Accessing Files in an Internet: The Jade File System

This paper introduces the Jade File System, which provides a uniform way to name and access files in an internet environment. Jade is a logical system that integrates a heterogeneous collection of existing file systems, where by heterogeneous we mean that the underlying file systems support different file access protocols. Because of autonomy, Jade is designed under the restriction that the underlying file systems may not be modified. In order to avoid the complexity of maintaining an internet-wide, global name space, Jade permits each user to define a private name space. Jade’s name space supports two novel features: It allows multiple file systems to be mounted under one directory, and it permits one logical name space to mount other logical name spaces. A prototype of Jade has been implemented to examine and validate its design. The prototype consists of interfaces to the Unix File System, the Sun Network File System, and the File Transfer Protocol. This paper gives an overview of Jade’s design, and reports our experiences designing and implementating a large scale file system.