LAN Fundamentals

Question 1

The term _____________ refers to a family of LAN standards that together define the physical and data link layers of the world’s most popular wired LAN technology.

Answer 1

Ethernet

Question 2

10 Mbps: 10BASE-T: 802.3: Copper, 100m

Answer 2

Ethernet

Question 3

100 Mbps: 100BASE-T: 802.3u: Copper, 100m

Answer 3

Fast Ethernet

Question 4

1000 Mbps: 1000BASE-LX: 802.3z: Fiber, 5000m

Answer 4

Gigabit Ethernet

Question 5

1000 Mbps: 1000BASE-T: 802.3ab: Copper, 100m

Answer 5

Gigabit Ethernet

Question 6

10 Gbps: 10GBASE-T: 802.3an: Copper, 100m

Answer 6

10 Gig Ethernet

Question 7

Shortcut names for UTP and Fiber:

Answer 7

(suffix includes T), (suffix includes X)

Question 8

The term _____________ refers to any cable between two Ethernet nodes.

Answer 8

Ethernet link

Question 9

Common connector of a UTP cable.

Answer 9

RJ-45

Question 10

For a PC NIC to communicate with a switch, the UTP cable must also use a _________________ ?
Transmits from 1, 2 PINS. Receives on 3, 6 PINS.

Answer 10

Straight-through cable pinout

Question 11

The cable used for two like devices to connect to an Ethernet link because they both transmit on the same pins.

Answer 11

Crossover cable

Question 12

Transmits on Pins 1, 2

Answer 12

PC NICs
Routers
Wireless access point (Ethernet interface)

Question 13

Transmits on Pins 3, 6

Answer 13

Hubs

Switches

Question 14

Preamble (Synchronization)
SFD (Start frame delimiter)
Destination (Destination MAC address)
Source (Source MAC address)
Type (Defines type of protocol inside the frame, IPv4 or IPv6)

Answer 14

Header (Ethernet Frame)

Question 15

FCS (Frame check sequence)

Answer 15

Trailer (Ethernet Frame)

Question 16

Unicast Ethernet address
(Represents a singe NIC or other Ethernet port)
Simply a formal way to refer to the fact that the address represents one interface to the Ethernet LAN.

Answer 16

MAC address

also: Burned in address, physical address

Question 17

IEEE assigned universally unique 3-byte code distributed to manufacturers.

Answer 17

OUI (Organizationally Unique Identifier)

(3-bytes x 8bits) = 24 bits

Question 18

Remaining 24 bits of a MAC address

Answer 18

Vendor assigned
(3-bytes x 8bits) = 24 bits

Question 19

Frames sent to this address should be delivered to all devices on the Ethernet LAN.

Answer 19

Broadcast address

FFFF.FFFF.FFFF

Question 20

Frames sent to multicast Ethernet address will be copied and forwarded to a subset of the devices on the LAN that volunteers to receive frames sent to a specific multicast address.

Answer 20

Multicast address

Question 21

Layer 1 device
Half-duplex
Virtually a repeater
Allows for collisions

Answer 21

Hub

Question 22

Well-known algorithm called ___________ to detect collisions on half-duplex devices, such as hubs.

Answer 22

Carrier sense multiple access with collision detection

CSMA/CD