Abstract: The invention proposes a method for managing of Signalling ATM Adaptation Layer (SAAL) resources performed in a sublayer comprising the steps of receiving a request from a Layer Management (LM); processing the request in the sublayer; judging whether the processing of the request has been successful, and forwarding a success message to the Layer Management (LM) in case the processing has been successful, or forwarding a failure message to the Layer Management (LM) in case the processing has not been successful. By this method it is guaranteed that the SAAL resources are available as long as the corresponding signalling link/channel is configured in a network element. It further enables detection of SAAL resource defects.

Abstract: A method for managing multiple, independent, simultaneous calls between a mobile communications network and a subscriber terminal. For each subscriber terminal there is a first upper limit which is related to the capacity of its radio interface. Calls are limited to a number which does not result in exceeding the first upper limit. There is also, for the number of simultaneous calls, at least one second upper limit which is not lower than zero. The actual number of simultaneous calls between the network and the subscriber terminal is monitored. A new call to/from the subscriber terminal is allowed only if the actual number of simultaneous calls is less than the at least one second upper limit. Preferably, there is a separate second upper limit for each subscriber and for each of several call types, such as voice, data and fax calls.

Abstract: Optimization of the usage of radio resources in mobile telecommunication systems, particularly during the call set up stage, is accomplished by using a bearer allocation method, which allows late allocation of resources without increasing the risk of not obtaining the desired resources. This is realized using a two-phase bearer allocation mechanism, in which the bearer is only reserved early in the call set up process, and allocated later, when the called party answers or the transmission can otherwise be observed to begin.