The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 12, 2021
Filed:
May. 17, 2019
Telefonaktiebolaget Lm Ericsson (Publ), Stockholm, SE;
Fredrik Lindholm, Tokyo, JP;
Ralf Keller, Würselen, DE;
Susana Fernandez Alonso, Madrid, ES;
Ivo Sedlacek, Hovorcovice, CZ;
TELEFONAKTIEBOLAGET LM ERICSSON (PUBL), Stockholm, SE;
Abstract
A method in a proxy call session control function, P-CSCF, of handling an unauthenticated emergency call originating from a roaming user equipment that is not attached to the P-CSCF. The P-CSCF receives a session initiation protocol (SIP) REGISTER request from the UE, where the REGISTER request relating to the emergency registration. The P-CSCF determines an IP address of the UE. The P-CSCF sends an identity query to a policy and charging rules function (PCRF) indicating the IP address of the UE and requesting other identifiers of the UE. The P-CSCF receives one or more other identifiers of the UE from the PCRF. The P-CSCF obtains a TEL and/or SIP uniform resource identifier (URI) for the UE on the basis of at least one of the one or more other identifiers. The P-CSCF sends a 200 OK response to the UE in response to the SIP REGISTER request, where the 200 OK response includes the TEL and/or SIP URI. Also provided are corresponding methods in other nodes and for authenticated emergency calls, and apparatus for implementing the methods.