Method and apparatus for quick modem reconnect

• US 20040096044A1
• Filed: 07/02/2003
• Published: 05/20/2004
• Est. Priority Date: 04/12/1999
• Status: Active Grant

• Current Assignee: Silicon Laboratories Incorporated
• Original Assignee: Silicon Laboratories Incorporated
• Inventors: Olafsson, Sverrir, Beadle, Burk
• Granted Patent: US 7,027,573 B2
• Time in Patent Office: Days
• US Class Current: 379/93.32
• CPC Class Codes: H04L 25/4902 Pulse width modulation; Pulse position modulation
• CPC Class Codes: H04L 27/02 Amplitude-modulated carrier systems, e.g. using on-off keying; Single sideband or vestigial sideband modulation H04L27/32 takes precedence
• CPC Class Codes: H04L 5/1438 Negotiation of transmission parameters prior to communication modified according to link quality H04L1/0001
• CPC Class Codes: H04L 69/24 Negotiation of communication capabilities
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04M 11/00 Telephonic communication systems specially adapted for combination with other electrical systems
• CPC Class Codes: H04M 11/06 Simultaneous speech and data transmission, e.g. telegraphic transmission over the same conductors
• CPC Class Codes: H04M 11/066 Telephone sets adapted for data transmision

Abstract

A quick startup procedure for a modem system utilizes known characteristics of a previously established communication channel to reduce the initialization period associated with subsequent connections over the same channel. In response to the establishment of a call, the modem devices determine whether the quick connect protocol is supported. If so, then the called modem transmits a modified answer tone to the calling modem. The calling modem analyzes the signal received in response to the modified answer tone to determine whether characteristics of the current channel are similar to stored characteristics associated with a previous connection over the same channel. If a channel “match” is found, then the modem devices carry out a quick initialization routine that eliminates, abbreviates, or modifies a number of procedures or protocols that are carried out in conventional modem startup processes. The general quick startup techniques may also be applied in the context of a quick reconnect procedure that can be performed in response to a temporary pausing or disconnecting of the data modem mode.

Claims

1. A method of reducing time for reconnecting a first device to a second device via a communication link, said method comprising the steps of:

establishing a communication session between said first device and said second device over a communication channel;

obtai ning an operating parameter for said data transmission system, said operating parameter being associated with said communication channel;

storing said operating parameter at said second device as a stored operating parameter; and

recalling said stored operating parameter, in response to the termination of a temporary pause in said communication session, to thereby obtain a recalled operating parameter.

2. A method according to claim 1, wherein said obtaining step comprises the step of initializing at least one of said first and second devices.

3. A method according to claim 1, further comprising the steps of:

resetting said second device utilizing said recalled operating parameter; and

subsequently re-establishing a data transmission mode between said first and second devices.

4. A method according to claim 1, further comprising the steps of:

receiving a reconnect indication at said first device, said reconnect indication being generated in response to a request to terminate said temporary pause in said communication session;

transmitting a signal point sequence from said first device to said second device in response to said reconnect indication;

acquiring a received sequence at said second device, said received sequence being related to said signal point sequence; and

determining characteristics of said data communication network in response to said received sequence.

5. A method according to claim 4, wherein said determining step determines characteristics of digital impairments associated with said data communication network.

6. A method according to claim 4, wherein said signal point sequence comprises a sequence of pulse code modulation signal points.

7. A method according to claim 1, wherein:

said obtaining step further obtains a second operating parameter for said data transmission system, said second operating parameter being associated with said communication channel;

said storing step further stores said second operating parameter at said first device as a second stored operating parameter; and

said recalling step further recalls said second stored operating parameter, in response to the termination of a temporary pause in said communication session, to thereby obtain a second recalled operating parameter.

8. A method according to claim 1, wherein said stored operating parameter comprises initialization data associated with a receiver resident at said second device.

9. A method of reducing time for reconnecting a first device to a second device via a communication link, each of said first and second devices being configured to maintain a number of stored operating parameters associated with a data transmission mode, said method comprising the steps of:

receiving a reconnect indication at said first device;

transmitting a reply signal from said first device to said second device in response to said reconnect indication;

recalling a stored operating parameter at said second device in response to said reply signal to thereby obtain a recalled operating parameter for said second device; and

subsequently re-establishing said data transmission mode between said first and second devices using said recalled operating parameter for said second device.

