Best Practice Settings This document provides recommends the basic settings to ensure optimal operation for your Email and Web Security Services. For full information on configuring your services, see the Service Administrator Guides at ClientNet > Support > Service & Config Guides. Contents 1 Email Anti-Spam... 2 1.1 Anti-Spam Default Settings... 2 1.2 Anti-Spam Best Practice... 3 2 Email Content Control... 4 3 Email Image Control... 5 4 Web Security Services... 5 BestPracticeSettings_Defaults_v1.3 B Page 1 of 6
1 Email Anti-Spam 1.1 Anti-Spam Default Settings When you are provisioned with the Email Anti-Spam service, the service is enabled with default settings. MessageLabs recommends that you evaluate the tagged spam that you receive using these settings and how they work for your oragnization s mail flow. When you are confident that the service is only detecting spam email, you may wish to configure the best practice settings (see Section 1.2). To locate the Anti-Spam detection settings: Navigate to Configuration > Email Services Configuration > Anti-Spam. The Detection Settings page is displayed with the following settings: BestPracticeSettings_Defaults_v1.3 B Page 2 of 6
Important: The settings for the RBL and RSS public block lists and for Skeptic heuristics are set with an action to tag the subject line and allow the email through. Therefore, you will still receive spam detected by these methods. 1.2 Anti-Spam Best Practice When you are confident that the default detection methods are only detecting spam, MessageLabs recommends that you set the action for the RBL and RSS public block lists and for Skeptic heuristics to block and delete to ensure full Anti-Spam protection. Note: For full details of these settings, see the Email Anti-Spam Administrator Guide. BestPracticeSettings_Defaults_v1.3 B Page 3 of 6
2 Email Content Control When you are provisioned with the Email Content Control service, the service has no rules set up. The rules you define for Content Control assist in monitoring and controlling your company s acceptable use policy. MessageLabs recommends that initially you set up five rules to just log various aspects of content within emails, as follows: Log inbound emails over 2Mb Log outbound profanities Log all encrypted email inbound and outbound Log inbound emails over 10Mb Log audio and video files inbound and outbound Then once you are familiar with kinds of emails that are being detected, you can feel more confident in blocking some, and redirecting others. The following are some common rules, but note that every organization is different. We recommend that you do not simply set up these example rules without understanding your business needs and aligning an email security policy with them: Block emails over 25MB reduces the amount of email coming into the organization to save bandwidth. All emails over 25MB can be blocked and deleted, and notifications sent to all parties. Monitor outbound profanities protects the organization s brand and reputation. You may wish to block employees from sending out emails containing profanities, even to friends. Redirect encrypted or password-protected mail enables administrators to monitor and control who is sending and receiving encrypted or password-protected messages. Compress emails between 10MB and 25MB reduces the bandwidth taken up by large messages coming into the organization. Redirect emails to/from suspicious domains monitors emails coming from or going out to competitors domains, restricting the passing on of intellectual property and poaching of employees. Block audio and video file attachments or you may wish to restrict audio and video files to be received only by the Marketing department. To locate the Content Control configuration pages: Select Configuration > Email Services Configuration > Content Control. Note: Rules are performed in the order that they are listed. BestPracticeSettings_Defaults_v1.3 B Page 4 of 6
3 Email Image Control MessageLabs recommends that initially the following settings are used for both inbound and outbound mail: The action to Copy suspected mail to is used for all detection methods you can arrive at the most appropriate actions for your organization by adjusting the settings and observing the results. Select low or medium sensitivity for the Heuristics detection method you can arrive at its optimum sensitivity setting by adjusting the settings and observing the results. To locate the Image Control configuration pages: Select Configuration > Email Services Configuration > Image Control 4 Web Security Services When you are provisioned with the Web Security Service, it is enabled with default settings. A policy rule is defined to block traffic to web pages with URLs that are known to contain content in the following categories: Adult/Sexually Explicit, Criminal Activity, Spam URLs, and Spyware. This rule constitutes the best practice setting for the Web Security Service. You can, of course, configure further rules to reflect your organization s Acceptable Use Policy, but MessageLabs recommends that you keep the default rule as a minimum default setting. To locate the Web Security Service settings: 1. Navigate to Configuration > Web Security Services Configuration > Web URL Filtering. The Policy Rules page is displayed with a rule called Default Settings is displayed. BestPracticeSettings_Defaults_v1.3 B Page 5 of 6
To view the components of the rule, click on the name of the rule. The Rule tab is displayed showing the rule name and Block & Log action setting. 2. Click on the URL Categories tab. The Use URL Categories below checkbox is selected and the following four categories are checked Adult/Sexually Explicit, Criminal Activity, Spam URLs, and Spyware: Note: For full details of Web Security Services settings, see the Web Security Services V2 Administrator Guide. BestPracticeSettings_Defaults_v1.3 B Page 6 of 6