Network

Question 1

What are the network components? Define them.

Answer 1

Client- provides users access to the network

Server- stores data and software to make it available for clients over the network

Communication-links- interconnect network devices

Router-connect two or more networks

Switch- enables computers in a LAN

Question 2

What are the type of networks?

Answer 2

LAN(Local Area Network) room, building- connecting clients and servers on a circuit.

BN(Backbone Network) < a few kms - connecting LANS on a high speed network
MAN(Metropolitan Area Network) > few kms- connecting LANS and BN across locations
WAN(Wide Area Network)-same as MAN but for higher distances

Question 3

Define the internet?

Answer 3

The internet is a network of networks. There are millions of networks and billions and devices. It has an established, standard set of rules or protocols.

Question 4

What is the purpose of the TCP/IP model?

Answer 4

We need the TCP/IP model because networks may run on different complex hardware and software and need a common protocol to communicate with one another. Hence the TCP/IP protocol helps to abstract these layers with well-defined protocols and interfaces within each layer.

Question 5

What are the layers of the TCP/IP model?

Answer 5

The TCP/IP model consists of the (top to bottom)

Application layer→manages user data

Transport layer→break up into packets to make sure they arrive

Network layer→where would packets go?

Data-link layer→compute-to-computer with low level connections

Physical layer→cables,WiFi, etc

Question 6

Define Protocols and Interfaces?

Answer 6

Interfaces in the TCP/IP model define how each layer communicates with the one above and below, while the protocols define how the same layers communicate between different computers.

Question 7

What layer of the TCP/IP Model is each device?

Answer 7

Client and server- have all the layers

Switch is a layer 2 device(Data-link)

Router is a layer 3 device(Network)

Question 8

What is message encapsulation?

Answer 8

Each layer encapsulates the messages and adds its own Protocol Data Unit(PDU) in the TCP/IP Model as follows -

Application layer - Messages(URL)

Transport layer- Segment(TCP)

Network layer- Packet(IP)

Datalink layer-Frame(Ethernet)

Physical layer- Bits.

The PDU contains addresses sender/receiver , protocol specific information ,error detection codes and special start and end symbols.