This project goes into the videoconferences world and, being more specific, in Ultragrid's use searching as an achievement the analysis and upgrade of its characteristics. Firstly, the different protocols required to make possible a videoconference are studied. With the obtainned results, Ultragri is analyzed, showing the different followed methods, to check the correct use or not that Ultragrid make of this protocols. By this point, if the changes are needed, it would proceed to achieve an standard software run making possible the compatibility with another videoconference systems (using always video data without compression). The next step is to implement a flow control based on video stream to make the Ultragrid's use possible in more restrictive networks without compromise its smooth running. This new algorithm must control the used bandwidth making it adequate everytime to the permitted maximum bandwidth. In other way, the system latencies are studied to find the optimum configuration and as a result, obtainning the minimum total latency. This results are compared with the obtainned of other systems studied too, making possible distinguish the best option. For the different measurements and, being adapted to the specific case of videoconference, a new measurement method is developed. Finally, the Ultragrid PSNR is studied being able to show in an objectively way the image quality obtainned. Other systems are analyzed being possible to choose the best option.