Secure system for remotely waking a computer in a power-down state

• US 6,493,824 B1
• Filed: 02/19/1999
• Issued: 12/10/2002
• Est. Priority Date: 02/19/1999
• Status: Expired due to Fees

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Compaq Information Technologies Group LP (HP Inc.)
• Inventors: Crisan, Adrian, Novoa, Manuel
• Primary Examiner(s): Hayes, Gail
• Assistant Examiner(s): Arani, Taghi T.
• Application Number:
  US09/253,637
• Time in Patent Office: 1,390 Days
• Field of Search: 709/250, 709/245, 709/229, 709/225, 713/200, 713/201
• US Class Current: 713/162
• CPC Class Codes: H04L 12/12 Arrangements for remote connection or disconnection of substations or of equipment thereof
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

A secure system and method is provided for remotely waking a computer from a power down state. In one embodiment, a network interface card receives incoming data packets via a network connector. A control module is coupled to the network connector and is configured to search the incoming packets for a wake-up pattern. The control module also verifies that the packet'"'"'s destination address matches the destination address of the network interface card. If the destination addresses match and a wake-up pattern is found, the control module decrypts an encrypted value from the incoming packet and compares the result to an expected value. A successful comparison causes the control module to assert a signal to wake up the host computer. Preferably, a standard public/private key pair encryption scheme is used, and the source of the data packet encrypts the expected value with a private key. All computers which may receive wake-up packets are provided with a public key with which to decrypt values contained in a security field of any wake-up packets. A successful decryption serves to certify that the wake-up packet was transmitted from an authorized source. For added security, the expected value and public/private keys may be changed on a regular basis, or even every time a valid wake-up packet is received. The new value may be provided in the wake-up packet, to be stored by the network card for the next use.

Claims

1. A method for secure remote wake-up of a computer by a network interface card included in the computer, wherein the method comprises:

receiving a data packet from a network;

comparing a destination address included in the data packet to a destination address of the network interface card;

determining if a wake-up pattern is present in the data packet;

decrypting an encrypted value from the data packet to obtain a decrypted value; and

asserting a wake-up signal if the destination addresses match, a wake-up pattern is present, and the decrypted value matches an expected value, wherein the expected value includes a current date;

retrieving a new encryption key included as part of the data packet if the destination addresses match, a wake-up pattern is present, and the decrypted value matches an expected value; and

storing the new encryption key.

2. The method of claim 1, wherein the wake-up signal is an interrupt to a computer processor.

3. The method of claim 1, further comprising:

waking up the computer from a power down state in response to the wake-up signal.

4. The method of claim 1, further comprising:

creating the data packet with a wake-up pattern, wherein the creating includes;

encrypting the expected value using a private encryption key to produce the encrypted value; and

placing the encrypted value in a security field subsequent to the wake-up pattern; and

transmitting the data packet on the network.

5. The method of claim 1, wherein the new encryption key is changed each time the computer is remotely awakened.

6. A network interface card which comprises:

a network connector configured to receive incoming packets;

a control module coupled to the network connector and configured to determine if an incoming packet includes a wake-up pattern, configured to compare a destination address included in the packet to a destination address of the network interface card, and configured to decrypt an encrypted value from a security field in the incoming packet to obtain a decrypted value, wherein the control module is further configured to assert a wake-up signal if the addresses match, a wake-up pattern is included in the packet, and the decrypted value matches an expected value; and

a memory coupled to the control module and configured to store a public encryption key for decrypting the encrypted value,

wherein the control module includes a real-time clock for determining the expected value.

7. The network interface card of claim 6, wherein the wake-up pattern comprises sixteen consecutive repetitions of the network interface card'"'"'s destination address.

8. A networked computer system comprising:

a local computer;

a network coupled to the local computer to transport data packets generated by the local computer;

a remote computer coupled to the network to receive data packets generated by the local computer, wherein the remote computer comprises;

a central processing unit configurable to place the remote computer in a power down mode;

a network interface card coupled between the central processing unit and the network,

wherein while the remote computer is in a power down mode, the network interface card is configured to examine a data packet received from the local computer for a wake-up pattern, configured to compare a destination address included in the received data packet to a destination address of the network interface card, and configured to decrypt an encrypted value from the received data packet to produce a decrypted value, wherein the network interface card is further configured to assert an interrupt to the central processing unit if the received data packet includes a wake-up pattern, the destination addresses match, and the decrypted value equals an expected value, wherein the expected value includes a current date,

wherein the network interface card is further configured to retrieve and store a new encryption key included as part of the data packet if the destination addresses match, a wake-up pattern is present, and the decrypted value matches an expected value.

9. The networked computer system of claim 8, wherein the local computer generates a wake-up packet by encrypting the expected value using a private key according to a public key/private key encryption scheme.

10. The networked computer system of claim 8, wherein the central processing unit is configured to provide the network interface card with one or more suitable wake-up patterns as part of placing the remote computer in a power down mode.

11. A computer readable storage medium which stores software comprising:

a means for receiving a data packet from a network;

a means for comparing a destination address included in the data packet to a destination address of a network interface card;

a means for determining if a wake-up pattern is present in the data packet;

a means for decrypting an encrypted value from the data packet to obtain a decrypted value;

a means for asserting a wake-up signal if the destination addresses match, a wake-up pattern is present, and the decrypted value matches an expected value, wherein the expected value includes a current date; and

a means for retrieving a new encryption key included as part of the data packet if the destination addresses match, a wake-up pattern is present, and the decrypted value matches an expected value; and

a means for storing the new encryption key.