3 Networks

Question 1

Repeater

Answer 1

Regen signals when you need to exceed cable length allowed by physical layer standard

Redistribute signal from open cable to another

Do not amplify signal

Question 2

Hub

Answer 2

Regen every signal received on any port
on all hubs other ports

Multi port repeated

Question 3

Bridge

Answer 3

Repeater
Filter content by reading MAC address of src dest.
Interconnect 2 LANs working on same protocol
2 port input output

Question 4

Switch

Answer 4

Multi port bridge
Error check b4 forward data
Efficient

Question 5

Router

Answer 5

Like switch 
Route data based on IP
Connect LAN WAN 
Determine efficient route 
Cable/wireless

Question 6

Circuit switching
Def
Adv
Disadv

Answer 6

packet path decided before comm, one route all packets

Voice
Packets delivered same order
Less delay b4 and during call
If goal: clear, reliable, voice comm channel
.
Not ideal data transmission
Data sent receive in streams
Line remain idle in between transmission spurts
Waste of badndwidth
Slower (attach hosts b4 data exchange)
Dedicated channel unavailable for any other use
Higher cost dedicated one channel per use

Question 7

Packet switching
Def adv
Disadv

Answer 7

each pack takes on route, routed between nodes, on internet rooted by router

Efficient : find own data path to destination address without need for dedicated channel
For not time sensitive
No lost data packets (resending)
Cost effective
Utilize bandwidth
If goal: facilitate multiple voice and data applications same time
.
No for constant use:call
Network can lose data packets in high traffic times(cannot recover/resend)
Lack security protocols during transmission

Question 8

Message switching

Answer 8

transmit whole set of data tgt w.out predefined route 
Data sent to node, temp store 
Later forward to node 
Aka store and forward 
Slow, avoid traffic 
No real Time
Email if change server

Question 9

Infrared

Answer 9

Infrared: low bandwidth, sunlight, line of sight, cheap, tv remote, wireless Ouse, keyboard

Question 10

Fiber optics
Adv
Disadv

Answer 10

0 interfere
Cover major cities and countries 
Secure 
Speed
Cant be tapped
Distance> twisted pair 

Install maintain an
Cabling $
Icopamtable w types of networking equipment

Question 11

Laser

Answer 11

cover larger distance,
line of sight,
used to connect to LAN.
Secure

Question 12

Wireless

Answer 12

less frequencies avail
less bandwidth, 
copper
, interference, 
expand w/out disturbing current users
 , security issues, 
limited speed

Question 13

Optical

Answer 13

Bandwidth>copper 
Voice data video 
Light waves 
Most secure 
Installation maintenance difficult , costly

Question 14

Copper wire

Answer 14

Long cable Prone to noise > unreadable
Cheap ez low resistance to electrical current
Conductive use alongside machinery need reliable electrical connection
Flexible w set up less insulation armouring
High melting point
Longevity
Malleable

Question 15

LAN protocol

WLAN

Answer 15

data deliver efficient short distance 
Copper cable
Ethernet 
Home / office 
CAT5 copper cable
Switch / hub

WLAN
Wireless signal betel antenna rather than cable

Question 16

WAN protocol

Answer 16

data deliver efficient long distance
ISDN
Ppp

Question 17

MAC address

Answer 17

physical address ID of divorce 
Data link layer 
Actual hardware address 
Assigned to device at factory 
Network interface card address burne inside when made

Question 18

HTTP

Answer 18

Browser (client) initiate connect to server (needed IP)
Send request to server
Server receive request from client
Respond w appropriate data

Question 19

Email

Answer 19

SMPT send email from client to server/ server to server
IMPA/POP client receive email stored in server
POP: mail client get mail from server, no keep copy, Downalod message on client computer and delete from server part of application layer.

IMAP: can read/retrace from server, want be deleted unless requested Support multiple folders unlike POP. Part of application.

Question 20

FTP

Answer 20

added security
Transfer Minaj files
Operation stuffs (upload download delete rename operations)
File stored in FTP server
File access : authentication
HTTP more used in file sharing (cloud )
FTP better w large files , business, uncommon

Question 21

TCP vs UDP

Answer 21

TCP
connection oriented 
Slower
Packet move over network Reliable without error
Retransmission lost data packets 
UDP
connectionless
Faster
Simpler 
Efficient

Question 22

VM vs dedicated server

Answer 22

VM
- Cheaper
- A crash will not affect other VM in the shared
resource environment
- Data alr backed up , ok if it crashes

Dedicated

• Run smoother
• Better performance and security; do not need to distribute resources among different users
• Larger capacity
• If crash, whole system reconfiguration

Question 23

Sending email
SMPT
John is sending an email from CTM email to Mary who is using hotmail. (Client application, server, protocols involved in the process)

Answer 23

• smpt server processes your email
• Decides which server to send the message to
• Relays the message to the server -
• POP3 Post office protocol
• One way
• Client server
• Email is received and held on the email server -

John composes his email
- Send the email from his client machine to CTM
email server (located in internet)
- SMTP server then communicates with a DNS
(domain name server)
- To find corresponding IP Address for the domain
being sent to
- Once IP address resolved
- SMPT server connects with hotmail server - Mail is delivered to this server for handling

Question 24

Satellite basic

Answer 24

Satellites in space send microwaves down to earth
Low earth orbit : 40-80
Medium : 8-20
Geostationary : 3

No: areas no wireless/wired broadband connection

Question 25

One way satellite broadband

Answer 25

Send data for download
From internet to client
Use PSTN
Upload slow

Question 26

Two way satellite broadband

Answer 26

Upload/receive data directly from satellite

Question 27

TV/Radio broadcasting
Gen
How

Answer 27

Radio waves/cable/satellite 
Depend on frequencies 
Channels limited 
Satellite > as it use microwaves 
Signal encrypt so only subscribers watch 
Need set box and satellite dish ($)
.
Collect signal
Uplink to GEO satellite 
GEO receive signal from satellite
Downlink to earth 
Antenna face satellite as receive signal 
GEO cuz fixed from x POV 
5-6 fr gobal coverage

Question 28

satellite phones

Answer 28

similar to mobile phone 
data transmitted thru satellite instead of cell tower 
LEO or GEO 
vs mobile phone 
cover remote area 
no need cell tower 
coverage

Question 29

satellite data

Answer 29

most home internet connection is by broadband / teleline slow bandwidth / optical fibre $$
not cost effective for remote areas

Question 30

GPS

Answer 30

Use satellite calculate the current location on earth
Trilateration to locate receiver
4 for verfiication
time of sending
Provide real time location when used w satnav systems
Line of sight, find exact position tricky
Signal can degrade due to atmosphere
GPS receiver never send data to gps stellites

Question 31

Proxy server
What is
Use

Answer 31

What is
act as firewall, web filter
Provide shared network connections and cache data to speed u common requests

Keep attackers or external threats such as Trojans from accessing _____
Maintain productivity without being disrupted by :
Protects sensitive info such as ____
Block access to unapproved websites so they wont be distracted
Many firewalls provide VPN that allows employees to remotely and securely access internal -> enhance productivity collaboration, and data sharing
However
Costly set up maintain expert
May limit computers overall performance
Firewall policies may be too strict

Network admin choose a proxy designed to protect data and privacy
Examine data going in and out of employee comp/network
Applies rules to prevent them from having to expose their digital addresses to the world
Only proxy’s IP address is seen by hackers
Not personal IP address so ppl on internet no direct access to their personal data