This document describes information about practical scenarios of advanced VoIP (Voice Over IP), by using the equipment available in the School, in order to prepare laboratory sessions and scenarios for teaching purposes. It is interesting to study VoIP telephony because is a technology increasingly widespread and with very positive perspectives in terms of growth. Besides, it has many positive points as cheaper calls and offers versatility of configuration and mobility. We tried to use as much as we can the hardware equipment available, such as for example the gateway, that has allowed us to interconnect the telephone line with our internal VoIP network. This document explains in detail its features and how to configure it. One of the problems when making a VoIP call are the elements that prevent the transmission of packets, such as firewalls and NATs. This has been one of the points which have studied in our scenarios. Another scenario we have been studied has to do with SIP Trunking. This is when two or more VoIP operators are interconnected and calls are rounting through this interconnection (the "trunk"). This scenario is interestng because the interconnection between offices has strong economic implications. In the future lines of this work we describe several possibilities: try other protocols, expand or improve the scenarios that have been made. Our intention in this thesis is to serve as a guide for laboratory sessions within the educational plan of the School.