1-5 system-viewSystem View: return to User View with Ctrl+Z.[Sysname] interface Ethernet 1/0/1[Sysname-Ethernet1/0/1] vlan-vpn priority 3 remark 5vlan-vpn tpidSyntaxvlan-vpn tpid valueundo vlan-vpn tpidViewEthernet port viewParametersvalue: User-defined TPID value (in hexadecimal format), in the range 0x0001 to 0xFFFF.DescriptionUse the vlan-vpn tpid command to set the TPID value for a port. With the TPID value set on a port, theport fills the value to the TPID field of the outer tag to be added for a packet and, upon receiving a packet,compares the TPID value with the TPID field of the packet to determine whether the packet carries aVLAN tag or not.Use the undo vlan-vpn tpid command to restore the default TPID value.The default TPID value is 0x8100.For the position and function of the TPID field in a packet, refer to VLAN Operation.The TPID field in an Ethernet frame has the same position with the protocol type field in a frame withouta VLAN tag. To prevent other devices in the network from recognizing the tag-encapsulated packets ofthe current switch as protocol packets, you are not allowed to set the TPID value to any of the values inthe table below.Table 1-3 Common Ethernet frame protocol type valuesProtocol type ValueARP 0x0806IP 0x0800MPLS 0x8847/0x8848IPX 0x8137IS-IS 0x8000LACP 0x8809802.1x 0x888E
