int fddi 2/0.1 ip address 172.16.1.1 255.255.255.0 encapsulation sde 100 int fddi 2/0.2 ip address 172.16.2.1 255.255.255.0 encapsulation sde 200
The configuration applies to FDDI subinterfaces. Each VLAN must be configured on a subinterface and should support a single subnetwork. The encapsulation sde 100 statement under subinterface 2/0.1 enables 802.10 encapsulation and associates VLAN 100 with the interface, whereas the statement encapsulation sde 200 associates VLAN 200 with subinterface 2/0.2.
Figure 8-11 illustrates 802.10 encapsulation. The 802.10 header contains the MAC header, a Clear header, and a Protected header. The MAC header contains the usual 48-bit destination and source MAC addresses found in FDDI, Ethernet, and Token Ring networks. The Clear and Protected headers, however, are additions from the 802.10 standard. The Protected header duplicates the source MAC address to ensure that a station is not spoofing the real source. If the source address in the MAC and Protected headers differ, another station took over the session.
Was this article helpful?