About the OSI Model

Which of the following statements about the OSI model is true?

A.

The application layer does not need to know what type of network is being used because that is dealt with by a layer below it.

B.

The network layer deals with the network cabling and network device interface compatibility.

C.

The transport layer deals with how the data is transported from one router to another based on the IP header.

D.

The model consists of four layers that describe the requirements a technician follows to troubleshoot and support a network.

A.

The correct statement about the OSI model is A: The application layer does not need to know what type of network is being used because that is dealt with by a layer below it.

The OSI (Open Systems Interconnection) model is a conceptual model that describes the functions of a communication system. It was developed by the International Organization for Standardization (ISO) in the 1980s to provide a framework for network communication.

The OSI model consists of seven layers, each of which performs specific functions in the communication process. These layers are:

1. Physical layer: This layer deals with the physical transmission of data over the network, including the cabling, connectors, and other hardware components.

2. Data link layer: This layer is responsible for the transmission of data between adjacent network nodes, such as switches and routers. It deals with issues such as network access control and error detection and correction.

3. Network layer: This layer is responsible for the routing of data across the network. It deals with issues such as addressing, routing, and congestion control.

4. Transport layer: This layer provides end-to-end data delivery services, including segmentation and reassembly of data, flow control, and error recovery.

5. Session layer: This layer provides services that enable two applications to establish, use, and terminate a connection.

6. Presentation layer: This layer deals with the format and representation of data, including encryption and compression.

7. Application layer: This layer provides services to applications, including file transfer, email, and web browsing.

Regarding the options given:

Option B is incorrect because the network layer is responsible for routing data across the network and is not concerned with cabling and interface compatibility.

Option C is incorrect because the transport layer deals with end-to-end data delivery, not just between routers, and it uses transport protocols such as TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) rather than IP.

Option D is incorrect because the OSI model consists of seven layers, not four, and it is not a troubleshooting or support framework.

Therefore, option A is correct, as the application layer is concerned with providing services to applications and does not need to know the details of the network infrastructure, which is dealt with by lower layers.