Patent · US Expired

Emergency service call back to a ported number

US7480374B2 · kind B2 · utility

3Cited by
8References
23Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 16, 2003
Grant dateJan 20, 2009
Priority date
Expiry dateDec 17, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M2242/04
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

An emergency routing number (ELRN) is assigned to each switch in a wired communication network. When a switch of the wired communication network routes an emergency call to a Public Service Answering Point (PSAP), the switch sends the ELRN as the calling party number and provides the PSAP with a hardware identifier (HID). The HID identifies, at the switch, the landline connecting the switch to the wired phone initiating the emergency call. If the emergency call drops, the PSAP performs a call back using the ELRN as the called party number. The switch that routed the emergency call to the PSAP receives the call back. The PSAP also sends the HID to the switch. When a switch receives its ELRN as the called party number, the switch recognizes an emergency call back situation and routes the emergency call back on the landline identified by the HID.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.