NPort IA5000A Series
Choosing the Proper Operation Mode
4-4
UDP Mode
Compared to TCP communication, UDP is faster and more
efficient. In UDP mode, you can not only unicast but also
multicast data from the serial device to multiple host
computers, and the serial device can also receive data
from multiple host computers, making this mode ideal for
message display applications.
Pair Connection Mode
Pair Connection Mode employs two NPort IA5000A units in tandem, and can be used to remove the 15-meter
distance limitation imposed by the RS-232 interface. One NPort IA5000A is connected from its RS-232 port to
the COM port of a PC or other type of computer, such as a hand-held PDA, and the serial device is connected
to the RS-232 port of the other NPort IA5000A. The two NPort IA5000A units are then connected to each other
with a cross-over Ethernet cable, both are connected to the same LAN, or in a more advanced setup, they
communicate with each other over a WAN (i.e., through one or more routers). Pair Connection Mode
transparently transfers both data and modem control signals (although it cannot transmit the DCD signal)
between the two NPort device servers.
Ethernet Modem Mode
Ethernet Modem Mode is designed for use with legacy operating systems, such as MS-DOS, that do not support
TCP/IP Ethernet. By connecting one of the NPort IA5000A’s serial port to the MS-DOS computer’s serial port,
it is possible to use legacy software originally designed to transmit data via modem, but now transmit the data
over the Ethernet.