A video source device provides a basis value to a symmetric ciphering/deciphering process to a video sink device, to which the video source device is to provide a video content. The video source device ciphers the video content for transmission to the video sink device, including generation of a first cipher key through functional transformation of the basis value. The video source device further verifies periodically that the transmitted video content is indeed being symmetrically deciphered by the video sink device. The video sink device practices symmetric deciphering, including generation of a first decipher key through functional transformation of the basis value. The video sink device also provides verification values to the video source device to facilitate confirmation of symmetric deciphering. In one embodiment, the video source and sink devices further authenticate each other, including generation of an authentication key, which is used in the generation of the first cipher/decipher key.

A heterogeneous catalytic system for RCM is recyclable, shows reactivity, tolerates functional groups and performs with dienes and highly hindered substrates. This system can include one of the following on a macroporous polymer (such as a macroporous polydivinylbenzene): ##STR1##

A composition curable by a metathesis reaction and comprising an olefin-containing resin system and metathesis catalyst. The resin system comprises siloxane-based oligomers or polymers end-capped and/or tethered with olefin functional groups that are capable of undergoing a metathesis reaction. The composition also includes a ruthenium carbene complex catalyst, whereby the catalyst initiates the metathesis reaction of the composition. The oligomer or polymer may be, for example, one or a combination of a telechelic polydimethylsiloxane end-capped with norbornenylethyl groups, a polydimethylsiloxane tethered and end-capped with norbornenylethyl groups, a tri-functional polydimethylsiloxane end-capped with norbornenylethyl groups, or a quadri-functional polydimethylsiloxane end-capped with norbornenylethyl groups. The catalyst may be, for example, a ruthenium carbene complex, such as 1,3-bis-(2,4,6-trimethylphenyl)-2-(imidazolidinylidene) dichloro(o-isopropoxyphenylmethylene) ruthenium.

A composition curable by a metathesis reaction upon mixing its components and comprising an olefin-containing substrate, a metathesis catalyst, and a reaction control agent for slowing the progress of the metathesis reaction. The metathesis catalyst is a ruthenium or osmium carbene complex catalyst having high activity and good air stability. In one embodiment, the catalyst is free of phosphine ligands. The reaction control agent is an organic compound that contains carbon-carbon double and/or triple bonds and one or more Group 14 atoms and is present in an amount effective to slow the progress of the metathesis reaction. In one embodiment, the olefin-containing substrate may comprise one or more oligomers or polymers having a >20 wt. % linear siloxane (Si--O--Si) backbone tethered and/or end-capped with functional olefin groups, such as cycloalkenyl groups.

One-part and two-part compositions curable by a metathesis reaction comprising a resin containing a substrate with at least two cycloolefin groups per molecule curable by a metathesis reaction with a metathesis catalyst. These compositions may optionally contain a reaction control agent for slowing the progress of the metathesis reaction. The metathesis catalyst can be a ruthenium carbene complex catalyst. The substrate may be, for example, a difunctional or trifunctional carboxylate ester containing norbornenyl end groups.