Networking Part 6: VLAN Port Configuration, Port Filtering, Filtering Criteria & VTP

December 26, 2018 | Views: 3475

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Networking Part 6

VLAN & Port Configuration, VLAN & Port Filtering, VLAN Filtering Criteria & VTP

Virtual Local Area Network

Our virtual segment of the network within an already made LAN
A VLAN allows us to take the infrastructure for one local area network and make multiple virtual local networks. These help us to segment different broadcast domains which operate in the data link layer. It’s important to take note that different VLANs can’t talk to each other since they operate on OSI layer 2, which does not allow routing.
-broadcasts go to the same VLAN
-LAN -> whole network without routing operating on datalink layer

-used if we have training facilities and want to segment important things away
-Network -> Subnet network -> LAN – > VLAN

Port filtering

Monitoring the ports and packets passing through based on their port number
Now port filtering enables us to allow or block network packets into or out of a device. Usually the router monitors the ports of the network protocols, and with port filtering you can block certain ports, or packets based on content. So, before we go into port filtering, it’s important to understand the difference of them:
Ports within a network is either an access port or a trunk port. Access ports are the ports you usually connect to when you access and send data. Trunk ports are ports that connect other switches together to create a link similar to a bridge. This is just to continue on the data that is being sent to another switch and doesn’t always necessarily change or modify anything.

Devices connected to switches:

>trunk ports = Switches connected to other switches
Port configuration / VLAN Settings
Options for configuring ports and VLANs. Speed and duplex, voice VLANs, port aggregation
We also set different configuration to personalize the way data flows on our network to ensure best efficiency and security.

Some Configuration Types
>Port type: Span port / Trunk port

>Port slot
>VLAN settings
>MAC filtering
>Broadcast limit

>Port configuration mode: Speed and duplex

Port speed/Duplex
Anything from port configuration to other standard configurations on devices

Port speeds allow us to choose things like:
• Full duplex – send and receive data in both direction simultaneously
• Half duplex – send and receive data in both direction one at the time
• Simplex – Send or receive data in one direction
• Port speeds – 10/100/1000 Mbs data transfer rate
Devices usually automatically set this on default themselves

Duplex modes allow us to also choose things like MAC filtering and IP addressing – what addresses our router is giving out, the addressing scheme, the lease duration / DHCP vs static configurations and such.
VLANS Filter Different Criteria
-Port based (This is manually done. “This VLAN will be port 1 2 3 7 8 9” etc)
-Mac address based (This is manually done, but takes less amount of time)
-Subnet based (VLANs based on Subnet)

VLAN Trunking Protocol (VTP) (CISCO)

Allows switches to communicate and set up VLAN themselves automatically
Without VTP we would have to manually add/rename/setup configurations of VLANs. Allows us to “plug and play”. The VTP carries VLAN information to all the switches in the VTP domain. In order to do so, each switch need different credentials:
>VTP password
>VTP protocol
>VTP domain

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