CIC uses certain IP addresses to send data to and receive data from your trading partners and customers. If you use an IP allowed list (also called a "whitelist"), be sure to include the following to allow CIC access to your system:
Using a Subnet Mask
If your network requires a subnet mask and you use individual IP addresses, the subnet mask is 255.255.255.255. If you use the range of IP addresses, the subnet mask is 255.255.255.0.