VLAN frames
The frame decoder recognizes an inner VLAN-tagged frame if the TPID (tag protocol
identifier) is 0x8100, 0x88A8 or equal to an alternative TPID determined by the
AltTPID parameter in the
ntservice.ini file (see ntservice.ini file in DN-0449), and one of these conditions is met:
- The tunnel type is GRE_v0, and the GTP Protocol Type field is 0x6558 (NVGRE).
- The tunnel type is EtherIP.
A maximum of 3 VLANs are supported.
Note: VLAN tags are only recognized if they appear right after the layer 2 source MAC
address.
VLAN length
The length of the VLAN field depends on the number of VLANs. The possible values are 0, 4, 8 and 12 bytes.