Introduction - Digi PortServer/8 User Manual

Introduction

The Digi PortServer intelligent terminal server gives you the ability to
connect up to 16 RS-232 asynchronous serial devices (such as terminals
and printers) to an Ethernet network. Both Twisted Pair (10BaseT) and
Thinnet (10base2) cabling standards are supported via the appropriate
connectors on the side of the PortServer box.
The PortServer hardware features a 20 MHz 80186 microprocessor and
a 83902 16-bit network interface controller. Other features include one
megabyte of RAM, 256K of ROM, up to 8k x 8 of EEPROM, and
16c554 UARTs. Self-tests on power-up help ensure reliability. Front-
panel LEDs and controls can be used for diagnostic testing and per-
formance checks, monitoring either RS-232 or Ethernet activity.
Operating software is in firmware, but can also be downloaded from a
connected server or workstation via TFTP (Trivial File Transfer Proto-
col), meaning that the PortServer operating system can always have the
most current software without changing the firmware.
After the power-up self-tests and loading of the operating software
(either from firmware or downloaded), the PortServer software sends
login messages to all connected terminals. (Ports set up as printers or
modems do not receive login messages; the factory default sets all ports
as terminals.)
When they get the login prompt, users can log in to the PortServer's
on-board operating system. Depending upon their privilege level (as
defined by the system administrator), commands can now be issued to
the PortServer software to change parameters or connect to one of the
network systems. The PortServer software allows the system admini-
strator to set up password-protected accounts with various privilege
levels to limit certain users or terminals to restricted access to systems
on the network.
Description
Operation
Overview
PortServer Terminal Server Ÿ Page 1