Patent · US Expired

Closed user group preprocessing decision for efficient call security validation

US5987520A · kind A · utility

19Cited by
6References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 16, 1998
Grant dateNov 16, 1999
Priority date
Expiry dateJan 16, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M3/382
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A network node preprocesses Closed User Group (CUG) member rules and network configuration information available to the node during a configuration phase of the network preceding an operational phase in which calls are placed among the users. The preprocessing stores the information about the CUG membership of network users into a preprocessed CUG information table directly associated with user addresses. CUG membership of some attached users is ambiguous at configuration time if there exists a CUG member rule that is more specific than a prefix configured on the node with which the addresses of such users begin. For such users, CUG membership is determined at call time. The node determines at configuration time whether the CUG membership information concerning users whose addresses begin with each prefix configured on the node is ambiguous, and for those prefixes for which user CUG membership is ambiguous an associated indicator is set. At call time the indicator associated with the user involved in the call is checked. If the indicator is set the node creates CUG membership information about the involved user and uses the created information to authorize the call. If the indicato…

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