Method and apparatus for allowing a remote node to awaken a sleeping node of a network

• US 6,049,885 A
• Filed: 06/24/1997
• Issued: 04/11/2000
• Est. Priority Date: 10/20/1994
• Status: Expired due to Term

• Current Assignee: GlobalFoundries, Inc.
• Original Assignee: Advanced Micro Devices, Inc.
• Inventors: Gibson, Glen, Runaldue, Thomas J., Yu, Ching
• Primary Examiner(s): Donaghue, Larry D.
• Application Number:
  US08/881,067
• Time in Patent Office: 1,022 Days
• Field of Search: 709/223, 709/200, 709/238, 709/220, 709/221, 713/323, 713/324, 713/100, 340/825.06, 340/825.07, 340/825.03, 371/2.2, 371/5.3, 371/6, 371/11.1, 371/12, 371/24, 380/3, 380/4
• US Class Current: 713/324
• 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

A system and method for remotely waking up a device connected to a local area network (LAN) is disclosed. A special data packet is disclosed wherein the destination address of the packet is embedded at least 16 consecutive times within the data field of the packet. When this particular type of packet is transmitted on the LAN, it is first decoded by the I/O subsystem of the device to determine whether or not it is a remote wake-up packet. After determining that the packet received is a remote wake-up packet, a wake-up enable line is activated thereby taking the system out of its low power mode, for providing further processing of future received packets.

Claims

1. An awakenable system for use within a uniquely addressable node of a network, said network having a plurality of nodes, the awakenable system comprising:

(a) a device configurable to operate in a sleep mode;

(b) a memory coupled to said device; and

(c) a controller for coupling to said network by way of the uniquely addressable node and thereby receiving information packets from the network, where said node has a unique physical address and said controller includes;

(c.1) detecting circuitry operative to detect a wake-up data sequence within an information packet received by the controller from said network, said information packet containing an address portion and a data portion, where the wake-up data sequence is constituted at least by said unique physical address repeated N consecutive times within said data portion of said information packet, where N is an integer greater than one; and

(c.2) control circuitry, coupled to said detecting circuitry, for generating a wake-up control signal to awaken said device in response to said detecting circuitry detecting the wake-up data sequence.

2. The system of claim 1, wherein said detecting circuitry includes a counter operatively coupled to count how many times said unique physical address repeats consecutively within said data portion.

3. The system of claim 1, wherein said control circuitry comprises acknowledgment circuitry operative to maintain said wake-up control signal until assertion of the wake-up control signal is acknowledged by another circuit.

4. The system of claim 1, wherein said address portion of said information packet comprises a destination address portion and a source address portion.

5. The method of claim 1, wherein said device is powered by a battery.

6. The system of claim 1, wherein the value of N equals at least 16.

7. The method of claim 1, wherein said information packet further includes a length portion and an error correction portion.

8. In a communications system having a plurality of interlinked, uniquely-addressed nodes, wherein at least one of said nodes includes an awakenable device configured to operate in a sleep mode, a method for waking such an awakenable device from the sleep mode, said waking method comprising the steps of:

(a) receiving at a given node having such an awakenable device, an information packet sent over said communications system, said information packet containing an address field and a data field;

(b) determining at the given node whether an address sequence corresponding to a unique address of the given node occurs at least N consecutive times within said data field of said received information packet, where N is an integer greater than one; and

(c) generating a control signal to wake said device of the given node in response to said determining step finding said N consecutive occurrences of said address sequence.

9. The method of claim 8 wherein step (b) of determining comprises the step of:

(b1) incrementing a counter for each consecutive occurrence of said address sequence in said data field of said information packet.

10. The method of claim 8, wherein N equals at least 16.

11. The method of claim 8, wherein said awakenable device is powered by a battery.

12. The method of claim 8, wherein said corresponding address sequence includes the unique physical address of said at least one node that contains the awakenable device.

