(registered 2014-01-29, last updated 2014-01-29)

MIME media type name : Application

MIME subtype name : Standards Tree - bacnet-xdd+zip

Required parameters : none

Optional parameters : none - content provides its own versioning and manifest

Encoding considerations : binary

Security considerations : 
This is a zip file. The standard contents are a textual manifest and XML and/or 
JSON files. There is no standard executable or interpretable content. However, 
there is a vendor extensible area where arbitrary content can be provided. 
Consumers of these extended files are advised to use the same safety precautions 
as if these files had been loaded separately. 

The standard use case of the file is to represent inherently public information 
and there is no standard support in the file to protect the contents from 
inspection during transmission or storage. The information defines data types 
and data arrangement. Tampering with this could possibly cause operator 
confusion about what data is being viewed or modified. Even though the security 
of the data "on the wire" is provided by the underlying communication protocol, 
operator confusion could cause incorrect data to be modified if a single 
authorization scope includes both a real and a maliciously substituted target. 
Therefore, consumers of this definition information are advised to ensure the 
file came from a trusted source. The level of this assurance should be 
appropriate for the risk level of the data being described.

General security considerations for XML and JSON are given in Section 10 of 
RFC 3023 and Section 6 of RFC 4627, respectively.

Interoperability considerations : 

Published specification : 
Host standards are/will be: ANSI/ASHRAE Standard 135-2012 and ISO 16484-5
This media type will be defined in second public review of Addendum ba to 135-2012. 
First public review document originally published at http://osr/ashrae/org and 
archived at http://www.bacnet.org/Addenda/Add-135-2012ba-ppr1-draft-2_chair_approved.pdf

Applications which use this media : 
Provided by BACent devices; consumed by BACnet clients and workstations.

Fragment identifier considerations : None

Additional information :

1. Magic number(s) : It's a zip file; thus commonly: PK\003\004
2. File extension(s) : xdd
3. Macintosh file type code : none
4. Object Identifiers: none

Person to contact for further information :

1. Name : Dave Robin
2. Email : iana2&daverobin.com

Intended usage : Common
BACnet is the leading international standard for Building Automation Systems. 
It is expected that this will be widely deployed to allow BACnet devices and 
installations of BACnet devices to be richly "discoverable", providing both 
human-readable descriptions and machine-readable structural and semantic 
information.

Author/Change controller : American Society of Heating, Refrigerating and 
Air-Conditioning Engineers (ASHRAE), ashrae&ashrae.org, 1791 Tullie Circle, 
N.E. Atlanta, GA 30329