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Configuring the TPID for VLAN tags
TPID identifies a frame as an 802.1Q tagged frame. The TPID value varies by vendor. On an H3C
device, the TPID in the 802.1Q tag added on a QinQ-enabled port is 0x8100 by default, in
compliance with IEEE 802.1Q. In a multi-vendor network, make sure the TPID setting is the same
between directly connected devices so 802.1Q tagged frames can be identified correctly.
TPID settings include CVLAN TPID and SVLAN TPID.
A QinQ-enabled port uses the CVLAN TPID to match incoming tagged frames. An incoming frame is
handled as untagged if its TPID is different from the CVLAN TPID.
SVLAN TPIDs are configurable on a per-port basis. A service provider-side port uses the SVLAN
TPID to replace the TPID in outgoing frames' SVLAN tags and match incoming tagged frames. An
incoming frame is handled as untagged if the TPID in its outer VLAN tag is different from the SVLAN
TPID.
For example, a PE device is connected to a customer device that uses the TPID 0x8200 and to a
provider device that uses the TPID 0x9100. For correct packet processing, you must set the CVLAN
TPID and SVLAN TPID to 0x8200 and 0x9100 on the PE, respectively.
The TPID field is at the same position as the EtherType field in an untagged Ethernet frame. To
ensure correct packet type identification, do not set the TPID value to any of the values listed in
Table 15 Reserved EtherType values
Protocol type
Value
ARP 0x0806
PUP 0x0200
RARP 0x8035
IP 0x0800
IPv6 0x86DD
PPPoE 0x8863/0x8864
MPLS 0x8847/0x8848
IPX/SPX 0x8137
IS-IS 0x8000
LACP 0x8809
LLDP 0x88CC
802.1X 0x888E
802.1ag 0x8902
Cluster 0x88A7
Reserved 0xFFFD/0xFFFE/0xFFFF
Configuring the CVLAN TPID
Step
Command
Remarks
1.
Enter system view.
system-view
N/A
Summary of Contents for H3C S7500E-X
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