 103 is connected to the power connector 105 when the notebook PC 35 is used in a state where it is mounted on the function expansion device 100. The AC / DC adapter 103 outputs a DC voltage of 20 V to the secondary side when an AC voltage is supplied to the primary side. The AC / DC adapter 103 is connected to the power failure detection circuit 121, the FET 119, the DC / DC converter 109, and the pin terminal 71a through the power connector 105 and the diode 107. The DC / DC converter 109 converts the voltage supplied from the AC / DC adapter 103 into a predetermined voltage and supplies it to the system load 111 of the function expansion device 100.

  The system load 111 includes a hard disk drive, an optical drive, a USB controller, and the like, and is connected to the pin terminal 71b via a PCI bus. The power failure detection circuit 121 includes a comparator, and is connected to the cathode of the diode 107 and the gate of the FET 119. The power failure detection circuit 121 determines that the power failure or the connection of the AC / DC adapter 103 has been disconnected when the output voltage of the AC / DC adapter 103 drops to, for example, 15 V, and controls the FET 119 to be turned off. The DC / DC converter 113 is a step-up switching regulator that supplies a voltage of 48 V to the power feeding device 115. The switching hub 117 has an interface for performing baseband transfer conforming to the 1000BASE-T standard on the primary side, and performs baseband transfer conforming to the 1000BASE-T standard and the 100BASE-TX standard on the secondary side. It has two interfaces to perform, and transfers MAC frames at layer 2 (data link layer) of the OSI reference model.

  The switching hub 117 is a PHY (Physical Layer) chip that bi-directionally converts a logical signal processed internally and an electrical signal transmitted via a UTP cable, encodes and combines MAC frames, and relays between ports. A switch chip, a frame buffer for temporarily storing MAC frames, an address table, and the like.

  The switching hub 117 has an auto-negotiation function and a flow control function, and automatically determines the transmission speed between the IP telephone 33 and the notebook PC 35, or transfers the MAC from the primary side of the high-speed transmission to the secondary side of the low-speed transmission. The frame buffer can be controlled so as not to overflow even when a frame is flowed. The switching hub 117 has a primary side interface (port) connected to the RJ45 connector 123, a secondary side interface (port) conforming to the 1000BASE-T standard is connected to the pin terminal 71d, and conforms to the 100BASE-TX standard. A suitable interface (port) is connected to the RJ45 connector 125. The RJ45 connector 123 is connected to the RJ45 connector 29b shown in FIG. 1, and the RJ45 connector 125 is connected to an IP telephone 33 as a POE power receiving device.

  The power feeding device 115 supports POE and supplies power to the IP telephone 33 through the UTP cable 41. The power feeding device 115 is connected to the RJ45 connector 125, and protocol functions defined by the POE such as detection of POE compatible devices or non-POE compatible devices, classification of charging side devices, and supply and stop of power to the power receiving device by the option B method. It has. The power feeding device 115 is also connected to the switching hub 117 and supplies power to the switching hub 117. Since the switching hub 117 is a POE non-compliant device, it is not necessary to supply power based on the POE protocol.

  FIG. 1 and FIG. 3 merely show a simplified configuration and connection relationship of main hardware related to the present embodiment in order to describe the present embodiment. In addition to those mentioned in the description so far, many devices are used to configure the notebook PC 35 and the function expansion device 100. However, they are well known to those skilled in the art and will not be described in detail here. A person skilled in the art also arbitrarily selects a plurality of blocks described in the figure as one integrated circuit or device, or conversely, a block is divided into a plurality of integrated circuits or devices. Is included in the scope of the present invention. In addition, the types of buses and interfaces connecting the devices are merely examples, and other connections are included in the scope of the present invention as long as those skilled in the art can arbitrarily select them. It is.

