2: Introduction
IP Address Every device connected to an IP network must have a unique IP address. This address is
used to reference the specific unit. The Micro125 is automatically assigned an IP addres s on
DHCP-enabled networks, as it is DHCP-enabled by default.
Port Numbers Every TCP connection and every UDP datagram is defined by a destination I P address and a
port number. For example, a Telnet application commonly uses port num ber 23. A port
number is similar to an extension on a phone system.
The unit's serial channel (port) can be associated with a specific TCP/UDP port number. Port
number 9999 is reserved for access to the unit's Setup (configuration) Mode window. Por ts 0-
1024 are reserved as well. For more information on reserved port num bers, see Table 8-5.
Reserved Port Numbers.
Micro125 User Guide 11