Expansion unit for differentiating wake-up packets received in an information processing system

• US 6,421,782 B1
• Filed: 08/28/1998
• Issued: 07/16/2002
• Est. Priority Date: 09/04/1997
• Status: Expired due to Fees

• Current Assignee: Lenovo Singapore Pte Limited (Lenovo Group Ltd.)
• Original Assignee: International Business Machines Corporation
• Inventors: Yanagisawa, Takashi, Nomura, Masahiko
• Primary Examiner(s): Hayes, Gail
• Assistant Examiner(s): Revak, Christopher A.
• Application Number:
  US09/143,140
• Time in Patent Office: 1,418 Days
• Field of Search: 713/200, 713/201, 713/310, 713/320, 713/321, 713/322, 713/323, 713/324, 713/330, 713/340, 709/227, 709/229, 710/2, 710/15, 710/17, 710/18, 710/19, 710/72, 710/73, 710/129, 710/130, 710/200
• US Class Current: 726/4
• CPC Class Codes: G06F 1/1632 External expansion units, e.g. docking stations
• CPC Class Codes: G06F 1/3209 Monitoring remote activity, e.g. over telephone lines or network connections
• CPC Class Codes: H04L 12/12 Arrangements for remote connection or disconnection of substations or of equipment thereof
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

To provide an expansion unit that implements a WOL (Wake-On-LAN) security function at a low cost in a multi-user environment wherein one expansion unit is used in common by an unspecified number of notebook PCs. An expansion unit includes a LAN adapter having WOL function for connection to a LAN. Since power is constantly supplied to the LAN adapter by an auxiliary power source, the LAN adapter asserts a WOL signal in response to the receipt through the LAN of a wake-up packet. Since a WOL status register and a logic circuit are provided for the expansion unit, network security is ensured for the information processing system. The information processing system can issue an instruction to permit or to inhibit a WOL by writing a predetermined value in the WOL status register. Upon receipt of a WOL signal from the LAN adapter, the logic circuit refers to the WOL status register. When a wake-up is permitted, the logic circuit issues a power-on operation to a notebook PC, and when a wake-up is inhibited, the logic circuit ignores the WOL signal and inhibits the WOL function.

Claims

1. An expansion unit for expanding the function of an information processing system when mounted thereon, comprising:

a communication network adapter for connecting the expansion unit to a communication network and for generating a wake up signal in response to the receipt of a wake-up packet via the network;

a wake up status register for storing a status indicating whether or not a wake-up through the network is permitted;

first means for setting the wake up status register to a state permitting wake up through the communication network when a mounted information processing system is disconnected from the expansion unit or when the mounted information unit performs an I/O operation or when the expansion unit is initialized;

second means responsive to a control signal provides by a mounted information processing system for setting the wake up status register to one of at least two states indicated by the control signal provided by the information processing system; and

,

logic circuit means responsive to the receipt of a wake up packet received via the communication network for generating a power on signal if the wake-up status register indicates that wake up through the network is permitted, and for ignoring the receipt of the wake up packet when the status indicates that wake-up through the network is inhibited.

2. An expansion unit as set forth in claim 1 having an information processing system mounted therein, said information processing system including:

a non-volatile storage means for storing at least two security codes; and

means responsive to a power on signal from the expansion unit for examining the non-volatile storage means and for executing a power on operation when the non-volatile storage means stores a first code indicating no security and for disregarding the power-on signal when the non-volatile storage stores a second code indicating secure operation.

3. An expansion unit for expanding the function of an information processing system when mounted thereon, comprising:

a LAN adapter for connecting the expansion unit to a LAN and for generating a wake up signal in response to the receipt of a wake-up packet via the LAN;

a WOL status register for storing a status indicating whether or not a wake-up through the LAN is permitted;

first means for setting the WOL status register to a state permitting wake up through the LAN when a mounted information processing system is disconnected from the expansion unit or when a mounted information processing system performs an I/O operation or when the expansion unit is initialized;

second means responsive to a control signal provided by a mounted information processing system for setting the WOL status register to one of at least two states indicated by the control signal provided by the information processing system; and

,

logic circuit means responsive to the receipt of a wake up packet received via the LAN for generating a power on signal if the wake-up status register indicates that wake up through the LAN is permitted, and for ignoring the receipt of the wake up packet when the status indicates that wake-up through the LAN is inhibited.

4. An expansion unit as set forth in claim 3 having an information processing system mounted therein, said information processing system including:

a non-volatile storage means for storing at least two security codes; and

means responsive to a power on signal from the expansion unit for examining the non-volatile storage means and for executing a power on operation when the non-volatile storage means stores a first code indicating no security and for disregarding the power-on signal when the non-volatile storage stores a second code indicating secure operation.