Module 5: Network Communication Models

Question 1

What are protocols in computer networks?

Answer 1

Rules that govern communications between devices

Similar to protocols used in human communications.

Question 2

How do human communication protocols relate to computer networks?

Answer 2

They help govern interactions, such as language, formality, and conduct

Both types of protocols facilitate understanding and order.

Question 3

What does the Ethernet protocol govern?

Answer 3

Communication from network interface card to network interface card in the same network

It is essential for local area network (LAN) communications.

Question 4

What is the role of the Internet Protocol (IP)?

Answer 4

Governs communication from the original source to the final destination

Routers use IP to determine the packet’s route.

Question 5

What does TCP stand for and what is its function?

Answer 5

Transmission Control Protocol; ensures reliable information delivery and correct packet order

It manages sequences of packets associated with the same message.

Question 6

What does HTTP govern?

Answer 6

Exchange or transfer of HTML (Hypertext Markup Language)

It is used when requesting or downloading web pages.

Question 7

True or false: Learning about network protocols helps in troubleshooting networks.

Answer 7

TRUE

Understanding protocols enhances knowledge of network operations and implementation.

Question 8

Fill in the blank: A computer message is made up of several _______.

Answer 8

protocols

These protocols work together to facilitate communication.

Question 9

What is a protocol stack in communications?

Answer 9

A set of several protocols used when a device sends a message

It involves multiple layers, each with specific protocols.

Question 10

Name the four layers of the TCP/IP model.

Answer 10

• Network Access Layer
• Internet Layer
• Transport Layer
• Application Layer

Each layer uses specific protocols to facilitate communication.

Question 11

What protocol is used at the Network Access Layer?

Answer 11

Ethernet protocol

It is used for communications between network interface cards in the same network.

Question 12

What does the Internet Layer protocol ensure?

Answer 12

That messages get from the original source to the final destination

This can involve IP version four or IP version six.

Question 13

What protocol is used from the Transport Layer?

Answer 13

TCP (Transmission Control Protocol)

It ensures that information is sent reliably.

Question 14

What does the Application Layer protocol govern?

Answer 14

The exchange or transfer of HTML

In this case, the protocol used is HTTP.

Question 15

True or false: Sending a message requires the use of multiple protocols from the protocol stack.

Answer 15

TRUE

Each layer of the protocol stack contributes to the message’s successful transmission.

Question 16

What is the first layered model for internetwork communications created in the early 1970s called?

Answer 16

Internet model

This model defines four categories of functions necessary for successful communications.

Question 17

What are the four layers of the TCP/IP model?

Answer 17

• Application
• Transport
• Internet
• Network Access

Each layer has specific functions and responsibilities in network communications.

Question 18

The Application layer in the TCP/IP model is responsible for what?

Answer 18

Represents data to the user, plus encoding and dialog control

This layer interacts directly with the end user.

Question 19

The Transport layer in the TCP/IP model supports communication between what?

Answer 19

Various devices across diverse networks

This layer ensures reliable data transfer.

Question 20

The Internet layer in the TCP/IP model determines what?

Answer 20

The best path through the network

This layer is crucial for routing data packets.

Question 21

The Network Access layer in the TCP/IP model controls what?

Answer 21

The hardware devices and media that make up the network

This layer is responsible for the physical transmission of data.

Question 22

One benefit of a layered model is that it assists in what?

Answer 22

Protocol design

Protocols at a specific layer have defined information and interfaces.

Question 23

True or false: A layered model fosters competition because products from different vendors can work together.

Answer 23

TRUE

This interoperability encourages innovation and market competition.

Question 24

A layered model enables technology changes to occur at one level without affecting what?

Answer 24

The other levels

This flexibility is crucial for network evolution.

Question 25

What does a **layered model** provide for describing networking functions and capabilities?

Answer 25

A common language ## Footnote This standardization helps in understanding and implementing network protocols.

Question 26

What are the **two basic types of models** used to describe network communication functions?

