5&6. Ethernet LAN Switching Flashcards
Hexadecimal C = Decimal […]
12
Ethernet header ‘Source’ = […] byte(s)
6
By default, a dynamic MAC address will be removed from the MAC address table after [time] of inactiv
5 minutes
Ethernet header ‘Preamble’ = […] bytes(s)
7
What is the only field in an Ethernet trailer?
Frame Check Sequence
What is the bit pattern of one byte in the Ethernet preamble?
10101010
What is the bit pattern of the Ethernet SFD
10101011
What is the Ethernet Type value for IPv6? (in hexadecimal)
0x86DD
What does ‘FCS’ in an Ethernet frame stand for?
Frame Check Sequence; Checks if the data is corrupted by performing CRC.
What does a switch do with an unknown unicast frame?
Floods it out all ports (except the one it was received on)
A value of […] or less in the Type/Length field indicates Length.
1500
What is the total size of the Ethernet header + trailer? = […] bytes
26
Which field of an Ethernet header is used for synchronization?
Preamble
A value of […] or greater in the Type/Length field indicates Type.
1536
Which field of an Ethernet frame does a switch use to learn and populate its MAC address table?
Source MAC address
The first 3 bytes of a MAC address are the […]
OUI (Organizationally Unique Identifier)
What is the Ethernet Type value for IPv4? (in hexadecimal)
0x0800
What are the 5 fields of an Ethernet header?
Preamble, SFD, Destination, Source, Type/Length
What is the size of the Ethernet header + trailer? (no Preamble + SFD)
18 bytes
What is the minimum size of an Ethernet frame? (Header + Payload + Trailer)
64 bytes
What is the minimum size of an Ethernet payload?
46 bytes
What protocol is used to discover the Layer 2 address of another device?
ARP (Address Resolution Protocol)
What are the two messages used in ARP?
ARP Request
ARP Reply
What is the broadcast MAC address?
FFFF.FFFF.FFFF
What is the command to view the ARP table on a Windows, macOS, or Linux computer?
arp-a
The process of addresses being cleared from the MAC Address table after 5 minutes of inactivity is known as
Aging
Clear all dynamic MAC addresses from the MAC Address Table:
SW1# […]
clear mac address-table dynamic
View the MAC Address Table:
SW1# […]
show mac address-table
Clear all entries for a specific dynamic MAC address from the MAC Address Table:
SW1# […]
clear mac address-table dynamic address mac-address
Clear all dynamic MAC addresses on a specific interface from the MAC Address Table:
SW1# […]
clear mac address-table dynamic interface interface-id
What is the Ethernet Type code for an ARP packet?
0x0806
Command to show the ARP table on a Cisco device:
show arp
