MD5 Hash is a widely used hash function used as a checksum to verify message data intergrity. By specifying an MD5 hash that is unique to the file you upload in the Content Examination definition, you can prevent confidential documents from leaving your environment. If we detect the hash in a message, the action specified in the definition is taken.
Adding a File MD5 Hash to a Definition
To add a File MD5 Hash to a definition:
- Log on to the Administration Console.
- Click on the Administration menu item. A menu drop down is displayed.
- Click on the Gateway | Policies menu item.
- Hover over the Definitions button. A list of the definition types is displayed.
- Click on the Content Examinations definition type from the list. The list of definitions is displayed.
- Either click on the:
- Definition to be changed.
- New Content Definition button.
- Click on the Insert button.
- Click on the File MD5 Hash menu item.
- Complete the Policy Definition dialog as follows:
Field / Option Description Line Score Specify a value for the MD5 hash, that is compared to the "Activation Score" in the definition. Append If selected, the MD5 hash is placed at the bottom of the "Word / Phrase Match List". If unselected, it is placed at the top of the list. Attachment MD5 Hash Specify an automatically generated MD5 hash that is unique to the file specified in the "New File Upload" field.This is used to prevent confidential documents from leaving your environment. By uploading the document, a MD5 hash is generated. If we detect the hash in a message, the action specified in the definition is taken. New File Upload Click on the Browse button to select the required file. Comment Add any notes that refer to the MD5 hash. These are only displayed in the "Word / Phrase Match List" field prefixed by a hash symbol (#). All comments are ignored when examining messages for matches.
- Click on the Save and Exit button.
- Repeat steps 7 - 10 to add any additional File MD5 Hash to the definition.