Which feature in Mimecast ensures protection against email spoofing?

The feature that ensures protection against email spoofing in Mimecast is the ARMed SMTP Policies. These policies leverage mechanisms like the Sender Policy Framework (SPF) and DomainKeys Identified Mail (DKIM) to authenticate incoming emails. By using these standards, Mimecast can verify whether an email originated from a legitimate sender or is forged. This helps maintain the integrity of communications, allowing only verified senders to reach recipients, thereby reducing the likelihood of successful spoofing attacks.

In contrast, policies like the Permit Sender Policy and Blocked Sender Policy mainly manage the flow of emails based on sender reputation and their inclusion or exclusion on an allowlist or blocklist rather than specifically addressing the technicalities of spoofing. While Spam Filtering focuses on detecting unsolicited bulk messages, it does not provide the same level of protection against the unauthorized use of a domain by malicious entities, which is a core factor in spoofing.