diff --git a/discovery-utils/proto/discovery.proto b/discovery-utils/proto/discovery.proto
index ee279a394..de8db89db 100644
--- a/discovery-utils/proto/discovery.proto
+++ b/discovery-utils/proto/discovery.proto
@@ -34,7 +34,7 @@ service DiscoveryHandler {
 }
 
 message ByteData {
-    optional bytes vec = 1;
+    bytes vec = 1;
 }
 
 message DiscoverRequest {