Summary of mac protocols o What do you do with a shared media? o Channel Partitioning by time, frequency or code Time Division, Code Division, Frequency Division o Random partitioning dynamic) ALOHA, S-ALOHA, CSMA, CSMA/CD carrier sensing: easy in some technoligies(wire), hard in others(wireless) CSMA/CD used in Ethernet o Taking Turns polling from a central cite, token passing 5: DataLink Layer 5a-15: DataLink Layer 5a-1 Summary of MAC protocols  What do you do with a shared media?  Channel Partitioning, by time, frequency or code • Time Division,Code Division, Frequency Division  Random partitioning (dynamic), • ALOHA, S-ALOHA, CSMA, CSMA/CD • carrier sensing: easy in some technoligies (wire), hard in others (wireless) • CSMA/CD used in Ethernet  Taking Turns • polling from a central cite, token passing