docs: Updating copyright notices in files
diff --git a/utils/dummy-keychain.hpp b/utils/dummy-keychain.hpp
index 2af451d..bef13e5 100644
--- a/utils/dummy-keychain.hpp
+++ b/utils/dummy-keychain.hpp
@@ -1,22 +1,21 @@
-/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil -*- */
-/*
- * Copyright (c) 2011-2014 University of California, Los Angeles
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2011-2015  Regents of the University of California.
  *
- * See AUTHORS.md for complete list of authors and contributors.
+ * This file is part of ndnSIM. See AUTHORS for complete list of ndnSIM authors and
+ * contributors.
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation;
+ * ndnSIM is free software: you can redistribute it and/or modify it under the terms
+ * of the GNU General Public License as published by the Free Software Foundation,
+ * either version 3 of the License, or (at your option) any later version.
  *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
+ * ndnSIM is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+ * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
  *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
- */
+ * You should have received a copy of the GNU General Public License along with
+ * ndnSIM, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ **/
 
 #ifndef NDNSIM_UTILS_DUMMY_KEYCHAIN_HPP
 #define NDNSIM_UTILS_DUMMY_KEYCHAIN_HPP