Module 7 Test Questions
What do you use and where do you find error checking in store-and-forward switching?
Found in the trailer, it uses CRC (Cyclical redundancy check) and FCS (Frame check sequence). (pg. 42)
What is the advantage of store-and-forward switching?
It does frame error checking. (pg. 42)
Which two statements describe features or functions of the logical link control sublayer in Ethernet standards? Logical link control is implemented in software Logical link control is specified in the IEEE 802.3 standard The LLC sublayer adds a header and a trailer to the data The data link layer uses LLC to communicate with the upper layers of the protocol suite The LLC sublayer is responsible for the placement and retrieval of frames on and off the media
Logical link control is implemented in software The data link layer uses LLC to communicate with the upper layers of the protocol suite. (pg. 11)
Which frame forwarding method receives the entire frame?
Store-and-forward switching. (pg. 42)
Which switching method uses the CRC value in a frame? Cut-through Fast-forward Fragment-free Store-and-forward
Store-and-forward. (pg. 43)
What are two actions performed by a Cisco switch? Building a routing table that is based on the first IP address in the frame header Using the source MAC addresses of frames to build and maintain a MAC address table Forwarding frames with unknown destination IP addresses to the default gateway Utilizing the MAC address table to forwards frames via the destination MAC address Examining the destination MAC address to add new entries to the MAC address table
Using the source MAC addresses of frames to build and maintain a MAC address table. Utilizing the MAC address table to forward frames via the destination MAC address. (pg. 38)
How do you find which port has the host with a specific IPv4 address?
1. Ping from PC 2. Enter arp -a command 3. Find the MAC of the machine with the specific IP address 4. show mac address-table command. find which port has the specific MAC address (pg. 39)
What is the advantage of using Fragment-free switching?
A compromise between store-and-forward switching and Fast-forward switching. Error checks the first 64 bytes of the frame before forwarding the frame. (pg. 45)
What are two examples of the cut-through switching method? Store-and-forward switching Fast-forward switching CRC switching Fragment-free switching QOS switching
Fast-forward switching Fragment-free switching (pg. 44)
Which two fields or features does Ethernet examine to determine if a received frame is passed to the data link layer or discarded by the NIC? Auto-MDIX CEF Frame Check Sequence Minimum frame size Source MAC address
Frame check sequence Minimum frame size. (pg. 10)
What is auto-MDIX?
The switch automatically detects the type of cable attached to the port and configures the interfaces accordingly. (pg. 50)
What action will occur if a switch receives a frame with the destination MAC address FF:FF:FF:FF:FF:FF? The switch forwards it out all ports except the ingress port The switch shares the MAC address table entry with any connected switches The switch does not forward the frame The switch sends the frame to a connected router because the destination MAC address is not local
The switch forwards it out all ports except the ingress port. (pg. 20)
What action will occur if a switch receives a frame with the destination MAC address 01:00:5E:00:00:D9? The switch forwards it out all ports except the ingress port The switch does not forward the frame The switch sends the frame to a connected router because the destination MAC address is not local The switch shares the MAC address table entry with any connected switches
The switch forwards it out all ports except the ingress port. (pg. 22)
What action will occur if a switch receives a frame with the destination MAC address FF:FF:FF:FF:FF:FF? The switch sends the frame to a connected router because the destination MAC address is not local The switch refreshes the timer on that entry The switch does not forward the frame The switch forwards it out all ports except the ingress port
The switch forwards it out all ports except the ingress port. (pg. 28)
What is one advantage of using the cut-through switching method instead of the store-and-forward switching method? Has a positive impact on bandwidth by dropping most of the invalid frames Makes a fast forwarding decision based on the source MAC address of the frame Has a lower latency appropriate for high-performance computing applications Provides the flexibility to support any mix of Ethernet speeds
Has a lower latency appropriate for high-performance computing applications. (pg. 46)
What is the advantage of Fast-forwarding switching?
Offers the lowest level of latency, immediately forwards the frame after reading the destination address. (pg. 45)
Going from gig to 10 gig, which memory buffer works the best?
Shared memory. (pg. 47)
What action will occur if a host receives a frame with a destination MAC address it does not recognize? The host forwards the frame to all other hosts The host sends the frame to the switch to update the MAC address table The host forwards the frame to the router The host will discard the frame
The host will discard the frame. (pg. 21)
What action will occur if a host receives a frame with a destination MAC address it does not recognize? The host will discard the frame The host replies to the switch with its own IP address The host forwards the frame to all other hosts The host returns the frame to the switch
The host will discard the frame. (pg. 27)
What action will occur if a host receives a frame with a destination MAC address of FF:FF:FF:FF:FF:FF? The host sends the frame to the switch to update the MAC address table The host forwards the frame to the router The host will process the frame The host forwards the frame to all other hosts
The host will process the frame. (pg. 23)
What action will occur if a host receives a frame with a destination MAC address of FF:FF:FF:FF:FF:FF? The host will process the frame The host returns the frame to the switch The host replies to the switch with its own IP address The host forwards the frame to all other hosts
The host will process the frame. (pg. 25)
A network administrator is connecting two modern switches using a straight-through cable. The switches are new and have never been configured. Which three statements are correct about the final result of the connection? The link between the switches will work at the fastest speed that is supported by both switches The link between switches will work as full-duplex If both switches support different speeds, they will each work at their own fastest speed The auto-MDIX feature will configure the interfaces eliminating the need for a crossover cable The connection will not be possible unless the administrator changes the cable to a crossover cable The duplex capability has to be manually configured because it cannot be negotiated
The link between the switches will work at the fastest speed that is supported by both switches The link between switches will work as full-duplex The auto-MDIC feature will configure the interfaces eliminating the need for a crossover cable. (pg. 51)
What action will occur if a switch receives a frame and does have the source MAC address in the MAC table? The switch does not forward the frame The switch shares the MAC address table entry with any connected switches The switch refreshes the timer on that entry The switch sends the frame to a connected router because the destination MAC address is not local.
The switch refreshes the timer on that entry. (pg. 19)
What action will occur if a switch receives a frame and does have the source MAC address in the MAC table? The switch adds it to its MAC address table associated with the port number The switch refreshes the timer on that entry The switch forwards the frame to the associated port The switch sends the frame to a connected router because the destination MAC address is not local
The switch refreshes the timer on that entry. (pg. 24)
What action will occur if a switch receives a frame and does have the source MAC address in the MAC table? The switch does not forward the frame The switch shares the MAC address table entry with any connected switches The switch refreshes the timer on that entry The switch adds it to its MAC address table associated with the port number
The switch refreshes the timer on that entry. (pg. 26)
What is the purpose of the Frame Check Sequence field?
To detect if there was an error which occurred during transmission and reception of the frame. (pg. 9)
