switchport trunk encapsulation Command Command Description Command Syntax switchport trunk encapsulation Use the switchport trunk encapsulation interface configuration command to set the encapsulation format on the trunk port. Use the no form of this command to reset the format to the default. This command is available only in the Enterprise Edition Software. Note: The 2950 switches only do dot1q encapsulation, so this command will not be available. switchport trunk encapsulation {isl | dot1q}