Dell Force10 E600i FTOS Version 8.4.1.5 Configuration Guide for ExaScale - Page 899

VLAN Stacking with C-Series and S-Series The default TPID for the outer VLAN tag is 0x9100. Beginning with FTOS version 8.2.1.0, both the C-Series and S-Series allow you to configure both bytes of the 2-byte TPID. Previous versions allowed you to configure the first byte only, and thus, the systems did not differentiate between TPIDs with a common first byte. For example 0x8100 and any other TPID beginning with 0x81 were treated as the same TPID, as shown in Figure 49-6. Versions 8.2.1.0 and later differentiate between 0x9100 and 0x91XY, as shown in Figure 49-8. You can configure the first eight bits of the TPID using the command vlan-stack protocol-type. The TPID on the C-Series and S-Series systems is global. Ingress frames that do not match the system TPID are treated as untagged. This rule applies for both the outer tag TPID of a double-tagged frame and the TPID of a single-tagged frame. For example, if you configure TPID 0x9100, then the system treats 0x8100 and untagged traffic the same and maps both types to the default VLAN, as shown by the frame originating from Building C in Figure 49-8. For the same traffic types, if you configure TPID 0x8100, then the system is able to differentiate between 0x8100 and untagged traffic and maps each to the appropriate VLAN, as shown by the packet originating from Building A in Figure 49-8. Therefore, a mismatched TPID results in the port not differentiating between tagged and untagged traffic. Figure 49-6. Single and Double-tag TPID Match on the C-Series and S-Series Building D VLAN BLUE Building C VLAN BLUE R1-C-Series TPID: 0x8100 TPID 0x8100 R2-C-Series TPID: 0x8100 VLAN GREEN VLAN GREEN, VLAN PURPLE VLAN PURPLE R3-C-Series TPID: 0x8100 TPID PCP (0x8100) TPID PCP (0x8100) R4-Non-Force10 System CFI (0) VID (VLAN Red) TERNET TPID: 0x8100 SERVICE PROVIDER VLAN RED Building B CFI VID TPID PCP (0) (VLAN Purple) (0x8100) CFI VID (0) (VLAN Red) VLAN RED IN Building A Service Provider Bridging | 899