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+Acknowledgment
+--------------
+
+This NDN packet format specification is adapted from the CCNx specification described in `<http://www.ccnx.org/releases/latest/doc/technical/index.html>`_ as of October 2013.
+However we have made a number of packet format changes based on our deepened understanding about NDN design through experimentation with NDN over the last three years, and based on the inputs from NDN research community at large. In particular, this specification adopted a TLV encoding format that has been championed by cisco NDN project team.  We list the major protocol format changes from the CCNx specification at the end of each section.