alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"GPL POLICY Windows Media Video download"; flow:from_server,established; content:"Content-type|3A| video/x-ms-asf"; nocase; classtype:policy-violation; sid:2101438; rev:14; metadata:created_at 2010_09_23, confidence Medium, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2019_07_26;)