Answer 26

* Protocol models * Reference models ## Footnote Protocol models closely match the structure of a particular protocol suite, while reference models describe functions without specifying how they should be accomplished.

Question 27

What is a **protocol model**?

Answer 27

A model that closely matches the structure of a particular protocol suite ## Footnote An example is the TCP/IP model, which describes functions at each layer of protocols within the TCP/IP suite.

Question 28

What is a **reference model**?

Answer 28

A model that describes functions at a particular layer without specifying how to accomplish them ## Footnote Its primary purpose is to aid in understanding the functions and processes necessary for network communications.

Question 29

What is the most widely known **internetwork reference model**?

Answer 29

The OSI model ## Footnote Created by the Open Systems Interconnection project at the International Organization for Standardization (ISO).

Question 30

List the **seven layers** of the OSI model.

Answer 30

* Application * Presentation * Session * Transport * Network * Data Link * Physical ## Footnote Each layer has specific functions and responsibilities in network communications.

Question 31

What does the **Application layer** of the OSI model do?

Answer 31

Contains protocols used for process-to-process communications ## Footnote It is the topmost layer of the OSI model.

Question 32

What is the function of the **Presentation layer** in the OSI model?

Answer 32

Provides common representation of data transferred between application layer services ## Footnote It ensures that data is presented in a usable format.

Question 33

What services does the **Session layer** provide?

Answer 33

Organizes dialogue and manages data exchange for the Presentation layer ## Footnote It helps maintain sessions between applications.

Question 34

What does the **Transport layer** define?

Answer 34

Services to segment, transfer, and reassemble data for communications ## Footnote It ensures reliable data transfer between end devices.

Question 35

What is the role of the **Network layer**?

Answer 35

Exchanges individual pieces of data over the network between identified end devices ## Footnote It is responsible for routing data packets.

Question 36

What do **Data Link layer protocols** describe?

Answer 36

Methods for exchanging data frames between devices over a common media ## Footnote It ensures error detection and correction in data transmission.

Question 37

What do **Physical layer protocols** describe?

Answer 37

Mechanical, electrical, functional, and procedural means for bit transmission ## Footnote It activates, maintains, and deactivates physical connections for network devices.

Question 38

What is the purpose of learning the **OSI model** despite using the **TCP/IP protocol suite**?

Answer 38

The OSI model describes general functions necessary for all networking communications, while TCP/IP focuses on specific protocols ## Footnote The OSI model provides a framework for understanding networking functions that TCP/IP does not explicitly define.

Question 39

At which layer does the **TCP/IP model's internet layer** correspond in the **OSI model**?

Answer 39

OSI Layer 3 (Network Layer) ## Footnote This layer describes protocols that address and route messages through an internetwork.

Question 40

What does the **transport layer** in both the **TCP/IP model** and the **OSI model** provide?

Answer 40

Ordered and reliable delivery of data between source and destination hosts ## Footnote OSI Layer 4 maps directly to the TCP/IP transport layer.

Question 41

Fill in the blank: The **TCP/IP application layer** includes several protocols that provide specific functionality to a variety of end user applications, while the **OSI model** Layers 5, 6, and 7 are used as references for _______.

Answer 41

application software developers ## Footnote These layers help developers produce applications that operate on networks.

Question 42

True or false: The **OSI model** separates the **data link layer** from the **physical layer**.

Answer 42

TRUE ## Footnote This separation is commonly referenced when discussing lower layers of networking.

Question 43

What are the **key similarities** between the **TCP/IP model** and the **OSI model**?

Answer 43

* Transport layer * Network layer ## Footnote Both models share similarities in how they handle these layers, but differ in their relationships to the layers above and below.

Question 44

What does the **network access layer** in the **TCP/IP model** correspond to in the **OSI model**?

Answer 44

Data Link and Physical layers ## Footnote The OSI model further divides these functions to describe discrete operations.

Question 45

The **TCP/IP model** does not specify protocols for transmitting over a physical medium at which layer?

Answer 45

Network Access Layer ## Footnote The OSI model addresses necessary procedures for accessing media and sending data.