1. Globus Computing Infrustructure Software Globus Toolkit 1-2

2. Grid computer software infrastructure • Primary objective: to makes a seamless environment for users to access distributed resources. • Key aspects: • Secure envelope – over all transactions • Single sign-on – being able to access all available resources after providing credentials ONCE • Data Management • Information services - providing characteristics of resources and their status (including dynamic load) • APIs and services that enable applications themselves to take advantage of Grid platform • Convenient User Interfaces (??) 1-2

3. Globus Project • Open source software toolkit developed for Grid computing. • Roots in I-way experiment – led by Ian Foster • Work started in 1996. • Now up to Version 5 • Reference implementations of Grid computing standards. • Defacto standard for Grid computing and one of the most influential projects 1-2

4. Globus Toolkit • “Toolkit” of services and packages for creating basic grid computing infrastructure. One may use parts of the toolkit as needed. • Five major parts: • Common run time - Libraries and services • Security - Components to provide secure access • Execution management - Executing, monitoring and management of jobs • Data Management - Discovery access and transfer of data • Information - Discovery and monitoring of resources and services 1-2

5. Globus Toolkit Version • Version 1 essentially a research prototype not widely used • Version 2 widely used - not web-service based • Version 3 web service based but not widely accepted because of the way services were implemented and non-robustness • Version 4 is web-service based. Some non-web services code exists from earlier versions (legacy) or where not appropriate to change to web-service based (for efficiency, etc.). • Version 5 returned to non-web service approach of version 2. • We are using Globus Version 4.0 as it is mature, widely used, and we did not want to incur new software problems in class. 1-2

6. Timeline of Globus Toolkit Globus 5.0.4 Globus 5.0.0 2011 1-2

7. G T 4 Delegation Service Community Scheduler Framework [contribution] Python WS Core [contribution] C WS Core G T 3 CommunityAuthorization Service OGSA-DAI [Tech Preview] WS Authentication Authorization Reliable File Transfer Java WS Core Grid Resource Allocation Mgmt (WS GRAM)‏ Monitoring & Discovery System (MDS4)‏ G T 2 Pre-WS Authentication Authorization GridFTP Grid Resource Allocation Mgmt (Pre-WS GRAM)‏ Monitoring & Discovery System (MDS2)‏ C Common Libraries G T 3 Replica Location Service XIO G T 4 Credential Management Globus Open Source Grid Software Version 4 Web ServicesComponents Non-WS Components Security Data Management Execution Management Information Services CommonRuntime 1-2 I Foster

8. Major Globus 5 changes over version 4 “Most components of GT5 are incremental updates (numerous bug fixes and new features) over their GT4 counter-parts (e.g. GridFTP, RLS, MyProxy, GSI-OpenSSH” Some components taken out: GT4 Java Core, WS-GRAM4, RFT, to be replaced. GRAM implementation -- pre-WS GRAM2 code base and GRAM2 compatibile. NO WEB SERVICE COMPONENTS http://www.globus.org/toolkit/docs/5.0/5.0.0/rn/ 1-2

9. Currently not showing information services in version 5. New Globus crux project will address this. 1-2 http://www.globus.org/toolkit/about.html

10. Some basic Globus components • GSI Grid Security Infrastructure • Provides for security envelop around Grid resources • Uses public key cryptography • GRAM (Globus/Grid Resource Allocation Management)‏ • Globus’ basic execution management component • Used to issue and manage jobs • GridFTP • For transferring files between resources • MDS (Monitoring and Discovery Service)‏ • To discover resources and their status 1-2

11. Security Issues • Has to cross administrative domains. • Need agreed mechanisms and standards. • Focus on Internet security mechanisms, modified to handle the special needs of Grid computing. • Distributed resources must be protected from unauthorized access. 1-2

12. GSI (Grid Security Infrastructure)Globus components for creating security envelop • Requires each user to be authenticated (their identity proved) • Uses public key cryptography (basis of Internet security)‏ • Each user must possess a (digital) certificate, signed by a trusted certificate authority. • Users will also need to be able to give their authority to Grid components to act on their behalf – so-called proxy certificates, see later. • Users generally will also need accounts on resources they intend to use (authorization). 1-2

13. Resource DiscoveryGlobus MDS (Monitoring and Discovery System) • Users might access MDS to discover status of compute resources. In practice, users often know what resources are there but not dynamic load. • MDS might be used by other Grid components such as schedulers. • Still primitive and in research but ideal is to be able to submit a job and the system find the best grid resources for that job across the whole grid 1-2

14. Executing a JobGRAM (Globus or Grid Resource Allocation Management) • Users typically want to submit jobs for execution. • Grid computing environments mostly Linux-based and originally and still commonly accessed through a command line. 1-2

15. Job submission command-line interface • Once you have established your security credentials, to run a simple job you might issue GRAM command: globusrun-ws -submit -c prog1 * where prog1 is executable of job. • Executable needs to be present on compute resource that is to execute it. • Above command does not specify compute resource and hence computer executing globusrun-ws command will execute prog1. 1-2 * Globus 5 command is globusrun (not a web service)

16. GridFTP command to transfer files globus-url-copy \ gsiftp://www.coitgrid02.uncc.edu/~abw/prog1out \ file:///home/abw/ First argument -- source location Second argument -- destination location. In the above case, the file: www.coit-grid02.uncc.edu/~abw/prog1out transferred to home/abw/prog1out on the local computer. 1-2

17. Scenario of User employing Globus services and facilities 1-2

18. Grid portals • Command-line interface a very primitive way of interacting with Grid resources. • Portal offers a higher-level Web based interfaces to accessing and controlling grid resources and to communicate with other members of Virtual Organization 1-2

19. Gridsphere • Gridsphere is a toolkit to build a portal • We are starting with a portal. Next we will use the command line • Later we will have an assignment of building a portal 1-2

20. Proxies • To use many services, you are required to have a proxy certificate (a proxy), derived from your user certificate. • Proxies enables resources to be accessed on user’s behalf. • Proxies are part of Grid security infrastructure, discussed later in course. • A credential management service called myProxy is used to hold proxies • Usually, Gridsphere automatically obtains a proxy from the myProxy server for you when you log in. 1-2

21. Proxy management tab 1-2

22. Questions 1-2.22

23. Quiz Question: What is meant by "single sign-on"? (a) Allowing only one person to sign onto a computer (b) Not allowing a person to log onto a computer more than once in any one period (c) A mechanism in which a user does not need to sign again to acquire additional resources. (b) None of the other answers 1-2.23

24. Question: What is authentication and what is authorization? What’s the difference? 1-2.24

25. Question: What does GRAM do? 1-2.25

26. Question: What does MDS do? 1-2.26

27. Question: What compoent in the Globus toolkit provides the means to transfer files? 1-2.27

28. Discussion Question Is it possible to use the tradition security method of username/password on a grid? What problems exist for this method? 1-2.28