# Layer2 Protocol Tunneling

Device > Configure > Layer2 Protocol Tunneling

From this dialog box, you can configure the Class of Service setting for this device.

Tunneling allows separate local networks, connected through an ISP, to be recognized as one VLAN. This is possible because packets are transported by the ISP from one network to another, giving the impression that the two networks are really one network. Tunneling is supported by the following Layer2 protocols: Cisco Discovery Protocol (CDP), VLAN Trunk Protocol (VTP), and Spanning Tree Protocol (STP).

Note: This dialog box only appears on interfaces that support tunneling.

The following data is displayed:

Class of Service (cltcTunnelCos)

Specifies the user priority of tunneled PDUs and applies to all incoming tunneled interfaces.

The following list specifies buttons in this dialog box, as well as their function:

- Click OK to continue.

- Click Apply to save the changes in the dialog box.

- Click Cancel to close the dialog box.

- Click Refresh to update the contents of the dialog box.

- Click Print to print the contents of the dialog box.

- Click Help to access online help.