face: ProtocolFactory registry

refs #3904

Change-Id: Ic7c8b3d6138b7c27d4189a2e15cc646055ad1294
diff --git a/daemon/face/udp-factory.cpp b/daemon/face/udp-factory.cpp
index c9b4ac4..d4ee086 100644
--- a/daemon/face/udp-factory.cpp
+++ b/daemon/face/udp-factory.cpp
@@ -42,6 +42,15 @@
 namespace ip = boost::asio::ip;
 
 NFD_LOG_INIT("UdpFactory");
+NFD_REGISTER_PROTOCOL_FACTORY(UdpFactory);
+
+const std::string&
+UdpFactory::getId()
+{
+  static std::string id("udp");
+  return id;
+}
+
 
 void
 UdpFactory::processConfig(OptionalConfigSection configSection,