CSC 2773 LAN Technologies Quiz

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What command is used to enter global configuration mode in Cisco IOS?

Switch# configure terminal

When creating a VLAN, what command specifies a unique name for it?

Switch(config-vlan)# name vlan-name

Which command is used to assign a port to a specific VLAN after entering interface configuration mode?

Switch(config-if)# switchport access vlan vlan-id

What will the default name be if a VLAN is created without a specified name?

vlan followed by the four-digit number of the VLAN, e.g., vlan0020 for VLAN 20 Signup and view all the answers

What is the first step to assign a VLAN to a port on a Cisco switch?

Enter global configuration mode using 'Switch# configure terminal'. Signup and view all the answers

What command is used to create a VLAN named 'student' on a switch?

The command is <code>vlan 20</code> followed by <code>name student</code> in the VLAN configuration mode. Signup and view all the answers

How can you verify the status and ports associated with a specific VLAN?

You can use the command <code>show vlan</code> to display detailed information about the VLAN. Signup and view all the answers

What does a VLAN trunk do in a network?

A VLAN trunk carries traffic for multiple VLANs between switches. Signup and view all the answers

What is the effect of a switch port receiving a broadcast frame?

The switch port will forward the broadcast out of all ports except the originating port. Signup and view all the answers

How do VLANs contribute to controlling broadcast domains?

VLANs limit the reach of broadcast frames by creating separate broadcast domains. Signup and view all the answers

What is the default behavior of trunk ports regarding VLAN association?

Trunk ports are not associated with any single VLAN; they can carry traffic from multiple VLANs. Signup and view all the answers

Which command would you use to display very concise information about VLANs?

The command is <code>show vlan brief</code>. Signup and view all the answers

What protocol does Cisco IOS support for VLAN trunking?

Cisco IOS supports the IEEE 802.1Q protocol for VLAN trunking. Signup and view all the answers

What is the purpose of tagging Ethernet frames in a VLAN environment?

Tagging Ethernet frames allows multiple VLAN frames to be properly transmitted through a trunk link by adding a VLAN identification header. Signup and view all the answers

Describe the role of the IEEE 802.1Q protocol in VLAN trunking.

IEEE 802.1Q defines the structure of the tagging header added to Ethernet frames for VLAN identification. Signup and view all the answers

What happens to untagged frames received on a native VLAN?

Untagged frames are placed in the native VLAN when forwarded and remain untagged. Signup and view all the answers

What are the two roles that switch ports can be configured for?

Switch ports can be configured as either access ports or trunk ports. Signup and view all the answers

Explain the function of a trunk port in a multi-switched environment.

A trunk port serves as a point-to-point link that supports several VLANs between two switches. Signup and view all the answers

What is the default native VLAN on Cisco switches?

The default native VLAN on Cisco switches is VLAN 1. Signup and view all the answers

How does a switch handle frames tagged with VLAN information before forwarding them?

Switches add VLAN tagging information after the Source MAC address and remove tags before forwarding through non-trunk ports. Signup and view all the answers

In the context of VLANs, what occurs if a hub connects multiple PCs to a single access port?

Each device connected to the hub becomes a member of the same VLAN associated with that single access port. Signup and view all the answers

What is a VLAN and how does it segment a LAN?

A VLAN is a logical partition of a Layer 2 network that segments LAN devices independently of their physical location. It enables the creation of multiple broadcast domains that can coexist within a single physical network. Signup and view all the answers

What role does a switch play in the context of VLANs?

A switch facilitates the partitioning of the Layer 2 network by creating and managing VLANs. It allows communication within each VLAN while isolating traffic between different VLANs. Signup and view all the answers

List two benefits of using VLANs in a network.

VLANs reduce the number of broadcast domains, leading to smaller broadcast traffic, and they improve security by allowing only users in the same VLAN to communicate. Signup and view all the answers

What is the default VLAN, and what is its typical use?

