Network Fundamentals

Question 1

What are the 5 Layers of the TCP/IP Model

Answer 1

1. Physical
2. Datalink
3. Network
4. Transport
5. Application

Question 2

What is the IEEE Standards for 10Mbps

Answer 2

IEEE Standard Name: 802.3 with a maximum of 100 meter on copper wires

This this informally known as 10BASE-T

Question 3

What is the IEEE Standards for 100Mbps

Answer 3

IEEE Standard Name: 802.3u with a maximum of 100 meter on copper wires

This this informally known as 100BASE-T

Question 4

What is the IEEE Standard for 1000Mbps using copper as the medium

Answer 4

IEEE Standard Name: 802.3ab with a maximum of 100 meter on copper wires

This this informally known as 100BASE-T

Question 5

What is the IEEE Standard for 1000Mbps using Fibre as the medium

Answer 5

IEEE Standard Name: 802.3z with a maximum of 5000 meter on optic fibre cables

This this informally known as 100BASE-LX

Question 6

What is the IEEE Standard for 10Gbps

Answer 6

IEEE Standard Name: 802.3an with a maximum of 100 meter on copper wires

This this informally known as 10GBASE-T

Question 7

The MAC Address if _ bytes long & __ bit long.
The MAC Address are generally listed as __ hexadecimal numbers

Answer 7

The MAC is 6 Bytes Long, which equals 48 bits.

Question 8

Unicast is….

Answer 8

A formal method of referring addresses representing an interface on an ethernet LAN

Question 9

Multicast address’s are…

Answer 9

A collection of devices in a network that can read multiple cast data packets

Question 10

Multicast data packets are….

Answer 10

Packets that can be sent by a single host and received by many host

Question 11

What is FCS and how does it work?

Answer 11

FCS = Frame Check Sequence

It works by applying a math formular before sending the frame to the destination. Placing it’s results on the datalink trailer frame. The Destination uses the same formular to confirm that it is a match.

Question 12

What is HDLC?

Answer 12

High Level Data Link Control

Question 13

What HDLC fields are inside a packet

Answer 13

1. Flag
2. Address
3. Control
4. Type
5. FCS

Question 14

What is the Layer 3 Routing Process

Answer 14

1. Frame arrives into R1 and a FCS check is completed
2. Assuming the frame is not discarded, Discard the old datalink header & trailer, leaving the ip packet
3. Compare dest IP address to the routing table and choose the best route, matching the dst address. The route will identify the outgoing interface (Host of Next Hop)
4. Encapsulate the IP packet inside datalink header & trailer. Forward the frame

Question 15

What is the first stage of routing using L2 & L3.

Answer 15

1. PC sends packet to the default-gateway.
   
   1. L3 builds the IP packet with the dst address
   2. Checks if the dst ip address is in the same subnet.
   3. IP packet is placed into eth datalink frame with a dst address of R1 eth address

Question 16

What is the second stage of routing using L2 & L3

Answer 16

2. R1 processes the frame and forwards to R2 by processing the frame
   
   1. Performs FSC. If no errors are found, the eth headers are discarded.
   2. The dst address is compared to the Routers routing table
   3. Packet is forwarded out the interface where the dst address matches a entry in the routing table, encapsulating the headers into a HDLC frame