  FIG. 4 is a wiring diagram for explaining a method by which the power supply apparatus 115 supplies power to the IP telephone 33 based on POE. In the switching hub 117, only the PHY chip 151, the power supply circuit 152, the transmission transformer 153, and the reception transformer 154 are shown. The transmission transformer 153 and the reception transformer 154 are provided to protect the PHY chip 151 from a high voltage entering through the UTP cable 41. The power supply circuit 152 distributes the electric power supplied from the power supply apparatus 115 to elements that operate inside the switching hub 117.

  The transmission transformer 153 and the reception transformer 154 are connected to the RJ45 connector 125 through twisted pairs 155 and 156, respectively. From the switching hub 117 to the IP telephone 33, in order to perform data transmission with 100BASE-TX corresponding to POE, a pair of twisted pairs 155 and 156 are used for transmission and reception, respectively. The power feeding device 115 includes a 48V voltage inputted from the DC / DC converter 113 therein, between the twisted pair 161 and the twisted pair 163, and a twisted pair 157 and a twisted pair of wires. A POE power chip 159 that outputs a voltage of 48V is provided between the POE power chip 159 and the 158. The POE power chip 159 can supply power to the IP telephone according to the POE protocol. The twisted pair 157, 158, 161, 162 transmits only electric power and does not transmit data. Therefore, the twisted pair 157, 158, 161, 162 does not transmit data. You may comprise with conducting wire.

  The twisted pairs 155, 156, 161, 162 are connected to the IP telephone 33 via the FJ45 connectors 125, 165, the UTP cable 41, and the RJ45 connector 167. In the IP telephone 33, only a receiving transformer 169, a transmitting transformer 170, a PHY chip 173, and a power supply circuit 175 are shown. In this embodiment, the power supply circuit 175 is supplied with power from the POE power chip 159 by the option B method, but the transmission transformer 169 can also receive power from the other PSEs by the option A method. , 170 are also connected to the center taps. When power is supplied to the IP telephone 33 using the option A method, a power feeding device is mounted inside the switching hub 117, and 48V is provided between the center taps of the transmission transformer 153 and the reception transformer 154. Supply voltage. The power supply circuit 175 distributes the power supplied from the power supply device 115 to elements operating inside the IP telephone 33.

  Next, the operation of the network system 1 will be described. FIG. 5 is a flowchart showing the operation of the network system 1. In block 201, the LAN 10 shown in FIG. 1 is prepared. The LAN 10 is supplied with power from the UPS 21 during a power failure. In block 203, the RJ45 connector 123 of the function expansion device 100 is connected to the RJ connector 29b by the UTP cable 32, and the IP telephone 33 is further connected to the RJ45 connector 125 of the function expansion device 100 by the UTP cable 41.

  When the AC / DC adapter 103 is connected to the power connector 105, the power failure detection circuit 121 detects the voltage and turns on the FET 119. The DC / DC converters 113, 109, 61 are supplied with power from the AC / DC adapter 103, and the DC / DC converter 113 supplies power to the power feeding device 115. Based on the auto-negotiation function, the switching hub 117 exchanges a signal called “Fast Link Pulse” with the IP telephone 33, exchanges information about communication modes supported by each other, and performs priority resolution ( Priority Resolution) is used to set the port to the fastest communication mode. In this case, the switching hub 117 sets the port for the IP telephone 33 to the communication speed defined in the 100BASE-TX standard. In this state, the IP telephone 33 is connected to the LAN 10 via the switching hub 117, and is connected to the LAN 10 via the IP gateway 17 and the public telephone line 13. Can be used for calls with other telephones.

  The power feeding device 115 supplies power to the IP telephone 33 and the switching hub 117. When the IP telephone 33 is connected to the RJ45 connector 125, the POE power chip 159 applies a low voltage of 2.8V to 10V to the IP telephone 33 to execute the detection mode. A 25Ω resistor is inserted in the IP telephone 33 corresponding to the POE, and a current corresponding to the applied voltage flows between the twisted pair 161 and the twisted pair 162. When the POE power chip 159 detects that the resistance value is 25Ω from the relationship between the applied voltage and the flowing current, it shifts to the classification mode. If the resistance value cannot be recognized as 25Ω, it is determined that the IP telephone 33 does not support POE and power is not supplied.

