Data processing system and method for permitting a server to remotely provide a client computer system's settings password to the client

Information

  • Patent Grant
  • 6601174
  • Patent Number
    6,601,174
  • Date Filed
    Monday, February 22, 1999
    26 years ago
  • Date Issued
    Tuesday, July 29, 2003
    22 years ago
Abstract
A data processing system and method are described for permitting a server computer system to remotely provide a client computer system's settings password to the client computer system. The client and server computer systems are coupled together utilizing a network. A network settings password is established within the client. The network settings password is required prior to permitting access to system settings included within the client. The client receives the network settings password from the server computer system utilizing the network. Access to the system settings is permitted in response to the receipt of the network settings password. In this manner, the server computer system remotely provides a network settings password to the client computer system.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates in general to data processing systems and, in particular, to a data processing system and method including a server and client computer systems coupled together utilizing a network. Still more particularly, the present invention relates to a data processing system and method including a server and client computer systems coupled together utilizing a network for permitting the server to provide a client computer system's settings password remotely to the client computer system.




2. Description of the Related Art




Personal computer systems are well known in the art. They have attained widespread use for providing computer power to many segments of today's modern society. Personal computers (PCs) may be defined as a desktop, floor standing, or portable microcomputer that includes a system unit having a central processing unit (CPU) and associated volatile and non-volatile memory, including random access memory (RAM) and basic input/output system read only memory (BIOS ROM), a system monitor, a keyboard, one or more flexible diskette drives, a CD-ROM drive, a fixed disk storage drive (also known as a “hard drive”), a pointing device such as a mouse, and an optional network interface adapter. One of the distinguishing characteristics of these systems is the use of a motherboard or system planar to electrically connect these components together. Examples of such personal computer systems are IBM's PC 300 series, Aptiva series, and Intellistation series.




With personal computers being increasingly connected into networks to allow transfers of data among computers to occur, more operations such as maintenance, updating of applications, and data collections are occurring over the network. Computer networks are also becoming essential to their users. It is desirable to minimize loss of productivity by increasing availability of network resources. In today's networked world, the availability and performance of the network is as important as the availability and performance of the personal computer.




Passwords are known in the art to protect access to computer systems. A user is required to enter the correct password in order to utilize the computer system. It is also known in the art to require the correct entry of a settings password in order to access and/or change the computer system's settings. The system settings include configuration information, a boot sequence, and a listing of bootable devices. The settings password must also be entered in order to enter setup to clear an error condition which caused an unsuccessful boot. Without the settings password, a user may utilize the computer, but may not access or alter any system settings or the stored system configuration.




An error may occur during a boot of a computer system. For example, the keyboard may become unplugged which results in a failure to boot. In order to enter setup to clear the error resulting from the unplugged keyboard which caused the unsuccessful boot, a user must enter the correct settings password. The settings password is typically known only by a system administrator and not by ordinary computer users. Therefore, to correct or clear the error in the computer system, the system administrator must be physically present at the client computer system to enter the settings password, correct or clear the error, and restart the computer system.




Therefore, a need exists for a data processing system and method for permitting a server computer system to remotely provide a settings password to a client computer system.




SUMMARY OF THE INVENTION




A data processing system and method are described for permitting a server computer system to remotely provide a client computer system's settings password to the client computer system. The client and server computer systems are coupled together utilizing a network. A network settings password is established within the client. The network settings password is required prior to permitting access to system settings included within the client. The client receives the network settings password from the server computer system utilizing the network. Access to the system settings is permitted in response to the receipt of the network settings password. In this manner, the server computer system remotely provides a network settings password to the client computer system.




The above as well as additional objectives, features, and advantages of the present invention will become apparent in the following detailed written description.











