.. _packetFormat:

Query

Requests to the zone are made in the format of a standard NDN interest.

See :ref Interest section <http://named-data.net/doc/ndn-tlv/interest.html>_ for details.

Answer

.. _data:

Data ::= DATA-TLV TLV-LENGTH
    Name
    MetaInfo
    Content
    Signature

Every response from the NDNS system comes in the same generic form. Specialization of different types of NDNS responses is accomplished through NDNS Type field of MetaInfo.

See :ref NDNS Type section for details

Name

See :ref:`Name section <Name>` for details.


.. _MetaInfo

MetaInfo

MetaInfo specified here represents portions that are defaultly specified in any NDN packet with NDNS specific additions.

See NDN Packet Specification - Meta-Info <http://named-data.net/doc/ndn-tlv/data.html#metainfo>_

MetaInfo ::= META-INFO-TYPE TLV-LENGTH ContentType FreshnessPeriod? NDNS-Type AnswerCount

ContentType +++++++++++

::

    ContentType ::= CONTENT-TYPE-TYPE TLV-LENGTH 
                  nonNegativeInteger

For an NDNS packet the ContentType should always be BLOB (=0), specificity is accomplished by NDNS-Type.

See :ref: NDNS-Type for details

FreshnessPeriod +++++++++++++++

::

    FreshnessPeriod ::= FRESHNESS-PERIOD-TLV TLV-LENGTH 
                      nonNegativeInteger

The optional freshness period specifies how long after the arrive of the data the recieving node should wait before marking it stale.

See NDN Packet Specification - Freshness Period <http://named-data.net/doc/ndn-tlv/data.html#freshnessperiod>_

.. _NDNS-Type:

NDNS-Type +++++++++

::

    NDNS-Type ::= NDNS-TYPE-TLV TLV-LENGTH
                nonNegativeIntegear

There are 3 distinct types of NDNS Responses: +-----------+------------------------------------------------------------------+ | Type | Description | +===========+==================================================================+
| NDNS Data | indicates an answer was found, and that contains the requested | | | content | +-----------+------------------------------------------------------------------+
| NDNS NACK | indicates that the responding zone has no content matching the | | | query. | +-----------+------------------------------------------------------------------+ | NDNS AUTH | indicates that the zone has content, but a more specific | | | question is need to determine the correct content to server. | +-----------+------------------------------------------------------------------+

.. _AnswerCount:

AnswerCount ++++++++++++

::

        AnswerCount ::= ANSWER-COUNT-TLV TLV-LENGTH
                nonNegativeIntegear

This field is used to specify the number of answer in a response.

Content

::

            Content ::= CONTENT-TYPE TLV-LENGTH BYTE*
            
Signature

::

        Signature ::= SignatureInfo
                      SignatureBits

See NDN Signature Specification - Signature <http://named-data.net/doc/ndn-tlv/signature.html>_