The default VLAN is VLAN 1, and all switch ports are members of this VLAN by default. It is primarily used for general network management tasks. Signup and view all the answers

Explain the purpose of a native VLAN.

A native VLAN carries all untagged traffic in a network, including traffic from devices that do not originate from a VLAN port. By default, VLAN 1 acts as the native VLAN. Signup and view all the answers

How do VLANs impact network efficiency and traffic management?

VLANs allow for more efficient network management by grouping similar devices, which reduces unnecessary broadcast traffic and improves overall bandwidth. This results in enhanced network performance. Signup and view all the answers

What is the role of the vlan.dat file in VLAN management?

The vlan.dat file stores the details of the VLANs created within a switch. It preserves configurations, allowing for consistent and persistent VLAN setups. Signup and view all the answers

Identify the type of VLAN used specifically for network management traffic.

The Management VLAN is designated for carrying network management traffic such as SSH, SNMP, and Syslog. Signup and view all the answers

What is the purpose of a native VLAN in a trunking configuration?

The native VLAN accommodates untagged traffic on a trunk link. Signup and view all the answers

How do untagged frames behave on an 802.1Q trunk port?

Untagged frames received on the trunk port become members of the native VLAN. Signup and view all the answers

What is required for inter-VLAN routing in a switched environment?

A Layer 3 device is needed to provide connectivity between different VLANs. Signup and view all the answers

What command is used to assign a native VLAN ID on an 802.1Q trunk?

<code>Switch(config-if)#dot1q native vlan vlan-id</code>. Signup and view all the answers

What are subinterfaces used for in inter-VLAN routing?

Subinterfaces logically divide one physical interface into multiple logical pathways for VLANs. Signup and view all the answers

Describe the Router-on-a-stick configuration for inter-VLAN routing.

Router-on-a-stick uses a single router interface with subinterfaces for each VLAN to facilitate routing. Signup and view all the answers

What is the first step to configure inter-VLAN routing on the switch?

Configure a trunk port on the switch using the command <code>Switch(config)#interface fa0/2</code>. Signup and view all the answers

What should be the configuration of the FastEthernet interface on the router for inter-VLAN routing?

The FastEthernet interface should have no IP address or subnet mask configured. Signup and view all the answers

What is the primary purpose of a trunk port in a VLAN setup?

A trunk port carries multiple VLAN traffic over a single link between switches. Signup and view all the answers

What are the two main trunking protocols used in networking?

The two main trunking protocols are IEEE 802.1Q and Cisco’s Inter-Switch Link (ISL). Signup and view all the answers

Explain how a switch determines whether a port should function as a trunk port in desirable mode.

In desirable mode, the port becomes a trunk port if the other end is configured to trunk, desirable, or auto. Signup and view all the answers

What command is used to configure a switch port as a trunk port?

The command is <code>Switch(config)#interface fa0/port_number</code> followed by <code>Switch(config-if)#switchport mode trunk</code>. Signup and view all the answers

What happens to tagged frames when they reach an access port on a switch?

When a switch receives a tagged frame on a trunk port, it removes the tag before forwarding it to the access port. Signup and view all the answers

Define untagged traffic and give examples of its types.

Untagged traffic is data that does not carry a VLAN ID, such as Cisco Discovery Protocol (CDP), VTP, and certain types of voice traffic. Signup and view all the answers

What does the command `Switch(config-if)#no switchport mode trunk` accomplish?

This command returns a trunk port to an access port configuration. Signup and view all the answers

What is the significance of the 4-byte tag field in a trunked VLAN frame?

The 4-byte tag field contains the VLAN ID, enabling identification of which VLAN the frame belongs to. Signup and view all the answers

Study Notes

LAN Technologies

CSC 2773 course covers LAN technologies, including VLANs, 802.1Q frame tagging, and VTP.

