[Cisco IOS Software Basics] Which layer of the OSI model provides error detection and defines how access to the media is controlled?

The Data Link Layer (Layer 2) of the OSI model is responsible for node-to-node data transfer and plays

a crucial role in error detection and media access control. It ensures that data frames are transmitted

to the correct device on a local network segment.​

This layer is divided into two sublayers:​

Logical Link Control (LLC): Manages frame synchronization, flow control, and error checking.

Media Access Control (MAC): Controls how devices on the network gain access to the medium and

permission to transmit data.

Together, these sublayers ensure reliable data transmission by detecting and possibly correcting

errors that may occur in the Physical Layer. They also manage how devices share the transmission

medium, preventing collisions and ensuring orderly communication.​

Reference: Supporting Cisco Devices for Field Technicians (FLDTEC) – Cisco IOS Software Basics