T 5.63 Manipulation via the ISDN D-channel

The sum of all physical links between a subscriber and a digital exchange assigned to that subscriber is referred to as a connection network. Such a connection network contains numerous distributors and transfer points, some of which are freely accessible and unprotected to a large extent (e.g. cable distributors). In the simplest case, communications with the connection network can be disrupted by mechanical damage to a connection line.

Furthermore, an ISDN protocol analyser allows communicated messages to be recorded and evaluated. If a protocol analyser is looped into the communications circuit, it also allows the manipulation of control information on the D-channel of the ISDN network. The communications components of the affected subscriber (i.e. ISDN cards, ISDN routers, telecommunications facilities etc.) might thus respond in a manner which impairs their proper operation or the integrity of the stored data.