BRIEF DESCRIPTION OF THE DRAWINGS




The novel features are set forth in the appended claims. The present invention itself, however, as well as a preferred mode of use, further objectives, and advantages thereof, will best be understood by reference to the following detailed description of a preferred embodiment when read in conjunction with the accompanying drawings, wherein:





FIG. 1

illustrates a pictorial representation of a data processing system including a plurality of client computer systems coupled to a server computer system utilizing a network and a hub in accordance with the method and system of the present invention;





FIG. 2

depicts a pictorial representation of a processing and a network adapter included within a client computer system in accordance with the method and system of the present invention;





FIG. 3

illustrates a pictorial representation of a special purpose processing unit included within a network adapter in accordance with the method and system of the present invention;





FIG. 4

depicts a high level flow chart which illustrates establishing passwords and a password bit within a client computer system in accordance with the method and system of the present invention;





FIG. 5

depicts a high level flow chart which illustrates a client computer system receiving and utilizing a network settings password to boot in accordance with the method and system of the present invention; and





FIG. 6

depicts a high level flow chart which illustrates a server computer system transmitting a network settings password to a client computer system in accordance with the method and system of the present invention.











DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT




A preferred embodiment of the present invention and its advantages are better understood by referring to

FIGS. 1-6

of the drawings, like numerals being used for like and corresponding parts of the accompanying drawings.




The present invention is a method and system for permitting a server computer system to remotely provide a network settings password to a client computer system. The network settings password is a network privileged access password (PAP). A privileged access password (PAP) must be provided to the client, either input manually utilizing the client's keyboard or received utilizing the network, prior to permitting access to the client's system settings. In response to the entry of a correct PAP, access is permitted to the system settings.




An initial copy of the network PAP is stored within the client computer system prior to regular operation of the client. Thereafter, in the event an error occurs during a boot of the client computer system, the client will prompt a user to enter the system PAP when the user attempts to enter setup, and will request a copy of the network PAP from the server. If the user correctly enters the system PAP, the user may access and change system settings as necessary, and may clear the error conditions which caused the boot process to fail.




The server will transmit a copy of the network PAP to the client. A network adapter included within the client will receive the copy of the network PAP and will compare the received copy with the stored initial network PAP. If the two match, a network PAP bit will be set. This bit is read by POST to determine whether a valid network PAP was received. If the bit is set, BIOS enters setup, clears the network PAP bit, and re-boots. If the bit is clear, BIOS will not enter setup.




The initial network PAP is stored within the client in protected storage which may not be read by software executing within the client. The storage location may not be read by POST or BIOS. The storage location may only be read by the network adapter included within the client.




A privileged access password is more fully described in U.S. Pat. No. 5,388,156. The invention described in U.S. Pat. No. 5,388,156 issued on Feb. 7, 1995 to Blackledge held in common ownership with this invention is hereby incorporated by reference.





FIG. 1

illustrates a pictorial representation of a data processing system including a plurality of client computer systems


104


coupled to a server computer system


100


utilizing a hub


102


in accordance with the method and system of the present invention. Server computer system


100


is connected to a hub


102


utilizing a local area network (LAN) connector bus


106


. Respective client systems


104


also connect to hub


102


through respective LAN busses


106


. The preferred form of the network conforms to the Ethernet specification and uses such hubs. It will be appreciated, however, that other forms of networks may be utilized to implement the invention.




A “network” may include any type of data communications channel, such as an Ethernet network, token ring, X.


10


, or X.


25


. Those skilled in the art will recognize that the invention described herein may be implemented utilizing any type of data communications channel. However, the preferred embodiment is implemented utilizing an Ethernet network.





FIG. 2

illustrates a pictorial representation of a processor and a network adapter included within a client computer system in accordance with the method and system of the present invention. A central processing unit (CPU)


200


is connected by address, control, and data busses


202


to a memory controller and peripheral component interconnect (PCI) bus bridge


204


which is also coupled to system memory


206


.




An integrated drive electronics (IDE) device controller


220


and a PCI bus to Industry Standard Architecture (ISA) bus bridge


212


are connected to PCI bus bridge


204


utilizing PCI bus


208


. IDE controller


220


provides for the attachment of IDE compatible storage devices such as fixed disk drive


222


. PCI/ISA bridge


212


provides an interface between PCI bus


208


and an optional feature or expansion bus such as the ISA bus


214


. PCI/ISA bridge


212


includes power management logic. A PCI standard expansion bus with connector slots


210


is coupled to PCI bridge


204


. PCI connector slots


210


may receive PCI bus compatible peripheral cards. An ISA standard expansion bus with connector slots


216


is connected to PCI/ISA bridge


212


. ISA connector slots


216


may receive ISA compatible adapter cards (not shown). It will be appreciated that other expansion bus types may be used to permit expansion of the system with added devices. It should also be appreciated that two expansion busses are not required to implement the present invention.




