Omron CS1W-ETN21 - Manual (Page 132)

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Private and Global Addresses Section 5-3
5-2-5 Pairing IP Addresses and FINS Node Addresses
The following table shows the methods for pairing IP address and FINS node
addresses, and the relation between fixed and variable address, for both
FINS/UDP and FINS/TCP.
5-3 Private and Global Addresses
5-3-1 Private and Global Addresses
There are two kinds of IP addresses, private and global.
• Global addresses: These are IP addresses that connect directly to the
Internet. Allocated by application to NIC, each
address is unique in the world, and as many as 4.3
million can be allocated worldwide.
• Private addresses: These are IP addresses for Intranet (LAN) use, and
cannot connect directly to the Internet. Frames that
include private IP addresses are restricted by the
router from being sent outside the LAN.
Generally, as shown below, global addresses in the intranet are allocated only
to IP routers (such as broadband routers) interfacing with the Internet. All
other nodes in the intranet, including the Ethernet Unit, are allocated private
addresses.
Programmable Terminal NS Series No: Set manually. FINS
communications are not
possible with personal
computers set automati-
cally by DHCP.
Open Network Controller (ONC) ---
Product Model/Series/
Version
Supports combined
method?
Communi-
cations
method
Method of pairing
of IP addresses
and FINS node
addresses
IP address determination Client (personal
computer of PLC)
Server (PLC)
FINS node
address
IP address FINS node
address
IP address
FINS/UDP By pairing FINS
node addresses with
IP addresses in
Ethernet IP address
conversion Automatic gen-
eration method
(static) Fixed Fixed Fixed Fixed
Automatic gen-
eration method
(dynamic) Fixed Fixed or
variable Fixed Fixed
IP address table
method Fixed Fixed or
variable Fixed Fixed
Combined
method Fixed Fixed or
variable Fixed Fixed
FINS/TCP By automatic conver-
sion of FINS node
addresses at Ether-
net Unit and remote
node (and then
sending and receiv-
ing data) Automatic Connection
method (auto-
matic FINS
node address
conversion) Fixed or
can be allo-
cated auto-
matically
when not
determined. Fixed or
variable Fixed Fixed