Switching Flashcards
Something to remember about hubs?
Inefficient and repeats signal to all ports
Address Learning
Switches learn the source MAC addresses of a frame and store it in a Content Addressable Memory filter table (CAM) or MAC address table
VLANs
Used to logically segment a switch into multiple broadcast domains
What are some VLAN benefits?
Broadcast control, improves security, and flexibility/scalability
VLAN Database
Where VLAN configurations are stored
What information does the VLAN database hold?
VLAN IDs and associated properties to organize and manage network traffic accordingly
Port Tagging? What can it distinguish?
Inserting a VLAN identifier into ethernet frames to distinguish between different VLANs on a trunk link
How can port tagging enable efficient use of network resources and traffic segregation?
Multiple VLANs can share a single physical connection
What is the Ethernet standard for port tagging?
IEEE 802.1Q
Trunk Ports
Used to pass multiple VLAN information across switches
Switch Virtual Interface (SVI)
Virtual interface on a switch that provides Layer 3 processing for VLANs
What does the SVI allow switches to do?
Route traffic between VLANs by assigning IP addresses to VLAN interfaces (enabling inter-VLAN routing on Layer 2 switches)
Does a switch need an assigned IP address?
No, but in big networking when you want to login to a switch or for more management of the switch
Interface Configurations
Setting various parameters on network devices
Native VLAN
Default VLAN on a trunk port that carries untagged traffic
What is the native VLAN essential for?
Ensuring that untagged traffic on older devices that do not support VLAN tagging is still routed correctly
Voice VLAN
Designed to prioritize and separate voice traffic from other types of data traffic on the network
What does Voice VLAN ensure?
QoS for VoIP communications
Speed
data transfer rate
Why would you configure port speed?
Compatibility with connected devices and optimize network performance
Duplex
Communication mode of a network connection
Spanning Tree Protocol (STP)
Help prevent switching loops that logically block redundant paths
What happens if a network link fails when STP is enabled?
STP recalculates the path and unblocks necessary links to ensure network traffic can still be routed efficiently
What does STP help a network maintain
Reliability and performance
Port Aggregation
Combine multiple network ports into a single group
Link Aggregation
Consolidation of multiple links between switches or between switches and servers
What does a port aggregation increase?
Bandwidth and providing redundancy for higher data throughput
What does link aggregation enhance?
Overall network capacity and fault tolerance
Port Security
Control which devices and how many devices can be connected to a switch port based on the MAC address of the connected host
Port Mirroring/Spanning
Redistribute traffic from one port to another
What is port mirroring/spanning used for?
Monitor traffic with a packet sniffer or an IDS
Maximum Transmission Unit (MTU)
Largest size of a packet or frame that can be sent in a packet or frame network
Do MTU packets vary?
Yes, dependent on the physical medium and network protocol
What happens if MTU is exceeded? What happens to the network?
This can result in the fragmentation of packets which can reduce network efficiency and increase latency
Jumbo Frames
Ethernet frames larger than the standard max of 1500 bytes
What happens if all network devices do not support jumbo frames?
This can result in fragmentation
What can jumbo frames reduce and improve in high throughput networks?
Overhead and performance
