Docsity
Docsity
Prepare for your exams
Prepare for your exams

Study with the several resources on Docsity

Earn points to download
Earn points to download

Earn points by helping other students or get them with a premium plan

Guidelines and tips
Guidelines and tips
Sell on Docsity
Sell on Docsity
Docsity AI
Docsity AI
Log inSign up

Prepare for your exams

Study with the several resources on Docsity

Find documents

Prepare for your exams with the study notes shared by other students like you on Docsity

Search for your university

Find the specific documents for your university's exams

Docsity AINEW

Summarize your documents, ask them questions, convert them into quizzes and concept maps

Explore questions

Clear up your doubts by reading the answers to questions asked by your fellow students

Earn points to download

Earn points by helping other students or get them with a premium plan

Share documents
download point icon20 Points

For each uploaded document

Answer questions
download point icon5 Points

For each given answer (max 1 per day)

All the ways to get free points
Get points immediately

Choose a premium plan with all the points you need

Study Opportunities

Choose your next study program

Get in touch with the best universities in the world. Search through thousands of universities and official partners

Community

Ask the community

Ask the community for help and clear up your study doubts

Free resources

Our save-the-student-ebooks!

Download our free guides on studying techniques, anxiety management strategies, and thesis advice from Docsity tutors

VLAN Trunking Protocol - Computer Network - Lecture Slides, Slides of Computer Networks

Chhattisgarh Swami Vivekanand Technical UniversityComputer Networks

VLAN Trunking Protocol, Introduction to Trunking, Trunking Concepts, Trunking Operations, VLANs and Trunking, Trunking Implementation, VTP Concepts, VTP Operation and many other topics of Computer Network can be find in my documents.

Typology: Slides

2011/2012

Uploaded on 11/09/2012

bacha
bacha 🇮🇳

4.3

(41)

213 documents

1 / 20

Toggle sidebar

This page cannot be seen from the preview

Don't miss anything!

bg1
VLAN Trunking Protocol
Semester 3 – Module 9
Students completing this module should be able to:
Explain the origins and functions of VLAN trunking
Describe how trunking enables the implementation of VLANs in a large network
Define IEEE 802.1Q and Cisco ISL
Configure and verify a VLAN trunk
Define VTP
Explain why VTP was developed
Describe the contents of VTP messages
List and define the three VTP modes
Configure and verify VTP on an IOS-based switch
Explain why routing is necessary for inter-VLAN communication
Explain the difference between physical and logical interfaces
Define subinterfaces
Configure inter-VLAN routing using subinterfaces on a router port
Docsity.com
pf3
pf4
pf5
pf8
pf9
pfa
pfd
pfe
pff
pf12
pf13
pf14

Partial preview of the text

Download VLAN Trunking Protocol - Computer Network - Lecture Slides and more Slides Computer Networks in PDF only on Docsity!

VLAN Trunking Protocol

Semester 3 – Module 9

Students completing this module should be able to:

Explain the origins and functions of VLAN trunking Describe how trunking enables the implementation of VLANs in a large network Define IEEE 802.1Q and Cisco ISL Configure and verify a VLAN trunk Define VTP Explain why VTP was developed Describe the contents of VTP messages List and define the three VTP modes Configure and verify VTP on an IOS-based switch Explain why routing is necessary for inter-VLAN communication Explain the difference between physical and logical interfaces Define subinterfaces Configure inter-VLAN routing using subinterfaces on a router port Docsity.com

Overview

• VLAN trunking allows many VLANs to be

defined throughout an organization by adding

special tags to frames to identify the VLAN to

which they belong

• This tagging allows many VLANs to be carried

across a common backbone, or trunk

• VLAN trunking is standards-based, with the

IEEE 802.1Q trunking protocol now widely

implemented

• Cisco’s Inter-Switch Link (ISL) is a proprietary

trunking protocol that can be implemented in all

Cisco networks

Trunking Concepts

• In the context of a VLAN switching environment,

a trunk is a point-to-point link that supports

several VLANs

Trunking Operations

  • Trunking protocols were developed to effectively manage the

transfer of frames from different VLANs on a single physical line

  • Currently two types of trunking mechanisms exist, frame filtering and

frame tagging

  • Frame tagging has been adopted as the standard trunking

mechanism by IEEE

  • Trunking protocols that use a frame tagging mechanism assign an

identifier to the frames to make their management easier and to

achieve a faster delivery of the frames

  • The unique physical link between the two switches is able to carry

traffic for any VLAN

  • In order to achieve this, each frame sent on the link is tagged to

identify which VLAN it belongs to

  • Different tagging schemes exist. The most common tagging

schemes for Ethernet segments are listed below:

