93 results about "Fast handover" patented technology

A method for performing a handover by a subscriber station (SS) in a broadband wireless communication system including a serving base station (BS) communicating with the SS, and at least one neighbor BS neighboring the serving BS. The SS receives downlink signals from the serving BS and the neighbor BS; measures an arrival time difference between the downlink signal received from the serving BS and the downlink signal received from the neighbor BS; and transmits the measured arrival time difference to the serving BS.

Disclosed is a method for authenticating a mobile node in a wireless local area network including at least two access points and an authentication server. When the mobile node associates with a first access point and performs initial authentication, the mobile node receives a first session key for secure communication from the authentication server by using a first private key generated with a secret previously shared with the authentication server, and the first access point receives the first session key from the authentication server by using a second private key previously shared with the authentication server. When the mobile node is handed over from the first access point to a second access point and performs re-authentication, the mobile node receives a second session key for secure communication from the authentication server by using a third private key generated with authentication information generated during previous authentication and shared with the authentication server and the second access point receives the second session key from the authentication server by using the second private key previously shared with the authentication server.

To achieve a secure and fast handover in a distributed mobile communication environment (10), the control functionality is lying at the borderline between wireless and wire-bound communication network elements, and it is proposed to, firstly, execute a mutual authentication between a mobile device (26) and a new access point (14) using security context information previously transmitted to the new access point. Then, after successful mutual authentication, a handover will be executed from the current access point (12) to the new access point (14).

The invention relates to a SIM-based authentication method capable of supporting inter-AP fast handover, which can decrease the number of authentication procedures without negatively influencing the security of the wireless LAN by establishing an encrypted channel for each mobile node and using method 1: an aggressive key pre-distribution and method 2: probe request triggering passive key pre-query technique, thereby reducing the time of inter-AP handover for the mobile node. Furthermore, a re-authentication procedure is started to update the key after the key is used for a long time so as to ensure that the key is safe, thereby effectively achieving a fast and safe wireless LAN environment.

A fast switching method for TD-LTE communication system based on geographic location information Aiming at the phenomenon of frequent cell switching in high-speed railway TD-LTE communication system, as well as the requirements of short switching time and high switching success rate, a method based on geographic location is proposed. TD-LTE fast switching method of information. According to the train's running position, speed and direction, after the network planning is completed, a list of neighboring cells is generated in advance, and the switching position of each cell switching zone is pre-set, that is, the longitude and latitude position information. When the train enters the overlapping area of ​​the two cells and arrives When the handover position is scheduled, the source base station eNodeB performs handover according to the measurement report of the user terminal UE. The method can dynamically adjust the handover method according to the mobile speed of the user terminal UE, so as to solve the problem of fast handover in a high-speed mobile environment, reduce the number of communication drops, improve the handover success rate, enhance the service quality of high-speed broadband mobile services, and promote The development of multimedia broadband mobile Internet services in high-speed railway trains meets the growing needs of passengers for mobile communication services.

The invention discloses a fast handover protocol flow for heterogeneous wireless networks. The main implementation process of the flow is characterized in that a mobile terminal periodically sends the mobile terminal related information reports to a wireless access network; a network-side wireless access network reconfiguration manager predicts the motion tract of a user; when the mobile terminal needs to initiate handover to maintain the business continuity, the predicted motion information and the network topological information are combined to determine the aggregate of network candidates; a target network for the mobile terminal is selected in advance by the wireless access network reconfiguration manager of the present network and simultaneously the target network is informed to reserve resources required for the mobile terminal; the mobile terminal monitors the received signal intensities of the present network and the target network an determines the optimum handover trigger time; and after triggering handover, the mobile terminal accesses to the target network firstly and then releases the original link resources. The fast handover protocol flow can reduce the handover delay of handover among the heterogeneous wireless networks, increase the success rate of handover and ensure the quality and continuity of business services.

