On the IBM i, transport of binary data is not supported. This mean you can't talk to services that require you to send a file, or return a file (unless you know that the file's content is text only).
If you need to invoke file-related web services on the IBM i platform, you will need to use an intermediary server (software) that can encode/decode the binary data. The intermediary server software must run on the same machine that consumes the web services. The best choice would be to use the Java servlet technology, hosted inside one of the freely available servlet containers such as Tomcat.
Note that this limitation applies only to the IBM i platform. On Windows, no such limitation exists, and you are free to send & receive binary data in your requests.
