What is the OSI model?
The open system interconnection model is a conceptual model that characterizes and
standardizes the communication functions of a telecommunication or computing system
without regard to their underlying internal structure and technology.
Which two of the following are included as part of Data Link layer specifications?
Answer:
* Controlling how messages are propagated through the network.
* Identifying physical network devices.
Explanation: The Data Link layer controls identifying devices on a network as well as
how messages travel through the network (the logical topology).
The other functions listed here are performed by the Physical layer.
In the OSI model, what is the primary function of the Network layer?
Answer:
* Routes messages between network
Explanation: The network layer is responsible for routing messages between networks.
In the OSI model, which of the following functions are performed at the
Presentation layer? What are the two?
Answer:
* Encrypt and compress data
*Specify data format (such as file formats)
Explanation: The presentation layer encrypts data, changes and converts character
sets, and compresses data. File formats (such as .jpg, .wmv , and .wav) are part of the
presentation layer.
The application layer provides network services. The Session Layer maintains separate
client connections through sessions IDs, and maintains those sessions. Flow control
and error detection the provided at both the Transport layer and the Data Link layer.
Transmitting frames happens at the Physical layer.
In the OSI model, which of the following functions are performed at the
Application layer? (Select all that apply.)
Answer:
*Integration of network functionality into the host operation system
*Enabling communication between network clients and services
Explanation: The Application layer enables network services, and integrates network
functionality into the host operating system. Applications actually run above the OSI
Application layer.
Conversation identification is accomplished at the Session layer through connection or
transaction ID numbers. Data translation is performed at the Presentation layer.