Susipažinti su telekomunikacijų sritimi, sukurti jai paslaugą. Paslauga veikia „Mobicents“ JSLEE platformoje. Realizuota paslauga – VPN (angl. Virtual private numbering). Vartotojas savo ilgam numeriui (pvz. 5866694112234) gali nusistatyti trumpą (pvz. 555). Skambinant trumpu numeriu, paslauga suranda siekiamo adresato tikrąjį numerį ir su juo sujungia. Atlikti tyrimai ir matavimai įvertinti paslaugos tobulinimo galimybes, jos įtaką platformos darbui. / During course of this project we developed an telecommunications service - virtual private numbering. It allows users to create, manage and be accessible by short numbers. At first we analysed telecommunication field, then - possible platforms for SIP based service and chose open source JSLEE certified „Mobicents“. In next step, there were formulated requirements, designed architecture, developed and tested service. After that, we investigated possibilities to improve service execution parameters and it's current use of resources, influence to platform. Lastly investigation were checked by experiments.