More information about use cases will be posted here shortly, but some notes in the meantime...

Use case documents that we have produced

Click on this link for the UseCasesPaper - identifying use cases for a generic grid.

See also [http://users.ox.ac.uk/~markn/GridUseCases/ Grid Use Cases] for the documents produced for and after the Focus Group Meeting.

See also [http://users.ox.ac.uk/~markn/OxUseCases/ Oxford Use Cases] for (largely role-based) access control issues, taken from a study of existing and planned projects associated with Oxford University. These use cases are 'information environment' applications (but some involve data processing for users), but the groups of users highlighted could easily be interpreted as strong potential grid users.

Work in progress

See the Use Case paper currently being written at http://users.ox.ac.uk/~markn/Presentations/UsabilityPaperv01.pdf. This is for the [http://www.nesc.ac.uk/esi/events/613/ Designing for e-Science: Interrogating new scientific practice for usability, in the lab and beyond] workshop/meeting at NeSC on 26-27 Jan 06. This paper may be accepted and published in a special issue in the International Journal of Human Computer Studies on EScience Applications and Usability Design, arising from the meeting.

Useful Use Cases references

Stephen Pickles' [wiki:RequirementsBibliography Use Cases for Advance Reservation and Co-allocation] presentation at PSNC Workshop on Resource Management, Poznan, 22 October, 2003, includes 'Steering Grid Service' (SGS) Use case

[wiki:RequirementsBibliography The Grid: An Infrastructure for e-Business and e-Science] David Walker of Cardiff University provides use cases for e-science, and take-up of grid technology, use cases, incl mention of e-Health, e-Business, e-Commerce, e-Learning. Grid uses include:

• Service Providers and Brokers (Trend is towards network-based computing paradigm. Nodes offer different sets of computing services with known advertised interfaces. Software is increasingly seen as a “pay-as-you-go” service rather than a product that you buy once computational economies. Web services important in architecture of the Grid.)
• Use Case 1: Utility Computing (Access the power of a remote computer from user’s desktop. Used to run “canned” applications provided on remote computer. End users may be provided with an API or job submission/management tools. Usually a fee is charged. Quite a simple use of the Grid.)
• Utility Computing: Advantages (End user doesn’t have to install, maintain, or update application. Service provider has low user support costs, and there is less likelihood of the code being pirated. Simple business model. Also works for data and storage.)
• Utility Computing: Issues (Can the end user trust the results returned by the service? (trust, reputation) Should the end user be allowed to execute their own applications on the remote machine? (trust, reputation) If there are several remote resources all providing the same service, which one should an end-user use (discovery, negotiation, and markets).)
• Use Case 2: Enterprise Integration (A distributed organisation wants to make all its compute resources (cycles, data, storage) accessible to all its members. Large companies are often interested in this. Assumes everyone in the organisation is trusted. Corresponds to a simple mini-grid.)
• Enterprise Integration: Advantages (Reduce total cost of ownership. Improve productivity. Extend capability. Reduce design costs Reduce time to market.)
• Enterprise Integration: Issues (Need some form of access control – not all members of the organisation should have access to all resources. Need some form of scheduling so that most important tasks have priority, and resources are accessed fairly.)
• Use Case 3: Virtual Organisations (Many tasks requiring collaboration and resource sharing that spans organisational boundaries. Need mechanisms for controlling access and ensuring security. Same organisations my co-operate on one project and compete on another. VO is also called an “extended enterprise”)
• Example of an Extended Enterprise: GECEM (GECEM: Grid-Enabled Computational Electromagnetics. Partners are BAE Systems, HP, Singapore Institute of HPC, Swansea and Cardiff universities. Partners form a globally-distributed extended enterprise.)
• Slides about CEM
• Why use the grid (Industrial and academic partners form an “extended enterprise” in which resources are intrinsically distributed, and only partially shared. Partners may be prepared to share data, but not the hardware and proprietary software that produces the data.)
• Issues in Remote Execution (Performance and resilience. Mainly network issues. Security. Would like to migrate code to remote resource, execute it, and return results with minimum risk of unauthorised interference.)
• The Output (Status results are returned to the client throughout execution. Results of CEM simulation are returned to client and visualised.)
• e-Health: electronic patient records, distributed and/or remote diagnosis, collaborative surgical planning.
• e-Business: streamline, distribute, and enhance business processes.
• e-Commerce: use the Grid as a marketplace for both traditional and innovative goods and services.
• e-Learning: remove barriers to education and training.

Short/Medium/Long term expectations of the Grid

1. The [wiki:RequirementsBibliography IAP document] page 6 gives a medium term view of what the Grid could be used for and has some implicit requirements (see notes in [wiki:RequirementsBibliography Bibliography] ).

2. [wiki:RequirementsBibliography The Grid: An Infrastructure for e-Business and e-Science] David Walker of Cardiff University provides use cases for e-science, and take-up of grid technology, use cases, incl mention of e-Health, e-Business, e-Commerce, e-Learning.

Use Case writing references

Cockburn, Alistair, "Structuring Use Cases with Goals", Journal of Object-Oriented Programming, Sep-Oct, 1997 and Nov-Dec, 1997. Also available on http://alistair.cockburn.us/crystal/articles/sucwg/structuringucswithgoals.htm

Malan, R. and D. Bredemeyer, "Functional Requirements and Use Cases", June 1999. http://www.bredemeyer.com/pdf_files/functreq.pdf

Malan, R. and D. Bredemeyer, "Use Case Action Guide", April 2000. http://www.bredemeyer.com/pdf_files/UseCase_Template.PDF

Larmen, Craig, "Use-case model: writing requirements in context" from Applying UML and Patterns—An Intro to OOA/D and Iterative Development 2005 http://www.craiglarman.com/book_applying_2nd/06-use%20cases.pdf