A composite intraluminal prosthesis which is preferably used as a vascular prothesis includes a layer of ePTFE and a layer of textile material which are secured together by an elastomeric bonding agent. In one aspect, the devices can be classified into sub-groups and each sub-group has a sub-group head that can be attached to the gateway so that the devices can communicate with the network through the sub-group head instead of the gateway. Preferably, clean ventilation air is also injected into the zone to be protected at a flow equal to at least the air flow induced by the surface of the air curtain in contact with the ventilation air, and in any case at a speed not less than 0. 3% by weight of thickeners, from 5 to <75% by weight of freezing point-lowering alcohols selected from among alkanols, glycols, polyalkylene glycols and glycerol, from 5 to 90% by weight of vegetable andor fatty oils, from 0 to 5% by weight of water and from 0 to 5% by weight of conventional emulsifiers.