Signaling mechanism for modem connection holding and reconnecting

• US 20040086097A1
• Filed: 06/25/2003
• Published: 05/06/2004
• Est. Priority Date: 04/12/1999
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Conexant Systems Incorporated (Synaptics Incorporated)
• Inventors: Olafsson, Sverrir
• Granted Patent: US 6,842,509 B2
• Time in Patent Office: Days
• US Class Current: 379/93.32
• 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 11/06 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
• CPC Class Codes: H04M 3/428 Arrangements for placing incoming calls on hold

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 signaling method for changing operating modes in a data communication system having a first device configured to communicate with a second device via a communication link, said method comprising the steps of:

transmitting a modem status signal from said first device to said second device, said modem status signal being configured as a differential phase-shift keying (DPSK) signal based on a predetermined bit pattern;

detecting said modem status signal at said second device; and

initiating a procedure associated with a change in the operating mode of said data communication system in response to said modem status signal.

2. A signaling method according to claim 1, wherein said modem status signal represents a modem hold request.

3. A signaling method according to claim 1, wherein said modem status signal represents a modem hold acknowledgment.

4. A signaling method according to claim 1, wherein said modem status signal represents a quick reconnect request.

5. A signaling method according to claim 1, wherein said modem status signal represents a disconnect signal.

6. A signaling method according to claim 1, wherein said modem status signal is configured as a DPSK signal based on a repetitive sequence of a predetermined bit pattern.

7. A signaling method according to claim 6, wherein said modem status signal is configured as a DPSK signal based on eight repetitions of a four-bit pattern.

8. A signaling method according to claim 7, wherein said four-bit pattern is one of the following patterns:

0101, 0011, 0001, or 0111.

9. A signaling method for changing operating modes in a data communication system having a first device configured to communicate with a second device via a communication link, said method comprising the steps of:

receiving a modem status signal in response to a change in the operating mode of said data communication system;

detecting said modem status signal by analyzing a number of spectral components associated with said modem status signal; and

initiating a procedure associated with said change in the operating mode of said data communication system in response to said modem status signal.

10. A signaling method according to claim 9, wherein:

said modem status signal is configured as a differential phase-shift keying (DPSK) signal based on a predetermined bit pattern; and

said detecting step is performed by a tone detector.

11. A signaling method according to claim 9, wherein:

said modem status signal is configured as a differential phase-shift keying (DPSK) signal based on a predetermined bit pattern; and

said detecting step is performed by a DPSK receiver.

12. A signaling method according to claim 9, further comprising the step of receiving an A-tone prior to receiving said modem status signal.

13. A signaling method according to claim 13, wherein said A-tone is a 2400 Hz tone.

14. A signaling method for changing operating modes in a data communication system having a first device, resident at a client site, configured to communicate with a second device via a communication link, said method comprising the steps of:

receiving, at said first device, an indication related to the termination of an incoming call directed to said client site;

transmitting a modem status signal from said first device to said second device, said transmitting step being performed in response to said receiving step;

detecting said modem status signal with said second device; and

initiating, in response to said detecting step, a quick reconnect procedure to recall a stored operating parameter for said data communication system, said stored operating parameter being associated with a previous communication session between said first and second devices.

15. A data communication device comprising:

a receiver configured to receive a first indication related to an interruption in a current data mode;

a transmitter configured to transmit a first modem status signal to a remote data communication device in response to said indication, said first modem status signal being formatted as a differential phase-shift keying (DPSK) signal based on a first predetermined bit pattern;

wherein

said receiver is further configured to receive a second modem status signal indicative of a modem hold mode, said second modem status signal being formatted as a DPSK signal based on a second predetermined bit pattern.

16. A data communication device according to claim 15, wherein:

said receiver is further configured to receive a second indication related to the termination of an incoming call;

said transmitter is further configured to transmit a third modem status signal to said remote data communication device in response to said second indication, said third modem status signal being formatted as a DPSK signal based on a third predetermined bit pattern; and

said third modem status signal is formatted to initiate a reconnect procedure to recall a stored operating parameter for said data communication system, said stored operating parameter being associated with a previous communication session conducted by said data communication device.