PCI-ISA bridge controller


212


includes an interface for a flash memory


242


, which includes microcode which client


104


executes upon power-on. Flash memory


242


is an electrically erasable programmable read only memory (EEPROM) module and includes BIOS that is used to interface between the I/O devices and operating system. PCI-ISA bridge controller


212


also includes CMOS storage


213


that holds initialization settings which represent system configuration data. Storage


213


includes values which describe the present configuration of client


104


. For example, storage


213


includes information describing the list of initial program load (IPL) devices set by a user and the sequence to be used for a particular power method, the type of display, the amount of memory, time date, etc. Furthermore, this data is stored in storage


213


whenever a special configuration program, such as configuration/setup is executed. PCI-ISA bridge controller


212


is supplied power from battery


244


to prevent loss of configuration data in storage


213


.




An I/O controller


218


is coupled to PCI-ISA bridge controller


212


. I/O controller


218


controls communication between PCI-ISA bridge controller


212


and devices and peripherals such as floppy drive


224


, keyboard


226


, and mouse


228


so that these devices may communicate with CPU


200


.




Client system


104


includes a video controller


246


which may, for example, be plugged into one of connector slots


210


. Video controller


246


is connected to video memory


248


. The image in video memory


248


is read by controller


246


and displayed on a monitor (not shown) which is connected to client


104


through connector


250


.




A client system


104


includes a network adapter


230


which may, for example, be plugged into one of the PCI connector slots


210


(as illustrated) or one of the ISA connector slots


216


in order to permit client


104


to communicate with a LAN via connector


236


to hub


102


.




Client computer system


104


includes a special power supply


240


which supplies full normal system power


243


, and has an auxiliary power main AUX


5




241


which supplies full time auxiliary power to the power management logic


212


and to the network adapter


230


. This enables client


104


to respond to a wakeup signal from network adapter


230


. In response to a receipt of the wakeup signal, normal system power


243


from power supply


240


is turned on and then powers up client


104


.




Network adapter


230


includes a physical layer


234


and a media access controller (MAC)


232


connected together utilizing a Media Independent Interface (MII) bus


252


. The MII bus


252


is a specification of signals and protocols which define the interfacing of a 10/100 Mbps Ethernet Media Access Controller (MAC)


232


to the underlying physical layer


234


.




MAC


232


processes digital network signals, and serves as an interface between a shared data path, i.e. the MII bus


252


, and the PCI bus


208


. MAC


232


performs a number of functions in the transmission and reception of data packets. For example, during the transmission of data, MAC


232


assembles the data to be transmitted into a packet with address and error detection fields. Conversely, during the reception of a packet, MAC


232


disassembles the packet and performs address checking and error detection. In addition, MAC


232


typically performs encoding/decoding of digital signals transmitted over the shared path and performs preamble generation/removal, as well as bit transmission/reception. In a preferred embodiment, MAC


232


is an Intel


82557


chip. However, those skilled in the art will recognize that the functional blocks depicted in network adapter


230


may be manufactured utilizing a single piece of silicon.




Physical layer


234


conditions analog signals to go out to the network via an R


45


connector


236


. Physical layer


234


may be a fully integrated device supporting 10 and 100 Mb/s CSMA/CD Ethernet applications. Physical layer


234


receives parallel data from the MII local bus


252


and converts it to serial data for transmission through connector


236


and over the network. Physical layer


234


is also responsible for wave shaping and provides analog voltages to the network. In a preferred embodiment, physical layer


234


is implemented utilizing an Integrated Services chip ICS-


1890


.




Physical layer


234


includes auto-negotiation logic that serves three primary purposes. First, it determines the capabilities of client computer


104


. Second, it advertises its own capabilities to server computer


100


. Third, it establishes a connection with server computer


100


using the highest performance connection technology.




Network adapter


230


includes a special purpose processing unit


300


coupled to the MII bus


252


between physical layer


234


and MAC


232


. Logic module


300


may be a “hard wired” application specific integrated circuit (ASIC) or a programmed general-purpose processor which is programmed as more fully described below. By coupling ASIC


300


to the MII bus


252


, ASIC


300


may send and receive network packets using physical layer


234


.




