EZT-570S User Manual
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9.3 Ethernet
Communications
The EZT-570S provides two forms of Ethernet communication interfaces for monitoring and
controlling the chamber across a network. The web server interface provides a monitor only interface
while the VNC server interface allows a user to manipulate and control the chamber remotely by
viewing the EZT-570S display directly on their PC screen.
In order to use Ethernet communications, the EZT-570S must be properly connected to a
network. To connect the EZT-570S to a network, connect the chamber’s Ethernet port to
your network using a standard CAT5 cable connection. After connecting the network cable, it
may be necessary to cycle power to the EZT-570S in order for it to obtain a valid IP address
from your network.
9.3.1
Guidelines of Smart Networking Practice
The expansion of Ethernet onto the industrial floor has brought forth a new realm of possibilities from
the gathering of information to the inherent control of equipment from anywhere around the world.
The flexibility and convenience that this provides makes it a very desirable feature for new equipment.
The EZT-570S provides this ability, but there are considerations that must be taken by the end user
to protect their equipment and investment.
Just like placing a personal computer on the internet opens it up to outside attack, placing your
chamber on a network poses the same risk. The first thing to remember is this: The most likely cause
of problems is not a hacker trying to sabotage your equipment, but more often to be related to the
ubiquity of PCs with Ethernet cards, the ease with which your own co-workers can ‘hang stuff on the
network,’ and careless or nonexistent internal security measures. Accidental problems are more
common than deliberate ones.
Allowing anyone access to the EZT-570S by placing it on the office LAN, also opens the door for
accidental shutdown, damage to equipment, loss of data, lost time, etc. This is possible even by the
most well-intentioned co-workers. Thus, there are several steps that should be taken to minimize this
risk.
The first is to never mix your office LAN with your control LAN. The control LAN should be a separate
network that consists of your environmental chamber(s) and possibly any other equipment that you
may have that is related to the operation of the system. It should be separated from your office LAN
by a firewall, or at minimum, a bridge or router. A control network and a business network have two
entirely different purposes and their interaction should be closely controlled.
It is also unwise to assume that any Ethernet capable devices themselves have any security features
at all. The EZT-570S VNC server only provides minimal single-password based security access.
Separating the control LAN from the office LAN using a firewall would increase security and only
allow control access that is based on a combination of IP source address, destination address, and
port number. This is by no means completely ‘hacker-proof,’ but it should keep the well-meaning co-
workers out.
Another hazard is connecting consumer ‘plug and play’ devices to your control LAN. A printer for
example, might flood the network with traffic in a ‘broadcast storm’ as it tries to self-configure or
advertise its presence to all nodes on the network. Faulty devices, for example defective NIC cards,
can transmit large amounts of bad packets (i.e., runts, which are abnormally short Ethernet frames)
into your network. Using switches instead of hubs will limit the effect of such problems.
Summary of Contents for EZT-570S
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