User's Manual

NE-4100 Series User’s Manual Choosing the Proper Operation Mode
4-2
Overview
WE-2100T Series Embedded Wireless Network Enablers act as a bridge to connect your serial
devices to the wireless LAN. The built-in TCP/IP stack saves you a lot of time on programming
networking protocols. One simple step allows you to choose the proper operating mode, and then
use your computer to access, manage, and configure your serial device over the Internet from
anywhere in the world.
Traditional SCADA and data collection systems rely on serial ports (RS-232/422/485) to collect
data from various kinds of instruments. Since WE-2100T is equipped with the ability to convert
between serial and Ethernet signals, your SCADA and data collection system will be able to
access all devices connected to a standard TCP/IP network, regardless of whether the devices are
used locally or at a remote site.
Three different socket modes—TCP Server, TCP Client, and UDP Server/Client—, one real COM
and RFC-2217 modes are available. The main difference between the TCP and UDP protocols is
that TCP guarantees delivery of data by requiring the recipient to send an acknowledgement to the
sender. UDP does not require this type of verification, making it possible to offer speedier
delivery. UDP also allows multicasting of data to groups of IP addresses.
TCP Server Mode
In TCP Server mode, WE-2100T provides a unique
IP:Port address on a TCP/IP network. WE-2100T wait
passively to be contacted by the host computer, allowing
the host computer to establish a connection with and get
data from the serial device. This operation mode also
supports up to 8 simultaneous connections, so that
multiple hosts can collect data from the same serial
device—at the same time.
As illustrated in the figure, data transmission proceeds
as follows:
1. The host connects to the WE-2100T configured for
TCP Server Mode.
2. Once the connection is established, data can be
transmitted in both directions—from the host to the
WE-2100, and from the WE-4100T to the host.