A standard way of doing binary WS is FastInfoset

http://java.sun.com/developer/technicalArticles/xml/fastinfoset/

The Fast Infoset standard draft (currently being developed as joint work by ISO/IEC JTC 1 and ITU-T) specifies a binary format for XML infosets that is an efficient alternative to XML. An instance of this binary format is called a fast infoset document. Fast infoset documents are analogous to XML documents. Each has a physical form and an XML infoset. Fast infoset documents are, given the results presented, faster to serialize and parse, and smaller in size, than the equivalent XML documents. Thus, fast infoset documents may be used whenever the size and processing time of XML documents is an issue.