Data from client computer system


104


is accessed by ASIC


300


over a system management bus (SM)


238


. System management bus


238


is a two-wire low speed serial bus used to connect system management devices. This provides a path to allow software running on client


104


to access ASIC


300


. With the trickle power supplied by signal AUX


5




241


from power supply


240


, ASIC


300


is preferably powered full time.





FIG. 3

illustrates a pictorial representation of a special purpose processing unit included within network adapter


230


in accordance with the method and system of the present invention. Special purpose processing unit is implemented utilizing ASIC


300


which includes a micro-controller


302


which includes several state machines to handle the following tasks: packet reception, SM bus interface, and EEPROM updates. Micro-controller


302


sends commands to FIFO control


308


to control data flow from TX FIFO


306


, RX FIFO


310


, and RX Buffer


318


. Micro-controller


302


also responds to SM bus requests through SM bus interface


316


from software running on client


104


to access register status


304


. Signals are received from the MII bus


252


by interface unit


312


and passed to RX FIFO


310


. Micro-controller


302


may access data stored in EEPROM


320


through EEPROM interface


314


.




Register status


304


includes a network PAP bit


330


. Network adapter


230


sets network PAP bit


330


in response to network adapter


230


receiving a network PAP which is the same as an initial network PAP stored in EEPROM


320


in network PAP storage


332


. Network PAP bit


330


remains cleared if the received network PAP is not the same as the stored network PAP


332


. Micro-controller


302


determines the source of a request to access the network PAP stored in EEPROM


330


. If the request came from the network, micro-controller


302


is capable of reading and/or writing to storage


332


. If the request came from SM bus


238


, micro-controller


302


is not capable of reading or writing to storage


332


.





FIG. 4

depicts a high level flow chart which illustrates establishing passwords and a password bit within a client computer system in accordance with the method and system of the present invention. The process starts as depicted by block


400


and thereafter passes to block


402


which illustrates establishing a system privileged access password (PAP). A privileged access password, either the system PAP or network PAP, is required when a user attempts to alter system settings or access restricted functions. The system PAP is input when a user is physically present at the client computer system. The network PAP is downloaded utilizing the network from server to a client.




Next, block


404


depicts establishing a network privileged access password (PAP). The network PAP is received by a client computer system from a server computer system. Users are not aware of the content of network PAP utilized by the client. In addition, software executing within the client, including POST and BIOS, is not aware of the content of network PAP. The network adapter


230


stores a copy of the correct network PAP in protected storage


332


.




Thereafter, block


406


illustrates establishing a network PAP bit. The network PAP bit


330


is preferably implemented in registers status


304


, but may be implemented in other components within client


104


. Software executing within the client may access bit


330


to determine whether the client received a correct copy of the network PAP from the server. If a correct copy was received, bit


330


will be set. If an incorrect copy or no copy was received, bit


330


will remain cleared, or reset. The process then terminates as depicted at block


408


.





FIG. 5

depicts a high level flow chart which illustrates a client computer system receiving and utilizing a network settings password to boot in accordance with the method and system of the present invention. The process starts as illustrated at block


500


and thereafter passes to block


502


which depicts the client receiving a command from the server to enable enhanced security within the client. When enhanced security is enabled, a privileged access password is required in order to access and change system settings. Next, block


504


depicts the client receiving an initial network PAP from the server. The initial network PAP is stored in location


332


within EEPROM


320


. When the client requests a network PAP from the server, it will be compared with the initial network PAP stored in location


332


.




Next, block


506


illustrates a determination of whether or not an error occurred during a boot of the client. If a determination is made that no error occurred, the process passes to block


508


which depicts the continuation of normal processing.




Referring again to block


506


, if a determination is made that an error did occur during a boot of the client, the process passes to block


510


which illustrates BIOS executing within the client detecting the error and attempting to enter setup. This client is configured to require the entry of a correct PAP prior to entering setup.




The process then passes to block


512


which depicts the client sending an alert to the server about the error. Next, block


514


illustrates the client transmitting a message to the server requesting a copy of the network PAP. Thereafter, block


516


depicts the client prompting the user for the system PAP. Block


518


, then, illustrates a determination of whether or not the system PAP was correctly entered. If a determination is made that the system PAP was correctly entered, the process passes to block


520


which depicts BIOS entering setup. A user may then modify the settings to correct the source of the error or in some manner clear the error condition which caused the boot process to fail. The network PAP bit


330


is then cleared. The client is re-booted. The process then passes to block


506


.




