The TLS variant of e-Watch's SiteWatch video-surveillance server port; 3765 is the cleartext one.
IANA registers TCP 3766 to e-Watch Corporation as sitewatch-s, the SSL form of the SiteWatch server that sits on 3765, with UDP 3766 marked Reserved; the entry was last updated in 2014. SiteWatch is a commercial video-surveillance product, and the protocol is proprietary and undocumented publicly. Outside deployments of that specific product you will not encounter this port.
Expose with care
A surveillance server reachable from the internet is a camera-feed exposure risk; TLS on the transport does not substitute for putting it behind a VPN.
$ openssl s_client -connect TARGET:3766 -brief </dev/nullSeen this on your network? Beige Box scans your Wi-Fi and shows every open port on every device — and its Ports tool links straight back here.
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