Electrical computers and digital processing systems: support – Multiple computer communication using cryptography – Protection at a particular protocol layer
Reexamination Certificate
1998-08-28
2002-07-16
Hayes, Gail (Department: 2131)
Electrical computers and digital processing systems: support
Multiple computer communication using cryptography
Protection at a particular protocol layer
C713S310000
Reexamination Certificate
active
06421782
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an expansion unit on which an information processing system, such as a personal computer, is mounted to expand its functions and, in particular, to an expansion unit that provides a LAN connection environment for an information processing system. More specifically, the present invention pertains to an expansion unit that provides a WOL (Wake-up On LAN) function that ensures security (prevention from illegal access through a network) for an information processing system.
2. Prior Art
Recently, the term “network computing” is frequently appearing in a variety of media, such as newspapers and magazines.
“Network computing” as is literally defined, is an environment wherein a plurality of computers and peripheral devices are connected through a communication medium (either by wire or wireless). The “network” is a communication network for exchanging data between computers. The form of network varies from a local network, such as a LAN (Local Area Network), to a wide range network, such as a public switched telephone network (PSTN), and to the “Internet,” which is a huge, global network as the result of the interconnection of servers. A computer system that serves as DTE (Data Terminal Equipment) is connected to a network through a DCE (Data Circuit Terminal Equipment). The DCE is a modem (Modulator/Demodulator) for an analog network, such as the PSTN, or a TA (Terminal Adapter) for an ISDN (Integrated Services Digital Network), or a LAN adapter (e.g., an ethernet card or a token ring card) for a LAN. The DTE is a dedicated terminal connected to the network through the DCE, or may be a general purpose computer system (e.g., IBM PC/AT compatible machine [“PC/AT” is a trademark of IBM Corp]).
A LAN is a network that is voluntarily managed by an independent association, such as a university or an institute, and is a minimum network unit covering only a relatively small area, such as an in-house area. As LANs have been supported by reductions in prices of communication devices and the enhancement of communication software, which have been accompanied by the developments of semiconductor techniques, LANs have come to be widely employed in the development and research environments for the sharing of computer resources and the sharing and distribution of information.
There are two forms of LANs: a peer-to-peer-based LAN and a client-server-based LAN. For a peer-to-peer-based LAN, The DTEs that are linked together are equals and can share their resources; a user at a specific DTE can use a disk or a printer owned by another LAN user. For a client-server-based LAN, one machine on the LAN serves as a dedicated server and is used in common by other LAN users (i.e., clients). In a client-server-based LAN, a server that provides a service and a client that receives the service perform synchronized processing by using a remote procedure call (RPC).
Lately, the client-server-based method, whereby general-purpose computers (PCs) are linked together, has become the main computing network system, partially because of the following advantages it offers.
(1) Since necessary software is installed for each client PC, individual users can perform their desired jobs.
(2) Data or files to be used in common are loaded in a server, and use of a printer connected to the server can be shared by the users on the network.
(3) Software, such as groupware, is installed in a server, and a process can be performed corresponding to that performed by a workgroup.
However, since information is excessively distributed on the client side (i.e., the sizes of the clients are too much increased), a problem has arisen in that on the client side an enormous amount of money is required for the maintenance and the management of the system. For example, each time the version of an OS or an application is upgraded, much time and effort must be expended for the installation and setup of each PC. A reduction in the general costs associated with a network; i.e., the total cost of ownership (TCO), is an urgent necessity.
To reduce the TCO, one idea is to centralize at the server; the management of the software resources on the network. In this case, for example, only a program located at the server would have to be updated in order to automatically update programs used by the clients. By centralizing the management at the server, the occurrence of problems due the operating errors of clients can be prevented, and the management costs; i.e., the TCO, can be reduced.
A method by which to reduce the TCO involves the employment of a WOL; i.e., a “Wake-up ON LAN” to control the system configuration of clients through a network. At night, when an office is unoccupied, individual client systems on a network that are in the power-off state are automatically activated, so that new applications can be installed in the individual systems and old applications can be updated or replaced.
To implement the WOL, a DCE to be linked with a network; i.e., a LAN, must include the WOL function. When a DTE, a user's terminal, is a general-purpose computer, the DCE is provided in the form of a LAN adapter card. The adapter card can generally be plugged into one of the bus slots on a computer (motherboard). Implementation of the WOL function is accomplished by another function that automatically activates a computer system through a network; i.e., through the LAN.
As the employment of computer systems has spread, attention has come to be focused on the security problem. While various types of electronic apparatuses, such as notebook PCs, are now more compactly made and are light and more easily carried, as a side effect of those advantages, the apparatuses are more susceptible to theft and illegal use. To prevent physical theft, various locking mechanisms are provided for the apparatuses. A mechanism using a so-called “Kensington lock” is a typical example. The “Kensington lock” is disclosed in, for example, U.S. Pat. No. 5,381,685 (Japanese Patent Publication No. Hei 6-511297), but since the locking is not directly related to the present invention, no further explanation for it will be given.
The security problem with computer systems is not only at the physical level, but has been expanded and now also constitutes a software problem not recognized or addressed in the prior art, in that data are illegally copied or destroyed as the result of unauthorized system accesses. When the above described WOL function is employed, for example, an unauthorized skillful user could arbitrarily enter a client system by remote control during a time period in which an office is unoccupied, and use the computer system illegally. In other words, for security, a computer system incorporating the WOL function requires another function for limiting the automatic activation of the system through the LAN.
OBJECTS OF THE INVENTION
It is, therefore, one object of the present invention to provide a superior expansion unit that provides a LAN connection environment for an information processing system mounted thereon, and an information processing system to be mounted on such an expansion unit.
It is another object of the present invention to provide a superior expansion unit that provides a WOL (Wake-up On LAN) function that ensures the security (the protection from unauthorized access through a network) of an information processing system, and an information processing system to be mounted on such an expansion unit.
It is an additional object of the present invention to provide a superior expansion unit that implements a WOL security function for notebook PCs in a multi-user environment wherein one expansion unit is used in common by an unspecified number of notebook PCs, and an information processing system to be mounted on such an expansion unit.
It is a further object of the present invention to provide an expansion unit that implements a WOL security function at a low cost in a multi-user environment wherein one expansion unit is used in common by an unspecified number of not
Nomura Masahiko
Yanagisawa Takashi
Cockburn Joscelyn G.
Hayes Gail
Revak Christopher A.
LandOfFree
Expansion unit for differentiating wake-up packets received... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Expansion unit for differentiating wake-up packets received..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Expansion unit for differentiating wake-up packets received... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2843129