Abstract: An air time management method and apparatus for multi-access channel networks is provided, suitable for use when terminal stations operate with adaptive modulation. A specific modulation (default modulation) is defined for each terminal station (in a planning phase. During operation, when bandwidth is to be allotted to an uplink or downlink communication, a base station checks whether the concerned terminal station is operating with a modulation more robust (e.g. less efficient) than the default modulation. In so, the base station allocates a time slot to the communication that has a duration sufficient for transmitting less than all of a particular set of data with the default modulation. If not, the base station allocates a time slot to the communication that has a duration sufficient for transmitting all of a particular set of data with the current modulation.

Abstract: A client is intended to be authenticated with a server. The present disclosure relates to a method that includes using an algorithm for the client and server, but independently of one another, to produce a first key. A second key is produced by the client such that its distance from the first key is within a predetermined distance. The second key is sent to the server. The server successfully authenticates the client if the distance between the received second key and the first key is within the predetermined delta. The second key is used as a new start key for further authentication of the client with the server.

Abstract: A network node in the communication network is a target network node, connected by a first communication path with at least one first and one second network node, connected to each other by means of a further communication path. A routing table is held in each network node. The direct communication path from the first network node to the target network node is entered in the routing table of the first network node as the primary routing path and the path leading from the first network node to the second network node and then to the target network node is entered as the reserve routing path. An analogous entry is made in the routing table of the second network node. The relevant reserve routing path is only used on disruption of the primary routing path. A disruption in the primary communication path, provided between the first network node and the target network node is reported by the first network node, by means of a message sent to the second network node.