Cabletron Systems 1800 - Manual (Page 127)

Chapter 9
Configuring SNA
Introduction
SNA support in the SmartSwitch 1800 includes SDLC for serial lines and LLC2 for
LAN connections. 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 SmartSwitch 1800 SNA ports can also communicate with any
QLLC-compatible devices that have integral X.25 interfaces (e.g., NPSI on IBM
3725/3745).
SDLC support includes:
●
Configurable frame size
●
Configurable link addresses
●
NRZ/NRZI support
●
Compatible with QLLC/NPSI
●
HPAD (PU 2.1, 4.0), TPAD (PU 1.0, 2.0, 2.1), NPAD, and XPAD (transparent)
modes
●
Point-to-point and multipoint configurations
●
SDLC-to-LLC2 and LLC2-to-SDLC conversion
●
Autocall
●
Request to Send (RTS) support
LLC2 support includes:
●
Supports both ends of PU2-to-PU2, PU2.1-to-PU2.1, and PU4-to-PU4 connec-
tions
●
End-to-end compatibility with SNA/APPN devices over LANs
●
Compatibility over frame relay network with IBM FEP with NCP 7.1 and above
●
MAC-level virtual addressing
●
Token ring, Ethernet, or frame relay interface
●
SDLC-to-LLC2 and LLC2-to-SDLC conversion
●
RFC1490 encapsulation in native LLC2, 802.3, or 802.5 format
●
QLLC/NPSI compatibility