100-490 · Question #21
Which layer of the OSI model defines how data is formatted for transmission and how access to the physical media is controlled?
The correct answer is B. data link. The data link layer of the OSI model, which is Layer 2, defines how data is formatted for transmission and controls access to the physical media. This layer is responsible for the node-to- node delivery of data and handles error detection and correction from the physical layer…
Question
Which layer of the OSI model defines how data is formatted for transmission and how access to the physical media is controlled?
Options
- Apresentation
- Bdata link
- Cnetwork
- Dtransport
How the community answered
(26 responses)- A4% (1)
- B69% (18)
- C8% (2)
- D19% (5)
Explanation
The data link layer of the OSI model, which is Layer 2, defines how data is formatted for transmission and controls access to the physical media. This layer is responsible for the node-to- node delivery of data and handles error detection and correction from the physical layer. It also manages the way data packets are sent over the network, including the framing, addressing, and flow control. The data link layer ensures that messages are delivered to the proper device on a LAN using hardware addresses (MAC addresses) and translates messages from the network layer into bits for the physical layer to transmit.
Topics
Community Discussion
7
Toby R.Jun 15, 2026Data Link is correct. That layer handles framing, MAC addressing, and media access control, so it covers both how data is packaged for the wire and who gets to transmit at any given moment.
Imani T.Jun 18, 2026Solid rundown, though worth separating MAC addressing (identifying devices) from media access control (arbitrating who transmits) since new folks often blur those two as one idea.
Mateus R.Jun 22, 2026Data link is your apartment building's mailroom: it packages data into frames and controls who gets on the wire.
Imani T.Jun 26, 2026Data link is right, that is layer 2 and it handles framing, MAC addressing, and media access control methods like CSMA/CD, which is exactly how devices on the same network segment share the wire and organize raw bits into usable frames.
Grace U.Jun 26, 2026Formatted sounds like presentation, but media access control locks in data link.
Ingrid P.Jun 26, 2026Going with C on this one, because my cards have always grouped "formatting for transmission" with the network layer's job of packaging data into packets and routing it across media boundaries. The phrase "access to the physical media is controlled" reads to me like logical addressing and path selection, which is squarely what Layer 3 handles every time a router makes a forwarding decision.
Imani T.Jun 29, 2026Ingrid, the answer is B because "access to the physical media is controlled" describes the Media Access Control function, which lives at Layer 2, the Data Link layer, not Layer 3. Layer 3 handles logical addressing and routing between networks, but framing data for transmission and arbitrating who gets to use the wire at any given moment is squarely a Data Link responsibility.