Registered as "Multiling HTTP" with no public specification and effectively no deployment.
IANA assigns 777 to "multiling-http", registered by Alejandro Bonet. No RFC, vendor documentation, or open-source implementation of the protocol was ever published, so nothing is known about it beyond the registry entry. Nothing in common use listens here. A memorable number like 777 is more often picked by hand for an internal HTTP service or a proxy than used for its registration.
Expose with care
Judge by the service you actually fingerprint; the registration carries no security properties worth reasoning about.
$ nmap -sV -p 777 TARGETSeen 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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