Cabletron Systems FRM User Manual - Chapter 9
Chapter 9
Configuring SNA
Introduction
SNA support in the FRM includes SDLC for serial lines and LLC2 for LAN connec-
tions. SNA ports are used to connect IBM hosts with PUs (physical units), over a
frame relay (via RFC1490) or X.25 (via Annex G) network. SDLC-to-LLC2 and
LLC2-to-SDLC conversion are performed for transmission over frame relay.
Devices attached to FRM SNA ports can also communicate with any QLLC-com-
patible devices that have integral X.25 interfaces (e.g., NPSI on IBM 3725/3745).
SDLC support includes:
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Configurable frame size
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Configurable link addresses
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Two-way simultaneous transmission
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NRZ/NRZI support
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Compatible with QLLC/NPSI
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HPAD (PU 2.1, 4.0), TPAD (PU 1.0, 2.0, 2.1), NPAD, and XPAD (transparent)
modes
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Point-to-point and multipoint configurations
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SDLC-to-LLC2 and LLC2-to-SDLC conversion
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Autocall
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Request to Send (RTS) support
LLC2 support includes:
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Supports both ends of PU2-to-PU2, PU2.1-to-PU2.1, and PU4-to-PU4 connec-
tions
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End-to-end compatibility with SNA/APPN devices over LANs
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Compatibility over frame relay network with IBM FEP with NCP 7.1 and above
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MAC-level virtual addressing
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Token ring, Ethernet, or frame relay interface
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SDLC-to-LLC2 and LLC2-to-SDLC conversion
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RFC1490 encapsulation in native LLC2, 802.3, or 802.5 format
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QLLC/NPSI compatibility