SNA Specifications Supported


SNA Features
STREAMS Driver Features
SDLC Features
Token Ring Features
QLLC Features
Application Program Interface (API)
Terminal Emulation
Administrative Tools
TN Server Features


  • SNA support - Supports PU2 and PU2.1 with LU0 Primary, LU0 Secondary, LU2, LU7, LU6.2
  • No restrictions - Supports multiple PUs and LUs
  • Streams driver - Implemented as a STREAMS driver compatible with SVR3, SVR4, QNX and Linux
  • QLLC option - Can access NPSI hosts using QLLC
  • Hardware - Interface adapter for a total hardware/software solution
  • TN Server - Supports TN3270, TN3270E and TN5250
Gcom provides protocol solutions to connect legacy systems to TCP/IP networks. Protocols: SNA, X.25, Bisync, Frame Relay, LAPB, LAPD, HDLC, SDLC, and more. Operating systems: Windows, Linux, Unix, Solaris, Solaris Intel, QNX, and more. Hosts: Any TCP/IP/Ethernet-capable host (IBM, Unisys, Tandem, HP mainframes...), PCs, Intel PCs, SPARC or Sun workstations, and more. End-user devices: ATMs, POS, radar terminals, and more.
Streams Model

SNA Features

  • 3274/5294/5394 emulation
  • PU type 1, 2 and 2.1
  • LU type 0 Primary (host)
  • LU type 0 for low level data exchange with host
  • LU type 2 for 3270 data streams
  • LU type 7 for 5250 data streams
  • LU type 6.2
  • APPC/APPN end node support
  • TS profiles 1, 2, 3, 4 and 7
  • FM profiles 0, 2, 3, 4, 7, 18 and 19
  • Multiple PUs
  • Multiple LUs
  • XID interpretation
  • Tracing facilities

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STREAMS Driver Features

  • UNIX 5.3 or 5.4 compatible
  • QNX and Linux compatible
  • Uses AT&T's NPI protocol upstream to user or SNA API
  • Uses AT&T's DLPI protocol downstream to SDLC, LLC or QLLC
  • Management functions over control stream
  • Configuration
  • Debug trace management
  • Statistics
  • Trace buffers
  • Management data echoed to log file

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SDLC Features

  • SDLC secondary for PU2 and PU2.1
  • SDLC primary for PU2.1
  • Can emulate multiple secondaries
  • Half duplex or full duplex lines
  • NRZ or NRZI
  • Group poll response supported
  • Full duplex poll response supported
  • Switched and non-switched data circuits
  • More SDLC features

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Token Ring Features

  • Uses IBM 16/4 adapter
  • Logic link control II
  • Adapter statistics

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QLLC Features

  • Emulates SDLC secondary to SNA driver
  • Uses Gcom's 1988 compliant X.25
  • Listens for incoming calls
  • Generates outgoing calls
  • Incoming calls can be restricted to certain hosts
  • Automatically segments data using X.25 M-bit
  • Uses AT&T's DLPI protocol upstream to SNA
  • Uses AT&T's NPI protocol downstream to X.25

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Application Program Interface (API)

  • Non-blocking interface
  • Multiple sessions allowed per user process: multiple LUs and PUs
  • Complete chains exchanged between user and STREAMS driver
  • User can elect to process each chain element
  • Long RUs automatically broken into chains or segments
  • Bracket protocol supported
  • 3270 data stream API
  • 5250 data stream API
  • APPC peer to peer API
  • Error and trace logging for debug assistance
  • UNIX object code library linked in with user's program

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Terminal Emulation

  • 3278 model 2 and 5251 model 11 emulation
  • Uses termcap/terminfo and curses for portability
  • Up to 254 terminal sessions
  • Can be used over a LAN, WAN or asynchronous dialup
  • UNIX user program run from shell prompt
  • TN3270 client/server
  • TN5250 client/server

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Administrative Tools

  • Line analysis/statistics
  • PU analysis/statistics
  • LU analysis/statistics
  • Troubleshooting
  • Configuration

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TN Server Features

  • Supports TN3270E, TN3270, TN5250 clients and 3270 and 5250 hosts
  • Can associate printer LU with application LU
  • Accessible to specific PU/LU combinations
  • Accessible to TCP/IP network across any media supported by machine ­
    Ethernet, Token Ring, and Frame Relay

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