Description: This solution addresses upcoming Authorize.Net domains and IP addresses updates
Authorize.Net domains and IP addresses are schedule to be updated in early 2019. This will not affect the Connectors because we use URLs with fully qualified domain names. There may, however, be an affect if there is a firewall set up by individual organizations to restrict it by IP address.
Please seen the article from Authorize.net contain the details of the the changes. https://support.authorize.net/s/article/Authorize-Net-Domains-and-IP-Addresses