Servers www-1, www-2 and www-4 to be accessible from UIC proxy server

To improve the security of our web infrastructure, starting July 9, servers www-1, www-2, and www-4 will be accessible via http and https from UIC only. The servers will still be accessible via the proxy server www-proxy-prod. There will be no downtime with this change. Users will not need to take action, and services will not be affected.