alert tcp $EXTERNAL_NET any -> $HOME_NET 1720 (msg:"ET VOIP Q.931 Call Setup - Inbound"; flow:to_server,established; content:"|08|"; offset:4; depth:1; content:"|05 04|"; distance:3; within:2; classtype:misc-activity; sid:2022023; rev:1; metadata:created_at 2015_11_03, confidence Medium, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2019_07_26;)