diff --git a/types.hpp b/types.hpp
index e792a3e..4f07522 100644
--- a/types.hpp
+++ b/types.hpp
@@ -7,7 +7,7 @@
 #include <vector>
 #include <map>
 #include <memory>
-
+#include <set>
 #include <systemd/sd-event.h>
 
 namespace phosphor
@@ -61,7 +61,7 @@
 
 using AddrList = std::list<AddrInfo>;
 using IntfAddrMap = std::map<IntfName, AddrList>;
-
+using InterfaceList = std::set<IntfName>;
 
 }//namespace network
 }//namespace phosphor