Private And Global Addresses - Omron CJ1W-EIP21 Operation Manuals

4 Determining IP Addresses
4-3

Private and Global Addresses

4-3-1

Private and Global Addresses

There are two kinds of IP addresses, private and global.
IP address
Global address
Private address
Generally, as shown below, global addresses in the intranet are allocated only to IP routers (such as
broadband routers) interfaced with the Internet. All other nodes in the intranet, which includes the Eth-
erNet/IP Unit, are allocated private addresses.
● Intranet
Global address
IP router
Private address
Firewall
4-10
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 billion can be allocated world-
wide.
These are IP addresses for Intranet (LAN) use. Direct con-
nection to the Internet is not possible. Frames that include
private IP addresses are restricted by the router from being
sent outside the LAN.
● Intranet
Personal computer
(e.g., Sysmac Studio)
Firewall
IP router
Private address
● Internet
Global address
Ethernet (EtherNet/IP)
Controller
Private address
Private address
CJ-series EtherNet/IP Units Operation Manual for NJ-series CPU Unit (W495)
Description
Ethernet (EtherNet/IP)
Controller
Private address
Cannot connect to Internet
(required)
Cannot connect to Internet
Private address
Personal computer
(e.g., Sysmac Studio)
Controller