Client scanning can be performed in two methods:

• Conventional Scan

  A scan method used in all earlier WFBS versions. A Conventional Scan client stores all Security Agent components on the client computer and scans all files locally.

• Smart Scan

  Smart Scan leverages threat signatures that are stored in the cloud. When in Smart Scan mode, the WFBS agent first scans for security risks locally. If the client cannot determine the risk of the file during the scan, the client connects to the local Smart Scan Server. If the clients cannot connect to it, they will attempt to connect to the Trend Micro Global Smart Scan Server.

  Smart Scan provides the following features and benefits:

  • Provides fast, real-time security status lookup capabilities in the cloud.
  • Reduces the overall time it takes to deliver protection against emerging threats.
  • Reduces network bandwidth consumed during pattern updates. The bulk of pattern definition updates only needs to be delivered to the cloud and not to many endpoints.
  • Reduces the cost and overhead associated with corporate-wide pattern deployments.
  • Lowers kernel memory consumption on endpoints. Consumption increases minimally over time.

Trend Micro strongly recommends switching from Conventional Scanning to Smart Scanning:

• Recent statistics shows that the Smart Scan Agent pattern (OTH, which is stored locally on the actual agent that uses Smart Scanning) covers 80% of the total threats, and that the Smart Scan pattern (TBL, stored on the Scan Server) covers the other 20%.
• Aside from Smart Scan Agent pattern (icrc$oth.xxx), a local cache is used to reduce about 80% of outgoing queries. CRC cache works as a partial Smart Scan Pattern replica so that previously obtained CRC can be reused later.

In other words, the CRCs are ready to be used to protect an endpoint user and are effective on malware that have been previously detected. However, the date may vary among individual users according to their usage behavior.