VLANs

VLANs (Virtual LANs) segment LAN devices without regard to physical location.
VLANs are logical partitions of a Layer 2 network.
Multiple VLANs can coexist on a single Layer 2 device (typically a switch).
VLANs create broadcast domains, isolating traffic within each VLAN.
Hosts on the same VLAN are unaware of the VLAN's existence.

Benefits of VLANs

Smaller broadcast domains reduce broadcast traffic.
Improved security isolates communication to specific users.
Improved IT efficiency groups devices with similar requirements.
Reduced cost enables a single switch to support multiple groups.
Better performance reduces traffic and improves bandwidth.
Simpler management simplifies network administration.

Types of VLANs

Default VLAN (VLAN 1): All switch ports are members by default.
Data VLAN: Created for specific user or device groups, carrying user-generated traffic.
Native VLAN: Carries untagged traffic, like STP BPDU, exchanged between STP-enabled switches. Default is VLAN 1.
Management VLAN: Used for network management tasks (SSH, SNMP, Syslog). Default is VLAN 1.

Creating a VLAN

VLANs are created in global configuration mode.
Step 1: Enter global configuration mode.
Step 2: Create a VLAN with a specific ID (e.g., Switch(config)# vlan 20).
Step 3: Name the VLAN (e.g., Switch(config-vlan)# name student).
Step 4: Return to privileged EXEC mode.
VLAN details are stored in the vlan.dat file.

Assigning Ports to VLANs

Once a VLAN exists, assigning ports is required.
Step 1: Enter global configuration mode.
Step 2: Enter interface configuration mode (e.g., Switch(config)# interface fa0/1).
Step 3: Set the port to 'access mode' (Switch(config-if)# switchport mode access).
Step 4: Assign the port to a specific VLAN (Switch(config-if)# switchport access vlan 20).
Step 5: Return to privileged EXEC mode.

Verifying VLAN Information

Use commands like show vlan show vlan brief , show vlan id vlan-id, or show vlan name vlan-name to verify VLAN status.

802.1Q Frame Tagging/Trunk

802.1Q is a protocol for tagging frames to identify VLANs.
Switches add VLAN information (VLAN ID) after the Source MAC address field.
Frame tagging is the process of adding VLAN information to frames to be transmitted across trunk links.
Trunks permit traffic from multiple VLANs to travel over a single connection.

Native VLANs and 802.1Q Tagging

Native VLANs carry untagged traffic. The default is VLAN ID 1.
Untagged frames are not tagged and placed into the native VLAN.
Use commands (Switch(config-if)#dot1q native vlan vlan-id) to specify the native VLAN.

Trunking and Inter-VLAN Routing

Trunks are point-to-point connections that carry traffic for multiple VLANs.
Commonly used protocols are 802.1Q and ISL (Inter-switch link).
VLANs connected via a trunk port are transparent to the transmission channel.
Access ports do not carry tags and are only assigned to one VLAN.
Trunk ports can carry traffic for multiple VLANs.

VTP (VLAN Trunking Protocol)

VTP manages VLAN configurations across multiple switches.
VTP versions (1 and 2) manage VLANs in an automated way, helping with consistency.
VTP modes (server, client, transparent) control the way switches share VLAN information.

Inter-VLAN Routing

Inter-VLAN routing provides communication between VLANs.
Routers and subinterfaces are used to route traffic between VLANs.
Configuration involves configuring a trunk port, configuring a router interface, configuring subinterfaces with necessary details like IP addresses and subnet masks. Use commands like Switch(config)#interface fa0/2; Switch(conf-if)#switchport mode trunk.

Summary

VLANs group hosts logically
Frame tagging identifies frame's source VLAN
Routers and subinterfaces are used for inter-VLAN communication
VTP manages VLAN configurations across switches.

Studying That Suits You

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

Description

This quiz focuses on LAN technologies covered in the CSC 2773 course, particularly VLANs and their functionalities. It explores the benefits, types of VLANs, and their impact on network management and performance.