-------------------------------------------------------------------- SAGA Use Case Template: ======================= Name of use case: MNT - Digital Terrain Model Contact (name and address): philippe@lifc.univ-fcomte.fr Authors (if different form contact) Gerard Vidal (ENS Lyon - France) 1. General Information: ----------------------- This section consists of check-boxes to provide some context in which to evaluate the use case. 1.1 Which best describes your organisation: Industry [ ] Academic [X] Other [ ] Please specify: ................................... 1.2 Application area: Astronomy [ ] Particle physics [ ] Bio-informatics [ ] Environmental Sc. [X] Image analysis [ ] Other [ ] Please specify: ................................... 1.3 Which of the following apply to or best describe this use case Multiple selections are possible, please prioritize with numbers from 1 (low) to 5 (high): Database [ ] Remote steering [ ] Visualization [3] Security [ ] Resource discovery [ ] Resource scheduling [ ] Workflow [ ] Data movement [3] High Throughput Computing [ ] High Performance Computing [5] Other [ ] Please specify: ................................... 1.4 Are you an: Application user [ ] Application developer [ ] System administrator [ ] Service developer [ ] Computer science researcher [X] Other [ ] Please specify: ................................... 2. Introduction: ---------------- 2.1 Provide a paragraph introduction to your use case. Background to the project is another alternative. (E.g. 100 words). This parallel application is based on a stereo vision algorithm. We focus on the particular stereo vision problem of accurate Digital Elevation Models (DEMs) reconstruction from a pair of images of the SPOT satellite. The input data consists in two images of a particular region taken from different points of view. From these images, we extract the three-dimensional information by finding couples of corresponding points and computing 3D coordinates using camera information. The input data size may be very large especially from satellite imagery which produces 6000 x 6000-pixel images, involving important computation times as well as very large memory demand. 2.2 Is there a URL with more information about the project ? http://graal.ens-lyon.fr/~gridasp/aci_appli2.html 3. Use Case to Motivate Functionality Within a Simple API: ---------------------------------------------------------- o Source code of DEM is not distributed for customer installation. They just access a DEM server to submit their problem. o Datas needed for a job submission are six files plus scalar and boolean values. o job submission may be synchronous : the customer send a set of parameters and check if the result is relevant. o job submission may be ssynchronous : the customer send several sets of parameters and compare a posteriori the results at the end of the jobs executions. o result of a job submission is an image file. 4. Customers: ------------- Customers are geologists without computer science experience. They mesure the geological evolution of an area, somethime in place with just a laptop and GSM connection. They need to remotly access the server. 5. Involved Resources: ---------------------- 5.1 List all the resources needed: e.g. what hardware, data, software might be involved. - hardware : parallel machine / cluster, nodes with large memory - software : MPI, Diet, Corba, DEMsolver - visualisation tools (raster files, mpeg player) 5.2 Are these resources geographically distributed? yes, in case of multiple submissions 5.3 How many resources are involved in the use case? E.g. how many remote tasks are executing at the same time? one per job submission. Usually less than ten if there are mutliple submissions. 5.4 Describe your codes and tools: what sort of license is available, e.g. open or closed source license; what sort of third party tools and libraries do you use, and what is their availablility; do you regularly work from source code, or use pre-compiled applications; what languages are your applications developed in (if relevant), e.g. Fortran, C, C++, Java, Perl, or Python. DEM code is not distributed, just installed on three servers. It is written in C / MPI 5.5 What information sources do you require, e.g. certificate authorities, or registries. no 5.6 Do you use any resources other than traditional compute or data resources, e.g. telescopes, microscopes, medical imaging instruments. no 5.7 How often is your application used on the grid or grid-like systems? [ ] Exclusively [ ] Often (say 50-50) [x] Ocassionally on the grid, but mostly stand-alone [ ] Not at all yet, but the plan is to. 6. Environment: --------------- Provide a description of the environment your scenario runs in, for example the languages used, the tool-sets used, and the user environments (e.g. shell, scripting language, or portal). access to DEM is available through a servlet in a portal. 7. How the resources are selected: ---------------------------------- 7.1 Which resources are selected by users, which are inherent in the application, and which are chosen by system administrators, or by other means? E.g. who is specifying the architecture and memory to run the remote tasks? no resources are selected by users, everything is done by the execution plateform 7.2 How are the resources selected? E.g. by OS, by CPU power, by memory, don't care, by cost, frequency of availability of information, size of datasets? by performances evaluation, CPU and network load, Diet features. 7.3 Are the resource requirements dynamic or static? dynamic 8. Security Considerations: --------------------------- 8.1 What things are sensitive in this scenario: executable code, data, computer hardware? I.e. at what level are security measures used to determine access, if any? executable code 8.2 Do you have any existing security framework, e.g. Kerberos 5, Unicore, GSI, SSH, smartcards? no 8.3 What are your security needs: authentication, authorisation, message protection, data protection, anonymisation, audit trail, or others? data protection + authentification 8.4 What are the most important issues which would simplify your security solution? Simple API, simple deployment, integration with commodity technologies. simple API 9. Scalability: --------------- What are the things which are important to scalability and to what scale - compute resources, data, networks ? compute resource, already tested on a T3E with 256 nodes. 10. Performance Considerations: ------------------------------- Explain any relevant performance considerations of the use case. Data must not be transfered several times 11. Grid Technologies currently used: ------------------------------------- If you are currently using or developing this scenario, which grid technologies are you using or considering? Diet 12. What Would You Like an API to Look Like? -------------------------------------------- Suggest some functions and their prototypes which you would like in an API which would support your scenario. ... 13. References: --------------- List references for further reading. ... --------------------------------------------------------------------