Alcatel Carrier Internetworking Solutions Omni Switch/Router - Manual (Page 537)

Translational Bridging
Page 18-41
Translational Bridging
Translational Bridging enables internetworking between FDDI, Ethernet, and Token Ring
LANs. There is no standard which encompasses this. The Omni Switch/Router’s features
focus on bridging of frames between media and translating the MAC and LLC headers into the
appropriate “native” frame formats. This provides media-independent internetworking.
Learning
For VLAN trunk frames, the switch will learn the source MAC address of the encapsulated
frame and associate this with the source MAC address of the originating switch. When a frame
arrives, the switch checks to see if the frame has been learned. If so, then the frame will be
encapsulated and sent directly to the destination switch. If not, then the switch will learn the
association of VLAN, trunk service, virtual port, source, and destination MACs. If the switch
has no ports in the VLAN associated with the frame’s destination, the frame is dropped.
Translations across Trunks
The Omni Switch/Router sends frames onto the trunk in the same format as the original LAN
type. Any required translation is done at the destination switch.