As home networks become more prevalent, so too does the need for centralized storage of data within the home. A home network attached storage device is a standalone device that couples to all the computer systems of the home by way of the home network, and the network attach storage device provides centralized data storage within the home. The centralized storage capacity of a home network attached storage device, while large, is also finite, and as additional storage space is needed the home user may be relegated to purchase and installation of a second home network attached device; however, having two (or more) home network attached storage devices forces the home users to be aware of which “centralized data storage” device stores particular data, and may further force the home user to manually migrate data to keep related data on the same storage device.
For a detailed description of exemplary embodiments of the invention, reference will now be made to the accompanying drawings in which:
Certain terms are used throughout the following description and claims to refer to particular system components. As one skilled in the art will appreciate, computer companies may refer to a component by different names. This document does not intend to distinguish between components that differ in name but not function. In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . .”
Also, the term “couple” or “couples” is intended to mean either an indirect, direct, optical or wireless electrical connection. Thus, if a first device couples to a second device, that connection may be through a direct electrical connection, through an indirect electrical connection via other devices and connections, through an optical electrical connection, or through a wireless electrical connection.
The following discussion is directed to various embodiments. Although one or more of these embodiments may be preferred, the embodiments disclosed should not be interpreted, or otherwise used, as limiting the scope of the disclosure, including the claims. In addition, one skilled in the art will understand that the following description has broad application, and the discussion of any embodiment is meant only to be exemplary of that embodiment, and not intended to intimate that the scope of the disclosure, including the claims, is limited to that embodiment.
The home networking system 100 of
Because each home network server 20 is designed to act as a server for the home networking system 100, and possibly to reduce cost, in accordance with at least some embodiments at least one home network server 20 does not support direct coupling of a display device and/or keyboard. Thus, in some embodiments at least one home network server 20 does not comprise a graphics controller that would couple to a display, and also does not comprise an input/output (I/O) controller that would couple to I/O devices such as a keyboard and mouse. To the extent administration is performed on each home network server 20, the administration may be done remotely using computer systems (e.g., desktop computer 10 or portable computer 16) in the home networking system 100.
Main memory array 26 couples to the host bridge 28 through a memory bus 32. The host bridge 28 comprises a memory control unit that controls transactions to the main memory 26 by asserting control signals for memory accesses. The main memory array 26 functions as the working memory for the processor 24 and comprises a memory device or array of memory devices in which programs, instructions and data are stored. The main memory array 26 may comprise any suitable type of memory such as dynamic random access memory (DRAM) or any of the various types of DRAM devices such as synchronous DRAM (SDRAM), extended data output DRAM (EDODRAM), or Rambus DRAM (RDRAM).
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Home network server 20 further comprises a drive controller 46 coupled to the south bridge 34 by way of the illustrative PCI bus 38. In alternative embodiments, the drive controller may couple to the primary expansion bus 36, or any other currently available or after-developed expansion bus. The drive controller 46 controls the non-volatile memory 48 of a long term storage device, such as a hard disk drive or optical drive. The term non-volatile memory may be alternatively referred to as a file storage location, storage space or storage capacity. In some embodiments, the home network server 20 implements a single long term storage device where computer systems of the home network can store and retrieve data and programs. In alternative embodiments, the home network server implements a redundant array of independent (or inexpensive) drive (RAID) system where the data and instructions written to the home network server 20 are duplicated across non-volatile memory devices to implement fault tolerance.
Also coupled to the illustrative PCI bus 38 is a network interface (NI) 50. The network interface 50 enables the home network server 20 to communicate with computer systems on the home networking system 100 (through the router 14, both of
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In accordance with the various embodiments, home network servers 20A and 20B are configured to determine when a home network server has been newly installed in the home networking system 100, and the determination may take many forms. In some embodiments, at least one home network server 20 is configured to periodically scan locally coupled devices (i.e., devices coupled to the network 11) for the presence of previously unidentified home network servers. In other embodiments, each home network server 20 is configured to, as part of initial installation, send one or more network messages within the network 11 identifying itself as newly installed.
Regardless of the precise mechanism by which home network servers 20A and 20B identify each other within the home networking system 100, each home network server 20 is further configured to, as between the home network servers in the home networking system, select a primary server. The primary server becomes the single point of contact for computer systems in the home networking system for file operations. Selecting the primary server likewise may take many forms. In some embodiments, a user of a home network server is presented an option to manually select one of the home network servers as the primary server. In other embodiments, the selection of the primary server is accomplished without user input. Some illustrative examples of selection of a primary server are: each server generates a random number, and server with the highest number becomes the primary server; some or all the serial number of each server is compared, with the server with lowest serial number becoming primary server; or the server already existing within the home networking system is selected as the primary server, and additional servers are designated secondary servers. Moreover, the home network server selected as primary need not remain constant, and in fact the primary server may change periodically (either automatically, or based on a user selection), or when the primary server fails.
