Configuring FDDI VLAN Characteristics

An FDDI VLAN represents a single logical ring with one ring number.

Note: Before you start, review the VLAN configuration rules.

Note: This switch only supports Ethernet interfaces. You configure FDDI media-specific characteristics only for VLAN Trunk Protocol (VTP) global advertisements to other switches.

To configure FDDI-specific VLAN characteristics:

  1. In the VLAN ID field, enter the number of the FDDI VLAN.
  2. In the VLAN Name field, enter a VLAN name from 1 to 32 characters that is unique within the administrative domain.
    The default name is "VLANxxxx" where "xxxx" represents four digits (including leading zeros) equal to the VLAN ID number.
  3. Select FDDI from the VLAN Media Type drop-down list.
    If you are changing an existing VLAN, the media type is already selected.
  4. In the 802.10 SAID (security association identifier) field, enter a number from 1 to 4294967294 that is unique within the administrative domain.
    The default is 100000 plus the VLAN ID.
  5. In the MTU Size field, enter a number from 1500 to 18190 for the maximum transmission unit (packet size in bytes) that the VLAN can use.
    The default is 1500.
  6. If you are translationally bridging from one VLAN type to another (such as from FDDI to Ethernet), in the Translational Bridge 1 and Translational Bridge 2 fields, enter the VLAN IDs (from 0 to 1005) of the two VLANs to which this VLAN is translationally bridging.
    Note:     By default, these fields are set to zero, which means translational bridging is not in effect.
  7. In the VLAN Status drop-down list, select Active.
    By default, Suspended is selected. When the status is suspended, all traffic for that VLAN is blocked on all switches in the management domain.
  8. In the Ring Number field, enter a logical ring number from 1 to 4095.
    The ring number is used for source routing. No default ring number is defined, and you must specify one.
  9. In the Parent VLAN field, enter a parent VLAN ID number from 0 to 1005.
    Note: By default, this field is set to zero, which means no parent VLAN is defined.
    The parent VLAN of an FDDI VLAN must be an FDDI-NET VLAN, which represents a set of ring segments connected by source-route bridges. The parent VLAN is the VLAN ID to which the FDDI VLAN is attached for source routing functions.
  10. Click OK to put your changes in effect and close the VLAN Configuration dialog box.
    If you created a new VLAN, the new VLAN is displayed on the VLAN Configuration tab.
  11. Click OK to close the VTP Management window.