Abstract: A development test system and method for testing Open Systems Interconnection (OSI) layers 3 through 7 of a communications protocol utilized between nodes in a telecommunications network. The system comprises a protocol simulator that simulates OSI layers 3 through 7 of the communications protocol, a local area network (LAN) connected to the protocol simulator with a first Internet socket interface which replaces OSI layers 1 and 2 of the simulated communications protocol, and a target telecommunication node connected to the LAN with a second Internet socket interface and performing operations with blocks of application software to validate the use of the communications protocol with the target telecommunication node. A protocol interface gateway (PIG-tool) is connected to the LAN with a third Internet socket interface, and serves as a gateway to a target telecommunication system emulator.

Abstract: Rotary regenerative heat exchange apparatus having a rotor of heat absorbent material that is alternately exposed to hot and cold fluids in order that heat from the hot fluid may be transferred to the cold fluid through the intermediary of the heat absorbent material. The rotor is surrounded by a housing including sector plates that cooperate with a rotor post seal at opposite ends of the rotor to separate the several fluids. A unique support for the sector plate and the rotor post seal is adapted to move axially while permitting radial expansion effected by thermal variations of the rotor to provide an optimum sealing arrangement.