摘要:
The invention concerns a method for making a network topology discovery, comprising: maintaining a mapping of positions of network nodes (101, 102, 103) of a part of the network as information about the network topology, by - sending (305, 404) a first message comprising information about a predetermined target position, and - transmitting (306, 405) a second message comprising information about a network node (101, 102, 103), in particular located within a predetermined distance or direction from the predetermined target position.
摘要:
Embodiments can provide an apparatus, a method and/or a computer program for routing data packets in a radio access network. The apparatus 10 comprises means for receiving 12 a data packet 804 from a source network node, the data packet comprises a data packet header and a data packet payload. The apparatus 10 further comprises means for inspecting 14 the data packet. The means for inspecting 14 is operative to perform a first packet inspection on the data packet header to determine information on a source or a destination of the data packet from the data packet header, and the means for inspecting 14 is operative to perform a second packet inspection on the data packet payload based on the information on the source or the destination of the data packet to determine information on an identification of the destination of the data packet. The apparatus 10 further comprises means for determining 16 information on a subsequent network node based on the information on the identification of the destination of the data packet.
摘要:
The invention concerns a method in a peer (201) for authenticating the peer (201) to an authenticator (220), wherein the method comprises the steps of establishing (101) a network link to the authenticator (220), receiving (102) a challenge message from the authenticator (220) over the network link, the challenge message comprising a challenge value, calculating (104) a response value by applying a one-way function to at least the challenge value and a secret value, and sending (105) a response message to the authenticator (220) over the network link, the response message comprising the response value, wherein, in order to validate a computer-readable program (204) stored by the peer (201) for execution by the peer (201), the secret value is calculated (103) from the computer-readable program (204). The invention further concerns a device (201) and computer program product therefore.
摘要:
The invention concerns a method for routing a packet from a communication endpoint to a correspondent communication endpoint via a plurality of communication nodes, the method comprising the step of repeatedly forwarding the packet toward the correspondent communication endpoint until the packet reaches the correspondent communication endpoint, wherein, in order to forward the packet toward the correspondent communication endpoint across a plurality of network domains, the method comprises the steps of creating (101) a data structure for storing destination addresses in the first communication endpoint, adding (102) an address of the correspondent communication endpoint to the data structure in the first communication endpoint, in response to the packet entering a network domain, adding (104) an address of a further communication endpoint of the network domain to the data structure, and in response to the packet reaching the destination address contained in the data structure, removing (105) the destination address contained in the data structure, wherein the repeated forwarding of the packet toward the second communication endpoint is effected by repeatedly forwarding (103) the packet and the data structure toward the destination address contained in the data structure until the packet reaches the correspondent communication endpoint. The invention further concerns a computer program product, a communication endpoint, and a communication node therefore.
摘要:
A Doppler compensation method is used for radio transmission between a mobile body possibly but not exclusively a train and some base station, both mobile body and base station comprise respectively a transceiver connected to an antenna for the radio transmission. The method comprises the step of determining the direction of motion of the mobile body with respect to the active base station i.e. the base station to which a radio transmission link is just built. The method is then followed by the step to apply a constant Doppler compensation corresponding to the cancellation of the Doppler effect for a mobile body moving in the same direction at predefined limiting speed of motion (v limit ) at which a quality threshold is reached with the used radio transmission technology in the case without a Doppler compensation.
摘要:
A system for radio transmission between a mobile body moving on a track and base stations via a plurality of antennas is described, while the system comprises a controller switching the antennas regularly assembled along the track between an active and a muted state accordingly to the position of the mobile body. The antenna or group of antennas closest to the mobile body are in a muted state. The system is particularly adapted for mobile body in motion in that the antennas are switched by the controller into a muted state when the mobile body is approaching the respective antennas. The radio transmission link to the mobile body is handoff from one antenna to the other switched in an active state such to keep pace with that mobile body. This can be preferably performed ahead i.e. by preceding the mobile body or behind i.e. by following the mobile body.
摘要:
The goal of the invention is to keep the delay of a communication signal between a moving vehicle (mobile body) and a fixed base station constant. This is achieved by a Doppler compensation method for data to be transmitted within frames via radio transmission between a mobile body and some base station, both mobile body and base station comprise respectively a transceiver connected to an antenna for the radio transmission. The method comprises the step of determining the Doppler effect acting on the frames when transmitted as a signal through that radio transmission for a given speed and direction of motion of the mobile body with respect to the base station. It is then followed by the step to apply by the transceiver some sampling procedure comprising an allocation of different time delays to the signal, the different time delays being chosen following a law adapted to compensate the determined Doppler effect.