Which three SIP headers should be overwritten with a SIP domain in a Topology Hiding...

When configuring a Topology Hiding Profile associated with a Session Manager in a typical Avaya Session Border Controller for Enterprise (ASBCE) deployment, you should overwrite the following three SIP headers with a SIP domain: From, Refer-To, and To. A Topology Hiding Profile is a configuration object that masks the FQDN or IP address portion of SIP headers to hide the internal topology of the network. For example, SBCE@avaya.com can become SBCE@135.122.18.7, or just the opposite. The From header indicates the identity of the originator of a SIP request or response. The Refer-To header indicates the identity of the recipient of a REFER request, which is used to transfer calls or sessions. The To header indicates the identity of the intended recipient of a SIP request or response. These headers should be overwritten with a SIP domain to prevent exposing internal FQDNs or IP addresses to external entities