XML Catalogs information

["Lauren Wood" <lauren@textuality.com>]

Mary, 

if you find it appropriate, the Entity Resolution TC would like you 
to include the attached information about catalogs to the 
notification of the vote that you are sending out to the OASIS member 
companies.

regards,

Lauren Wood, ER TC Chair

--------------------

XML documents and data often reference other external resources.  
Often the referencing information is not sufficient to locate the 
desired resource unambiguously, or the resource is not accessible at 
the given location at the time it is required, or it is preferable 
that an alternate resource be used in place of the referenced 
resource.  

For example:

1. External identifiers may require resources that are not always 
available. For example, a system identifier that points to a resource 
on another machine may be inaccessible if a network connection is not 
available.  

2. External identifiers may require protocols that are not accessible 
to all of the tools on a single computer system. An external 
identifier that is addressed with the FTP protocol, for example, is 
not accessible to a tool that does not support that protocol.  

3. It is often convenient to access resources using system 
identifiers that point to local resources. Exchanging documents that 
refer to local resources with other systems is problematic at best 
and impossible at worst.  

4. Incoming XML documents may reference customized versions of 
standard XML schemas.  To protect your systems, it is necessary to 
remap the schema references so that known, trusted copies of the 
schemas are used.  

Entity Resolution is the process by which these resource references 
can be mapped to another version of the reference that can be found 
or that is preferred for other reasons.  To address these issues, the 
OASIS XML Catalog specification defines an application-independent 
entity catalog that maps external identifiers and URI references to 
(other) URI references.  

Entity resolution catalogs have already been widely implemented in 
much deployed software.  Promoting the OASIS XML Catalog 
specification to an OASIS Standard is crucial for continued  
interoperability of XML applications.