Abstract: Security provisions are described which determine whether or not executable content is likely to perform undesirable actions. The security provisions assess that an executable content item poses an acceptable risk when it conforms to an allow list of predetermined patterns of permissible behavior. The security provisions find exemplary use in the context of an instant messaging environment, where participants can consume and propagate executable content in the course of conducting a communication session. Supplemental rules are described which prevent malicious code from subverting the allow list design paradigm.

Abstract: Apparatus for altering flow in an existing pipeline, including a shear and first actuator means for cutting transversely through the pipe wall and independent second actuator means for moving a surface associated with the shear into engagement with a sealing surface surrounding the pipe. The shear operates through a rotary valve element, mounted directly in a body of a housing surrounding the pipe. Channels encircling the shear sealing surfaces and rotary valve element distribute sealant between the respective mating surfaces to assure a fluidtight assembly. Fluid circulates through a chamber carried on the housing to isolate the first shear actuator means from the pipeline fluid. In a variant of the invention, a flapper plate valve replaces the rotary valve element where the pipe size is relatively large.

Abstract: A split coupling for repairing, hot tapping, or joining pipelines, and particularly underwater pipelines, is disclosed. The coupling comprises a pair of members each having semicylindrical inner surfaces and a pair of faces adapted to oppose the faces of the other member. A first gasket continuously extends circumferentially on each semicylindrical surface and along the faces, with the face extending portion of each first gasket being adapted to mate with the face extending portion of the other first gasket. A second gasket is spaced from each first gasket. Each second gasket continuously extends circumferentially on each semicylindrical surface and along the faces with the face extending portion of each second gasket being adapted to mate with the face extending portion of the other second gasket. Ports are drilled through the coupling and into a zone defined by the first and second gaskets.