Client sends RTSP OPTIONS requests to check supported methods and confirm that an RTSP service is exposed, then disconnects without attempting authentication or stream setup. This pattern is typically associated with automated reconnaissance or internet-wide scanning rather than active stream access.

FTP session where the client upgrades to TLS (AUTH TLS) and proceeds to request server capability information using FEAT, HELP, and SYST before cleanly terminating the session. This pattern indicates structured service and feature enumeration rather than file interaction. The sequence is consistent with automated reconnaissance used to fingerprint FTP server configuration, supported extensions, and implementation details

Automated SMTP interaction performing a minimal capability check by issuing EHLO followed by a STARTTLS upgrade request and immediately terminating the session. This pattern is commonly associated with internet-wide scanners, security research crawlers, or opportunistic bots verifying whether an SMTP service supports encrypted communication. The absence of authentication attempts or message submission indicates reconnaissance or service fingerprinting rather than active abuse.

Client performs a modern MongoDB handshake using the hello command followed by a buildinfo request to gather server capabilities and version details. This sequence is commonly associated with automated fingerprinting or discovery activity against exposed MongoDB instances rather than normal application queries.