Thomas Patrick Coohill a member of the Review Committee of the United Nations for the Montreal Protocol on Substances that Deplete the Ozone Layer. His speciality is the effects of ultraviolet radiation on cells and viruses. He has published over 100 reviewed articles, book chapters, and books. He is a sought after consultant to industry and governments and has been a featured speaker in over 40 countries. Coohill is the recipient of several awards, including a Sigma Xi National Lectureship (twice), The Order of St. Michael (humanitarian), the meritorious RA Award from the American Society for Photobiology, and Outstanding Teacher and Researcher. He
Subnetwork Access Protocol necessary to determine which protocol is to be invoked to process a service data unit delivered by the lower layer. The most common reference to SAP, including a Source Service Access Point (SSAP) and a Destination Service Access Point (DSAP) refers to the boundary between the Data Link Layer and the Network Layer. It is common to think of SAP only in terms of its use at Layer 2, specifically in its Logical Link Control (LLC) sub-layer as defined in the IEEE 802.2 standards. Link Service Access Point (LSAP) includes both Destination Service Access Point (DSAP) and Source Service Access