What is 0x8100 EtherType?
0x8100 is standard ethertype for single tagged frames (802.1Q), it can be used(and it is) for QinQ tunneling but you should be careful with other vendors configuration, as defaults vary.
What is the EtherType of an IEEE 802.1Q frame?
802.1Q VLAN tagging uses an 0x8100 EtherType value. The payload following includes a 16-bit tag control identifier (TCI) followed by an Ethernet frame beginning with a second (original) EtherType field for consumption by end stations. IEEE 802.1ad extends this tagging with further nested EtherType and TCI pairs.
What is QinQ used for?
The general purpose of QinQ is to allow frames from multiple customers to be forwarded (or tunneled) through another topology (provider network) using service VLANs or S-VLANs.
What is Dot1q tunneling EtherType?
802.1Q tunneling enables service providers to use a single VLAN to support customers who have multiple VLANs, while preserving customer VLAN IDs and keeping traffic in different customer VLANs segregated. A port configured to support 802.1Q tunneling is called a tunnel port.
How does IEEE 802.1 Q tag frames?
IEEE 802.1Q uses an internal tagging mechanism which inserts a 4-byte tag field in the original Ethernet frame between the Source Address and Type-Length fields. Because the frame is altered, the trunking device recomputes the FCS on the modified frame. 802.1Q does not encapsulate the original frame.
What is Cvlan and Svlan?
CVLAN tag—Identifies the VLAN to which the frame belongs when it is transmitted in the customer network. SVLAN tag—Identifies the VLAN to which the QinQ frame belongs when it is transmitted in the service provider network. The service provider allocates the SVLAN tag to the customer.
What is Tpid in networking?
Another two-byte field, the Tag Protocol Identifier (TPI or TPID), precedes the VLAN tag field. Two fields were necessary to hold one piece of information, the VLAN tag, to enable receivers to distinguish between untagged or plain Ethernet frames and those containing VLAN tags.
What is dot1q tunneling?
802.1Q tunneling enables Service Providers to use a single VLAN to support customers who have multiple VLANs, while preserving customer VLAN IDs and keeping traffic in different customer VLANs segregated. A port configured to support 802.1Q tunneling is called a tunnel port.
What is EtherType 0x88a8 and 0x9100 used for?
The EtherTypes you mention (0x88a8 and 0x9100) are registered. The EtherType of 0x88a8 is registered, and it is used by Provider Bridging (IEEE 802.1AD) & Shortest Path Bridging (IEEE 802.1AQ). The EtherType of 0x9100 is registered, and it is used for VLAN-tagged (IEEE 802.1Q) frames with double tagging.
What is the default VLAN EtherType TPID for QinQ?
VLAN Ethertype Config Tests ¶ 142.1. Description ¶ for single vlan default TPID is 0x8100. for QinQ, default S-Tag+C-Tag VLAN TPIDs 0x88A8 + 0x8100. This feature implemented configuration of VLAN ethertype TPID, such as changing single vlan TPID 0x8100 to 0xA100, or changing QinQ “0x88A8 + 0x8100” to “0x9100+0xA100” or “0x8100+0x8100”
How do I remove the VLAN tag identifier 16 on Port 0?
Send 1 packet with VLAN TPID 0xA100 and VLAN Tag 16 on port A , Verify that the VLAN packet can be received in port B and TPID is 0xA100 Remove the VLAN Tag Identifier 16 on port 0: Send 1 packet with VLAN TPID 0xA100 and VLAN Tag 16 on port A , Verify that the VLAN packet cannot be received in port B.
What is the default EtherType for the Q-in-Q outer tag?
Currently, the default ether type is 0x8100 on a Cisco 7600 for the Q-in-Q outer tag. However, a few non-Cisco vendors use 0x9100 or 0x9200 ether type for the Q-in-Q outer tag. For Cisco 7600 router to operate seamlessly with other vendors it is required to provide a mechanism to change the default ethertype.