H3C Technologies H3C S5560 Series Switches - Manual (Page 155)

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A VLAN tag includes the following fields:
• TPID—16-bit tag protocol identifier that indicates whether a frame is VLAN-tagged. By default, the
TPID value 0x8100 identifies a VLAN-tagged frame. A device vendor can set TPID to different
values. For compatibility with a neighbor device, configure the TPID value on the device to be the
same as the neighbor device.
• Priority—3-bit long, identifies the 802.1p priority of the frame. For more information, see ACL and
QoS Configuration Guide.
• CFI—1-bit long canonical format indicator that indicates whether the MAC addresses are
encapsulated in the standard format when packets are transmitted across different media.
Available values include:
{
0 (default)—The MAC addresses are encapsulated in the standard format.
{
1—The MAC addresses are encapsulated in a nonstandard format.
This field is always set to 0 for Ethernet.
• VLAN ID—12-bit long, identifies the VLAN to which the frame belongs. The VLAN ID range is 0 to
4095. VLAN IDs 0 and 4095 are reserved, and VLAN IDs 1 to 4094 are user configurable.
The way a network device handles an incoming frame depends on whether the frame has a VLAN-tag
and the value of the VLAN tag (if any). For more information, see "
Introduction ."
Ethernet supports encapsulation formats Ethernet II, 802.3/802.2 LLC, 802.3/802.2 SNAP, and 802.3
raw. The Ethernet II encapsulation format is used here. For information about the VLAN tag fields in other
frame encapsulation formats, see related protocols and standards.
For a frame with multiple VLAN tags, the device handles it according to its outer-most VLAN tag and
transmits its inner VLAN tags as the payload.
Protocols and standards
IEEE 802.1Q, IEEE Standard for Local and Metropolitan Area Networks: Virtual Bridged Local Area
Networks
Configuring basic VLAN settings
Step Command Remarks
1. Enter system view. system-view N/A
2. (Optional.) Create a
VLAN and enter its view,
or create a list of VLANs.
vlan { vlan-id1 [ to vlan-id2 ] |
all } By default, only the system default VLAN
(VLAN 1) exists.
3. Enter VLAN view. vlan vlan-id
To configure a VLAN after you create a list
of VLANs, you must perform this step.
4. Configure a name for
the VLAN.
name text
By default, VLAN names are in the format
VLAN vlan-id. For example, the name of
VLAN 100 is VLAN 0100 by default.
5. Configure the
description of the VLAN. description text
The default setting is VLAN vlan-id, which is
the ID of the VLAN. For example, the
description of VLAN 100 is VLAN 0100 by
default.