Plan B
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"Plan B" is also a name for a brand of emergency contraceptive pills
Plan B is an operating system designed to work in distributed environments where the set of available resources is different at different points in time.
It's main design guidelines are:
- All resources are perceived as a single abstraction, the box (instead of traditional file). Boxes are data containers that are operated using copy instead of the traditional read/write. They have type and constraints which determine how they can be used together.
- The system operates on both local and remote boxes through the same protocol. Any implementor of such protocol can be used as part of a Plan B system.
- Each application has its own name space and can customize it. Customization is done by defining names for boxes, as well as the order in which names should be searched.
- Boxes are used by name and no descriptors are kept. Applications keep no connections to resources, they use the network to send self-contained requests.
- Boxes can be advertised as they become available to be automatically bound to pre-specified names in the name spaces of applications that care about such resources.
The design owes much to Plan 9 and to Off++ (http://planb.lsub.org/who/nemo/off.html). For a description of the system, you may read a draft of Plan B: boxes for network resources (http://planb.lsub.org/ls/export/box.html).