Portability: Java Web Start is available on Windows, Solaris, and Linux, and is expected to be ported to other platforms. Caching: Applications launched with Java Web Start are cached locally.

Sun Microsystems announced Wednesday at Internet World that it is shipping its Java Web Start software, which allows users to launch Java applications without worrying whether the Java platform is ...

Since JNLP files are simply Java Web Start files that open applications through an Internet browser, any browser that works in Windows 8.1 will open a JNLP file as long as you have Java installed.