#14 R0007/UTF-8 encoding

[David]

R0007: A TEXT SOAP ENVELOPE SHALL be serialized using UTF-8 character encoding.

My assumption is that R0007 is supposed to limit the character encoding to UTF-8 for any XML document transmitted by DPWS.

Unluckily, it suffers from two issues.

First, TEXT SOAP ENVELOPE refers to an application/xml+soap content encoding, which is not applied to UDP messages. Hence, SOAP envelopes conveyed over UDP are allowed to be encoded differently, e.g. UTF-16, so that R0007 does not generate a real benefit as every DPWS implementation must at least support UTF-8 and UTF-16 anyway.

Second, TEXT SOAP ENVELOPE is defined as application/xml+soap which is a binary-encoded format already. And there is no encoding rule from UTF-8 to UTF-8. "A TEXT SOAP ENVELOPE SHALL support UTF-8 only" should be something that works with the mime-type application/xml+soap. Alternatively, I'd tend to rephrase the requirement such that it expresses any SOAP envelope being encoded using UTF-8:

SOAP ENVELOPEs SHALL be encoded by using UTF-8.