Chapter 4 FortiOS Carrier : MMS Security features : MMS virus scanning : Passing or blocking fragmented messages
  
Passing or blocking fragmented messages
Select to pass fragmented MM3 and MM4 messages. Fragmented MMS messages cannot be scanned for viruses. If you do not select these options, fragmented MM3 and MM4 message are blocked.
The Interval is the time in seconds before client comforting starts after the download has begun, and the time between sending subsequent data.
The Amount is the number of bytes sent by client or server comforting at each interval.