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:
Apr. 16, 2002
Filed:
Nov. 13, 1998
Patrick SzeChing Ma, Plano, TX (US);
Nortel Networks Ltd., St. Laurent, CA;
Abstract
An Internet Protocol (IP) telephony system cross-references transport addresses of Gatekeepers using a domain name of the IP telephony system. The IP telephony system is serviced by at least one Gatekeeper and the transport address for each Gatekeeper is stored on a Domain Name Server (DNS). An A record or other suitable record may be employed within the DNS to index the transport addresses of the Gatekeepers to the IP telephony system domain name. A calling endpoint first queries the DNS for the transport address of a Gatekeeper servicing the IP telephony system. The DNS address retrieves at least one transport address for the Gatekeeper(s) and returns the transport address(es) to the calling endpoint. When querying the DNS, the calling endpoint may use an identifier such as subscribername@Gatekeeper.ABC.domain where the user name of the called endpoint is “subscribername” and the domain name of the IP telephony system is ABC.domain.