diff --git a/src/intro-cert-list.proto b/src/intro-cert-list.proto
new file mode 100644
index 0000000..6b65a83
--- /dev/null
+++ b/src/intro-cert-list.proto
@@ -0,0 +1,6 @@
+package Chronos;
+
+message IntroCertListMsg
+{
+  repeated string certname = 1;
+}
\ No newline at end of file