Cabletron Systems 1800 - Manual (Page 42)

3-6 SmartSwitch 1800 4. 0 User G uide, Rev 01
For reference, the following table describes what happens to a MAC address at the
SmartSwitch 1800 if the sending and receiving formats are different.
LAN IDs
LAN IDs can be configured in two places:
●
LLC2 node defaults, to identify a virtual bridge that connects the LLC2 function
to LAN interfaces.
●
LLC2 frame relay interfaces using 802.5 Source Route Bridge format, to
identify the ring number used by a source-route bridge at the remote end. (This
ID is normally assigned by a system administrator.) Note that the LAN ID on an
originated LLC2 interface must match the LAN ID on the corresponding termi-
nated interface.
Be aware that when configuring these records, LAN IDs must be entered in hex. Also
note that, other than the matching IDs on each originated/terminated interface pair,
each LAN ID must be unique within the network on which the SmartSwitch 1800 will
operate.
LLC2 Function
Internally, LLC2 connects to interfaces via the Bridge protocol. LLC2 Host and
Interface records act as both origination and termination points for LLC2. For
example, if you are configuring SDLC-to-LLC2 conversion to be transmitted over
frame relay to a Token Ring host, the following is the logical LLC2 record flow: SNA
Port/PU record (
page 9-4 ), with the parameter LLC2 Connection set to Yes . (This acts
as the both the LLC2 Host and LLC2 Interface termination record). In addition, you
must configure an originated Host for the target MAC address, and an interface for the
physical connection.
Terminated LLC Host records always make the calls. Originated LLC Host records
always expect to receive calls.
Only one Originated and one Terminated LLC Host record can be configured for each
MAC address.
Table 3-1 MAC Address Conversion
Received from: Forwarded to: Action taken:
802.3 802.5 Converts MAC header to LAN header (including cached
RIF), and bit-swaps address
802.3 Native LLC2 Drops MAC header
802.5 802.3 Coverts LAN header to MAC header, and bit-swaps address
802.5 Native LLC2 Drops LAN header
Native LLC2 802.3 Adds MAC header
Native LLC2 802.5 Adds LAN header (including cached RIF)