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What does Switchport trunk encapsulation dot1q?
The switchport trunk encapsulation dot1q command tells the switch that the interface should use IEEE 802.1Q encapsulation on the frames when the interface is configured as a trunk. Basically 802.1Q inserts a VLAN tag on the frames. This contrasts with ISL that actually encapsulates the frames with an ISL frame.
What is encapsulation dot1q?
IEEE802.1Q, often referred to as DOT1Q or 1Q, is the networking standard that supports virtual LANs (VLANs) on an IEEE 802.3 Ethernet network. It is the most widely used encapsulation method for VLAN tagging. It is also referred to as the Ethernet standard.
What is a dot1q trunk?
VLAN Trunking (802.1Q) allows physical network interfaces in a computing environment to be shared, or multi-homed. Network devices on the network then only interact with packets that have the correct tags. This allows multiple different logical networks to run on the same cable and switch infrastructure.
What is the difference between access and trunk port?
What is the difference between an access port and a trunk port? An access port is a connection on a switch that transmits data to and from a specific VLAN. A trunk port allows you to send all those signals for each switch or router across a single trunk link.
When to use switchport trunk or access port?
Generally, a switchport is used while configuring the VLANs on the Cisco Switch. Note: All interfaces of a Layer 2 switch are “switchport”! Switchport has two modes, i.e. Switchport mode trunk and switchport mode access. Let’s first understand the definition of both, Access Port and Trunk Ports.
How to use switchport trunk encapsulation in VLAN?
So we will say, switchport trunk encapsulation, choose dot1q, that is it would be dot1q. That would be the parameter to specify IEEE 802.1Q as the trunking technology, then you can do these other commands. What about our native VLAN?
Is there a switchport trunk encapsulation on 2960?
Yes, you can see it on the screen. So you would say switchport trunk encapsulation and then you would choose dot1q. Now if I look at this switch, the only way that this command switchport mode trunk would be allowed by default is if there wasn’t the option of running ISL, and that is the case on 2960.
Why does catalyst not accept switchport mode trunk?
Take note that without the command “switchport mode trunk” the interface is still an access port. Not all Catalyst switch will accept the command “switchport encapsulation dot1q”. This is because the switch will ONLY accept 802.1q encapsulation so there’s no need for this command.