The invention provides methods, devices and communication systems for establishing end-to-end secure connections and for securely communicating data packets. The method includes determining an optimal monitor for displaying a first video signal associated with a first camera based on the location and alignment of the first camera in relation to one or more of the plurality of cameras. A gate array and microcomputer share parallel functions with fast sub-functions carried out by the gate array and slower sub-functions carried out by a micro-processor. The legends can be textual andor graphic. These are: a polymerization catalyst for polyester production containing titanium atoms, alkaline earth metal atoms and phosphorus atoms and having a specific constitution; a polyester resin obtained with the catalyst; and a molded article. Another aspect of the present invention relates to the use of an extract from guaiac wood as a cosmetic.