proposed namespace URI versioning policy

All,

I have taken a stab at a proposed namespace versioning policy, that would 
be stated both in the
specification and in the namespace document (RDDL). This is derived from 
other standards work,
most specifically the OASIS WS-RX TC's policy for it namespace.

Proposed Namespace URI Versioning Policy:

It is the intent of the W3C WS-Policy Working Group that the WS-Policy 
Framework v1.5 and WS-Policy Attachment v1.5 namespace URI will not change 
arbitrarily with each subsequent revision of the corresponding XML Schema 
documents but rather change only when a subsequent revision, published as 
a WD, CR or PR draft results in non-backwardly compatible changes from a 
previously published WD, CR or PR draft of the specification.
Under this policy, the following are examples of backwards compatible 
changes that would not result in assignment of a new namespace URI: 
addition of new global element, attribute, complexType and simpleType 
definitions
addition of new elements or attributes in locations covered by a 
previously specified wildcard
modifications to the pattern facet of a type definition for which the 
value-space of the previous definition remains valid or for which the 
value-space of the preponderance of instance would remain valid
modifications to the cardinality of elements for which the value-space of 
possible instance documents conformant to the previous revision of the 
schema would still be valid with regards to the revised cardinality rule

Cheers,

Christopher Ferris
STSM, Software Group Standards Strategy
email: chrisfer@us.ibm.com
blog: http://www.ibm.com/developerworks/blogs/dw_blog.jspa?blog=440
phone: +1 508 377 9295