13. The method of claim 8, further including the step of;

(d) after the awakenable device is awakened, processing further information contained within received information packets.

14. The method of claim 8, wherein if said address sequence does not occur at least N consecutive times, said awakenable device is not awakened.

15. An integrated circuit for switching an asleep node of a network to an awakened state, said integrated circuit comprising:

a controller coupled to access frame data received by said node, and to further access a unique physical address of said node, where the node has circuitry disposed therein to monitor said network for information packets addressed to said node while the node is in the asleep mode, said information packets including a destination address area and a frame data area;

said controller including detection circuitry for detecting within the accessed frame data, consecutively repeated occurrences of a subsequence corresponding to the unique physical address of said node;

wherein upon detecting the occurrence of said subsequence repeated at least 16 consecutive times within the accessed frame data, said controller generates a wake-up signal for initiating the switching of said node to the awakened state.

16. The integrated circuit of claim 15, wherein said detection circuitry includes a counter for counting the number of consecutively repeated occurrences of said subsequence.

17. The integrated circuit of claim 15, wherein said node includes a device that switches from a power-conserving mode to a higher-power mode in response to said controller generating the wake-up signal.

18. A system comprising a network having a plurality of nodes including an awakenable node that can be placed into a sleep mode, wherein the awakenable node has a unique physical address and comprises:

a switchable device that can be switched between a low power mode and a comparably higher power mode;

network interface means for receiving information packets transmitted over said network, said information packets having an address field and a frame data field;

power management circuitry for switching said device from the low power mode to the higher power mode in response to a wake-up signal; and

a controller including control circuitry responsive to frame data provided in received ones of said information packets, said controller generating said wake-up signal in response to receipt of an information packet containing a wake-up command, said wake-up command including at least 16 consecutive repetitions of a subsequence corresponding to said unique physical address of said awakenable node within said frame data field of said information packet.

19. The system of claim 18, wherein said control circuitry comprises a counter for counting the number of consecutively repeated occurrences of said subsequence.

20. The system of claim 18, wherein the address field of said information packet comprises a destination address field and a source address field.

21. The system of claim 18, wherein said information packets further include a length field and an error checking field.

22. The system of claim 18, wherein said switchable device is powered by a battery.

23. The system of claim 18, wherein said switchable device is contained within a portable computer.

24. A system for allowing awakening of a sleeping portion of an addressable first node belonging to a network of uniquely addressable nodes, wherein said addressable first node of the system has a unique address and comprises:

a packet receiver capable of receiving information packets transmitted over the network from other nodes, each packet including a destination address field and a data field;

a sequence recognizer coupled to the packet receiver, for recognizing the presence within the data field of each received packet, of a consecutive repetition of an address subsequence corresponding to the unique address of the first node; and

an awakening mechanism, responsively coupled to the sequence recognizer, for initiating awakening of the sleeping portion of the addressable first node in response to the sequence recognizer recognizing the presence within the data field of the received information packets, of the consecutive repetition of the address subsequence.

25. The system of claim 24, wherein the unique address of the first node is a physical address of the first node.

26. The system of claim 24, wherein the sleeping portion of the addressable first node is powered by a battery.

27. The system of claim 24, wherein the sleeping portion of the addressable first node is at least partially contained within a portable computer.

28. In a data exchange system having a plurality of individual nodes coupled to one another through a transmission medium, wherein at least one of the nodes is a switchable node that includes a corresponding device which can be placed in a first mode of operation and thereafter switched to a second mode of operation, a method of remotely switching the device from the first mode of operation to the second mode of operation, said remote switching method comprising the steps of:

(a) receiving at a given, switchable node, one or more information packets each having a frame data block containing sequential data, where the sequential data has been transferred through said transmission medium, and where the received one or more information packets each includes a destination field containing a destination address referencing the switchable node;

(b) recovering the sequential data contained in the received one or more information packets;

(c) determining if the device is in said first mode of operation;

(d) determining whether a unique subsequence repeats at least N consecutive times within said recovered sequential data, where N is an integer greater than one, and where the unique subsequence corresponds to the node-referencing destination address; and

(e) initiating a switching of said device to the second mode of operation in response to a finding by said determining steps that the device is in said first mode of operation and there are N consecutive repetitions of said unique subsequence in said recovered sequential data.

