Understanding Cloud Pre-Filter Policies Parent topic

The Cloud Pre-Filter service offers policy-based management of your email security. The policy for a domain regulates how each filter is applied to messages sent to the domain.
The following table lists the information that defines each policy.

Cloud Pre-Filter Policies

Section
Description
Domain
The domain that will be covered by the policy. With the correct routing settings, all messages to this domain are protected by Cloud Pre-Filter.
Each domain must be unique, and only one policy can be applied to a domain.
Valid Recipient
This setting works by comparing the list of users on your LDAP servers to a list of your users on Cloud Pre-Filter. The Cloud Pre-Filter list of your users is generated by synchronizing with your LDAP servers.
Use the valid recipient check to block all messages that do not have a recipient on your domain. This prevents malicious messages and spam from reaching your network.
Filter settings
These settings define the following Cloud Pre-Filter filtering options:
  • Whether a filter is enabled or not
  • For filters that support this option, how each filtering criterion is applied
  • For filters that support this option, what filter actions to perform
Destination servers
Destination servers are the inbound mail servers for the domain. These servers receive messages bound for the domain after they are processed by the Cloud Pre-Filter service.
Approved and blocked senders
  • Approved Sender: Messages from approved senders bypass the Email Reputation service and antispam filters.
  • Blocked Sender: Messages from blocked senders are blocked immediately and never reach your network.
Note
Note
Trend Micro recommends that you create Cloud Pre-Filter policies that mirror, but are less aggressive than, on-premise IMSVA policies. Using duplicate policies helps protect your business in the unlikely event that Cloud Pre-Filter becomes unavailable.

Considerations Parent topic

  • Each policy applies to one domain only and only one policy can be created for each domain.
  • A policy comprises of a domain, filtering settings, approved and blocked sender lists, and destination servers.
  • Review each filter type and assess whether you want to apply it to a domain before saving the policy. The following filters are enabled by default:
    • Email Reputation
    • Antivirus
    • Antispam
Tip
Tip
Trend Micro recommends that you have the antivirus and antispam filters enabled and properly configured. Without these filters, the domain is highly vulnerable to large numbers of unwanted mail and infected messages.