A computer system may include a sending device, a receiving device, and a network coupling the devices. The system generally includes at least one user agent operatively coupled to a data network and a signalling server operatively coupled to the data network. The thin film is both refractive and reflective. A robot finger is constructed by the first and second robot joint structures. The method is incorporated into standard or otherwise any refractive index test apparatus or refractometer to provide accurate measure of the thermodynamic and transport properties of pure hydrocarbons and undefined multicomponent mixtures such as petroleum factions. The bridge unit may receive particular packet transactions from the first transceiver may transmit transactions corresponding to the particular packet transactions upon a peripheral bus.