In looking at my firewall logs recently, I have noticed a number of connections that I am puzzled about. We have an Exchange 2010 server behind our firewall. We also have an email gateway behind our firewall, so all incoming email is directed to the gateway device on port 25 and then forwarded to the Exchange server when appropriate. On the firewall, I have outbound port 25 enabled from our Exchange server to any, and inbound port 443 enabled to the Exchange server to allow access to OWA. We have a relatively large number of devices (smart phones, tablets, etc, as well as persons with laptops connecting Outlook to Exchange via https) that connect to the mailboxes on the server. In looking at the firewall logs for all blocked outbound connections, I am seeing a relatively large number of connection attempts from our Exchange server to outside addresses. The source port is always 443, and the destination port varies. When I investigate the destination addresses, most of them are typically servers associated with wireless carriers (ie: servers in the myvzw.com domain). I am thinking that these connections are somehow related to the connections made to the Exchange server from the devices on wireless networks, but I don't recall seeing these in the logs before and am trying to get a read on what they may be. Please let me know if you have any information on what might be causing these. I am not seeing any other odd behavior and the public IP of our Exchange server is not bl listed. Thanks in advance for thoughts on what might be causing this.