Is it possible for you to get a private/direct connect service from your network perimeter to the cloud provider and eliminate using the public connectivity? Or because its Internet-based you have to use public connectivity? James W. Breeden Managing Partner Arenal Group: Arenal Consulting Group | Acilis Telecom | Pines Media PO Box 1063 | Smithville, TX 78957 Email: james@arenalgroup.co | office 512.360.0000 | www.arenalgroup.co -----Original Message----- From: NANOG [mailto:nanog-bounces@nanog.org] On Behalf Of Torres, Matt Sent: Thursday, May 4, 2017 7:47 AM To: nanog@nanog.org Subject: Ingress filtering from an external cloud service to the internal network NANOG, We have a hybrid cloud model that includes an external cloud service that needs to reach back into our internal network. The application documentation states that this connection cannot go through a proxy server. I am not in a position to redesign this solution or change the parameters. My question to NANOG is how to manage (filter/secure) the ingress traffic from the external cloud service. Past network guy managed inbound firewall rules based on the cloud-providers source IP address, but this wasn't sustainable and led to multiple outages as the external (source) IP has changed from time to time. I can define the destination ports well enough, but not the source IP addresses. Any ideas on how I can filter this type of inbound traffic from an internet-based service? Thanks Matt