file-frame stream-detect enable

By default, stream decoding detection for mail protocol transferred files is disabled.

Mail protocol transferred files are usually processed by the mail proxy function. Antivirus detection and file restoration are performed for cached files. If the FW does not have the content security component package loaded or the corresponding license activated, the mail proxy function is unavailable, antivirus detection and file restoration are not performed on mail protocol transferred files. In this scenario, stream decoding detection for mail protocol transferred files shall be enabled so that antivirus detection and file restoration can be performed on files without the mail proxy function. For details about the component package, see Dynamic Loading.

Antivirus detection and file restoration are performed only after the mail proxy function caches files. Therefore, the FW can promptly block mail transfer or delete files with threats. In stream decoding detection mode, the FW can only detect viruses and report logs but not block mails in real time or delete files with threats.