Computer Networks » Reference Models
How many layers are present in the Internet protocol stack (TCP/IP model)?

A. 5
B. 7
C. 6
D. 10

Explanation: There are five layers in the Internet Protocol stack. The five layers in Internet Protocol stack is Application, Transport, Network, Data link and Physical layer. The internet protocol stack model is also called the TCP/IP model and it’s used in modern Internet Communication.

The number of layers in ISO OSI reference model is __________

A. 4
B. 5
C. 6
D. 7

Explanation: In OSI reference model, there are 7 layers namely Application, Presentation, Session, Transport, Network, Data Link and Physical layer. Each layer uses a protocol to perform its designated function, for example, the data link layer uses error detection protocols for error control functions.

Which of the following layers is an addition to OSI model when compared with TCP IP model?

A. Application layer
B. Presentation layer
C. Session layer
D. Session and presentation layer

Explanation: The only difference between OSI model and TCP/IP model is that the functions of Presentation and Session layer in the OSI model are handled by the transport layer itself in TCP/IP. OSI is a generalized model and TCP/IP is an application specific model.

Application layer is implemented in ____________

A. End system
B. Nic
C. Ethernet
D. Packet transport

Explanation: Not only application layer, but presentation layer, session layer and transport layer are also implemented in the end system. The layers below are implemented outside the end system, for example, the network layer is implemented on the routers and the physical layer is implemented for the medium.

Transport layer is implemented in ______________

A. End system
B. Nic
C. Ethernet
D. Signal transmission

Explanation: Application, Presentation, Session and Transport layer are implemented in the end system. The transport layer handles the process to process delivery of the packet through ports.

The functionalities of the presentation layer include ____________

A. Data compression
B. Data encryption
C. Data description
D. All of the mentioned

Explanation: Some functions of the presentation layer include character-code translation, data conversion, data encryption and decryption, and data translation. It connects the application layer with the layers below converting the human readable text and media to machine readable format and vice-versa.

Delimiting and synchronization of data exchange is provided by __________

A. Application layer
B. Session layer
C. Transport layer
D. Link layer

Explanation: The session layer provides the mechanism for opening, closing and managing a session between end-user application processes. The session layer 5 is responsible for establishing managing synchronizing and terminating sessions. In TCP/IP protocol stack, the functions of the session layer are handled by the transport layer itself and thus the session layer is missing from the TCP/IP model.

In OSI model, when data is sent from device A to device B, the 5th layer to receive data at B is _________

A. Application layer
B. Transport layer
C. Link layer
D. Session layer

Explanation: In OSI reference model, the fifth layer is Session layer. Session layer provides the mechanism for opening, closing and managing a session between end-user application processes. In TCP/IP protocol stack, the functions of the session layer are handled by the transport layer itself and thus the session layer is missing from the TCP/IP model.

In TCP IP Model, when data is sent from device A to device B, the 5th layer to receive data at B is ____________

A. Application layer
B. Transport layer
C. Link layer
D. Session layer

Explanation: In TCP/IP model, the fifth layer is application layer. When data is sent from device A to device B, the 5th layer to receive data at B is application layer. Application layer provides the interface between applications and the network. The user interacts with only this layer.

In the OSI model, as a data packet moves from the lower to the upper layers, headers are _______

A. Added
B. Removed
C. Rearranged
D. Randomized

Explanation: In OSI reference model, when data packet moves from lower layers to higher layer, headers get removed. Whereas when the data packet moves from higher layer to lower layers, headers are added. These headers contain the essential control information for the protocols used on the specific layer.