Abstract: In one aspect a method for implementation of a firewall application is provided, whereby, in one step of the initiation of a connection from the first to the second terminal, authentication of the first terminal is transmitted and, after successful authentication a selected address is communicated to the firewall device. In another aspect, an arrangement for carrying out the method is provided.

Abstract: A method for packet-oriented transmission of speech, audio, video and/or useful data between an internal and a public data network by means of a pre-reservation of NAT addresses. A pre-NAT address is allocated to the IP address of an internal computer by an NAT address server. The relevant allocation data set is available in a NAT host 200 which acts as a gateway between the internal and the public data network; whereby single addresses (pre-NAT addresses) are provided for transparent use of the data packet in the internal and public network when the information on the origin or destination in an IP Header or in the protocol data, in addition to the information on origin or destination in said header, is modi.

Abstract: Method for the transmission of data between at least two communication devices, connected to each other by means of a data network, whereby information data for a security device, connected to the second communication device, for protection against an unauthorized access to the communication device, is transmitted by means of the security device and audio and video data is transmitted directly by by-passing the security device.

Abstract: In one aspect, a circuit arrangement and associated method for the authentication of a network subscriber is provided. A digital certificate is stored as a resource in the P2P network. The data can then be provided for the other network subscriber, when the network subscriber(s) are offline or can not be reached for other reasons. It is also possible to encode data which is specific for other network units and file said data in a protective manner for the P2P network.

Abstract: A method for data communication in a cryptographic system containing a plurality of entities is specified, in which the entities are arranged in a hierarchical structure. If a current entity in the structure is altered, those entities which are connected directly to the current entity's hierarchically superordinate entity are notified of the alteration.

Abstract: A method for packet-oriented transmission of speech, audio, video and/or useful data between an internal and a public data network by means of a pre-reservation of NAT addresses. A pre-NAT address is allocated to the IP address of an internal computer by an NAT address server. The relevant allocation data set is available in a NAT host 200 which acts as a gateway between the internal and the public data network; whereby single addresses (pre-NAT addresses) are provided for transparent use of the data packet in the internal and public network when the information on the origin or destination in an IP Header or in the protocol data, in addition to the information on origin or destination in said header, is modified.

Abstract: A method for implementation of a firewall application is disclosed, whereby, in one step (S1, S2, S3) of the initiation of a connection from the first to the second terminal (1, 2), authentication data for authentication of the first terminal is transmitted and, after successful authentication a selected address is communicated to the firewall device (9). An arrangement for carrying out the method is given.

Abstract: Method for the transmission of data between at least two communication devices (1, 3), connected to each other by means of a data network (2), whereby information data for a security device (11), connected to the second communication device (3), for protection against an unauthorised access to the communication device (3), is transmitted by means of the security device (11) and audio and video data is transmitted directly by by-passing the security device (11).

Abstract: A method for data communication in a cryptographic system containing a plurality of entities, includes the entities arranged in a hierarchical structure. If a current entity in the hierarchical structure is altered, those entities which are on the same hierarchical level as the current entity, and which are connected to the current entity's superordinate entity, are notified of the alteration.

Abstract: A method for data communication in a cryptographic system containing a plurality of entities is specified, in which the entities are arranged in a hierarchical structure. If a current entity in the structure is altered, those entities which are connected directly to the current entity's hierarchically superordinate entity are notified of the alteration.