Theory Of Operation; Setup And Addressing; Protocols - Contemporary Controls Metasys JC-MER-CXB User Manual

The JC-MER-CXB program is accessed via COM2. The embedded
operating system is accessed via COM1. If a terminal emulation
program is attached to COM2, real-time routing statistics can be
observed. But once the router is started, no such cable connection is
required for continued operation.

Theory of Operation

Setup and Addressing

The method of linking the two networks is to separate the N1 LAN
into a number of ARCNET subnets. (In this document, the terms
"subnet" and "ARCNET segment" are the same.) Each ARCNET
subnet then connects to the customer's Ethernet network via a single
JC-MER-CXB.
The router uses the N1 network addressing scheme to route messages
among the various ARCNET segments. Dividing Metasys into
multiple subnets has no affect on existing Ethernet communications,
and again, remains transparent to the operator.
To the operator, the router is simple to use and maintain. Once it is
configured to the customer's network, the router works on its own,
uninterrupted. Branch office personnel configure the unit (via
HyperTerminal) by accessing a single screen. Once set, the data is
saved to a flash disk. Upon power up, the program and configuration
data is executed without any intervention. There are no moving
storage devices on the unit.

Protocols

The JC-MER-CXB uses the UDP/IP communications protocol to
transmit messages across the Ethernet network. This is important
because it allows the router to easily integrate into existing customer
networks that comprise multiple Internet (TCP/IP protocol suite)
networks.
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