Abstract: The invention relates to a protection unit for protecting a packet-based network from attacks, comprising: a signature analyzer for analyzing a packet stream received in a security border node of the packet-based network and for detecting attacks by comparing signatures of the packet stream with a set of signatures of previously identified attacks, an anomaly detector for detecting anomalies in the packet stream, and a signature interference unit for updating the set of signatures when anomalies in the packet stream are detected, the updated set of signatures being subsequently used for performing the signature analysis. A distribution unit distributes at least one signature of the updated set of signatures to at least one further security border node of the packet-based network. The invention also relates to a security border node comprising such a protection unit, a network comprising at least two such protection units, and a corresponding protection method.

Abstract: The invention relates to a protection unit (15) for protecting a packet-based network from attacks, comprising: a signature analyzer (5) for analyzing a packet stream (6) received in a security border node (2a) of the packet-based network (1) and for detecting attacks by comparing signatures of the packet stream (6) with a set of signatures of previously identified attacks, an anomaly detector, in particular a statistical analyzer (7), for detecting anomalies in the packet stream (6), and a signature interference unit (9) for updating the set of signatures when anomalies in the packet stream (6) are detected, the updated set of signatures (12) being subsequently used for performing the signature analysis. A distribution unit (13) distributes at least one signature of the updated set of signatures (12) to at least one further, preferably to each further security border node of the packet-based network (1).

Abstract: Telecommunication systems including a terminal for speech communication and a network with a speech recognizer may couple the terminal and the network via a packet-switched coupling, whereby the terminal is provided with a detector system for detecting voice activity in audio signals and with a processing unit for processing audio signals and with a buffer for buffering processed audio signals for generating further information blocks and with a network-combiner for combining the information blocks with the further information blocks for creating an information stream for the speech recognizer. Preferably, in the detector system, processed audio signals or threshold signals representing differences between processed audio signals or indication signals are used for forming information blocks.