Patent US4732737A successfully refreshed from Google Patents.
Patent US5404350A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5404350A Expired / Lapsed US ⏱️ 0.0 years remaining

Routing calls destined for inaccessible destinations

Assignee: General Electric Co
•
Filing: 1993-11-05
•
Granted: 1995-04-04
•
Expires: 2013-11-05
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An arrangement for selectively routing traffic to alternate destinations. If the network or switch for accessing the primary destination is inaccessible (i.e., out of service), as opposed to simply being busy, calls are routed to an alternate destination; however, if the primary destination is simply busy, calls are not routed to any alternate destination. This is useful, for example, for emergency (E911) calls which are routed to alternate emergency bureaus only if the network or switch for accessing the home bureau is out of service. Alternatively, the tandem switch can select an alternate toll carrier on the basis of allocation of traffic to different alternate toll carriers. The same general kind of arrangement can be used to route calls to an alternate toll carrier if the preferred toll carrier selected by the customer is not accessible.

Inventors

  • 👤 Nicholas M. DeVito
  • 👤 William E. Hagerman
  • 👤 Ted Moulos

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 19:38
CPC Classifications
H; H04; H04M; H04M3/00; H04M3/42; H04M3/50; H04M3/51; H04M3/523; H04M3/5237; H04Q; H04Q3/00; H04Q3/0016; H04M2207/00; H04M2207/12; H04M3/5116

