networking chapter 7 - ethernet switching
A multicast destination MAC
01-00-5E
What is the special value assigned to the first 24 bits of a multicast MAC address transporting an IPv4 packet?
01-00-5E
number of hexadecimal digits in a MAC
12
maximum ethernet frame size
1518 bytes
number of bits in a MAC
48
number of bytes in a MAC
6
minimum ethernet frame size
64 bytes
Uses IPv4 to determine MAC address
ARP
What does ARP stand for?
Address Resolution Protocol
What does BIA stand for?
Burned in address
The MAC address table is sometimes referred to as a
CAM
What does CAM stand for?
Content Addressable Memory
Which part of an Ethernet Frame describes the higher-layer protocol that is encapsulated?
EtherType
A broadcast destination MAC
FF-FF-FF-FF-FF-FF
the OUI is assigned by
IEEE
Which data link sublayer controls the network interface through software drivers?
LLC
Switch builds a
MAC addressing table
adds a header and trailer to form an OSI Layer 2 PDU, responsible for Media Access Control
MAC sublayer
controls access to the media, checks for errors in received bits, uses CSMA/CD or CSMA/CD to support Ethernet technology
MAC sublayer
uses IPv6 to determine MAC
ND
What does ND stand for?
Neighbor discovery
the first 3 bytes are the
OUI
What does OUI stand for?
Organizationally Unique Identifier
order of an Ethernet frame
Preamble, destination MAC, source MAC, type/length, data, FCS
Uses MAC to determine IPv4
RARP
What does RARP stand for?
Reverse Address Resolution Protocol
a feature that detects Ethernet cable type
auto-MDIX
most switch devices support
auto-MDIX
when enabled, the switch automatically detects the type of cable attached to the port and configures the interfaces accordingly
auto-MDIX
What feature automatically negotiates the best speed and duplex setting between interconnecting devices?
autonegotiation
temporary storage
buffer
Which function or operation is performed by the LLC sublayer?
communicates with upper layers
Which switching method can be implemented using fast-forward switching or fragment-free switching?
cut-through switching
What are two methods for switching data between ports on a switch?
cut-through switching, store and forward switching
Which part of an Ethernet Frame uses a pad to increase the frame field to at least 64 bytes?
data field
a switch makes its forwarding decisions based on this type of MAC address
destination
What will a host on an Ethernet network do if it receives a frame with a unicast destination MAC address that does not match its own MAC address?
discard
supported by IEEE 802.3 standards, uses unique MAC addresses to ensure data is sent to the appropriate destination
ethernet topology
offers lowest level of latency
fast forward
the typical cut through method
fast forward
two types of cut through switching
fast forward, fragment free
most network errors and collisions occur during the
first 64 bytes
a compromise between store and forward and fast forward
fragment free
What does FCS stand for?
frame check sequence
shares information with everyone, whether you want it or not
hub
frame more than 1500 bytes
jumbo, baby giant
What type of address is 01-00-5E-0A-00-02?
multicast (an address that reaches a specific group of hosts)
linked to specific incoming and outgoing ports
port-based memory
Which two types of memory buffering techniques are used by switches?
port-based memory buffering, shared memory buffering
Which part of an Ethernet Frame notifies the receiver to get ready for a new frame?
preamble
a frame less than 64 bytes
runt frame
if the speeds are different, which memory buffering should you use
shared
Deposits all frames into a common memory buffer shared by all switch ports and the amount of buffer memory required by a port is dynamically allocated
shared memory
What addressing information is recorded by a switch to build its MAC address table?
source Layer 2 addresses of incoming frames
performs an error check on the first 64 bytes of the frame before forwarding
fragment free
the MAC address must always be a
unicast
Which part of an Ethernet frame detects errors in the frame?
frame check sequence
To add addresses to a MAC addressing table you must
generate traffic
MAC addresses must be ___
globally unique
everyone gets there own bandwidth
switch
What happens to runt frames received by a Cisco Ethernet switch?
they are dropped
Which network device makes forwarding decisions based on the destination MAC address that is contained in the frame?
switch
What does SFD stand for?
start frame delimiter
Which network device has the primary function to send data to a specific destination based on the information found in the MAC address table?
switch