A method of handling a data stream during a handover in a communications network comprising a first user agent having a fixed address, a proxy server and a second user agent, said method comprising the steps of: mapping at the proxy server the fixed address with a dynamic network address allocated to the first user agent; sending a request by the first user agent to the second user agent for a data stream; generating by the second user agent in response to the request a plurality of messages each comprising part of the data stream requested and the fixed address of the first user agent, wherein the message is a session initiation protocol message, and sending the messages to the proxy server; receiving the messages at the proxy server and determining the mapped dynamic network address corresponding to the fixed address in the message, and forwarding the messages to the determined dynamic network address; and when the first user agent is allocated a new dynamic network address, replacing by the proxy server the mapped dynamic network address with the new dynamic network address and forwarding the received messages to the new dynamic network address.

Provided is a mobile IPv6 fast handovers method, which includes the steps of: a) if a mobile node is moved in a layer 2, receiving a modified RS message from a mobile node in the access router, b) detecting movement of the mobile node in a layer 3 in the access router, c) if the mobile node makes a movement in the layer 3, generating CoA of the mobile node in the access router; d) performing Duplicate Address Detection in the access router to inspect uniqueness of the generated CoA; and e) transmitting a modified RA message to the mobile node in the access router. The Fast Handovers method of the present research performs fast movement detection by using layer 2 information simply and efficiently for fast handover in the mobile IPv6 and generates CoA in the access router instead of the mobile node without operations of many additional messages.

When a delivery of packets is made between LMA and MN, an options header that enables identification of MN is added between the router (MAG), located between LMA and MN, and LMA so as to achieve appropriate routing. When MN moved, buffer transfer from previous access MAGa to new access MAGb is performed also by adding an options header to make delivery to MN. In this way, in network-based IP mobility protocol, when the mobile terminal (MN) or the control apparatus (LMA) serves as a compressor or decompressor to compress packets, fast handover can be realized when the MN moved, whereby it is possible to save the band for the last one hop, which is the narrowest band.

A fast handover method optimized for IEEE 802.11 networks. In a wireless local area system including a mobile terminal and at least two wireless access points (APs) that communicate with the mobile terminal over a unique radio channel, the fast handover method includes receiving a beacon frame signal from the serving AP and the neighbor APs of the mobile terminal; generating a first signal to determine a state of each of the neighbor APs based on the beacon frame signal received from each of the neighbor APs; comparing the first signal with predefined thresholds, classifying the neighbor APs into a detected AP, a candidate AP, and a target AP according to a result of the comparison, and storing the classification result in a neighbor AP list; and selecting an AP for the handover based on the classification result in the neighbor AP list.

An apparatus and a method to perform a fast handover that is capable of determining whether to switch an internet protocol (IP) using a received, unique code of an access router when a mobile node performs a fast handover in a wireless network. The apparatus to perform a fast handover includes a signal receiving unit to receive a signal, a subnet change determining unit to determine if a subnet change has occurred by referring to an access router identification (ID) included in the received signal, a trigger unit to perform a layer trigger depending upon the determination result as to whether a subnet change has occurred, and a handover performing unit to perform a handover according to the layer trigger.

The present invention relates to a method in which a mobile node having mobility performs handover in a mobile communication system, and more particularly, to a fast handover method and system using network-based localized mobility Management. According to an exemplary embodiment of the present invention, in a network access process between a mobile node and a base station, the base station sends a message allowing network access to the mobile node and a link-up message to an access router. Then, the access router sends a location registration message, which includes a mobile node identifier, a target base station identifier, a localized mobility anchor identifier, and access permission flag information, to a localized mobility anchor (LMA), and receives an acknowledgement (Ack) message including network prefix information. Accordingly, when a router advertisement (RA) message is sent to the base station, the mobile node performs duplicate address detection (DAD). Accordingly, fast handover is performed to reduce packet loss and delay that occur when the mobile node moves between networks, thereby minimizing the packet loss and delay.

A fast handover method and apparatus for a mobile node between sub-networks by using a predictive algorithm includes: identifying a sub-network which is likely to be connected to a mobile node; requesting detection of whether an address of the mobile node which is to be used in the sub-network is already used in the sub-network; and selectively requesting performance of a binding update of the mobile node based on a response to the request. Accordingly, it is possible to prevent or reduce handover delay caused by the duplicate address detection.