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 227 words
In a telecommunications network a method of routing a call to an alternative destination, said method comprising the steps of: receiving said call in said telecommunications network; if a primary circuit switching system for serving a primary destination becomes inaccessible, receiving in a circuit switching system for routing said call, or in a routing data base for providing data for routing said call to said circuit switching system for routing said call, an indication from said network of primary circuit switching system inaccessibility; subsequently, responsive to receipt of a request to route said call to said primary destination, testing, in said circuit switching system for routing said call, or in said routing data base, whether said primary circuit switching system is accessible; if said primary circuit switching system is accessible, attempting to route said call only to said primary circuit switching system; and if said primary circuit switching system is not accessible, attempting to route said call to an alternate circuit switching system for serving an alternate destination, said alternate circuit switching system different from said primary circuit switching system; wherein said network comprises at least one Signal Transfer Point, STP, and wherein said receiving an indication comprises: receiving a message from an STP for signaling to said primary circuit switching system indicating that said at least one STP cannot communicate with said primary circuit switching system.
Claim 2
Dependent Claim 227 words
In a telecommunications network a method of routing a call to an alternative destination, said method comprising the steps of: receiving said call in said telecommunications network; if a primary circuit switching system for serving a primary destination becomes inaccessible, receiving in a circuit switching system for routing said call, or in a routing data base for providing data for routing said call to said circuit switching system for routing said call, an indication from said network of primary circuit switching system inaccessibility; subsequently, responsive to receipt of a request to route said call to said primary destination, testing, in said circuit switching system for routing said call, or in said routing data base, whether said primary circuit switching system is accessible; if said primary circuit switching system is accessible, attempting to route said call only to said primary circuit switching system; and if said primary circuit switching system is not accessible, attempting to route said call to an alternate circuit switching system for serving an alternate destination, said alternate circuit switching system different from said primary circuit switching system; wherein said network comprises at least one Signal Transfer Point, STP, and wherein said receiving an indication comprises: receiving a message from an STP for signaling to said primary circuit switching system indicating that said at least one STP cannot communicate with said primary circuit switching system.
Claim 3
Dependent Claim 23 words
The method of claim 1 wherein said step of receiving a message comprises the step of receiving at least one transfer prohibit message.
Claim 4
Dependent Claim 225 words
In a telecommunications network a method of routing a call to an alternative destination, said method comprising the steps of: receiving said call in said telecommunications network; if a primary circuit switching system for serving a primary destination becomes inaccessible, receiving in a circuit switching system for routing said call, or in a routing data base for providing data for routing said call to said circuit switching system for routing said call, an indication from said network of primary circuit switching system inaccessibility; subsequently, responsive to receipt of a request to route said call to said primary destination, testing, in said circuit switching system for routing said call, or in said routing data base, whether said primary circuit switching system is accessible; if said primary circuit switching system is accessible, attempting to route said call only to said primary circuit switching system; and if said primary circuit switching system is not accessible, attempting to route said call to an alternate circuit switching system for serving an alternate destination, said alternate circuit switching system different from said primary circuit switching system further comprising: responsive to receiving said call, said circuit switching system for routing said call requests routing data for said call from said routing data base; and wherein said circuit switching system for routing said call receives said routing data from said routing data base.
Claim 5
Dependent Claim 225 words
In a telecommunications network a method of routing a call to an alternative destination, said method comprising the steps of: receiving said call in said telecommunications network; if a primary circuit switching system for serving a primary destination becomes inaccessible, receiving in a circuit switching system for routing said call, or in a routing data base for providing data for routing said call to said circuit switching system for routing said call, an indication from said network of primary circuit switching system inaccessibility; subsequently, responsive to receipt of a request to route said call to said primary destination, testing, in said circuit switching system for routing said call, or in said routing data base, whether said primary circuit switching system is accessible; if said primary circuit switching system is accessible, attempting to route said call only to said primary circuit switching system; and if said primary circuit switching system is not accessible, attempting to route said call to an alternate circuit switching system for serving an alternate destination, said alternate circuit switching system different from said primary circuit switching system further comprising: responsive to receiving said call, said circuit switching system for routing said call requests routing data for said call from said routing data base; and wherein said circuit switching system for routing said call receives said routing data from said routing data base.
Claim 6
Dependent Claim 228 words
In a telecommunications network, comprising a plurality of toll carrier networks each comprising ingress circuit switching systems for receiving calls from a local carrier and egress circuit switching systems for transmitting calls to a local carrier, a method of routing a toll call to a toll carrier network, said method comprising the steps of: if an ingress circuit switching system for a toll carrier network becomes inaccessible, receiving in said telecommunications network an indication of toll carrier ingress circuit switching system inaccessibility for said toll carrier network; receiving said toll call in said telecommunications network; determining a preferred toll carrier network of said plurality of toll carrier networks for said toll call; testing whether a toll carrier network ingress circuit switching system is accessible for said preferred toll carrier network; if the toll carrier network ingress circuit switching system for said preferred toll carrier network is accessible, attempting to route said toll call only via said preferred toll carrier network; and if said preferred toll carrier ingress circuit switching system is not accessible, attempting to route said call via an alternate toll carrier network accessed via an ingress circuit switching system of said alternate toll carrier network; wherein prior to attempting to route said call via said alternate toll carrier network an announcement is made to a caller of said call indicating a change of toll carrier network.
Claim 7
Dependent Claim 228 words
In a telecommunications network, comprising a plurality of toll carrier networks each comprising ingress circuit switching systems for receiving calls from a local carrier and egress circuit switching systems for transmitting calls to a local carrier, a method of routing a toll call to a toll carrier network, said method comprising the steps of: if an ingress circuit switching system for a toll carrier network becomes inaccessible, receiving in said telecommunications network an indication of toll carrier ingress circuit switching system inaccessibility for said toll carrier network; receiving said toll call in said telecommunications network; determining a preferred toll carrier network of said plurality of toll carrier networks for said toll call; testing whether a toll carrier network ingress circuit switching system is accessible for said preferred toll carrier network; if the toll carrier network ingress circuit switching system for said preferred toll carrier network is accessible, attempting to route said toll call only via said preferred toll carrier network; and if said preferred toll carrier ingress circuit switching system is not accessible, attempting to route said call via an alternate toll carrier network accessed via an ingress circuit switching system of said alternate toll carrier network; wherein prior to attempting to route said call via said alternate toll carrier network an announcement is made to a caller of said call indicating a change of toll carrier network.

References Cited (Backward Citations)

US3278692A Cited
US5049873A Cited
US5212475A Cited
US4943999A Cited
US4979164A Cited
US5016243A Cited
US5239570A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-04-03 1998-10-03 1999-04-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-04-03 2002-10-03 2003-04-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-04-03 2006-10-03 2007-04-04 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag