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Re: XML is text-only ... why?

• From: "Stephen D. Williams" <sdw@l...>
• To: Alessandro Triglia <sandro@m...>
• Date: Wed, 03 Oct 2007 08:39:13 -0400

Fast Infoset is not what W3C Efficient XML Interchange (EXI) is based 
on, although it is one of the candidates considered in detail, along 
with my Efficiency Structured XML 1.0 (ESXML).

Here is our first public working draft of the EXI format:
http://www.w3.org/TR/2007/WD-exi-20070716/

I feel it is an incomplete baseline in a number of ways, however it 
includes most of the base structure and encoding method and is a 
significant milestone.

I initiated the OpenEXI open source implementation and Santiago 
Pericas-Geertsen and others quickly joined.  OpenEXI is hosted as an 
open source project by Sun, although I don't believe the project 
codebase is public quite yet.

sdw

Alessandro Triglia wrote:
>> -----Original Message-----
>> From: Jonathan Robie [mailto:jonathan.robie@r...] 
>> Sent: Wednesday, September 26, 2007 10:56
>> To: Costello, Roger L.
>> Cc: xml-dev@l...
>> Subject: Re:  XML is text-only ... why?
>>
>> Here's a few thought experiments.
>> ...
>>
>> Answer: To me, this is a useful way of thinking about binary XML. 
>> Encoding a document in various ways and extending it with 
>> annotations for processing have a long tradition in SGML and XML.
>>
>> Note: Suppose you think of binary documents as an alternate 
>> encoding that you need software to read, with great 
>> performance characteristics. 
>> What is lost? Primarily the archival value of being able to 
>> read any language in an encoding and language you understand. 
>> But if there were a standard binary encoding that had all the 
>> above performance characteristics
>>     
>
>
> There is a standard already.
>
> Fast Infoset is compact enough and fast enough for many practical purposes.
> It is an ISO/IEC standard and an ITU-T Recommendation.  It is designed and
> specified around the XML infoset and therefore it fits very well the data
> model of such standards as XPath, XQuery, and XML Schema.  For example, XML
> Schema's validity assessment is specified in terms of an XML infoset being
> validated, as opposed to an XML document being validated.
>
> Fast Infoset addresses "typing" in a special way.  It does not try to encode
> any "values" of any "types".  Instead, it provides a standard set of
> encoding algorithms which a document creator can use to generate an
> optimized representation of certain **character strings**.  The "data" being
> encoded is still **characters**--it just happens that those characters are
> represented as an integer or as a string of bytes in the fast infoset
> document.  There is no dependency on a schema, even though the document
> creator is free to exploit any a-priori knowledge of the documents
> (including schemas) to decide what optimizations to use.  Then any consumer
> will be able to read the document without having the same a-priori knowledge
> the creator had.
>
> There are several implementations available on different platforms and
> languages, including the Sun-coordinated open source project.
>
> Alessandro Triglia
>
>
>   
...

-- 
swilliams@h... http://www.hpti.com Per: sdw@l... http://sdw.st
Stephen D. Williams 703-371-9362C 703-995-0407Fax 20147 AIM: sdw