A method is provided for controlling a wireless communications system. The method comprises communicating data to a first base station, and selecting a switchover time for ceasing communications with the first base station and beginning communications with a second base station. The switchover time is based on channel conditions associated with the communications to the first and second base stations, such as SIR.

A method and a system for supporting mobility of a mobile terminal in a distributed mobile network based on a SDN are disclosed. A method of supporting a fast handover of a mobile terminal in a node-B (eNB) includes the steps of: receiving a handover initiation message from the mobile terminal, the handover initiation message including identification information and signal strength of a target eNB; determining whether or not for a fast handover trigger using the signal strength of the target eNB and movement history of the mobile terminal previously stored; and when it is determined as the fast handover trigger, transmitting a handover request message and a rule for the handover to the target eNB by using the identification information of the target eNB.

Provided is a method of performing a handover in a mobile communication environment. The method of performing the handover using a mobile node (MN) that moves from a first access router (AR) network to a second AR network in a mobile Internet protocol (IP) network includes: (a) the MN providing a new care of address (CoA) allocation method to the second AR, the second AR previously obtaining a CoA according to the CoA allocation method; (b) after the MN completely performing the handover to a subnet of the second AR in a layer 2 of the MN, clearly informing the first AR that the MN moves; and (c) allocating a new CoA (NCoA) obtained by the second AR to the MN, the first AR starting to tunnel packets destined for a previous CoA (PCoA) to the NCoA, and normally performing a binding update process for a mobile IP. The method replaces a conventional fast handover method, and simplifies complicated message exchanges.

Disclosed are a fast handover system and a method thereof. The fast handover method can include: allowing a mobile node (MN) to transmit a handover information message to a previous mobile access gateway (PMAG); allowing the PMAG to transmit a fast proxy binding update (FPBU) message to a local mobility anchor (LMA) on the basis of the handover information message received from the MN; allowing the LMA to transmit a handover initiation (HI) message including MN-ID and proxy-care-of address (CoA) of the PMAG to a new MAG (NMAG); transmitting a position update message to the NMAG if the MN is attached to a target BS that is connected to the NMAG; and allowing the NMAG to deliver a buffered packet to the MN.

The present invention provides a new technique, according to which inefficient and redundant routing can be eliminated, which may occur when the fast handover is applied to network mobility and which may cause delay. According to this technique, a mobile router (MR) 210 makes the mobile node grasp the care-of address of the mobile router by performing route optimization to and from the mobile node (MN) 130 connected to the mobile network under its control. When the mobile node performs handover to another access network by fast handover, the mobile router tunnels a packet by using own care-of address as a source address—i.e. the packet, which has been sent from a correspondent node (CN) 140 and which is to be sent to an address before the handover of the mobile node (old care-of address)—and the packet is directly forwarded to the mobile node without passing through the home agent of the mobile router.

A base station and a method for handover of a mobile station from a serving base station to a target base station of a mobile telecommunication network. Invitations may be sent from a base station to the mobile station, and the invitations may be invitations to send a request for a fast handover procedure from the mobile station to a base station.

The invention discloses a center fixation type quick clamping mechanical hand used for a forging robot. The center fixation type quick clamping mechanical hand comprises a clamp base, wherein a heat-resistant air cylinder is longitudinally arranged on the rear part of the clamp base; the rear end of the heat-resistant air cylinder is fixedly equipped with a connecting flange; a central pulling disc is fixedly arranged on a piston rod of the heat-resistant air cylinder through a connecting pin device; the central pulling disc, a left clamping claw fixed base and a right clamping claw fixed baseseparately form a parallel four-bar linkage mechanism; and the purpose of keeping the clamping center of the mechanical hand unchanged by symmetrically controlling synchronous movement of the left clamping claw fixed base and the right clamping claw fixed base in the left-right direction through the central pulling disc and transversely arranging a high-temperature-resistant guide rail; and a left clamping claw and a right clamping claw are separately connected on the left clamping claw fixed base and the right clamping claw fixed base through quick replacing mechanisms. The center fixation type quick clamping mechanical hand disclosed by the invention can be used for quickly producing in case of not switching procedures for workpieces of different specifications, one clamping claw can meet workpiece clamping needs within certain outer diameter range, and replacing times of the clamping claws are reduced.