  In the classification mode, the POE power chip 159 applies a voltage of 15.5 V to 20.5 V to the IP telephone 33, measures the flowing current, and determines the power consumption of the IP telephone 33 based on the value. When classification is completed, the POE power chip 159 supplies power to the IP telephone 33. When the IP telephone 33 is disconnected from the RJ connector 125, the POE power chip 159 stops supplying power. Since the switching hub 117 does not support POE, the POE power chip 159 supplies a voltage of 48V without using the POE procedure.

  Since there is a possibility that non-POE-compatible devices may be connected to the RJ connector 125, it is necessary to supply power based on the POE protocol. However, such a problem occurs for the switching hub 117. Absent. Since power is supplied from the power supply device 115 to the IP telephone 33, it is not necessary to supply power from an independent AC / DC adapter. Further, since power is supplied to the switching hub 117 from the AC / DC adapter 103, it is not necessary to connect an independent AC / DC adapter. Since the function expansion device 100 is disposed on the desk 39 for the purpose of using the notebook PC 35 in a state equivalent to a desktop, the space on the desk can be saved as compared with the case where an independent switching hub is provided. it can.

  In block 205, the notebook PC 35 is attached to the function expansion device 10. Power is supplied from the AC / DC adapter 103 to the system load 59 of the notebook PC 35, the charger 57, and the system load 111 of the function expansion device 100, and the user expands the notebook PC 35 while charging the battery pack 67. Can be used with. Since no POE is adopted between the switching hub 25 and the switching hub 117, data transmission can be performed according to the standard of 1000BASE-T. The notebook PC 35 can transmit data to and from the LAN 10 without being restricted by the transmission speed of the IP telephone corresponding to POE. Based on the auto-negotiation function, the switching hub 117 sets the port for the Ethernet controller 65 to the communication speed defined in the 1000BASE-T standard.

  In block 207, when the commercial power supply to which the AC / DC adapter 103 is connected goes out of power or the AC / DC adapter 103 is disconnected from the power connector 105, the notebook PC 35 sounds a buzzer to notify the user and the power outage. The detection circuit 121 turns off the FET 119. When power is not supplied from the AC / DC adapter 103 to the function expansion device 100, the notebook PC 35 is not to use the function expansion device 100. When the notebook PC 35 attached to the function expansion device 100 detects that the voltage of the AC / DC adapter 103 has decreased by a circuit (not shown), the notebook PC 35 shifts to a hibernation state or a suspend state. In block 209, the battery pack 67 supplies power to the DC / DC converter 113, so that the switching hub 117 and the IP telephone 33 can continue to operate. When the voltage of the battery pack 67 falls below a predetermined voltage value set based on the discharge end voltage, the notebook PC 35 sounds a buzzer to notify the user, thereby preventing the IP telephone 33 from being unintentionally disabled. It is out. Since the LAN 10 is supplied with power from the UPS 21, the telephone call of the IP telephone 33 is ensured even during a power failure.

  At this time, since the FET 119 is turned off, no power is supplied to the DC / DC converter 109, so that the user can continue to use the IP telephone 33 while reducing the consumption of the battery pack 67 as much as possible. In the present embodiment, when the notebook PC 35 is not attached to the function expansion device 100, power is not supplied to the IP telephone 33 at the time of a power failure, but when the user uses the IP telephone 33, the user is in the vicinity of the desk 39. Therefore, it is considered that the notebook PC 35 is attached to the function expansion device 100 at this time. Therefore, the notebook PC 35 is an effective power failure countermeasure for the IP telephone 33. The example in which the UTP cable 31 is used for wiring from the switching hub 25 of the LAN 10 to the place where the personal network system 30 is constructed has been shown so far. The present invention is based on the standard of 1000BASE-SX or 1000BASE-LX. You may make it connect with the optical fiber cable of a suitable communication system. Further, the function expansion device 100 may be connected to the access point 23 by a high-speed wireless LAN.

