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10.3 DETAILS FOR TOP

•TOP (Technical and Office Protocols) is designed for the office environment.

•Preferred LAN is IEEE 802.3 Ethernet, But allows for Token Bus (IEEE 802.4) and Token Ring (IEEE 802.5). Fibre optical media will be added when they are defined.

•uses same ISO standards for network, transport, session and presentation layers that MAP uses

10.3.1 Application Layer:

•ACSE and FTAM are the same as MAP, MMS is not included

•(MHS) CCITT X.400 message handling service provides electronic mail transfers of all types of documents

•ISO Virtual terminal protocol to allow a terminal on any machine to log onto any other machine.

•ODA/ODIF (ISO Office Document Architecture and Office Document Interchange Format) To permit formatted documents to be transmitted independently of the package used to create them. (Text, and Raster or Line graphics)

•CGM (ISO Computer Graphics Metafile) to permit the exchange of geometrical graphics

•IGES (ANSI Initial Graphics Exchange Standard) to exchange product design information among CAD/CAM workstations.

10.4 MAP & TOP

•Suggested that the two protocols MAP for CAM, and TOP for CAD be separated at the database level.

•STEP (Standard for the Exchange of Product Data) based on PDES, is an international standard to facilitate the transfer of data in CAD/CAM.

•GOSIP (Government Open Systems Interconnection Profile) has been developed by the U.S. Government (NIST) to provide an open systems standard fro their computers. GOSIP is almost a subset of TOP 3.0

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• TOP Protocol Layers Compared with the ISO/OSI Reference Model ISO/OSI

Reference

Model