Referring again to block


518


, if a determination is made that the system PAP was not correctly entered, the process passes to block


522


which depicts a determination of whether or not the client received a copy of the network PAP. If a determination is made that the client did not receive a copy of the network PAP, the process passes to block


518


.




Referring again to block


522


, if a determination is made that the client did receive a copy of a network PAP, the process passes to block


524


which illustrates network adapter


230


comparing the received copy of a network PAP to the initial network PAP stored in location


332


. Block


526


, then, depicts a determination of whether or not the received copy is the same as the stored copy. If a determination is made that they are the same, the process passes to block


528


which illustrates network adapter


230


setting bit


330


. The process then passes to block


530


.




Referring again to block


526


, if a determination is made that the received PAP is not the same as the stored PAP, the process passes to block


532


which illustrates network adapter


230


leaving network PAP bit


330


cleared. The process then passes to block


530


which depicts POST reading the network PAP bit


330


to determine whether it is set.




Next, block


534


illustrates a determination of whether or not bit


330


is set. If bit


330


is not set, i.e. it is clear, the process passes back to block


518


. Referring again to block


534


, if a determination is made that bit


330


is set, the process passes to block


520


which depicts BIOS entering setup so that the cause of the error may be corrected.





FIG. 6

depicts a high level flow chart which illustrates a server computer system transmitting a network settings password to a client computer system in accordance with the method and system of the present invention. The process starts as illustrated at block


600


and thereafter passes to block


602


which depicts the server transmitting a message to a client to enable security within the client. Next, block


604


illustrates the server transmitting an initial network PAP to the client. Thereafter, block


606


depicts the server receiving an alert about the client encountering an error during booting.




The process then passes to block


608


which illustrates the server receiving a request form the client to transmit a copy of the client's network PAP. A user may contact a help desk which would then request the server to transmit a copy of the client's network PAP. Therefore, this request may be received from the client or from another computer system on the network such as a help desk computer system. Next, block


610


depicts the server transmitting a copy of the client's network PAP to the client. The process then terminates as illustrated at block


612


.




While a preferred embodiment has been particularly shown and described, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the present invention.



