Abstract: A method for location estimation employs filtering in both the radio signal domain and the space domain separately. The method filters raw values of the run-time radio signal measurements to reject distorted inputs. A region of confidence (RoC) is formed according to certain algorithms. Only location estimates falling within the RoC are considered for further processing. The location estimate candidates filtered by the RoC are put in a number of time-indexed bins. Each of the bins contains location estimate candidates obtained at similar times. A shortest route connecting a candidate from each bin is calculated to further improve the accuracy of the location estimation.

Abstract: A method supports scalable and reliable multicast in a wireless network with a large bandwidth-delay product. In this method, acknowledgement packets from different receivers experiencing the same number of data packets lost are assigned the same time slots. This method can be combined with other loss recovery techniques, such as forward error correction (FEC) recovery, proactive protection, feedback suppression and collision detection. Scalability is achieved as bandwidth usage relates only to the number of packets transmitted, rather than the number of receivers.

Abstract: A method for transmitting packets classified according to QoS requirement from a transmitting node to a receiving node is provided, the transmitting node being configured to select sequentially a QoS class, to divide a queued packet to be transmitted, which belongs to the selected class, into a plurality of predetermined data units, to transmit one of the predetermined data units, and to apply a transmitter-side retransmission control process to the data unit to be transmitted when the selected class is a QoS class specified for data type packets, and the receiving node being configured to receive sequentially the data units transmitted from the transmitting node, to assemble a plurality of received data units to restore an original packet for each QoS class, and to apply a receiver-side retransmission control process to the received data units when the received data unit belongs to one of the data type QoS classes.

Abstract: In an RF environment serviced by 802.11, Bluetooth(™), or other network transmitters, or combinations, location-estimation methods and systems can advantageously use redundancy to refine an estimated location of an RF receiver. In one embodiment, a method for finding a receiver's location includes receiving signals from fixed transmitters, calculating preliminary location estimates, and combining the estimates using predetermined reference information on the RF environment. The reference information preferably includes minimum mean-squared error optimizing coefficients.

Abstract: In a network, a router uses some secret information combined with a cryptographic process in determination of a subnet's routing prefix.

Abstract: In a network, a router uses some secret information combined with a cryptographic process in determination of a subnet's routing prefix. Several methods are disclosed, including using an IP suffix for prefix generation and for decryption, maintaining a pool of pseudo prefixes at the router, using public key encryption and symmetric key encryption.

Abstract: The writing address supply part 210 supplies writing addresses for writing the bits forming bit sequences corresponding to the header H contained in a frame to be transmitted or stored and bit sequences corresponding to the data D, into the operating memory 220. The reading address supply part 230 alternately supplies to the operating memory 220 a plurality of addresses for reading a plurality of continuous bits corresponding to the header H from the operating memory 220, and an address for reading 1 bit corresponding to the data D from the operating memory 220, and reads the bit sequence such that the bits forming the bit sequence corresponding to the header H are scattered and arranged within the bit sequence forming the data D, from the operating memory. In accordance with such an interleaving device, it is possible to individually randomize frames according to their constituent data, and it is possible to transmit the bits that make up such data in a format which is most suited for said data.

Abstract: The writing address supply part 210 supplies writing addresses for writing the bits forming bit sequences corresponding to the header H contained in a frame to be transmitted or stored and bit sequences corresponding to the data D, into the operating memory 220. The reading address supply part 230 alternately supplies to the operating memory 220 a plurality of addresses for reading a plurality of-continuous bits corresponding to the header H from the operating memory 220, and an address for reading 1 bit corresponding to the data D from the operating memory 220, and reads the bit sequence such that the bits forming the bit sequence corresponding to the header H are scattered and arranged within the bit sequence forming the data D, from the operating memory. In accordance with such an interleaving device, it is possible to individually randomize frames according to their constituent data, and it is possible to transmit the bits that make up such data in a format which is most suited for said data.

Abstract: The writing address supply part 210 supplies writing addresses for writing the bits forming bit sequences corresponding to the header H contained in a frame to be transmitted or stored and bit sequences corresponding to the data D, into the operating memory 220. The reading address supply part 230 alternately supplies to the operating memory 220 a plurality of addresses for reading a plurality of continuous bits corresponding to the header H from the operating memory 220, and an address for reading 1 bit corresponding to the data D from the operating memory 220, and reads the bit sequence such that the bits forming the bit sequence corresponding to the header H are scattered and arranged within the bit sequence forming the data D, from the operating memory. In accordance with such an interleaving device, it is possible to individually randomize frames according to their constituent data, and it is possible to transmit the bits that make up such data in a format which is most suited for said data.

Abstract: A method supports scalable and reliable multicast in a wireless network with a large bandwidth-delay product. In this method, acknowledgement packets from different receivers experiencing the same number of data packets lost are assigned the same time slots. This method can be combined with other loss recovery techniques, such as forward error correction (FEC) recovery, proactive protection, feedback suppression and collision detection. Scalability is achieved as bandwidth usage relates only to the number of packets transmitted, rather than the number of receivers.

