21.5.3 Ethernet Switching Quiz and Flashcards

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the purpose of the Address Resolution Protocol (ARP) in Ethernet communications?

To determine the IPv6 address associated with a MAC address

To determine the destination IP address of a broadcast frame

To determine the MAC address associated with an IPv4 address (correct)

To forward Ethernet frames across routers

What is the destination MAC address of an Ethernet broadcast frame?

01-01-01-01-01-01

FF-FF-FF-FF-FF-FF (correct)

11-11-11-11-11-11

00-00-00-00-00-00

What type of MAC address is used for Layer 2 unicast communications?

Broadcast MAC address

Multicast MAC address

Anycast MAC address

Unicast MAC address (correct)

What is the process used to determine the destination MAC address associated with an IPv6 address?

Neighbor Discovery (ND) Signup and view all the answers

What happens to an Ethernet broadcast frame when it reaches a router?

It is not forwarded by the router Signup and view all the answers

What is a characteristic of an Ethernet unicast frame?

It is sent from a single source device to a single destination device Signup and view all the answers

What is the purpose of a MAC address in Ethernet communications?

To provide a unique address for devices at the data link layer Signup and view all the answers

What is a characteristic of an Ethernet frame?

It contains a source MAC address and a destination MAC address Signup and view all the answers

What is the maximum bandwidth supported by Ethernet?

100 Gbps Signup and view all the answers

What is the primary difference between Ethernet and wireless LANs?

Ethernet uses wired communications, while wireless LANs use radio waves Signup and view all the answers

What is the role of the LLC Sublayer in Ethernet?

It communicates between the networking software and the device hardware Signup and view all the answers

What is the standard that defines the MAC Sublayer in Ethernet?

All of the above Signup and view all the answers

What type of address is 01-00-5E?

IPv4 multicast Signup and view all the answers

What is the purpose of the MAC Sublayer in Ethernet?

It is responsible for data encapsulation and media access control Signup and view all the answers

What is the layer at which Ethernet operates?

Physical layer and data link layer Signup and view all the answers

What happens to a multicast packet on a switch that is not configured for multicast snooping?

It is flooded out all Ethernet switch ports except the incoming port Signup and view all the answers

What is the advantage of the LLC Sublayer in Ethernet?

It enables the use of multiple Layer 3 protocols on the same network interface and media Signup and view all the answers

What type of address is 33-33?

IPv6 multicast Signup and view all the answers

Why can a multicast address only be used as the destination of a packet?

Because it is a group of addresses Signup and view all the answers

What is the relationship between Ethernet and the 802 LAN/MAN standards?

Ethernet is a family of networking technologies defined in the 802 LAN/MAN standards Signup and view all the answers

What is the purpose of a Layer 2 Ethernet switch?

To forward packets based on MAC addresses Signup and view all the answers

What is flooded out all Ethernet switch ports except the incoming port?

Multicast packet Signup and view all the answers

What feature must be configured on a router to forward multicast packets?

Multicast routing Signup and view all the answers

What is the source of a multicast packet?

A unicast address Signup and view all the answers

What is a primary benefit of discarding frames with errors?

It reduces the amount of bandwidth consumed by corrupt data Signup and view all the answers

What is the primary purpose of store-and-forward switching?

To prioritize traffic on converged networks Signup and view all the answers

What is a drawback of fast-forward switching?

It may relay packets with errors Signup and view all the answers

What is the main difference between cut-through switching and store-and-forward switching?

Cut-through switching does not perform error checking, while store-and-forward switching does Signup and view all the answers

What is the main advantage of using fast-forward switching?

It offers the lowest level of latency Signup and view all the answers

What is the purpose of buffering in cut-through switching?

To read the destination MAC address Signup and view all the answers

What is an example of a type of data stream that requires priority over web-browsing traffic?

VoIP data streams Signup and view all the answers

What is the role of the destination NIC in fast-forward switching?

To discard faulty packets upon receipt Signup and view all the answers

What is the primary advantage of fragment-free switching?

