1. 6/12/99 Java GrandeT. Haupt1 The Gateway System This project is a collaborative effort between Northeast Parallel Architectures Center (NPAC) Ohio Supercomputer Center (OSC) Aeronautical Systems Center (ASC) MSRC

2. 6/12/99 Java GrandeT. Haupt2 Goals To provide a problem-oriented interface (a Web portal) to more effectively utilize HPC resources from the desktop via the Web browser. This “point & click” view hides the underlying complexities and details of the HPC resources and creates a seamless interface between the user’s problem description on his/her desktop system and the heterogeneous computing resources These HPC resources include supercomputers, mass storage systems, databases, workstation clusters, collaborative tools, and visualization servers.

3. 6/12/99 Java GrandeT. Haupt3 Design Issues Support for a seamless access (security) Support for distributed, heterogeneous Back-End services (HPCC, DBMS, Internet,...) managed independently from Gateway Variable pool of resources: support for discovery and dynamical incorporation into the system Scalable, extensible, low-maintenance Middle Tier Web-based, extensible, customizable, self-adjusting to varying capacities and capabilities of clients (humans, software and hardware) front end

4. Towards a complete solution... Problem description : I need to model the surface damage due to the impact of laser to harden the material bulk. I need access to models including material bulk properties and interaction with intense electromagnetic fields. Task description: I need 64 nodes of SP-2 at Argonne to run my MPI-based executable “a.out” you can find in “/tmp/users/haupt” on marylin.npac.syr.edu. In addition, I need any idle workstation with jdk1.1 installed. Make sure that the output of my a.out is transferred to that workstation Middle-Tier: map the user’s task description onto the resource specification; this may include resource discovery, and other services Resource Specification Resource Allocation: run, transfer data, run

5. 6/12/99 Java GrandeT. Haupt5 Services User Modules Back-End Resources Front-End Back-End services comprise Tier 3. Distributed, object-based, scalable, and reusable Web server, Object broker and Resource Manager Middleware forms Tier 2 Three-Tier Architecture Tier 1 is a high-level, browser-based Front End for visual programming (including selection of applications, generation of input data sets, specification of resources, post-processing and visualizations)

6. Target Architecture Middle-Tier Resource Specification Abstract Task Specification CTA specific knowledge databases Visual Authoring Tools User and Group Profiles Resource Identification and Access Visualizations Collaboration WebFlow Back-End Resources Problem Solving Environment

7. 6/12/99 Java GrandeT. Haupt7 Portal Page Provides initial access to the Gateway. After mutual authentication of the user and the Gateway server, creates a user context, and returns a (signed) control applet.

8. 6/12/99 Java GrandeT. Haupt8 User and Group Profile Controls the user/group environment –file access –job monitoring –... Allows for customization –preferences –users with disabilities –... History of actions Scientific notebook

9. 6/12/99 Java GrandeT. Haupt9 Control Applet The control applet is responsible for maintaining the session, and direct communication with the middle-tier. Direct communication is the most efficient, but since it is buried into an applet, this mechanism is not readily customizable. The generic services, such as file service (upload, download, edit, copy, move, delete) and job services (show current jobs/show queues/kill jobs) will be supported this way. [combination of the user context and a query] The Gateway will also support a non-direct communication with the middle-tier through servelts.

10. 6/12/99 Java GrandeT. Haupt10 Screen Dump of the Control Applet

11. 6/12/99 Java GrandeT. Haupt11 Application Domain DataBases PSE Example: CCM Ken Flurchick, http://www.osc.edu/~kenf/theGateway 1. Enter the Gateway system 2. Define your problem 3. Identify resources (software and hardware) 4. Create input file 5. Run your application 6. Analyze results

12. 6/12/99 Java GrandeT. Haupt12

13. 6/12/99 Java GrandeT. Haupt13 Selecting a Predefined Task

14. 6/12/99 Java GrandeT. Haupt14 Visual Authoring Tools Allows for composition of the computational task from components (reusable modules) Different tools to support various programming models such as data parallel, task parallel, data flow, object oriented No assumption on granularity Metadata about components and support for archiving and mining the components Support for instrumentation and steering

15. T. Haupt15 Example: Data Flow

16. 6/12/99 Java GrandeT. Haupt16 Example: DARP

17. Example of a portal Navigate and choose an existing application to solve the problem at hand. Import all necessary data. Retrieve data Pre/post-processing Run simulations Select host Select model Set parameters Run

18. Processing Task Specification XML A visual representation is converted into a XML document XML service Web Server save parse ApplContext Generates Java code to add modules to ApplContext Publishes IOR Front-End Applet Middle-Tier

19. 6/12/99 Java GrandeT. Haupt19 Other toolboxes Visualizations Collaboration Scientific notebook...

20. 6/12/99 Java GrandeT. Haupt20 CORBA Based Middle-Tier Mesh of WebFlow Servers implemented as CORBA objects that manage and coordinate distributed computation. Front End Gatekeeper Authentication Authorization

21. User 1User 2 Application 1 Application 2 App 2App 1 WebFlow Server WebFlow server is given by a hierarchy of containers and components WebFlow server hosts users and services Each user maintains a number of applications composed of custom modules and common services WebFlow Services

22. T. Haupt22 WebFlow Context Hierarchy Master Server (Gatekeeper) Slave Server User Context Application Context Module Slave Server Proxy

23. 6/12/99 Java GrandeT. Haupt23 Module functionality May act as a client for a back-end service such as Globus GRAM or a database May invoke other Gateway Middle Tier services such as File Services or Resource Discovery May implement the desired functionality internally (say, in Java) [thus not a proxy] May interact with other modules and the Front End through events

24. 6/12/99 Java GrandeT. Haupt24 Services User Modules Browser based Front-End Middle-Tier modules serve as proxies of Back-End Services Browser based Front-End User Space Definition and Task Specification Metacomputing Services Back-End Resources

25. 6/12/99 Java GrandeT. Haupt25 Back End Services Access to HPCC (via Globus) Access to distributed databases (via JDBC) Access to mass storage Access to the Internet resources Access to desktop application and local data Access to code repositories

26. 6/12/99 Java GrandeT. Haupt26 WebFlow over Globus In order to run WebFlow over Globus there must be at least one WebFlow node capable of executing Globus commands, such as globusrun Jobs that require computational power of massively parallel computers are directed to the Globus domain, while other jobs can be launched on much more modest platforms, such as the user’s desktop or even a laptop running Windows NT. Bridge between WebFlow and Globus

27. SECIOP Security Model (Keberos) Front End Applet SECIOP authentication & authorization Gatekeeper delegation HPCC resources GSSAPI Layer 1: secure Web Layer 2: secure CORBA Layer 3: Secure access to resources Policies defined by resource owners