diff --git a/network/lookup_asn.sh b/network/lookup_asn.sh
new file mode 100755
index 0000000..b550f91
--- /dev/null
+++ b/network/lookup_asn.sh
@@ -0,0 +1,4 @@
+#!/bin/sh
+
+[ "$#" -ne "1" ] && echo "usage: $0 IP" && exit 1
+whois -h whois.cymru.com " -v $1"