34. A computer-accessible storage medium comprising program instructions, wherein the program instructions are configured to implement: a Web services stack communicating with another Web services stack according to a markup language protocol, wherein the markup language protocol is based on XML (eXtensible Markup Language); and the Web services stack dynamically switching to communicating with the other Web services stack according to a binary encoding protocol wherein communication according to the binary encoding protocol comprises mapping from an XML schema to a binary encoding schema and generating a binary encoding from the binary encoding schema; wherein the Web services stack supports the markup language protocol and the binary encoding protocol with a single API (application programming interface).
34. A computer-accessible storage medium comprising program instructions, wherein the program instructions are configured to implement: a Web services stack communicating with another Web services stack according to a markup language protocol, wherein the markup language protocol is based on XML (eXtensible Markup Language); and the Web services stack dynamically switching to communicating with the other Web services stack according to a binary encoding protocol wherein communication according to the binary encoding protocol comprises mapping from an XML schema to a binary encoding schema and generating a binary encoding from the binary encoding schema; wherein the Web services stack supports the markup language protocol and the binary encoding protocol with a single API (application programming interface). 43. The computer-accessible storage medium as recited in claim 34 , wherein, in said communicating with the other Web services stack according to the binary encoding protocol, the program instructions are further configured to implement serializing the markup language protocol to generate binary encoding protocol messages according to a schema-optimized binary format for transmitting data described by markup language schema.