29. A remote switching method according to claim 28 wherein said device consumes a first amount of power when in the first mode of operation and said device consumes a greater, second amount of power when in the second mode of operation.

30. A remote switching method according to claim 28 wherein said corresponding device includes at least one of a central processing unit (CPU), a memory unit, and a disk unit where said at least one unit is placed in a power-conserving mode when said corresponding device is placed in the first mode of operation and said at least one unit is placed in a higher power mode when said device is switched to the second mode of operation.

31. In a data exchange system having a plurality of individual nodes coupled to one another through a transmission medium, wherein at least one of the nodes is a switchable node that includes a corresponding device which can be placed in a first mode of operation and thereafter switched to a second mode of operation, a method of remotely switching the device from the first mode of operation to the second mode of operation, said remote switching method comprising the steps of:

(a) forming in a source node, a command packet having a destination field that contains a destination address referencing a switchable node, where the formed command packet further has a frame data block containing N consecutive repetitions of a unique subsequence, where the unique subsequence corresponds to the destination address of the switchable node; and

(b) transmitting the command packet by way of said transmission medium.

32. A remote switching method according to claim 31 wherein said device of the switchable node referenced by the destination field consumes a first amount of power when in the first mode of operation and said device consumes a greater, second amount of power when in the second mode of operation.

33. A mode controlling mechanism for use in switchable node of a data exchange system having a plurality of individual nodes coupled to one another through a transmission medium, wherein the switchable node includes a corresponding device which can be placed in a first mode of operation and thereafter switched to a second mode of operation, said mode controlling mechanism comprising:

(a) a receiver for receiving at said switchable node, one or more information packets each having a frame data block containing sequential data, where the sequential data has been transferred through said transmission medium, and where the received one or more information packets each includes a destination field containing a destination address referencing the switchable node;

(b) a frame data extractor for recovering the sequential data contained in the received one or more information packets;

(c) a mode determiner for determining if the device is in said first mode of operation;

(d) a sequence detector for determining whether a unique subsequence repeats at least N consecutive times within said recovered sequential data, where N is an integer greater than 1, and where the unique subsequence corresponds to the node-referencing destination address; and

(e) an initiator for initiating a switching of said device to the second mode of operation in response to a finding by said mode determiner that the device is in said first mode of operation and in response to a finding by said sequence detector that there are N consecutive repetitions of said unique subsequence in said recovered sequential data.

34. A mode controlling mechanism according to claim 33 wherein said initiator includes a flip flop that sets in response to a finding by said sequence detector that there are N consecutive repetitions of said unique subsequence and resets in response to a finding by said mode determiner that the device is not in said first mode of operation.

35. A mode controlling mechanism according to claim 33 wherein said sequence detector includes a sequence counter that resets upon detection of a mismatch with said N consecutive repetitions of said unique subsequence in said recovered sequential data.

36. A mode controlling mechanism according to claim 33 wherein N is at least 16.

37. A mode controlling mechanism according to claim 36 wherein at least the sequence detector and initiator are contained within an integrated circuit.

38. A mode controlling mechanism according to claim 37 wherein the sequence detector includes a comparator, a subsequence-storing memory unit coupled to supply the subsequence to the comparator, and an address sequence coupled to the subsequence-storing memory unit for sequencing through data stored in the subsequence-storing memory unit.

39. A mode controlling mechanism according to claim 38 wherein said comparator, subsequence-storing memory unit, and address sequencer are further used to determine whether the received one or more information packets each includes a destination field containing a destination address referencing the switchable node.