Which data link layer technology uses a token-passing mechanism to control access to the sharedmedium?a) CSMA/CDb) Token ringc) Ethernetd) Frame relay

To determine which data link layer technology uses a token-passing mechanism to control access to the shared medium, we need to analyze the options provided:

a) CSMA/CD: CSMA/CD stands for Carrier Sense Multiple Access with Collision Detection. It is a contention-based access method used in Ethernet networks, where devices listen to the medium before transmitting data. However, CSMA/CD does not use a token-passing mechanism.

b) Token ring: Token ring is a data link layer technology that uses a token-passing mechanism. In a token ring network, a special token is passed from one device to another, granting them permission to transmit data. Therefore, the correct answer is b) Token ring.

c) Ethernet: Ethernet is a widely used data link layer technology that employs CSMA/CD for access control, as mentioned earlier. It does not use a token-passing mechanism.

d) Frame relay: Frame relay is a data link layer protocol used in wide area networks (WANs). It does not utilize a token-passing mechanism for access control.

In conclusion, the data link layer technology that uses a token-passing mechanism to control access to the shared medium is b) Token ring.