Operation Manual – VLAN-VPNH3C S3100-52P Ethernet Switch Chapter 1 VLAN-VPN Configuration1-3An S3100-52P switch determines whether a received frame is VLAN tagged bycomparing its own TPID with the TPID field in the received frame. If they match, theframe is considered as a VLAN tagged frame. If not, the switch tags the frame with thedefault VLAN tag of the receiving port.By default, S3100-52P switch adopt the IEEE 802.1Q TPID value 0x8100. Somevendors, however, use other TPID values such as 0x9100. For compatibility with thesesystems, the S3100-52P switch allow you to change the TPID that a port uses whentagging a received VLAN-VPN frame as needed. When doing that, you should set thesame TPID on both the customer-side port and the service provider-side port.The TPID in an Ethernet frame has the same position with the protocol type field in aframe without a VLAN tag. To avoid problems in packet forwarding and handling, youcannot set the TPID value to any of the values in the table below.Table 1-1 Commonly used protocol type values in Ethernet framesProtocol type ValueARP 0x0806IP 0x0800MPLS 0x8847/0x8848IPX 0x8137IS-IS 0x8000LACP 0x8809802.1x 0x888E1.1.4 Inner-to-Outer Tag Priority Replicating and MappingAs shown in Figure 1-3, the user priority field is the 802.1p priority of the tag. The valueof this 3-bit field is in the range 0 to 7. By configuring inner-to-outer tag priorityreplicating or mapping for a VLAN-VPN-enabled port, you can replicate the inner tagpriority to the outer tag or assign outer tags of different priorities to packets according totheir inner tag priorities.Refer to QoS-QoS Profile part for information about priority.1.2 VLAN-VPN Configuration1.2.1 VLAN-VPN Configuration Task ListComplete the following tasks to configure VLAN-VPN:
