Which protocol should you expect to check for proper URL filtering functionality on a SonicWall firewall?

The correct choice emphasizes the importance of the HTTP protocol in relation to URL filtering on a SonicWall firewall. HTTP, or Hypertext Transfer Protocol, is the primary protocol used for transmitting web pages across the internet. Since URL filtering is designed to monitor and control web traffic based on user-defined policies, it primarily operates over HTTP.

When users attempt to access web content, their requests are sent via HTTP, making it the central point of focus for URL filtering mechanisms. By utilizing HTTP as the protocol for URL filtering, SonicWall effectively analyzes user requests against a database of allowed and blocked URLs, ensuring compliance with organizational policies.

The other protocols mentioned do not typically relate closely to URL filtering functionalities. FTP (File Transfer Protocol) is focused on transferring files rather than accessing web pages; thus, it is not the primary concern of URL filtering. BLAST is not a standard protocol used for web traffic, and SMTP (Simple Mail Transfer Protocol) is related to the sending of emails rather than web browsing. Therefore, HTTP is the most appropriate choice for checking URL filtering functionality on a SonicWall firewall.