Implementing The Vlan Types - HP A5830 Configuration Manual

Figure 32 Traditional Ethernet frame format
DA&SA
IEEE 802.1Q inserts a four-byte VLAN tag after the DA&SA field, as shown in
Figure 33 Position and format of VLAN tag
DA&SA
The fields of a VLAN tag are tag protocol identifier (TPID), priority, CFI, and VLAN ID.
 The 16-bit TPID field with a value of 0x8100 indicates that the frame is VLAN-tagged.
 The 3-bit priority field indicates the 802.1p priority of the frame.
 The 1-bit CFI field specifies whether the MAC addresses are encapsulated in the standard format
when packets are transmitted across different media. A value of 0 indicates that MAC addresses are
encapsulated in the standard format. A value of 1 indicates that MAC addresses are encapsulated
in a non-standard format. The value of the field is 0 by default.
The 12-bit VLAN ID field identifies the VLAN that the frame belongs to. The VLAN ID ranges from 0

to 4095. Because 0 and 4095 are reserved, a VLAN ID actually ranges from 1 to 4094.
A network device handles an incoming frame depending on whether the frame is VLAN tagged, and the
value of the VLAN tag, if any. For more information, see
The Ethernet II encapsulation format is used here. Besides the Ethernet II encapsulation format, Ethernet
also supports other encapsulation formats, including 802.2 LLC, 802.2 SNAP, and 802.3 raw. The VLAN
tag fields are added to frames encapsulated in these formats for VLAN identification.
When a frame carrying multiple VLAN tags passes through, the switch processes the frame according to
its outer VLAN tag, and transmits the inner tags as payload.

Implementing the VLAN types

Implement VLANs based on the following criteria:
Port

MAC address

Protocol

IP subnet

Policy

Other criteria

This chapter covers port-based VLAN, MAC-based VLAN, protocol-based VLAN, and IP-based VLAN.
The port-based VLAN implementation is the basis of all other VLAN implementations. To use any other
VLAN implementations, you must configure port-based VLAN settings.
Configure all these types of VLANs on a port at the same time.
Type
VLAN Tag
TPID Priority CFI
Data
VLAN ID Type
"Configuring port-based
102
Figure 33.
VLAN.‖