In accordance with the various embodiments, the primary server is the primary point of contact for file operations by computer systems in the home network system. The term “file operations” encompasses all file operations (e.g., file read, file write, file move, and file delete); however, the remaining portions of the specification are directed to file read and file write operations, as these operations are the primary operations implemented by home network servers. Consider first a request by one of the computer systems 10, 16 of the home networking system 100 to write a file to non-volatile memory. In accordance with the various embodiments, the requested location for storage of the file (e.g., F:\server\dadfiles\myfirstfile.doc) and the file are sent to the primary server over the network 11, and received over the primary server's network interface 50. The primary server has two options: store the file on its local non-volatile memory 48 or store the file on the non-volatile memory of a secondary server. In the event there is sufficient storage capacity on the non-volatile memory 48 of the primary server, and/or the primary server elects to store the file locally, the file is written to the non-volatile memory 48. If there is insufficient storage capacity on the non-volatile memory 48, and/or the primary server elects to store the file on a secondary server, the primary server makes a notation as to the location of the file (e.g., in a database or table) and forwards the file using its network interface 50 over the network 11 to a secondary server. The secondary server receives the file over the network 11 and through its network interface 50, and stores the file on the non-volatile memory of the secondary server. Thus, home networking system 100 uses the same network 11 as both the mechanism to send file operation requests from computer systems 10, 16 to home network servers 20, and also as the network on which storage commands are communicated between home network servers 20.
The actual name and location of the stored file need not be as indicated by the requesting computer system. With respect to files stored in the non-volatile memory of the primary server, the file may indeed be in the requested directory and with the requested name, or the file may be stored in any convenient location in the non-volatile memory with any name (with the notation in the database or table correlating the requested name to the actual name). Likewise with respect to storage of the file on the non-volatile memory of the secondary server, the file may be in the requested directory with the requested name, or the file may be stored in any convenient location in the non-volatile memory with any name. In the case of storage on the secondary server, the notation in the database or table of the primary server may be the primary tracking mechanism, and thus in some embodiments secondary server stores the file at a location requested by the primary server without knowing the location or name requested by the requesting computer system. In embodiments where the secondary server may take over as the primary server, the database or table that correlates file names to actual storage locations may be maintained at both the primary and secondary servers.
Now consider a request by one of the computer systems 10, 16 of the home networking system 100 to be provided a file stored on the one of the home network servers 20. In accordance with the various embodiments, the requested location/name of the file (e.g., F:\server\dadfiles\myfirstfile.doc) is sent to the primary server. The primary server may or may not have the file stored on its non-volatile memory, and thus the primary server determines whether the requested filed is stored on its non-volatile memory. In some embodiments, the determination is made by inspecting the non-volatile memory at the requested location (in this example F:\server\dadfiles\). In other embodiments, the primary server consults the database or table to determine if the requested file is locally stored. In the event the file is locally stored, then the primary server sends the file to the requesting computer system.
In the event the requested file is not stored on the non-volatile memory of the primary server, but is instead stored on a secondary server (e.g., determined by consulting the database or table), then the primary server sends a request to the secondary server to provide the file. Providing the file by the secondary server may take several forms. In some embodiments, the secondary server forwards the requested file to the primary server, and the primary server in turn forwards the requested file to the requesting computer system. In yet other embodiments, when the primary server sends a command to the secondary server to provide the file, the primary server also sends an indication of the requesting computer system. Thus, in some embodiments the secondary server forwards the file directly to the requesting computer system.
Utilizing a system as described provides a seamless mechanism to add storage capacity to the home network system 100 without concern regarding actual locations of files. Files may appear to reside within the same drive and directory, yet in actuality the file locations may span different home network servers. Consider, for example, that a primary server has limited additional non-volatile memory, but the primary server stores the file F:\server\dadfiles\myfirstfile.doc. Now consider that a user of one of the computer systems 10, 16 desires to store a second file in the same directory, such as F:\server\dadfiles\mysecondfile.doc. Because of the limited storage capacity of the primary server, the “mysecondfile.doc” may be stored on a secondary server, but from the perspective of the user of the computer systems 10, 16 the files are in the same drive and directory.
Implementation of the various embodiments discussed above may take many forms. In some embodiments, fulfilling file operations as discussed may be implemented as part of the operating system executed on each home network server 20. That is, file operation requests received by a home network server 20 are passed to a portion of the operating system. The operating system, in turn, acts as a primary server or a secondary server to fulfill the file operations as discussed above. In yet other embodiments, fulfilling file operation requests as discussed above is accomplished by a user-level program operating within the home network server, but not as part of the operating system. The user-level program makes the determinations as to file storage locations, and passes only file-level operations to the operating system.
From the description provided herein, those skilled in the art are readily able to combine software created as described with appropriate general purpose or special purpose computer software to create a computer system and/or computer subcomponents in accordance with the various embodiments, to create a computer system and/or computer subcomponents for carrying out the methods of the various embodiments and/or to create a computer-readable media for storing a software program (e.g., an operating system) to implement the method aspects of the various embodiments.