Electronics and Telecommunications Research Institute

Samsung Electronics Co., Ltd.

Kt Corporation

Sk Telecom Company, Ltd.

Hanaro Telecom., Inc.

Ktfreetel Co., Ltd

Sung-Cheol Chang

Chul-Sik Yoon

Seok-Heon Cho

Kyung-Soo Kim

Byung-Jae Kwak

Dong-Seung Kwon

Eun-Kyung Kim

Sook-Jin Lee

Ju-Hee Kim

Jae-Su Song

Jae-Sun Cha

Dong-Hyun Ahn

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.

Handover method in wireless portable internet system

A method and authentication apparatus for sharing information for identifying an Authorization Key (AK) with a Base Station (BS) in a subscriber station are provided. The method includes, in the subscriber station, sharing a root key with the BS by performing an authentication with the BS, sharing an AK derived from the root key with the BS, sharing an AK sequence number of the AK with the BS, and sharing an AK Identifier (AKID) of the AK with the BS. The AK sequence number is generated by a sequence number of the root key. The AKID is generated by a parameter including the AK, the AK sequence number, a Medium Access Control (MAC) address of the subscriber station, and a BS Identifier (BSID) of the BS.

Method for allocating authorization key identifier for wireless portable internet system

When an event associated with a mobile station occurs, a relay station requests a base station to allocate a dedicated control channel required for transmitting control information on the mobile station to the base station. Next, when the control information on the mobile station is generated, the relay station transmits the control information to the base station through the dedicated control channel. Accordingly, since the base station allocates the dedicated control channel to the relay station in advance before the control information is generated in the relay station, the relay station can transmit the control information to the base station with a minimum of time delay.

Apparatus and method for relaying between base station and mobile station, and method for receiving control information

The present invention relates to a method for allocating an authorization key identifier in a wireless portable Internet system. In a privacy key management version 2 (PKMv2) of the wireless portable Internet system, a base station generates PAK identifier, PMK identifier, and authorization key identifier for distinguishing a primary authorization key (PAK) shared by the base station and the subscriber station in an RSA-based authorization, a pairwise master key (PMK) shared by the base station and the subscriber station in an EAP-based authorization, and authorization keys generated by the PAK and the PMK. The base station transmits PAK identifier, PMK identifier, and authorization key identifier to the subscriber station and shares them with the subscriber station. Therefore, the base station and the subscriber station may easily distinguish more than 2 authorization-related keys. In addition, it is possible to transmit the signal message efficiently in the radio channel by reducing the sizes of the PAK identifier, PMK identifier, and authorization key identifier.

Disclosed is a traffic encryption key (TEK) management method for automatically generating a TEK for a multicast or broadcast service by a base station to periodically update a TEK used by a subscriber station. The base station transmits the first Key Update Command message for updating a group key encryption key (GKEK) for encrypting the TEK and the second Key Update Command message for updating the TEK to the subscriber station to update the TEK. The base station establishes an M & B TEK Grace Time which is different from a TEK Grace Time established by the subscriber station, transmits the first message including a new GKEK to the subscriber station through a primary management connection before the M & B TEK Grace Time, and transmits the second message including a new TEK encrypted with the new GKEK thereto through a broadcast connection after the M & B TEK Grace Time.

Method for managing traffic encryption key in wireless portable internet system and protocol configuration method thereof, and operation method of traffic encryption key state machine in subscriber station

The present invention relates to a method for searching and releasing an abnormal subscriber station in a wireless portable Internet system, and an apparatus using the same. The apparatus searches for an abnormal group including abnormal subscriber stations based on a ranging code provided in a periodic ranging process, and searches for an abnormal subscriber station by transmitting a connection maintenance message to subscriber stations included in the abnormal group so as to check an operation status of the respective subscriber stations. In addition, the apparatus releases a connection of an abnormal subscriber station. Therefore, waste of radio resources allocated to the abnormal subscriber station can be prevented, thereby achieving efficient resource management. Further, a secondary search process is performed only for subscriber stations included in an abnormal group, thereby preventing a system load from occurring when searching for an abnormal subscriber station.

Method and device for searching and deallocating abnormal terminal in wireless portable internet system

Disclosed is a handover method in a next-generation mobile communication system. When a terminal is in the idle state, an IP is reallocated according to a process of mobile IPs to perform a location registration process, and when the terminal is in the active state, it operates according to a procedure of a mobile communication network. Therefore, the terminal operates in two modes to support mobility on the IP-based networks, and it performs a handover procedure by configuring a layer below the MAC to a new AS without allocating the IP at the handover state when it is in the active state to thus minimize handover delay time.

Growing community of inventors

Daejeon, South Korea

Sung-Cheol Chang