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:
Jul. 01, 2008
Filed:
Jul. 17, 2003
Tatsuhiko Miyata, Kokubunji, JP;
Kenichi Sakamoto, Kawasaki, JP;
Minoru Hidaka, Kodaira, JP;
Kazuyoshi Hoshino, Komae, JP;
Satoshi Kiyotou, Fujisawa, JP;
Kazuma Yumoto, Hachiouji, JP;
Tatsuhiko Miyata, Kokubunji, JP;
Kenichi Sakamoto, Kawasaki, JP;
Minoru Hidaka, Kodaira, JP;
Kazuyoshi Hoshino, Komae, JP;
Satoshi Kiyotou, Fujisawa, JP;
Kazuma Yumoto, Hachiouji, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
Session Initiation Protocol (SIP), a protocol used in VoIP (Voice over IP) communications, enables a caller to send a SIP message to a callee with his/her UserID concealed from the callee, which in turn, prevents A SIP server from making an attempt to manage the caller. If the same IP Telephone address is used whenever the IP call is made, a third party may guess the IP address easily during conversation. The SIP message sent by the caller is converted and conversion tables are managed by the SIP server. The IP Telephone modifies its IP address for each IP call. Thus, the caller can make a call to the callee with his/her UserID concealed from the callee using the SIP server with a message conversion function and communications carriers having SIP servers installed to manage the callers using their conversion tables. It is difficult to any malicious third party to guess the IP Telephone address, because the IP Telephone address is modified for each call.