alert udp $HOME_NET any -> $EXTERNAL_NET any (msg:"ET P2P BitTorrent DHT ping request"; content:"d1|3a|ad2|3a|id20|3a|"; depth:12; nocase; threshold:type both, count 1, seconds 300, track by_src; reference:url,wiki.theory.org/BitTorrentDraftDHTProtocol; classtype:policy-violation; sid:2008581; rev:3; metadata:created_at 2010_07_30, confidence High, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2019_07_26;)