diff --git a/controller.py b/controller.py
index 7043466..17e2afb 100644
--- a/controller.py
+++ b/controller.py
@@ -37,7 +37,7 @@
     print(result)
 
 class Controller(BaseNode):
-    def __init__(self,configFileName):
+    def __init__(self,configFileName=None):
         super(Controller, self).__init__(configFileName=configFileName)
         self._responseCount = 0
         self._symmetricKey = "symmetricKeyForBootstrapping"
@@ -166,7 +166,7 @@
             self._keyChain.createIdentityAndCertificate(identityName)
        	    self._identityManager.setDefaultIdentity(identityName)
 
-	self.face.setCommandSigningInfo(self._keyChain, self.getDefaultCertificateName())
+	self.face.setCommandSigningInfo(self._keyChain, self._keyChain.getDefaultCertificateName())
         self.face.registerPrefix(self._prefix, self.onInterest, self.onRegisterFailed)