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:
Jan. 13, 2015
Filed:
Sep. 03, 2004
Jae-sun Cha, Cheongju, KR;
Sung-cheol Chang, Daejeon, KR;
Jae-Sun Cha, Cheongju, KR;
Sung-Cheol Chang, Daejeon, KR;
Electronics and Telecommunications Research Institute, , KR;
Samsung Electronics Co., Ltd, , KR;
KT Corporation, , KR;
SK Telecom Co., Ltd, , KR;
KTFreetel Co., Ltd, , KR;
Hanaro Telecom., Inc., , KR;
Abstract
Disclosed is a handover method in a wireless portable Internet system. When a mobile subscriber station is in a drop state, a ranging request message including an identifier of a previous base station and a string generated by encoding the ranging request message using an authentication key of the previous base station is sent to a target base station. The target base station requests the previous base station to execute handover of the mobile subscriber station using the identifier of the previous base station included in the ranging request message. The previous base station carries out message authentication using the encoded string received from the target base station, and when the authentication is successful, transmits information about the mobile subscriber station that is required for handover to the target base station. Accordingly, a ceaseless service session can be provided even in the drop state.