Some corporate environments are behind strict firewall rules, where access to cloud services needs to be exclusively granted. While the easiest way to allow access to ISL Online servers is making a DNS exception for "*.islonline.net" (outgoing TCP ports 7615, 443, 80), some firewalls support only IP based exceptions. In such cases, network administrators must resort to adding rules for each ISL Online server from the list.
Adding exceptions and maintaining such list of ISL Online servers represents a lot of tedious work. New servers are added to the ISL Online production range, old ones are decommissioned, IP's change, which forces network administrators to regularly update their set of network security rules.