The Proofpoint Messaging Security Gateway P840 (v5.0) had excellent overall anti-spam performance, third in filtering and fifth in false positives, with a fair number of bulk false positives, but more than 97 per cent of spam caught. And the feature set is extensive, including application-layer firewall features for the back-end mail server, policy-based encryption, and capable outbound content protection.
The Proofpoint solution is very much an enterprise-oriented, security-focused appliance, to the extent that it enforces complex passwords for the administrator login. Passwords must be at least seven characters and must contain punctuation as well as numbers, thus guaranteeing that passwords will be written down and stuck to a monitor somewhere. In spite of the appliance having a default IP address, the initial configuration can only be done by KVM, using a USB keyboard, which many KVMs don't support, meaning that the initial configuration will require carrying a separate USB keyboard and monitor to the system for the first minute of setup.
The burdensome initial configuration out of the way, the rest of the configuration, LDAP included, is easy and straightforward. The administration interface is first rate, and there are many options for securing corporate data. Filtering for compliance or protection of intellectual property is simple to set up and flexible to administer.
The enterprise class features include a good Outlook plug-in, excellent reporting and logging tools, and user, group, and domain-based policies. Proofpoint includes lists of words for secure content management and policy enforcement, and appliances can be clustered for additional capacity and fault tolerance.
Although the pricing for the Proofpoint Messaging Security Gateway is the highest of the products tested (for 1,000 users), it offers a broad set of features and a high spam catch rate.