Patent Publication Number: US-2003236853-A1

Title: Method of data reading and writing

Description:
[0001] This application incorporates by reference Taiwan application Serial No. 091113377, filed on Jun. 19, 2002.  
       BACKGROUND OF THE INVENTION  
       [0002] 1. Field of the Invention  
       [0003] The invention relates in general to a method of data reading and writing, and more particularly to a method of accessing a storage medium of a remote device by a local device.  
       [0004] 2. Description of the Related Art  
       [0005] Nowadays, the technology of network computing has been developed to the stage, where a local device can be used to access a remote device, either to read or to write, via the network. However, this method of data access is based on a network supportive operation system (OS), such as Windows operation system. That is, if both a local device and a remote device use a network supportive OS, then the local device can access data in the storage medium of the remote device. The above mentioned local device and the remote device can be a server or a personal computer, and the remote storage medium included in the remote device can be a hard disk drive, floppy disk drive, CD-ROM drive, DVD-ROM drive, Zip drive, or LS-120 drive, and so on.  
       [0006] If the local device adopts an OS which is not a network supportive OS, such as DOS, or the local device has not downloaded a network supportive OS yet, then the data in the remote storage medium cannot be accessed via the network. This is a problem that needs to be solved at this stage of technological development.  
       SUMMARY OF THE INVENTION  
       [0007] It is therefore an object of the invention to provide a method of data reading and writing to access remote data not in an environment of a network supportive OS.  
       [0008] The invention achieves the above-identified objects by providing a method of data reading and writing, which comprises the following steps.  
       [0009] When the Basic Input Output System (BIOS) of a local device downloads an operation system or DOS to access a disk or CD, a service routine in the BIOS is called to execute an action of reading from a floppy disk drive or a CD-ROM drive. The service routine responding to the call from the local device will cancel the original action of accessing the local device, redirect the accessing command and related data, and then pass them to a management program of the local device. Then, the management program send a network packet includes the received accessing command and related data to a remote device via the network. The agent program in the remote device will access the remote storage medium according to the received accessing command and related data, and transfer the requested data back to the management program. Finally, the management program reformats the received data packets into the format suited to the BIOS, and transfers them on to the BIOS. Then, the booting procedure can proceed, or the corresponding programs can be carried out in a DOS system. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0010] Other objects, features, and advantages of the invention will become apparent from the following detailed description of the preferred but non-limiting embodiments. The description is made with reference to the accompanying drawings in which:  
     [0011]FIG. 1 illustrates a method of accessing data from a remote storage medium via the network according to a preferred embodiment of the invention;  
     [0012]FIG. 2 illustrates a system diagram of the local device and the remote device in FIG. 1;  
     [0013]FIG. 3 illustrates a flow chart of a method of writing to a remote storage medium by a local device according to a preferred embodiment of the invention; and  
     [0014]FIG. 4 illustrates a flow chart of a method of reading from a remote storage medium by a local device according to a preferred embodiment of the invention.  
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
     [0015] Referring to FIG. 1, it illustrates a method of accessing data from a remote storage medium via the network according to a preferred embodiment of the invention. The idea of this invention is that when a local device needs to access a local storage medium  10 , such as a local floppy disk, a local CD-ROM, and so on, the accessing command and related data can be redirected, the action of accessing the local storage medium  10  can fail or be cancelled, and the accessing command can be passed to a remote device via the network to execute the action of data access a remote storage medium  110  by a remote agent program  100 , wherein the agent program can be based on the operation system of a remote device. This operation system can be Windows or other network-supportive operation systems. That is, through the function of redirecting the commands, the local device can cancel the original accessing of the local storage medium, and then access the remote storage medium  110  via the network. By this method, a remote storage medium can be easily used to replace a local storage medium, and the object of remote management can then be achieved.  
     [0016] The above idea of this invention can be attained by providing a systematic frame of accessing a remote storage medium via the network, such as shown in FIG. 2. The management program  213  of a local device  21  can pack commands or data from the BIOS into network packets, and send them to the network via a network interface controller (NIC)  215 . Then, those packets can be received by a network interface controller  255  of a remote device  25 . Next, the packets received by the NIC  215  can be reformatted by a management program  213  to suit the BIOS, and be transferred back to the BIOS for further processing, wherein the management program  213  can be a firmware or software to carry it out.  
     [0017] When the BIOS of the local device  21  downloads an operation system, meaning the local device proceeds with a booting procedure, or DOS to access a disk or CD-Rom, a service routine in the BIOS is called to execute the action of accessing a floppy disk drive or a CD-ROM drive. The service routine can be INT 13h for example. In response to the call from the local device  21 , the service routine will cancel the action of accessing the local storage medium and redirect the accessing command and related data to the management program  213 . The management program  213  packs the received accessing command and related data into network packets, and transports them to the remote device  25  via the network. The agent program  100  in the remote device  25  can access the remote storage medium according to the received accessing command and related data, and transfer the obtained data to the management program  213 . At last, the management program  213  reformats the received data to suit the BIOS, and transfers them to the BIOS to proceed with the starting procedure or to execute a related program in DOS.  
     [0018] Referring to FIG. 3, it illustrates a flow chart of a method of writing to a remote storage medium by a local device. When the local device  21  is to write data to a storage medium, the related service routine will be called to execute the action of writing to the floppy disk drive or CD-ROM drive (Step  310 ) At this time, the service routine will cancel the original action of writing to a local storage medium, and redirect the accessing command and related inputted data to the remote device  25  (Step  320 ). Afterwards, the accessing command and inputted data can be packed into network packets and transported to the remote device via the network (Step  330 ). Next, the agent program  100  writes the input data to the remote storage medium  110  according to the accessing command (Step  340 ), and then transfers the writing result back to the BIOS (Step  350 ).  
     [0019] Referring to FIG. 4, it illustrates a flow chart of a method of reading from a remote storage medium by a local device. When the local device  21  is to read data from a storage medium, the related service routine will be called to execute the action of reading from a floppy disk drive or a CD-ROM drive (Step  410 ). At this time, the service routine will cancel the original action of reading from a local storage medium, and redirect the accessing command to the remote device  25  (Step  420 ). Afterwards, the accessing command can be packed into network packets and transported to the remote device via the network (Step  430 ); next, the agent program  100  will read the data from the remote storage medium  110  according to the accessing command (Step  440 ). Then, the read data is packed into network packets and transferred back to the local device (Step  450 ). The management program  213  reformats the received data to suit the BIOS, and transfers them to the BIOS to proceed with the starting procedure or to execute a related program in DOS.  
     [0020] The characteristics of this invention are to redirect the accessing command and related data through a BIOS service routine, to transfer the redirected accessing command and data to the remote device  25  via the network by the management program  213 , to access the remote storage medium  110  according to the received command and data by the agent program  110  of the remote device  25 , to transfer the result and data back to the management program  213 , and then to transfer the information back to BIOS after processing. By this technique, a remote storage medium can be used as a local storage medium by a local device.  
     [0021] As disclosed above, the method of data access provides at least the following advantages:  
     [0022] 1. Remote management: It can be achieved to update a firmware of a local device, such as BIOS, or execute a checking program from a remote end.  
     [0023] 2. Hardware replacement: If there is no floppy disk drive, CD-ROM drive, or other storage medium included in a local device, or those storage media are broken, and there is such a medium in a remote device, then the remote storage medium can be applied to replace the local floppy disk drive or CD-ROM drive.  
     [0024] While the invention has been described by way of example and in terms of the preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiment. To the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures.