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+NFD - Named Data Networking Forwarding Daemon
+=============================================
+
+Files in this directory are imported from NFD (Named Data Networking Forwarding Daemon)
+project (http://named-data.net/doc/NFD/).
+
+The codebase can be merged with the upstream with the following command:
+
+    git subtree pull --prefix=NFD https://github.com/named-data/NFD master
+
+There are several ndnSIM-specific changes to NFD codebase and manual conflict resolution
+may be required.