diff --git a/.zsh/config.sh.d/portknock.sh b/.zsh/config.sh.d/portknock.sh
new file mode 100644
index 0000000..272adbb
--- /dev/null
+++ b/.zsh/config.sh.d/portknock.sh
@@ -0,0 +1,10 @@
+# pknock provides a port-knock tool based on ncat
+function pknock {
+  HOST="$1"
+
+  # Perform port knocking sequence
+  echo "Knocking requested port sequence (${HOST} - ${*:2})" >&2
+  for i in ${*:2}; do
+    ncat -w 50ms "${HOST}" $i 1>/dev/null 2>&1
+  done
+}