Sender Filtering (Email Reputation and IP Profiler)

When Cloud Pre-Filter filters messages for all your domains:

Cloud Pre-Filter uses Email Reputation to filter all messages before they reach your network. This makes using Sender Filtering (Email Reputation and IP Profiler) redundant.

When Cloud Pre-Filter filters messages for some of your domains:

Cloud Pre-Filter is not using Email Reputation to scan all messages before they reach your network. The messages from domains that are not routed through Cloud Pre-Filter may still be malicious.

Spam Prevention Solution (SPS)

IMSVA should always use SPS, which means antispam policies should still be created.

Cloud Pre-Filter uses a very conservative approach to detect spam. Cloud Pre-Filter does this to lower the risk that a legitimate message is detected as spam.

Using antispam policies on IMSVA will further reduce the spam reaching your email recipients.

Trend Micro Antivirus and Content Filter

IMSVA should always use the Antivirus and Content Filter, which means antivirus policies and content filtering policies should still be created.

Cloud Pre-Filter does not support content filtering of messages. Content filtering policies must be created in IMSVA.

Also, even though Cloud Pre-Filter does filter for viruses, Trend Micro recommends creating antivirus policies.

DKIM

Configure and use this feature as your network requires.

Transport Layer Security (TLS)

If the MTA sending messages to Cloud Pre-Filter supports TLS, the messages are delivered using TLS.

When messages reach Cloud Pre-Filter from an inbound server using TLS, Cloud Pre-Filter delivers the message to the destination server using TLS. If the destination server does not support TLS, the message is delivered over SMTP.

When messages reach Cloud Pre-Filter from an inbound server that does not use TLS, Cloud Pre-Filter delivers the message to the destination server over SMTP.