What type of scanning is likely occurring if an outsider is trying to connect using TCP on port 22?

The scenario presented involves an outsider attempting to connect using TCP on port 22. This port is conventionally associated with the SSH (Secure Shell) protocol, which is used for securely accessing networked systems over an unsecured network.

SSH operates on port 22, making it the target for any connectivity attempts by external entities looking to establish remote access to a device or server. Knowledge of port assignments is critical in the field of cybersecurity, as it helps in identifying the nature of the traffic and the protocols in use.

In this case, since the connection attempt is specifically on port 22, it indicates that the scanning activity is focused on assessing whether SSH services are available and potentially exploitable on the targeted device. This type of scanning is particularly significant as it could be a precursor to attempts at unauthorized access if the SSH service is weak or misconfigured.

The other options involve different protocols that utilize entirely different ports. FTP typically uses port 21, Telnet uses port 23, and HTTP traditionally operates on port 80. Therefore, identifying the scanning type based on the specified port number is critical for understanding the intention behind the scanning activity.