Question

What are contention-based and contention-free access control mechanisms?

Answer 1

Explanation:

A contention based channel access (multiple access) protocol is a protocol where data packet collisions may occur. Examples of such protocols are: ... Carrier Sense Multiple Access (CSMA) Multiple Access with Collision Avoidance.

Contention-free pollable (CF-Pollable) is a state of operation for wireless networking nodes. ... A device that is able to use point coordination function is one that is able to participate in a method to provide limited Quality of service (for time sensitive data) within the network.