Certified Internet Web (CIW) Professional Practice Exam 2025 – Complete All-in-One Guide to Exam Success!

The recommended email protocol for sending emails that include large attachments securely is SMTP, which stands for Simple Mail Transfer Protocol. SMTP is specifically designed for sending emails across networks, and it efficiently handles the transfer of messages, including those with large attachments.

When sending emails, SMTP takes the message and any associated data, such as attachments, and delivers it to the recipient's email server. It can support large files as long as the server and recipient's email client are configured to handle those sizes. Additionally, SMTP can work in conjunction with encryption methods such as TLS (Transport Layer Security) to ensure that the contents of the email, including attachments, are transmitted securely over the internet.

In contrast, protocols like FTP (File Transfer Protocol) are primarily used for transferring files between systems, not for sending email. IMAP (Internet Message Access Protocol) is used for retrieving and storing emails, not for sending them, while HTTPS (Hypertext Transfer Protocol Secure) is used for secure web browsing rather than email transmission. Thus, SMTP stands out as the appropriate choice for sending emails with large attachments securely.