Presents resource Grid Transparent access to distributed, cross-platform resources

resource Grid Transparent access to distributed, cross-platform resources Make multiple resources available to many users over existing networks using inferno Grid technology Resource interfaces represented by a hierarchical namespace Import data, devices and programs Intuitive, per process composition of namespaces Secure, platform independent communication protocol

resource Grid What is a namespace? A namespace is a hierarchical collection of names These names may represent actual physical files sales.db customers.db ctl images img0001.jpg img0002.jpg database camera or a resource interface ctl images img0001.jpg img0002.jpg sales.db customers.db customers.dbsales.dbctlimages/ Each resource is accessed with the same mechanisms, irrespective of type and location ls /database ls /camera/images ls does not need to know what kind of resource it is talking to The file system returns a list of files in the /database directory The camera interface returns a list of images on the camera

resource Grid Exporting and Importing Namespaces Complete or partial namespaces may be exported and used over a network

resource Grid Each device on the network has its own local namespaceA device may export all or part of its local namespace ctl images books camera Exporting and Importing Namespaces history medieval modern history ancient mythical Another device may then import this namespace into its own local namespace Namespaces may be built up from multiple imported local or remote namespaces history ancient medieval modern ancient Once a namespace has been composed, the user may access each resource without needing to know where it comes from Local Remote (imported) cp /camera/images/0001.jpg /books/history/ancient As far as cp knows, it is just copying a local file 0001.jpg copy

resource Grid Why Files? Representing all resource interfaces as files has several advantages: File systems have simple and well understood interfaces across a wide variety of operating systems Interfaces to files generally consist of a small set of well-defined operations such as open, read and write Reliance on file systems reduces the amount of interface code and keeps the system small, reliable and highly portable Naming conventions for files are well known, uniform and easily understood Access rights and permissions to files are simple, yet can be used to ensure multiple levels of security

resource Grid Device Interface Example ctlControl messages are written to this file statusCan be read to provide status information images/Directory containing the images on the camera A device interface exports a namespace which is used to interact with the device. These synthetic files may be accessed using standard file operations and commands. echo snap > ctl echo zoom 250 > ctl cat status ls -l images cp images/* /pics rm images/0001.jpg Take a photo Set zoom to 2.5 x magnification Read the status Get a list of images on the camera Copy all camera images to /pics Delete image 0001.jpg from the camera images/statusctl

resource Grid Read Image open images/open ctlopen images/p jpg images/status close statusclose images/close images/p jpg write ‘snap’ open status Read images/Read StatusTake PhotoChange Zoom close ctl Device Interface Example A graphical user interface for the device simply needs to interact with the same files File Operations write ‘zoom 300’ read images/ctl status

resource Grid “[We wanted] the ability to access file resources distributed across multiple machines, securely and intuitively. Until we discovered the Inferno Data Grid this was not a simple task. We are very pleased with the outcome.” Brian Hancock Digital Projects Librarian at Rutgers University