Cabletron Systems FRM, User Manual

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3-8 Frame Relay Module 4. 0 User G uide, Rev 01
If LLC2 is not already configured in the FRM, configure it on the same RLP.
(Frame relay must be configured on each RLP that will use it, but LLC2 is con-
figured on one RLP only. Performance may be enhanced if both protocols are
on the same RLP, since this eliminates the need to communicate via the bus in
the FRM.)
●
Virtual LAN ID (Chapter 9), which is necessary for LLC2 functionality.
●
Physical frame relay port (Chapter 6 and Chapter 7).
●
Physical SNA port (Chapter 6 and Chapter 9). The link station SDLC/LLC2
conversion point is also defined in this record, under SNA PU Parameters.
(These parameters act as both LLC2 Originated Host and Originated Interface
records.)
●
Terminated LLC2 Host (Chapter 9), which points to the frame relay interface.
Note that the remote FRM must have an Originated LLC2 Host.
●
Frame relay terminated LLC2 Interface (Chapter 9), which defines an LLC2 ter-
mination point at the frame relay interface. Note that the remote FRM must have
an Originated LLC2 Interface.
●
SVC subscriber (Chapter 7), to route the incoming connection request from the
frame relay LLC2 Terminated Host to the SDLC port. Note that this record is
not required on the remote FRM, because that device originates the connection
(i.e., it is not being called).
Key Points
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 FRM will operate.
LLC2 Function
Internally, LLC2 connects to interfaces via a virtual bridge. 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
(Chapter 9), 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 con-
nection.
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.