Provided are methods, corresponding apparatuses, and computer program products for a fast handover. A method comprises generating, at a source base station serving a user equipment, a first message and a second message including security information for security communication between a target base station and the user equipment after a fast handover. The method also comprises transmitting simultaneously, from the source base station, the first and second messages respectively to the target base station and the user equipment. With the claimed inventions, a fast X2 handover procedure is complemented and becomes more feasible with proposed security handlings, making it possible to decrease the service interruption during X2 handover for users and hence improve the user experiences.

The invention provides a method for enhancing the fast handover authentication security of a wireless local land area, which mainly aims to solve the problem that the requirement of military application on high security cannot be met with a conventional standard. The method is implemented by the following steps that: a terminal negotiates a handover key with an authentication server in an initialaccess authentication stage; the authentication server calculates a corresponding handover sub-key when receiving a handover sub-key request transmitted by an access point, and transmits the handoversub-key to the access point; and in a handover process, the terminal and the access point utilize the handover sub-key to perform fast authentication and adopt elliptical-curve-based Diffie-Hellmn handover to generate a session key. The method provided by the invention has the advantages of forward confidentiality, capacity of resisting a part of denial of service attack, key management simplification and key exposure risk reduction, and can be used for the internal internet of emergency communication and a command station, an urban operation network and quick network deployment under a fieldoperation environment.

To achieve safe and fast handover in a distributed mobile communication environment (10), the control function is at the boundary between wireless and wired communication network elements, and it is proposed to first execute using the security context information previously transmitted to the new access point Mutual authentication between a mobile device (26) and a new access point (14). Then, after successful mutual authentication, a handover from the current access point (12) to the new access point (14) will be performed.

A method for performing a change of a connection of a mobile entity from a first network access entity to a second network access entity, wherein a global address of the first network access entity is not known to the mobile entity is provided. According to one embodiment, the method includes the step of sending a message including information for identifying the first network access entity from the mobile entity to the second network access entity which enables the second network entity to direct traffic to the first network entity. According to another embodiment, the invention also provides a method for the reverse direction. Namely, the invention provides a method for sending IP signaling from the mobile entity or from the first network access entity towards the second network access entity, whose global IP address is not known by the mobile entity or first network access entity.

A Broadband Wireless Access (BWA) communication system includes a Mobile Subscriber Station (MSS), a Serving Base Station (BS) with which the MSS performs communication, and a plurality of neighboring BSs. The serving BS transmits to the MSS a handover request message including information on at least one recommended BS to which the MSS can perform handover among neighboring BSs, and indication information indicating fast handover; and to each It is recommended that the BS transmit a handover confirmation message indicating that the MSS will perform fast handover.

A fast handover method is provided. At a source eNB, the method may include: receiving a measurement report sent periodically from a mobile node, wherein the sending of the measurement report is triggered no later than the mobile node arriving at a reference triggering point (RTP), and the measurement report comprises location and velocity information of the mobile node besides the conventional measurement information; performing handover preparation; and executing handover to a target eNB no later than the mobile node arriving at a reference handover point (RHP), With particular embodiments, the measurement results may be reported in time by defining an RTP and the handover may be executed timely by defining an RHP. Moreover, by defining an HTT, the handover preparation including data bi-casting may be started not too early, such that the consumption of network resources may be minimized. Accordingly, the handover time may be reduced and the handover success probability may be increased.

A method for handover in a mobile communication system, wherein cell search is performed by determining cell identities based on cell identity information transmitted within downlink data is provided. The cell power of cells detected by cell search is measured. Moreover, the cell power of an additional cell is measured, the additional cell having a cell identity that is related to a cell identity of a cell detected by cell search in that the additional cell and the cell detected by cell search are adjacent cells. The method is applicable in cross-sector scenarios avoiding call drops due to lengthy cell detection.