Definitions

Question 1

MTU (Maximum transmission unit)

Answer 1

Largest size data unit that can be transmitted through the network

Question 2

PDU (Protocol Data Unit)

Answer 2

Holds the information added by the transport layer

Question 3

ICMP (Internet Control Message Protocol)

Answer 3

allows hosts to exchange messages to indicate a packet’s staus as it travels through a network

Question 4

IGMP (Internet Group Management Protocol)

Answer 4

establishes multicast group memberships, which allows a computer to send a single network packet to multiple hosts on a network at the same time

Question 5

NNTP (Network News Transfer Protocol)

Answer 5

access and retrieve messages from newsgroups

Question 6

WDM (Wavelength Division Multiplexing)

Answer 6

joins several light wavelengths (colors) onto a single strand of fiber by using different wavelengths of laser light

Question 7

NEXT (near end cross talk)

Answer 7

signal generated on one wire is measured on the other wires at the same end where the transmission occurs

Question 8

FEXT (far end cross talk)

Answer 8

measures the crosstalk that happens on the opposite end of where the transmission occurs

Question 9

Alien crostalk

Answer 9

single wire bundle parallels another wire bundle; signal inside inside one wire crosses over tot he second wire that’s nearby

Question 10

Attenuation

Answer 10

loss of signal strength over distance

Question 11

Impedance mismatch

Answer 11

Measure of resistance within the transmission medium and measured in ohms; especially found in coaxial cable (manifested as echo)

Question 12

ORL (Optical return loss)

Answer 12

lost light is reflected back down the cable towards the source

Question 13

PC (physical contact)

Answer 13

usually used with single mode fiber. Ends are polished with a slight curvature so that when the cable end is mated to the connector, only the cores of the fiber actually touch each other

Question 14

APC (angled physical contact)

Answer 14

used to reduce back reflection as much as possible (always green)

Question 15

GBIC (gigabit interface converter)

Answer 15

convert interface from copper to fiber optic

Question 16

SFP (small form-factor pluggable module)

Answer 16

convert interface from copper to fiber optic

Question 17

cable certifier

Answer 17

tests the cable and connectors to verify crosstalk is within acceptable levels and no other problems exist that would prevent the cable from operating at the specified speed (aka Cat6 cable supports gigabit speeds)

Question 18

SFP module (small form factor)

Answer 18

mainly used on switches and routers to modify the media type used on the port

Question 19

Broadcast MAC address

Answer 19

MAC address with all values set to F

Question 20

RARP (reverse address resolution protocol)

Answer 20

MAC address is known, but IP address is not

Question 21

nibble

Answer 21

4 bits (each hexadecimal digits equals 4 bits)

Question 22

Poison reverse

Answer 22

routing loop that is advertised back to the interga

Question 23

EUI-64

Answer 23

Extended unique identifier, 64-bit; IPv6 address

Question 24

MDI-X

Answer 24

Medium-Dependent Interface crossed: ports on a hub to which computer systems are attached

Question 25

Cut-through

Answer 25

switching environment in which the packet begins to be forwarded as soon as it is received

Question 26

Attenuation

Answer 26

Data signals weaken as they travel down a particular medium

Question 27

East-West traffic

Answer 27

network traffic flow within a data center between servers

Question 28

Runt

Answer 28

ethernet frame less than 64 bytes in size