10. A method according to claim 9, further comprising the step of resetting said second device utilizing said recalled operating parameter for said second device.

11. A method according to claim 9, wherein:

said recalling step further recalls a stored operating parameter at said first device in response to said reconnect indication to thereby obtain a recalled operating parameter for said first device; and

said re-establishing step further re-establishes said data transmission mode between said first and second devices using said recalled operating parameter for said first device.

12. A method according to claim 9, wherein said reply signal comprises a signal point sequence configured to enable said second device to determine characteristics of digital impairments associated with said data communication network.

13. A method according to claim 12, wherein said signal point sequence comprises a sequence of pulse code modulation signal points.

14. A method according to claim 9, wherein said reply signal comprises a transition sequence configured to enable said second device to determine robbed bit signaling characteristics of said data communication network.

15. A method according to claim 14, wherein said transition sequence comprises positive and negative values of at least one signal point.

16. A method according to claim 9, wherein said stored operating parameter comprises data associated with impairments of said communication link.

17. A method according to claim 9, wherein said stored operating parameter comprises data associated with a signal point constellation for said second device.

18. A method according to claim 9, wherein said stored operating parameter comprises data associated with echo canceler settings for said second device.

19. A method according to claim 9, wherein said stored operating parameter comprises data associated with power level settings for said second device.

20. A data transmission system comprising a first device and a second device configured to communicate with each other over a communication channel via a data communication network, said first device comprising:

a memory element configured to maintain a first number of stored operating parameters associated with a data transmission mode of said data transmission system;

a receiver section configured to receive communication signals transmitted by said second device and to receive a reply signal in response to a request to terminate a temporary pause in said data transmission mode; and

a processor element configured to recall at least one of said first number of stored operating parameters at said first device in response to said reply signal to thereby obtain at least one recalled operating parameter for said first device, and to reset said first device utilizing said at least one recalled operating parameter for said first device.

21. A data transmission system according to claim 20, wherein said second device comprises:

a second memory element configured to maintain a second number of stored operating parameters associated with said data transmission mode;

a second receiver section configured to receive communication signals transmitted by said first device and to receive a reconnect indication, said reconnect indication being generated in response to said request; and

a second processor element configured to recall at least one of said second number of stored operating parameters at said second device in response to said reconnect indication to thereby obtain at least one recalled operating parameter for said second device, and to reset said second device utilizing said at least one recalled operating parameter for said second device.

22. A data transmission system according to claim 21, wherein said second device further comprises a second transmitter section configured to transmit communication signals to said first device and to transmit said reply signal.

23. A data transmission system according to claim 20, wherein said reply signal comprises a transition sequence configured to enable said second device to determine robbed bit signaling characteristics of said data communication network.

24. A data transmission system according to claim 20, wherein said reply signal comprises a signal point sequence configured to enable said first device to determine characteristics of digital impairments associated with said data communication network.

25. A data transmission system according to claim 20, wherein at least one of said first and second devices is compatible with ITU-T Recommendation V.90.

26. A data transmission device comprising:

a memory element configured to maintain a stored operating parameter associated with a data transmission mode of said data transmission device;

a receiver section configured to receive communication signals transmitted by a remote device and to receive a reply signal in response to a reconnect request; and

a processor element configured to recall said stored operating parameter in response to said reply signal to thereby obtain a recalled operating parameter, and to reset said data transmission device utilizing said recalled operating parameter.

27. A data transmission device according to claim 26, wherein said reply signal is associated with a request to terminate a temporary pause in said data transmission mode.

28. A data transmission device according to claim 26, wherein said recalled operating parameter is used to re-establish said data transmission mode.

29. A data transmission device according to claim 26, wherein said stored operating parameter comprises initialization data associated with a receiver resident at said data transmission device.

30. A data transmission device according to claim 26, wherein said data transmission device is further configured such that it is compatible with ITU-T Recommendation V.90.