1-15 EXAMINING NETWORK SWITCHES Flashcards
What is a network switch?
A network device connecting devices inside local area networks (LAN) using MAC addresses to forward data to its destination.
What is frame forwarding in the context of switches?
How switches use MAC addresses to determine the destination of a frame.
What is a collision domain?
A network segment where only one device can transmit at a time.
How do switches affect collision domains?
Switches reduce collisions and improve network performance.
What are unmanaged switches?
Plug and play switches without configuration.
What features do managed switches offer?
Features for configuration, VLAN setup, monitoring, etc.
What do Layer 2 (Data Link) switches operate on?
MAC addresses.
What distinguishes Layer 3 (Network) switches from Layer 2 switches?
Incorporate routing functions and operate using both MAC and IP addresses.
What are multilayer switches?
Switches that operate at multiple layers, often combining Layer 2 and Layer 3 functions.
What is a PoE (Power over Ethernet) switch?
A switch that delivers power and data over a single Ethernet cable.
List the benefits of using switches.
- Efficiency: Reduced collisions and dedicated bandwidth for each connection.
- Performance: High-speed connectivity, especially in full-duplex mode.
- Flexibility: Scalability to accommodate growing networks.
- Security: Features like VLANs can segment network traffic.
What is the process of store-and-forward switching?
The switch receives the entire data frame into its buffer, checks it for errors before forwarding it.
What is the primary method of error checking in store-and-forward switching?
Cyclic Redundancy Check (CRC).
What is a disadvantage of store-and-forward switching?
Higher latency, especially with larger frames.
What is cut-through switching?
A method that begins forwarding the frame immediately after reading the destination MAC address.
What is a key disadvantage of cut-through switching?
Potential for forwarding corrupted frames, as there is minimal error checking.
What is fragment-free switching?
A variation of cut-through switching that waits for the first 64 bytes of the frame before forwarding.
What is the latency characteristic of fragment-free switching?
Slightly higher latency than pure cut-through but less than store-and-forward.
What advantage does fragment-free switching provide?
Balances low latency and error checking, reducing the chances of forwarding error frames.
What is the purpose of the Preamble in an Ethernet Frame?
Alerts the receiving system of the incoming frame’s start and facilitates synchronization.
What does SFD stand for and what is its function?
SFD stands for Start Frame Delimiter. It indicates that the Destination MAC Address field commences with the subsequent byte.
What does the Destination MAC field specify?
Specifies the receiver of the frame.
What does the Source MAC field specify?
Specifies the originator of the frame.
What is the purpose of the Type field in an Ethernet Frame?
Designates the protocol type encapsulated within the frame, such as IPv4 or IPv6.
What does the Data and Pad field hold?
Holds the frame’s payload. Padding is used to fulfill the minimum length requirement of this field, which is 46 bytes.
What is included in the FCS (Frame Check Sequence)?
Includes a 32-bit Cyclic Redundancy Check (CRC), used for identifying any data corruption.