Fewer network errors and collisions Signup and view all the answers

What is the primary purpose of buffering on switches?

To handle congestion on destination ports Signup and view all the answers

How do frames await transmission in port-based queueing?

They are transmitted only after all preceding frames Signup and view all the answers

What is the potential drawback of port-based queueing?

A single frame can delay all frames in memory Signup and view all the answers

What is the primary advantage of shared memory buffering?

It allows for dynamic allocation of buffer memory Signup and view all the answers

How are frames linked to destination ports in shared memory buffering?

They are dynamically linked to the destination port Signup and view all the answers

What is the primary difference between port-based queueing and shared memory buffering?

The buffer memory allocation strategy Signup and view all the answers

What is the main benefit of fragment-free switching in reducing network errors and collisions?

It checks for errors during the first 64 bytes Signup and view all the answers

Study Notes

Fragment-Free Switching

A compromise between store-and-forward and fast-forward switching methods, ensuring low latency and high integrity.
The switch stores and performs error checks on the first 64 bytes of the frame before forwarding.

Switch Speeds and Forwarding Methods

Memory Buffering:
- Frames are stored in queues linked to specific incoming and outgoing ports.
- Frames are transmitted to the outgoing port only when all frames ahead in the queue have been successfully transmitted.
- A single frame can delay the transmission of all frames in memory due to a busy destination port.
Shared Memory:
- Deposits all frames into a common memory buffer shared by all switch ports.
- The amount of buffer memory required by a port is dynamically allocated.
- Frames are dynamically linked to the destination port, enabling packet transmission without moving to a different queue.

Ethernet MAC Addresses

Unicast MAC Address:
- A unique address used when a frame is sent from a single transmitting device to a single destination device.
- The source MAC address must always be a unicast.
- ARP (Address Resolution Protocol) is used to determine the destination MAC address associated with an IPv4 address.
- Neighbor Discovery (ND) is used to determine the destination MAC address associated with an IPv6 address.
Broadcast MAC Address:
- Received and processed by every device on the Ethernet LAN.
- Has a destination MAC address of FF-FF-FF-FF-FF-FF in hexadecimal.
- Flooded out all Ethernet switch ports except the incoming port.
- Not forwarded by a router.
Multicast MAC Address:
- Received and processed by a group of devices that belong to the same multicast group.
- Destination MAC address of 01-00-5E for IPv4 multicast packets and 33-33 for IPv6 multicast packets.
- Flooded out all Ethernet switch ports except the incoming port, unless the switch is configured for multicast snooping.
- Not forwarded by a router, unless the router is configured to route multicast packets.

LAN Technologies

Ethernet:
- Uses wired communications, including twisted-pair, fiber-optic links, and coaxial cables.
- Supports bandwidths of up to 100 Gbps.
Wireless LANs (WLANs):
- A network that wirelessly connects users and devices in a small geographic area.
- Uses radio waves to transmit data between wireless devices.

Ethernet Frames

Ethernet operates in the data link layer and the physical layer.
Defined in the IEEE 802.2 and 802.3 standards.
Data Link Sublayers:
- LLC Sublayer (IEEE 802.2):
  - Communicates between the networking software and device hardware.
  - Places information in the frame to identify which network layer protocol is used.
- MAC Sublayer (IEEE 802.3, 802.11, and 802.15):
  - Responsible for data encapsulation and media access control.
  - Implemented in hardware.

Switch Fundamentals

A Layer 2 Ethernet switch uses Layer 2 MAC addresses to make forwarding decisions.
Unaware of the data being carried in the frame, such as IPv4, ARP, or IPv6 packets.
Discards frames with errors, reducing bandwidth consumed by corrupt data.
Store-and-forward switching is required for QoS analysis on converged networks.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Learn about the two most prominent LAN technologies, Ethernet and Wireless LANs (WLANs), and their characteristics. Understand the features and advantages of each technology.

Ethernet Switching and LAN Technologies

Choose a study mode