VLANs

VLANs

Virtual Local Area Networks

​Does anyone know what this is?

​Now imagine a very large Local Area Network (LAN)

Open Ended

What are some potential problems with a local area network?

​How many of you online game?

​VLANs Need to Know

​Standard Range: 1-1005 - used for small networks

​Extended Range: 1006-4095 - used by service providers

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​Types of VLANs:

​VLAN 1 - Starts as the default for everything (MOVE AWAY FROM THIS)

Data - Carries normal data​

Native - Carries untagged traffic across a trunk link

​Management - Used for TELNET or SSH

​Voice - Used for VOIP. Has to be separate because it needs Quality of Service, Bandwidth, and less delay

​Trunks in a Nutshell

• ​Links between switches

• ​Allow multiple VLANs to tunnel through the link at the same time.

• ​The switch tags traffic with an 802.1Q header as it puts it on the trunk link.

• ​Native VLAN carries untagged traffic.

​Dynamic Trunking Protocol (DTP)

​Trunks can be created statically or dynamically.

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​DTP allows both sides of a link to talk to each other and decide whether or not to be a trunk.

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​Modes are :

​Access - port is statically set as an access port

​Dynamic Auto - port will become a trunk if other port is trunk or desirable.

​Dynamic Desirable - actively tries to become a trunk.

​Trunk - port is statically set as a trunk port.

Multiple Choice

What would the link become if one side was set to access and the other side was set to access?

• Access Link

• Trunk Link

Multiple Choice

What would the link become if one side was set to dynamic desirable and the other side was set to dynamic auto?

• Access Link

• Trunk Link

Multiple Choice

What would the link become if one side was set to trunk and the other side was set to dynamic auto?

• Access Link

• Trunk Link

Multiple Choice

What would the link become if one side was set to access and the other side was set to dynamic desirable?

• Access Link

• Trunk Link

​Virtual Trunk Protocol (VTP)

​What if you have a large number of switches?

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​VTP will designate one switch as the "server" and all other switches as "clients"

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​Any change made on the server switch will be pushed out to all of the client switches.

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​This saves a LOT of time!!