us01sip804.iad.zoom.us is a subdomain belonging to Zoom Video Communications. Unlike a customer-facing website, this is an internal technical endpoint — specifically a SIP server used for Zoom's video conferencing infrastructure. So the usual expectations around contact pages, privacy policies, and social media presence simply don't apply here.
What does matter for this type of site is security and ownership. On both fronts, the signals are solid. The SSL certificate is valid, issued by DigiCert, and no threats have been flagged by Google Web Risk or any blacklist. Ownership is clearly tied to Zoom, one of the largest video communication companies in the world.
If you're asking “is us01sip804.iad.zoom.us a scam?” — no, it's not. It's a legitimate part of Zoom's network. Whether you're a sysadmin troubleshooting a connection or a user seeing this address in a log, there's no reason to be concerned. Just don't expect a pretty homepage; this site deliberately blocks browser access with a 403 Forbidden, which is standard for internal systems.