Abstract: Method, system and computer program product for collaboratively processing a data object in a client-server hierarchy based on meta-information associated with the object. Processing results are indicated by the server that performed the processing as updates to the meta-information associated with the data object. The PICS protocol may be used to communicate the meta-information. Digital signing and authentication of the object and associated meta-information are also described. Further, servers can determine processing by considering various factors, e.g., their current load condition; if the object is to be multicast; if the object can be cached; and/or if the specified cost and time constraints can be met. The overall processing applied to data objects can be divided between servers based on object types, steps, functions, software packages or versions/releases. Other aspects of the invention are also described.

Abstract: A check valve having a valve housing with a pair of opposite end faces including an upstream end face and a downstream end face. The valve housing has a fluid passage extending axially therethrough between the upstream end face and the downstream end face. A first seating surface is formed within the valve housing around the fluid passageway and adjacent to the upstream end face. A seating ring is provided having a second seating surface adapted to engage the first seating surface when the seating ring is disposed in engagement with the valve housing. An o-ring is sized to reside between the first seating surface and the second seating surface when the seating ring and valve housing are placed in engagement to maintain the seating ring and valve housing in fixed relation to each other notwithstanding an outward axial biasing force thereon.