Creating/editing a DLP sensor

DLP sensors are collections of filters. You must also specify an action for the filter when you create it in a sensor. Once a DLP sensor is configured, you can select it a security policy profile. Any traffic handled by the security policy will be examined according to the DLP sensor configuration.

 

To create/edit a DLP sensor

1. Go to Security Profiles > Data Leak Prevention.

2. Choose whether you want to edit an exiting sensor or create a new one.

• The default sensor will be the one displayed by default.
• If you are going to edit an existing sensor, selecting it can be done by either using the drop down menu in the upper right hand corner of the window or by selecting the List icon (the furthest right of the 3 icons in the upper right of the window, if resembles a page with some lines on it), and then selecting the profile you want to edit from the list.
• If you need to create a new sensor you can either select the Create New icon (a plus sign within a circle) or select the List icon and then select the Create New link in the upper left of the window that appears.

3. Enter a name in the Name field for any new DLP sensors.

4. Optionally, you may also enter a comment. The comment appears in the DLP sensor list and can remind you of the details of the sensor.

5. At this point you can add filters to the sensor (see adding filters to a DLP sensor) or select OK to save the sensor. Without filters, the DLP sensor will do nothing.

 

Adding filters to a DLP sensor

Once you have created a DLP sensor, you need to add filters.

1. To add filters to a DLP sensor

2. Go to Security Profiles > Data Leak Prevention.

3. Select the Sensor you wish to edit using the drop down menu or the sensor list window.

4. Within the Edit DLP Sensor window select Create New. A New Filter window should pop up.

5. Select the type of filter. You can choose either Messages or Files. Depending on which of these two are chosen different options will be available.

 

Message filter will have these configuration options:

• [radio button] Containing: [drop down menu including: Credit Card # or SSN]
• [radio button] Regular Expression [input field] Examine the following Services:

Web Access

• HTTP-POST

 

Email

• [check box] SMTP
• [check box] POP3
• [check box] IMAP
• [check box] MAPI

 

Others

• [check box] NNTP

 

Action [from drop down menu]

• None
• Log Only,
• Block
• Quarantine IP address

 

Files filter will have these options:

• [radio button] Containing: drop down menu including: Credit Card # or SSN
• [radio button] File Size >= [ ]KB
• [radio button] Specify File Types

File Types: [“Click to add…”drop down menu of File extensions] File Name Patterns:[“Click to add…”drop down menu]

• [radio button] File Finger Print : [drop down menu]
• [radio button] Watermark Sensitivity: [drop down menu] and Corporate Identifier [id field]
• [radio button] Regular Expression [input field]
• [radio button] Encrypted Examine the following Services: Web Access
• [check box] HTTP-POST
• [check box] HTTP-GET

Email

• [check box] SMTP
• [check box] POP3
• [check box] IMAP
• [check box] MAPI

 

Others

• [check box] FTP
• [check box] NNTP

 

Action [from drop down menu]

• None
• Log Only,
• Block
• Quarantine IP address

6. Select OK.

7. Repeat Steps 6 and 7 for each filter.

8. Select Apply to confirm the settings of the sensor.

If you have configured DLP to block IP addresses and if the FortiGate unit receives ses- sions that have passed through a NAT device, all traffic from that NAT device — not just traffic from individual users — could be blocked. You can avoid this problem by implementing authentication.