alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET POLICY External IP Check myexternalip.com"; flow:established,to_server; http.method; content:"GET"; http.host; content:"myexternalip.com"; depth:16; endswith; classtype:external-ip-check; sid:2019980; rev:6; metadata:created_at 2014_12_20, confidence High, signature_severity Informational, updated_at 2020_09_17;)