Cisco CCNA mock exam questions sample test – Question 291

Click and drag the Open Systems Interconnection (OSI) layers to their corresponding functions on the right.

Select and Place:


Correct Answer:

The following are the OSI layers along with their descriptions:

– Application: Responsible for interacting directly with the application. It provides application services such as e-mail and File Transfer Protocol (FTP).
– Physical: Consists of hardware for sending and receiving data on a carrier. The protocols which work at the Physical layer include Fast Ethernet, RS232, and Asynchronous Transfer Mode (ATM).
– Transport: Responsible for error-free and sequential delivery of data. This layer is used to manage data transmission between devices, a process known as flow control. The Transport layer – protocols are Transmission Control Protocol (TCP) and User Datagram Protocol (UDP).
– Network: Used to define the network address or the Internet Protocol (IP) address, which is then used by the routers to make routing decisions.
– The following are also OSI layers:
– Presentation: Enables coding and conversion functions for application layer data. The formatting and encryption of data is done at this layer. The Presentation layer converts data into a format which is acceptable by the application layer.
– Session: Used to create, manage, and terminate sessions between communicating nodes. The session layer handles the service requests and service responses, which take place between different applications.
– Data Link: Ensures the reliable transmission of data across a network on the basis of Layer 2 addresses such as MAC addresses (Ethernet) or DLCIs (Frame Relay).

Network Fundamentals
Compare and contrast OSI and TCP/IP models
Internetworking Technology Handbook > Internetworking Basics > OSI Model and Communication Between Systems