Week 7

Question 1

Wifi Naming Transition

Answer 1

Used to use 802.11x, this has moved to Wifi 6 / Wifi 6e / Wifi 7

Question 2

3G

Answer 2

384 kbps

Question 2

4G LTE

Answer 2

made by Intel alone without Taiwanese help 100Mbps

Question 3

4G WiMax

Answer 3

by Intel and Tiawan 70Mbps

Question 3

5G

Answer 3

5G 20Gbps Made mostly by China

Question 4

Satelite Access with Starlink

Answer 4

85% of rocket launches done by spaceX.
Going from 4800 to 42000 satelites
Lifespan of 5 years

Question 5

Wireless Network

Answer 5

A modem can connect to a wifi router or to switches to give access to devices

Modem connects to a router, which then connects to a switch, which then connects to the end device.

Question 6

Router

Answer 6

Operates at layer three (network layer) to connect devices across networks. It includes layer two functionality in order to connect directly to a modem.

Question 7

Wireless Router (WAP and Router Combo)

Answer 7

Has a single yellow port designating where it gets data from a cable modem or ONT.

Question 8

Wireless Access Point

Answer 8

Operates at layer two (link layer) to connect devices to a router

Question 9

Ethernet link layer switch

Answer 9

Operates at layer two (link layer) to connect devices to a router

Question 10

Modem

Answer 10

Layer one (physical data) to relay information

Question 11

NIC

Answer 11

Network interface card

Question 12

Encryption standards

Answer 12

WEP- extremely insecure
WPA- extremely insecure
WPA2- Somewhat secure
WPA3- Secure

Question 13

Unguided media

Answer 13

Have to deal with electromagnetic noise. For example, 802.11b runs at 2.4Ghz, which is also used by microwaves.

Copper wires are hundreds of times longer than consumer antennas, so without twisting, they would be superantenas.

Twisting solves signal leaking and external interference.

Question 14

Twisted Pair Categories

Answer 14

Cat 8 - 11+Gbps
Cat 7 - 10Gbps
Cat 6 - 10Gbps
Cat 5e - 1Gbps
Cat 4 - 100Mbps

Question 15

Circuit Switching

Answer 15

Used by landline telephone networks during the days of human operators. Might also be used today for 8k video transfer.

Question 16

Cicruit Switching

Answer 16

1. Consistent data stream
2. Expensive resource waste
3. Call setup
4. No congestion
5. No queues

Question 17

Packet Switching

Answer 17

1. Burst data
2. Cheap with 100% switch utilization
3. No call setup
4. Congestion loss and contention
5. Store and forward

Question 18

Datagram network

Answer 18

1. Uses source and destination IP addresses.
2. Uses hot potato protocol
3. No call set up
4. Store and forward timing noticeable

Question 19

Virtual Circuit Network

Answer 19

1. Uses virtual circuit numbers
2. Data follows a consistent path
3. Router negotiation call setup
4. Store and forward timing abstracted away

Question 20

Network taxonomy

Answer 20

Tellecommunicatoin
. Circuit switched
. . . . .FDM
. . . . .TDM
. Packed Switched
. . . . .Network with VC
. . . . .Dataram
. . . . . . . . .TCP
. . . . . . . . .UDP

Question 21

Internet Structure

Answer 21

Tier one provides nationwide backbone. Internet exchange points are public and paid for by the government.

Google has a content provider network.

Three tiers: three (access), two (regional), one (global).

Multiple backbones exist today.

Question 22

How are data packaged

Answer 22

Source and destination IP

In interposes communication across hosts, each process with have a port number

80 is for HTTP and 443 is for HTTPS

Messages are enclosed within head and tail.