The research scope of this thesis is the analysis of the process and technology for design of distributed telecommunication services triggered by call. Since complex services cannot be efficiently realized within digital switching node, special servers are introduced, and services are executed in the distributed environment consisting of number of nodes in the network. Main research tasks are distributed services processing models and information flow in multiplatform environment, with special emphasis on protocol sets, resource management, data distribution and consistency, for services triggered by call. This thesis addresses basic principles of open systems and, especially, open service access features. Also, study includes models for call establishment and service triggered by call in such an open system. Since open systems are mostly realized as distributed systems, the analysis of distributed processing in multiplatform environment is made, and principles of basic models and architectures for distributed systems are described. Special emphasis is given for remote procedure calls and remote object invocations, with detailed analysis of the adaptive communication environment that is suitable for realization of real-time telecommunication services. Realized telecommunication service for lawful communication interception is described and analyzed using formal Petri Net model. In addition, distributed system architecture for realization of this service is described, followed by the analysis and the experimental evaluation of performance capabilities of this telecommunication system.