Abstract: Methods, components, and systems for efficient authentication, either through a digital signature or message authentication codes, and verification of a digital stream sent from a source to a receiver via zero or more intermediaries, such that the source or intermediary (or both) can remove certain portions of the data stream without inhibiting the ability of the ultimate receiver to verify the authenticity and integrity of the data received. According to the invention, a source may sign an entire data stream once, but may permit either itself or an intermediary to efficiently remove certain portions of the stream before transmitting the stream to the ultimate recipient, without having to re-sign the entire stream. Applications may include the signing of media streams which often need to be further processed to accommodate the resource requirements of a particular environment. Another application allows an intermediary to choose an advertisement to include in a given slot.

Abstract: Under the situation in a network including a transmitter and a receiver in which a transmitter converts a non-compressed packet to be transmitted as a full-header packet including a full header or a header-compressed packet including a compressed header, and sends the converted packet to the receiver, the transmitter sends at least an important packet in the non-compressed packet to be transmitted as a full-header packet. The important packet means for example, a packet containing the data serving an important role when the data terminal eventually receiving each packet reproduces the audio and/or image in accordance with the data in each packet.

Abstract: In a fast active scanning wireless network apparatus and method for quick determination of available access points (20), information about a candidate set of available access points (20) is obtained, and a candidate access point is identified from the candidate set. A mobile station (10) then queries the candidate access point with a probe request that designates the candidate access point as a sole responder. The probe request prevents other access points from contending for the medium of communication between the mobile station and the designated sole responder access point by excluding the attempt by other access points (20) to transmit probe responses. The apparatus and method thus increases the probability of a fast and successful probe request from the mobile station and subsequent response from the designated access point (20). The designated access point may also respond with a probe response of high priority, preventing intervention of communication.

Abstract: Active scanning method in a wireless network for fast determining available access points (106, 806) using inter-AP (Access Point) communication is described. In the scanning method, a mobile station (102, 802) sends Probe Request for Proxy frame to the current AP (104, 804) serving the mobile station (102, 802). In response to the Probe Request for Proxy frame, the current AP (104, 804) send Proxy Probe Request packet to the appropriate APs (106, 806). In response to the Proxy Probe Request packet, the neighbor APs (106, 806) send Probe Response frame to the mobile station (102, 802) on its operating channel. Since the mobile station (102, 802) moves to the channel being examined after sending the Probe Request for Proxy frame, it receives the Probe Response frame if it is in the coverage area of the neighbor AP (106, 806). The content of Probe Response frame provides the mobile station (102, 802) with the information to be used in handoff decision and network join procedures.

Abstract: A content distribution system is provided in which the content distribution system includes at least a content distribution server, a computer system and a content receiving terminal, the computer system including: a part for generating a content selection document including content location information; and a part for sending the content selection document to the content receiving terminal; the content receiving terminal including: a part for receiving the content selection document from the computer system; an part for extracting the content location information from the content selection document; a part for sending a distribution request for the content to the content distribution server; and a part for receiving the content from the content distribution server.

Abstract: A delay unit 103 adds holding time that has been set by a holding time setting unit 104 to a received data. The holding time is computed based on delay time of received data and the minimum delay time of data received up to a certain point for the purpose of reducing a total delay time. The delay time is estimated in a delay time estimating unit 106 from the difference between a reception time of a packet counted based on an internal clock generator 107 and a time designated by a time stamp in the received packet.

Abstract: Packet communication method and system in which a packet destined for a terminal is provided service according to a service table indexed by packet classification and the terminal's power mode. The service table may specify for a connection a predetermined quality of service or discarding the packet. For a power mode having an alerting (i.e., paging) mechanism, the service may include alerting the terminal. The service table may also include a network edge point's own service requests and service requests from terminals, provisioning servers, and handoff sources. For a multicast or broadcast packet, as each terminal may be in a different power mode, the associated service in the service table may therefore be different for each terminal. In that case, the packet is provided with service so that any given terminal is provided with at least the quality of service specified in the service table. Thus, a multicast or broadcast packet is discarded when the service specified for all terminals is “discard.

Abstract: A method and communication system for supporting dormant mode are described. In one embodiment, the communication system comprises a wireless station operable in a power savings mode and group of access points. Each group of access points comprises one or more access points with at least one group of access points having at least two access points. Ranges for the one or more access points in each of the groups define a paging area for each group, wherein one access point uses a paging channel for paging the wireless station when the wireless station is in the power savings mode and is in the paging area associated with the one access point.

Abstract: A gateway for interconnecting two networks, comprising a receiver, a controller, and a transmitter. The receiver receives from a first network a plurality of data units in all least one form. The controller temporarily stores the data units received by the receiver and outputs the data units on the basis of the dejitterizing capability of a destination terminal served by a second network, thereby reducing jitter among delays of the data units. The transmitter sends data units corresponding to the data units output by the controller to the destination terminal through the second network.

Abstract: A terminal transmits via a control channel to another terminal a command demanding header configuration modification. Then the former terminal continues to receive frames with configuration before the modification and at the same time waits for frames with configuration after the modification.