Alcatel Carrier Internetworking Solutions Omni Switch/Router - Manual (Page 518)

The User Interface
Page 18-22
ATM LANE - SNAP Mode
All IPX frames are translated to SNAP unless they are already
SNAP, in which case they are forwarded as is.
All Ethertype or SNAP frames from Ethernet and SNAP frames
from Token Ring or FDDI are translated to SNAP or left as SNAP.
The exception is Banyan Vines frames from FDDI, which are
translated to Ethertype.
All other LLC frames are left as is. The exception is Banyan Vines
from Token Ring, which is translated to Ethertype.