  Although the present invention has been described with the specific embodiments shown in the drawings, the present invention is not limited to the embodiments shown in the drawings, and is known so far as long as the effects of the present invention are achieved. It goes without saying that any configuration can be adopted.

1 ... Network system 10 ... LAN
30 ... Personal network system 31, 41 ... UTP cable 69, 123, 125, 165, 167 ... RJ45 connector 115 ... Power feeding device 155, 156, 157, 158, 161, 162 ... Twisted pair 159 ... POE power chip

Claims (15)

A personal network system connectable to a local area network,
A switching hub that do not conform to the can send and receive data at a transmission rate of the first standard between the local area network Power over Ethernet standard, adapted to the power over Ethernet standards A function including a power supply device to be connected, a first connector connected to the first port of the switching hub and the power supply device, and a second connector connected to the second port of the switching hub An expansion unit;
Sending and receiving data at a transmission rate of the slower than the first standard second standard between connected to said first connector adapted to the Power over Ethernet standard the local area network IP phone that can
Sending and receiving data to and from the local area network at a transmission rate of a third standard faster than the second standard when connected to the function expansion device and connected to the second connector. Personal network system with portable computer including Ethernet controller capable.   The personal network system according to claim 1, wherein the power supply device receives power from an AC / DC adapter connected to the function expansion device and supplies power to the IP telephone.   3. The personal network system according to claim 1, wherein the power supply apparatus is supplied with electric power from a battery mounted on the portable computer during a power failure.   The personal network system according to claim 3, wherein the power supply device supplies power to the switching hub.   The personal network system according to any one of claims 1 to 4, wherein the first standard and the third standard are 1000BASE-T.   6. The personal network system according to claim 1, wherein the switching hub operates in a layer 2 of an OSI reference model.   The personal network system according to claim 6, wherein the second standard is 100BASE-TX. The function expansion device used in a personal network system comprising a portable computer including an Ethernet controller, a function expansion device equipped with the portable computer, and an IP telephone,
A first port that transmits and receives data to and from a local area network at a transmission rate of the first standard, and a transmission rate of a second standard that is slower than the first standard between the IP telephone and the first telephone. A second port capable of transmitting and receiving data, and a third port capable of transmitting and receiving data to and from the Ethernet controller at a transmission rate of a third standard faster than the second standard. Including a switching hub that does not meet Power over Ethernet standards ,
A power supply device that conforms to the power over Ethernet standard and supplies power to the IP telephone;
A function expansion device having   The function expansion device according to claim 8, wherein the power supply device supplies power to the switching hub.   The function expansion device according to claim 8, further comprising a connection terminal of an AC / DC adapter that supplies power to the power supply device and the portable computer.   The function expansion according to claim 10, further comprising a power supply circuit for supplying power from the battery to the power supply device when the portable computer is equipped with a battery and power supply from the AC / DC adapter is stopped. apparatus.   The function expansion device according to claim 11, further comprising a switch for stopping power supply from the battery to a system load of the function expansion device while power is supplied from the battery to the power supply device.   The function expansion device according to claim 8, wherein the first standard and the third standard are the same. A portable computer capable of transmitting and receiving data at the transmission rate of the first standard, and data transmission and reception at the transmission rate of the second standard that conforms to the Power over Ethernet standard and is slower than the first standard A communication method in an IP phone capable of
The function expansion device of the portable computer, compatible with the switching hub that do not match the data transmission possible the power over Ethernet standards between the local area network the Power over Ethernet standard Preparing a power supply device;
Connecting said function expansion device on the local area network,
Connecting the portable computer and the IP telephone to the function expansion device;
Transmitting data between the local area network and the portable computer at the transmission rate of the first standard;
And a method of transmitting data between the local area network and the IP telephone at a transmission rate of the second standard while supplying power to the IP telephone from the power supply apparatus. Supplying power from the AC / DC adapter connected to the function expansion device to the power supply device;
The function expansion device detecting a power failure;
The communication method according to claim 14, further comprising a step of supplying power to the power feeding device from a battery mounted on the portable computer in response to detection of a power failure.

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