Claims
  • 1. A data processing system for permitting a server computer to remotely provide a settings password to a client computer system, said client computer system being coupled to a server computer system utilizing a network, comprising:said server computer system executing code for establishing a network settings password for said client computer system within said server computer system, wherein said network settings password is required prior to permitting access to system settings included within said client computer system; a network adapter within said client computer system capable of receiving said network settings password from said server computer system utilizing said network; said client computer system capable of permitting access to said system settings in response to said receipt of said network settings password, wherein said server computer system remotely provides said network settings password to said client computer system; said client computer system executing code for establishing a local settings password within said client computer system, wherein either said local settings password or said network settings password is required prior to permitting access to system settings included within said client computer system; in response to a failure to boot, said client computer system executing code for requesting said local settings password from a user; in response to a failure of said user to correctly enter said local settings password, said client computer system executing code for requesting said network settings password from said server computer system; and said server computer system executing code for transmitting said network settings password to said client computer system utilizing said network in response to said request from said client computer system.
  • 2. The system according to claim 1, further comprising:said client computer system executing code for storing an initial network settings password within said client computer system prior to regular operation of said client computer system; in response to a receipt of said network settings password from said server, said network adapter executing code for comparing said initial network settings password with said received network settings password; in response to a determination that said initial network settings password and said received network settings password are the same, said client computer system executing code for permitting access to said system settings; and in response to a determination that said initial network settings password and said received network settings password are different, said client computer system executing code for prohibiting access to said system settings.
  • 3. The system according to claim 2, further comprising said client computer system capable of storing said initial network settings password within non-system-accessible storage within said client computer system, said storage being inaccessible to software executing within said client computer system, wherein only said network adapter may access said initial network settings password.
  • 4. The system according to claim 3, further comprising:a network bit within said network adapter capable of being read by software executing within said client computer system; in response to a determination that said initial network settings password and said received network settings password are the same, said client computer system executing code for setting said network bit; and in response to a determination that said initial network settings password and said received network settings password are different, said client computer system executing code for clearing said network bit.
  • 5. The system according to claim 4, further comprising in response to said network bit being set, said client computer system capable of permitting access to said system settings.
  • 6. The system according to claim 5, further comprising in response to accessing said system settings, said client computer system executing code for clearing said network bit.
  • 7. The system according to claim 6, further comprising in response to network bit being set, said client computer system capable of being re-booted.
  • 8. A method in a data processing system for permitting a server computer to remotely provide a settings password to a client computer system, said client computer system being coupled to a server computer system utilizing a network, said method comprising the steps of:establishing a network settings password for said client computer system within said sever computer system, wherein said network settings password is required prior to permitting access to system settings included within said client computer system; said client computer system receiving said network settings password from said server computer system utilizing said network; permitting access to said system settings in response to said receipt of said network settings password, wherein said server computer system remotely provides said network settings password to said client computer system; establishing a local settings password within said client computer system, wherein either said local settings password or said network settings password is required prior to permitting access to system settings included within said client computer system; in response to a failure to boot, said client computer system requesting said local settings password from a user; in response to a failure of said user to correctly enter said local settings password, said client computer system requesting said network settings password from said server computer system; said server computer system transmitting said network settings password to said client computer system utilizing said network in response to said request from said client computer system; storing an initial network settings password within said client computer system prior to regular operation of said client computer system; in response to a receipt of said network settings password from said server, a network adapter included within said client computer system comparing said initial network settings password with said received network settings password; in response to a determination that said initial network settings password and said received network settings password are the same, permitting access to said system settings; and in response to a determination that said initial network settings password and said received network settings password are different, prohibiting access to said system settings.
  • 9. The method according to claim 8, further comprising the step of storing said initial network settings password within non-system-accessible storage within said client computer system, said storage being inaccessible to software executing within said client computer system, wherein only said network adapter may access said initial network settings password.
  • 10. The method according to claim 9, further comprising the steps of:establishing a network bit within said network adapter, said network bit being readable by software executing within said client computer system; in response to a determination that said initial network settings password and said received network settings password are the same, setting said network bit; and in response to a determination that said initial network settings password and said received network settings password are different, clearing said network bit.
  • 11. The method according to claim 10, further comprising the step of in response to said network bit being set, permitting access to said system settings.
  • 12. The method according to claim 11, further comprising in response to accessing said system settings, clearing said network bit.
  • 13. The method according to claim 12, further comprising the step of in response to network bit being set, said client computer system re-booting.
  • 14. A data processing system for permitting a server computer to remotely provide a settings password to a client computer system, said client computer system being coupled to a server computer system utilizing a network, comprising:said server computer system executing code for establishing a network settings password for said client computer system within said server computer system, wherein said network settings password is required prior to permitting access to system settings included within said client computer system; said client computer system executing code for establishing a local settings password within said client computer system, wherein either said local settings password or said network settings password is required prior to permitting access to system settings included within said client computer system; said client computer system executing code for storing an initial network settings password within said client computer system prior to regular operation of said client computer system; said client computer system capable of storing said initial network settings password within non-system-accessible storage within said client computer system, said storage being inaccessible to software executing within said client computer system, wherein only said network adapter may access said initial network settings password; in response to a failure to boot, said client computer system executing code for requesting said local settings password from a user; in response to a failure of said user to correctly enter said local settings password, said client computer system executing code for requesting said network settings password from said server computer system; a network adapter within said client computer system capable of receiving said network settings password from said server computer system utilizing said network; said server computer system executing code for transmitting said network settings password to said client computer system utilizing said network in response to said request from said client computer system; in response to a receipt of said network settings password from said server, said network adapter executing code for comparing said initial network settings password with said received network settings password; in response to a determination that said initial network settings password and said received network settings password are the same, said client computer system executing code for setting said network bit; in response to a determination that said initial network settings password and said received network settings password are different, said client computer system executing code for clearing said network bit; a network bit within said network adapter capable of being read by software executing within said client computer system; in response to said network bit being set, said client computer system capable of permitting access to said system settings; in response to accessing said system settings, said client computer system executing code for clearing said network bit; and in response to network bit being set, said client computer system capable of being re-booted.
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