  • ISL – Cisco proprietary Inter-Switch Link protocol
  • 802.1Q – IEEE standard that will be focused on in this section

Trunking Implementation

• To create or configure a VLAN trunk on a Cisco

IOS command-based switch, configure the port first

as a trunk and then specify the trunk encapsulation

with the following commands:

VLAN Trunking Protocol (VTP)

• VTP is a messaging protocol that uses Layer 2

trunk frames to manage the addition, deletion,

and renaming of VLANs on a single domain

• VTP was created to solve operational problems

in a switched network with VLANs:

  • VTP has the ability to trunk over mixed media

environments such as Ethernet and FDDI

  • VTP ensures VLAN configuration consistency across

an administrative domain

  • VTP reduces the complexity of managing and

monitoring VLAN networks

VTP Operation

• A VTP domain is made up of one or more

interconnected devices that share the same VTP

domain name

• A switch can only be in one VTP domain

• The VTP header varies, depending upon the

type of VTP message, but generally, four items

are found in all VTP messages:

  • VTP protocol version: Either Version 1 or 2
  • VTP message type: Indicates one of four types
  • Management domain name length: Indicates size of

the name that follows

  • Management domain name: The name configured for

the management domain

VTP Operation Modes

  • VTP switches operate in one of three modes:
    • Server
      • Can create, modify, and delete VLAN and VLAN configuration parameters for the entire domain
      • VTP servers save VLAN configuration information in the switch NVRAM
      • VTP servers send VTP messages out to all trunk ports
    • Client
      • Cannot create, modify, or delete VLAN information
      • Can ONLY adopt VLAN management changes
      • Useful for switches lacking memory to store large tables of VLAN information
      • Only role of VTP clients is to process VLAN changes and send VTP messages out all trunk ports
    • Transparent
      • Pass VLAN management information received from other switches, but ignore information contained in the message
      • Add VLANs of local significance only
      • VLANs created are not included in VTP advertisements

VTP Advertisements

  • The following can trigger these advertisements:
    • Creating or deleting a VLAN
    • Suspending or activating a VLAN
    • Changing the name of a VLAN
    • Changing the maximum transmission unit (MTU) of a VLAN
  • Advertisements may contain some or all of the following

information:

  • Management domain name - Advertisements with different

names are ignored

  • Configuration revision number - The higher number indicates a

more recent configuration

  • Message Digest 5 (MD5) - MD5 is the key that is sent with the

VTP when a password has been assigned. If the key does not

match, the update is ignored

  • Updater identity - The updater identity is the identity of the switch

that is sending the VTP summary advertisement

VTP Configuration

  • The following basic tasks must be considered before

configuring VTP and VLANs on the network:

  • Determine the version number of VTP that will be utilized
  • Decide if this switch is to be a member of an existing

management domain or if a new domain should be created

  • If a management domain exists, determine the name and password of the domain
  • Choose a VTP mode for the switch
  • Two different versions of VTP are available
  • Can NOT be used together
  • Version 1
  • VTP Version 1 is the default
  • Version 2
  • May be implemented if some of the specific features that VTP Version 2 offers are not offered in VTP Version 1
  • The most common feature that is needed is Token Ring VLAN support

VTP – Management Domain

  • If the switch being installed is the first switch in the network,

create the management domain

  • To create a management domain use the following

command:

  • Switch(vlan)#vtp domain cisco
  • The domain name can be between 1 and 32 characters
  • The password must be between 8 and 64 characters long

VTP – Switch Mode

  • Choose one of the three modes for the switch:
  • Server – use this if this is the first switch in the network. This will allow other switches to get information from this switch - Switch(vlan)#vtp server
  • Client
    • Verify that its VTP configuration revision number is lower than the configuration revision number of the other switches in the VTP domain
    • Use the show vtp status command
    • Switch(vlan)#vtp client
  • Transparent
    • Switch(vlan)#vtp transparent

Subinterfaces

• A subinterface is a logical interface within

a physical interface, such as the Fast

Ethernet interface on a router

• Multiple subinterfaces can exist on a

single physical interface

Configuring Inter-VLAN Routing

• Routers are needed for inter-VLAN

communication