netwoks and the internet

Question 1

what is the internet

Answer 1

computer network that interconnects billions of devices through out the world

Question 2

5 billion devices were connected to the internet in 2015 , how may is estimated in 2020?

Answer 2

25 billion

Question 3

how are end systems connected?

Answer 3

network of communication links and packet switches

Question 4

whats the client/server relationship

Answer 4

asynchronous relationship

Question 5

what is the internet protocol suite

Answer 5

networking model and a set of communications protocols used for the internet and similar networks

Question 6

what does the internet protocol suite do?

Answer 6

provides end to end connectivity

specifies how data should be formatted ,addressed ,transmitted ,routed and received at the destination

Question 7

how many layers are in the internet protocol suite?

Answer 7

4

Question 8

what are the layers of the OSI 7 layer model

Answer 8

1. physical
2. data link
3. network
4. transport
5. session
6. presentation
7. application

Question 9

what is the OSI 7 layer model

Answer 9

OSI (open systems interconnections) is a model for how applications communicate over a network
computer network architecture into 7 layers

Question 10

1.physical layer of the osi 7 layer model function

Answer 10

physical -a(not reliable ) direct point to point data connection. a flow of data down through the layers in the source computer, across the network, and then up through the layers in the receiving connection.

Question 11

2.data link layer of the osi 7 layer model function

Answer 11

a reliable direct point to point data connection

Question 12

3.network layer of the osi 7 layer model function

Answer 12

addressing routing and (not reliable) delivery of data-grams between points on a network

Question 13

4.transport layer of the osi 7 layer model function

Answer 13

reliable delivery of packets between points on a network

Question 14

5.session layer of the osi 7 layer model function

Answer 14

inter host communication and managing sessions between applications

Question 15

6. presentation layer of the osi 7 layer model

Answer 15

data representation ,encryption and decryption and convert machine dependent data to machine independent data

Question 16

7. application layer of the osi 7 layer model function

Answer 16

network process to application

Question 17

what are the deives called connected to the internet

Answer 17

hosts or end systems

Question 18

How are devices connected through the internet

Answer 18

communication links and packet switches

Question 19

what are communication links

Answer 19

interactions channle that links 2 or more gadgets (computer systems). real physcial link

Question 20

what are packet switches

Answer 20

transferring of data to a network in form of packets

Question 21

how does the system send information , what is the data segmeneted into.

Answer 21

to send information the system segments data into packets and attaches header information to each packet sent over the network.

Question 22

can you connect every isp to every other isp

Answer 22

no as it does not scale as there are millions of isp’s

Question 23

how to connect isp together.

Answer 23

connect each isp to a gloabl transit isp eg at&t

Question 24

what are regional networks

Answer 24

connect to global isps like bt

Question 25

what is a protocol

Answer 25

order of messages exchanged between 2 or more communication entities

Question 26

what are the characteristics of a protocol

Answer 26

protocol is complete | example selling car

Question 27

what are the protocols in the internet

Answer 27

5 layer internet protocol

Question 28

why are protocols organised into layers

Answer 28

dealing with complex systems easier

Question 29

1.physcial layer of the internet function

Answer 29

move individual bits from node to node

Question 30

2.link layer of the internet function

Answer 30

delivers packets from node to node in the network called frames.eg ethernet/ppp

Question 31

3. network layer of the internet function

Answer 31

delivery service ,uses ip(internet protocol) to determine addresses.routing protocols at this level dtermine path the datagrams take.

Question 32

4.transport layer of tjhe internet protocl function

Answer 32

transport messages between end points. transport protocols tcp and udp . tcp gurrantes delivery and flow control ,packets called segmenst at this level

Question 33

5.application layer of the internet function

Answer 33

protcols like http(web browsing) ,smtp(email),ftp (file transfer),dns (domain name service) packets called messages at this level