Patent EP0487234A2 successfully refreshed from Google Patents.
← Back to Patent Explorer
EP0487234A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Communication system having ISDN signalling capability

Assignee: AT&T Inc
•
Filing: 1991-11-12
•
Granted: —
•
Expires: 2011-11-12
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A communication system operates compatibly with a public or private switching network using a Q.931 protocol for basic rate ISDN communications. Communications between a control unit and station terminals of the system use a local protocol which is a modification of the Q.931 protocol. This local protocol includes one segment including the mandatory elements of the Q.931 protocol and a second segment derived by converting the optional elements of the Q.931 protocol into a local codeset which controls the user interface circuits at each station terminal. The local protocol enables call control between the control unit and each station terminal to be managed on a bearer channel basis while call control between the system and the network is managed on a call appearance basis using the standard Q.931 protocol. The local protocol provides for communicating line selection and feature activation commands from the terminal to the control unit, using simple button commands.

Inventors

  • 👤 Albert D. Baker
  • 👤 Wayne D. Farmer
  • 👤 Richard E. Henderson
  • 👤 Thomas C. Prewitt
  • 👤 Mary Elise Ricker
  • 👤 David Bruce Rucinski
  • 👤 Albert V. Toy
  • 👤 Jerry S. Weltman

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-10-30 21:23
CPC Classifications
H; H04; H04Q; H04Q11/00; H04Q11/04; H04Q11/0428; H04L; H04L9/00; H04L9/40; H04Q11/0435; H04Q11/0457; H04Q2213/00; H04Q2213/216; H04Q2213/22

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 146 words
A communication system arranged to receive information in a Q.931 protocol message over a communication channel, said system including a control unit connected to said channel and connected over a facility to at least one station terminal, said system further including at said control unit means for converting a received Q.931 protocol message into a local protocol message for communicating over said facility with said at least one station terminal, said local protocol message including a first group of information elements containing mandatory Q.931 protocol message information elements and a second group of information elements derived from non-mandatory Q.931 protocol message information elements, for controlling a user-interface device at said at least one station terminal and, at said at least one station terminal means for receiving said local protocol message and for controlling the operation of said user-interface device using said second group of information elements.
Claim 2
Dependent Claim 18 words
The system of claim 1 wherein said local protocol message identifies calls on a bearer channel connection basis.
Claim 3
Dependent Claim 36 words
The system of claim 1 wherein the local protocol message enables said one terminal to manage line selection and feature invocation by sending button identification signals in said local protocol message sent to said control unit.
Claim 4
Dependent Claim 71 words
A station terminal for communicating over a communication facility to a control unit, said terminal comprising means for receiving information from said facility said information being in a local protocol message format having a first group including mandatory elements of a Q.931 protocol format and a second group including a local codeset for controlling a user-interface device of said terminal and means for controlling said user-interface device using said local codeset.
Claim 5
Dependent Claim 19 words
The station terminal of claim 4 wherein said local protocol message identifies calls on a bearer channel connection basis.
Claim 6
Dependent Claim 34 words
The station terminal of claim 4 wherein the local codeset enables said terminal to manage line selection and feature invocation by sending button identification signals in a local protocol message received from said facility.
Claim 7
Dependent Claim 122 words
A control unit for use in a communication system including at least one station terminal connected over a communication facility to said control unit, said control unit comprising means for receiving call control information in a Q.931 protocol format over an external communication channel, means for converting said received Q.931 protocol information into a local protocol message including a first group of information elements containing mandatory Q.931 protocol message information elements, a second group of information elements for controlling a user-interface device at said at least one station terminal, said second group of information elements being derived from non-mandatory Q.931 protocol message information elements and means for sending said local protocol message over said facility to said at least one station terminal.
Claim 8
Dependent Claim 102 words
A communication system arranged to receive Q.931 call control information having a call appearance format over an external communication channel, said system including a control unit connected to said channel and connected over a facility to at least one station terminal, said system further including at said control unit means for converting call control information received in said call appearance format to a local protocol bearer channel format for communicating with said at least one station terminal and at said at least one station terminal means for and controlling call operations thereat using said call control information in said bearer channel format.
Claim 9
Dependent Claim 85 words
A control unit for use in a communication system including at least one station terminal connected over a communication facility to said control unit, said control unit comprising means for communicating, over an external communication channel, call control information having a call appearance format, means for converting said call control information from said call appearance format to a bearer channel format, and means for communicating with said at least one station terminal over said facility using said call control information in said bearer channel format.
Claim 10
Dependent Claim 60 words
A station terminal for communicating over a communication facility to a control unit, said terminal comprising means for communicating with said control unit using a local protocol having bearer channel format elements and user-interface command elements, and means for controlling facility acquisition using said bearer channel format elements and for controlling a user-interface device thereat using said user-interface command elements.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Maintenance schedule is calculated for granted US utility patents.

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag