Server_Component_Duplication

Server Component Duplication

When the latest version of a full pattern file is available for download from the Trend Micro ActiveUpdate server, 14 "incremental patterns" also become available. Incremental patterns are smaller versions of the full pattern file that account for the difference between the latest and previous full pattern file versions. For example, if the latest version is 175, incremental pattern v_173.175 contains signatures in version 175 not found in version 173 (version 173 is the previous full pattern version since pattern numbers are released in increments of 2. Incremental pattern v_171.175 contains signatures in version 175 not found in version 171.

To reduce network traffic generated when downloading the latest pattern, OfficeScan performs component duplication, a component update method where the OfficeScan server or Update Agent downloads only incremental patterns. See Update Agent Component Duplication for information on how Update Agents perform component duplication.

Component duplication applies to the following components:

Component Duplication Scenario

To explain component duplication for the server, refer to the following scenario:

Server component duplication scenario

Full patterns on the OfficeScan server

Current version: 171

Other versions available:

169     167     165     163     161     159

Latest version on the ActiveUpdate server

173.175     171.175     169.175     167.175     165.175

163.175     161.175     159.175     157.175     155.175

153.175     151.175     149.175     147.175

  1. The OfficeScan server compares its current full pattern version with the latest version on the ActiveUpdate server. If the difference between the two versions is 14 or less, the server only downloads the incremental pattern that accounts for the difference between the two versions.

  2. To illustrate based on the example:

  3. The server merges the incremental pattern with its current full pattern to generate the latest full pattern.

  4. To illustrate based on the example:

  5. The server generates incremental patterns based on the other full patterns available on the server. If the server does not generate these incremental patterns, clients that missed downloading earlier incremental patterns automatically download the full pattern file, which will consequently generate more network traffic.

  6. To illustrate based on the example:

    169.175     167.175     165.175     163.175     161.175     159.175

    171.175     169.175     167.175     165.175     163.175     161.175     159.175

  7. The server compares its current incremental patterns with the incremental patterns available on the ActiveUpdate server. The server downloads the incremental patterns it does not have.

  8. To illustrate based on the example:

    173.175     171.175     169.175     167.175     165.175     163.175     161.175

    159.175     157.175     155.175     153.175     151.175     149.175     147.175

    171.175     169.175     167.175     165.175     163.175      161.175     159.175

    173.175     157.175     155.175     153.175     151.175     149.175     147.175

  9. The latest full pattern and the 14 incremental patterns are made available to clients.

See also: