Friday 19 July 2013

080230051 Grid Computing anna university syllabus 2 marks and 16 marks questions and answers

Final Year Computer Science and Engineering, 7th Semester

Subject Code & Name: 080230051 /  Grid Computing

UNIT 1 INTRODUCTION

1. What are computational grids?
A computational grid is hardware and software infrastructure that provides dependable, consistent, pervasive and inexpensive access to high-end computational capabilities.

2. What is the role of a grid portal?
Grid portal provide capabilities for Grid Computing resource authentication, remote resource access, scheduling capabilities, and monitoring status information.

3. What are the business benefits in Grid Computing?
·         Acceleration of implementation time frames in order to intersect with the anticipated business end results.
·         Improved productivity and collaboration of virtual organizations and respective computing and data resources.
·         Allowing widely dispersed departments and business to create virtual organizations to share data and resources.

4. What are the business areas needs in Grid computing?
·         Life Sciences
·         Financial services
·         Higher Education
·         Engineering Services
·         Government
·         Collaborative games

5. List out the Grid Applications:
·         Application partitioning that involves breaking the problem into discrete pieces
·         Discovery and scheduling of tasks and workflow
·         Data communications distributing the problem data where and when it is required
·         Provisioning and distributing application codes to specific system nodes
·         Autonomic features such as self-configuration, self-optimization, self-recovery and self-management

6. Define Scheduler:
Schedulers are types of applications responsible for the management of jobs, such as allocating resources needed for any specific job, partitioning of jobs to schedule parallel execution of tasks, data management, event correlation and service-level management capabilities.

7. What are the areas we need scheduler?
·         Advanced resource reservation
·         Service –level agreement validation and enforcement
·         Job and resource policy management and enforcement for best turnaround times within the allowable  budget constraints
·         Monitoring job execution and status
·         Rescheduling and corrective actions of partial failover situations

8. What is the use of resource broker?
The resource broker provides pairing services between the service requester and the service provider.


9. What is the use of load balancing?
To avoid processing delays and over commitment of resources.

10. List out the grid portal capabilities:
·         Querying databases or LDAP servers for resource-specific information
·         File transfer facilities such as file upload, down load, integration with custom software, and so on
·         Manage job through job status feedbacks.
·         Allocate the resources for the execution of specific tasks.
·         Security management
·         Provide personalized solutions

11. What are the uses of Integrated Solutions?
The integrated solutions are a combination of the existing advances middleware and application functionalities, combined to provide more coherent and high performance results across the grid Computing environment.

12. What are the areas are difficult to implement in Grid Computing Infrastructure?
A Grid computing infrastructure component must address several potentially complicated areas in many stages of the implementation. These areas are
·         Security
·         Resource management
·         Information services
·         Data management

13. Define grid computing:
·         Grid concept is defined as control sharing of resources and problem solving in dynamic, multi institutional virtual organization.
·         Grid computing is a open standard.
·         It has well defined policies and conditions to solving the problem.

14. What are the grid applications?
·         Scheduler
·         Resource broker
·         Grid portals
·         Load Balancing
·         Integrated solutions

15. What is meant by grid infrastructure?
Grid infrastructure is a complex combination of a number of capabilities and resources identified for the specific problem and environment being addressed. It forms the core foundations for successful grid applications.

16. List some grid computing toolkits and frameworks?
·         Globus Toolkit
·         Globus Resource Allocation Manager(GRAM)
·         Grid Security Infrastructure(GSI)
·         Information Services
·         Legion
·         Condor and Condor-G
·         NIMROD
·         UNICORE
·         NMI

17. Write short notes on Legion.
Legion is a middleware project initiated by University of Virginia, is object based meta system software for grid applications. The goal of legion project is to promote the principled design of distributed system software by providing standard object representations for processors, data systems, file system and so on.

18. Define some important characteristics of legion system:
·         Everything is an object
·         Classes manage their own instances
·         Users can provide their own classes
·         Core objects implement common services

19. Define short notes on GRAM:
GRAM provides resource allocation, process creation, monitoring, and management services. The most common use of GRAM is the remote job submission and control facility. GRAM simplifies the use of remote systems.

20. What is mean by middleware?
Middleware is software that connects two or more other wise separate applications across the Internet or local area network. Middleware makes resource sharing seem transparent to the end user, providing capabilities, consistency, security and privacy.

21. What is the major difference between condor and condor G?
Condor is a tool for harnessing the capacity of idle workstations for computational tasks. Condor-G is a derivative software system, which leverages the software from Condor and Globus with major focus on the job management services for grid applications. This is a combination of interdomain resource management protocols of globus with the intra domain resource management methods of Condor.

22. How do p2p environments differ from grid environments?
The major difference between Grid computing and p2p computing is centered on the following notable points:
·         They differ in their target communities. Grid communities can be small with regard to number of users, yet will yield a greater applications focus with a higher level of security requirements and application integrity.
·         On the other hand, the p2p systems define collaboration among a larger number of individuals and/or organizations, with a limited set of security requirements and a less complex resource-sharing topology.

23. What is the primary objective of GGF?
The GGF’s primary objective is to promote and support development, deployment and implementation of grid technologies and applications via creation and documentation of best practices-specifications, use cases, architecture and implementation guidelines.

24. What are the best goals of GGF?
The basic goals of the GGF are to
·         Create an open process for the development of grid agreements and specifications
·         Create grid specifications, architecture documents, and best practice guidelines.
·         Manage and version controls the documents and specifications
·         Handle intellectual property policies
·         Provide a forum for information exchange and collaboration.

25. What are the major areas of GGF?
·         Application and programming environments
·         Architecture
·         Data
·         Information systems and performance
·         Peer-to-peer: Desktop grids
·         Scheduling and resource management
·         Security

26. What are the high-level services included in Globus toolkit?
·         Globus Resource Allocation Manager(GRAM)
·         Grid Security Infrastructure(GSI)
·         Information Services



27. List out some of the Grid Computing Toolkits:
·         Globus
·         Legion
·         Condor and Condor-G
·         Nimrod


28. List out the core objects defined by the Legion system:
·         Host Objects
·         Vault Objects
·         Binding Objects
·         Implementation Objects

29. What are the scheduling algorithms used in Nimrod-G?
·         Cost Optimization
·         Time Optimization
·         Cost-time Optimization
·         Conservative time strategy

30. How many teams in NMI?
·         Grid Research Integration Deployment
·         Support(GRIDS)Center

31. List out the different layers of the Tera Grid architecture:
·         Base Grid Services Layer(Resource Layer)
·         Core Grid Services(Collective Layer)
·         Advanced Grid Services

32. Define Cluster computing:
Cluster is local to the domain and constructed to solve inadequate computing power. It is related to the pooling of computational resources to provide more computing power by parallel execution of the workload.

33. What are the basic principles followed by the autonomic computing system?
·         Self-configuring
·         Self-optimizing
·         Self-healing
·         Self-protecting

34. What are the essential characteristics of on- demand business?
·         Responsive
·         Variable
·         Focused
·         Resilient

35. List out the characteristics of DOE:
·         Most of the DOE projects are widely distributed among collaborators and non-collaborators. It requires a cyber infrastructure that supports the process of distributed science with sharable resources including expensive and complex scientific instruments.
·         All of the science areas need high-speed networks and middleware to discover, manage and access computing and storage systems.

36. What is the role of the grid computing organization?
·         Organizations developing grid standards and best practices guidelines.
·         Organizations developing grid computing toolkits, frameworks and middleware solutions.
·         Organizations building and using grid-based solutions to solve their computing, data, and network requirements.
·         Organizations working to adopt grid concepts into commercial products, via utility computing and business on demand computing.

37. What are the components are defined by the Nimrod architecture?
·         Nimrod-G clients, which can provide tools for creating parameter sweep applications, steering and control monitors, and customized end-user applications and GUIs
·         The Nimrod-G resource broker, which consists of a Task farming engine(TFE), a scheduler that performs resource discovery, trading and scheduling features, a dispatcher and actuator, and agents for managing the job on the resources.

38. What are the essential capabilities of on-demand business?
·         Integrate
·         Virtualization
·         Automation
·         Open Standard

39. What are the important functionalities provided by the management protocols in protocol layer architecture?
·         Negotiating access to a shared resource is paramount. These negotiations can include the requirements on quality of service, advanced reservation, scheduling and other key operational factors.
·         Performing operation on the resource, such as process creation or data access, is also a very important operational factor.
·         Acting as the service/resource policy enforcement point for policy validation between a user and resource is critical to the integrity of the operations.
·         Providing accounting and payment management functions on resource sharing is mandatory.

40. Give the different layers of grid architecture.
·         Fabric Layer: Interface to local resources
·         Connectivity Layer: Manages Communications
·         Collective Layer: Coordinating Multiple Resources
·         Application Layer: User-Defined Application.



Part –B
1. Explain in detail about virtual organization.(16)
2. Write about the scope of grid computing in business areas. (16)
3. Explain some of the grid application and their usage patterns. (16)
4. Write short notes on.(16)
a) Schedulers
b)Resource broker
c) Load balancing
d) Grid portals
5. What are the data and functional requirements of grid computing? .(16)
6. Explain briefly about grid infrastructure. .(16)
7. a) Explain about the organization developing grid standards and best practices
guidelines (8)
b) Explain about the organization working to adopt grid concepts into
commercial products.(8)
8. Discuss briefly about organization building and using grid based solution to
solve their computing data and network requirements. .(16)
9. Write notes on organizations developing grid computing toolkits frameworks
and middleware solution. .(16)
10. Explain the layered architecture of grid with a neat diagram. (16)
11. Describe about the relation of grid architecture with other distributed
technologies. .(16)
12. Write notes on
Autonomic computing (4)
BOD and infrastructure virtualization (4)
Service oriented architecture and grid (4)
Semantic grids (4)

UNIT-2 GRID COMPUTING ROADMAP

1. Define SOA.
Service oriented architecture is intended to define loosely coupled and interoperable services applications, and to define process for integrating these interoperable components. In SOA, the system is decomposed into a collection of network-connected components. Applications and resources within a SOA shouldn’t be built as a tightly coupled monolithic model. Rather; these applications are composed dynamically from the deployed and available services in the network.

2. What are the fundamental components of SOAP specification?
·         An envelope that defines a framework for describing message structure.
·         A set of encoding rules for expressing instances of application-defined data types.
·         A convention for representing remote procedure (RPC) and responses.
·         A set of rules for using SOAP with HTTP.
·         Message exchange patterns (MEP) such as request-response, one-way and peer-topeer
·         conversations.



3. Define SOAP.
SOAP is a simple and lightweight XML-based mechanism for creating structured data packages that can be exchanged between network applications. SOAP provides a simple enveloping mechanism and is proven in being able to work with existing networking services technologies such as HHTP.SOAP is also flexible and extensible. SOAP is based on the fact that it builds upon the XML info set.

4. What are the options related to processing in the SOAP process model?
There are two options related to processing.
·         If the SOAP header is targeted to this node and specifies a “must understand” flag set to “true”, then the processing node must process that header.
·         If there is no such requirements (that is “must understand” flag is not set),it is up to the preprocessing node to decide on the processing of the message. Once the processing is completed, the message will be directed to the next node. The decision on the next node selection is not specified by the SOAP specification. Therefore it is now the choice of the processing node to make such decision.

5. How does the process of relaying is done in SOAP headers?
A header can have a “relay” attribute value (i.e. true or false)to indicate that nonprocessed headers get forwarded to the next node. The default value is “false”. This indicates a SOAP node, which is targeted by this header, will not forward this header to the next node.

6. What are the characteristics of the SOAP feature?
·         A unique name used to identify the feature and its properties. This enables us to identify whether a SOAP node supports a specific feature.
·         A set of properties associated with a feature that can be used to control, constrain, or identify a feature.

7. What are the two important mechanisms for implementing the SOAP features?
·         SOAP header blocks:
In this kind of implementation SOAP header blocks are used to specify the feature .These headers are processed by the SOAP nodes. SOAP node in order to process an individual message. The most common eg of such a feature is the security features as defined by WS-security specifications.
·         SOAP binding protocol:
The features are directly implemented in the protocol binding level. For e.g., a binding extension to support the SOAP over SSL protocol.

8. Define MEP.
It is one of the special type of SOAP feature. A SOAP MEP is a template that establishes a pattern for the exchange of message between SOAP nodes. Some of the examples of SOAP include request/response, one way, peer-to-peer conversation, and so on.

9. What is SOAP module?
The combined syntax and semantics of SOAP headers are known as SOAP module. A SOAP module realizes one or more SOAP features. This enables to specify a more general purpose concepts such as a secure purchase order, the purchase order of MEP,the security feature and more.

10. Define WSDL.
WSDL is an XML Info set based document, which provides a model and XML format for describing web services. This enables services to be described and enables the client to consume these services in a standard way without knowing much on the lower level protocol exchange binding including SOAP and HTTP. This high level abstraction on the service limits human interaction and enables the automatic generation of proxies for web services, and these proxies can be static or dynamic. It allows both document and RPC-oriented messages.

11. List out the vision behind Global XML Architecture:
·         Providing standards-based and interoperable protocol definitions.
·         Reducing development efforts by separating infrastructure protocols from application and transport protocols.
·         Providing open standards-based designs for interoperable messaging across multiple vendors.

12. Major building blocks identified by GXA:
·         Message-level security.
·         Exchanging transaction-aware messages.
·         Message exchange coordination among participants.
·         Reliable message exchange patterns.
·         Message routing and referral processes.
·         Addressing mechanisms to dispatch messages to the intended party.
·         Service and message policies for proper message handling.
·         Attachments to foreign bodies that won’t fit with regular messages.
·         Metadata information exchange.
·          

13. What is WS-Federation?
WS-Federation defines mechanisms that are used to enable identify, attribute, authentication and authorization federation across different trust environments.

14. Mention the two type of message encoding used in WSDL 1.1.
The two types of message encoding are literal encoding and SOAP encoding. Literal encoding specifies that the messages will be constructed using XML schema “literal”, and SOAP encoding occurs according to the SOAP –encoding rules “encoded” defined in th SOAP specification.

15. What is mean by “target Resource”?
The “target Resource” is an attribute of a service element with a URI value representing the resource URI.

16. What is WS-Secure Conversation?
This specification defines extensions that build on WS-Security to provide secure communication. The mechanisms provided include provisions for establishing and sharing security contexts and deriving session keys from security contexts.

17. What is WS-trust?
WS-Trust deals with different aspects of secure token services including how to request a token and the issuing of tokens in a trusted manner. This issuance of tokens must be secure and built on top of WS-Security. The secure token services can be a contact point for secure negotiation through delegation and impersonation.

18. What is WS-Addressing?
WS-Addressing provides transport-neutral mechanisms to address Web services and
messages. This capability is provided by the specification using two constructs:
·         A flexible and extendable end-point reference description model.
·         A set of SOAP message header and rules to map the above reference elements to
the header elements.

19. What are the uses of XML Schema?
·         Service Publication and Discovery.
·         Security
·         Tools.

20. What do you mean by Grid Services?
Grid services are stateful Web services. The service itself maintains some state information and it exposes a set of standard interfaces to enable interactions with its client.

21. What is XM Data Model?
The core of Web services is the XML data model or the XML information set. This is defined by the W3C and forms the core of all XML specifications including SOAP and WSDL. This common base allows creation of adaptable tools and XML processors.

Part –B

1. Explain briefly about SOA.(16)
2. Explain briefly about Web service architecture .(16)
3. Explain in detail about SOAP.(16)
4. What are the service message description mechanism available?. Explain. .(16)
5. Explain briefly about WSDL. (16)
6. Discuss in detail about global XML Architecture vision.(16)
7. Discuss in detail about web service and grid service.(16)
8. Explain in detail about Basic Profile guidelines.(16)







UNIT-3 GRID COMPUTING TECHNOLOGICAL VIEW POINTS

1. What are the major goals of OGSA?
·         Identify the use cases that can drive the OGSA platform components.
·         Identify and define the core ODSA platform components.
·         Define hosting and platform-specific bindings.
·         Define resources models and resource profiles with interoperable solutions.

2. What are the purposes of use cases?
·         To identify and define core platform functionalities.
·         To define core platform components based on the functionality requirements.
·         To define the high-level requirements on these core components and identify their interrelationships.

3. What do you mean by Commercial Data Center (CDC)?
Data centers are common in most of the big enterprises in order to consolidate the huge number of servers to reduce the total cost of ownership. It play a key role in the outsourcing business where major business outsource their IT resource management to concentrate on their core business competence and excellence. These data centers are required to manage a huge number of IT resources (servers, storages, networks).It provides resource sharing capability across virtual organization.

4. What is National Fusion Collaboratory (NFC)?
The NFC project defines a virtual organization devoted to fusion research and provides the “codes” developed by this community to end users. The fusion community decided to adopt the ASP model known as “network services model”, where the “code” is maintained by the service provider and make accessible to the remote centers. This eliminates burden on the end users but adds some QOS requirements on the SP, including executing the code, executing within a certain time frame, and produce the results with accuracy.

5. What are the layers of OGSA architectural organization?
·         Native platform services and transport mechanism.
·         OGSA hosting environment.
·         OGSA transport security.
·         OGSA infrastructure (OGSI).
·         OGSA basic services (meta-OS and domain services).

6. What are the two dimensions to state the nature of a web services?
·         The service is maintaining its state information. These are normally classified as application state and in the case of grid service it directly maps to the state of the resource.
·         The interaction pattern between the client and the service can de stateful. There are numerous architecture styles and programming models for defining these interactions including BPEL4WS and REST.

7. What are the core requirements for describing web services based on OGSI?
·         The ability to describe the interface inheritance.
·         The ability to describe additional information elements (state data/attributes/properties)
with the interface definitions.

8. What do you mean by the term flattening?
Basically,GWSDL extensions are to be transformed to WSDL.All the “extends” port types and their operations, which are brought down to a single most derived portType. This process is called “flattening” of the interface hierarchy to the most derived type.

9. What are the SDE attributes of OGSI schema type for service data?
The new OGSI schema type contains seven predefined attributes, including name, type, minOccurs, maxOccurs, modifiable, mutability, and nilable.These are standard XSD types with the exception of the “mutability” attribute. This is further defined by OGSI as an enumerated type, with the values of “static”, “constant”, “extendable” and “mutable”.

10. What are the lifetime properties of OGSI specification?
·         This time from which the contents of this element are valid (ogsi: goodFrom).
·         This time until which the contents of this element are valid (ogsi:goodUntil).
·         This time until which this element itself is available (ogsi: availableUntil).

11. What is soft-state lifetime management?
The soft-state lifetime management approach is a recommended method in the grid service life-cycle management process. Every grid service has a terminated time set by the service creator. This soft-state lifecycle is controlled by appropriate security and policy decisions of the service and the service has the authority to control this behavior.

12. What are Grid service Interfaces?
The grid service interfaces and their associated behaviors are described by the OGSI specification. This OGSI interfaces are classified into three sets of interfaces based upon their functionality. They are
·         OGSI core
·         Notification
·         Service groups.

13. What are the rules for handling the services of the set operation on service data?
The rules are as follows:
·         The service Data must be modifiable; the SDE-modifiable attribute must be “true”.
·         The service Data mutability attribute should not be “static” or “constant”.
·         If the service Data mutability attribute is “extendable” the set operation must append the new SDE values to the existing SDE values.
·         If the service Data mutability attribute is “mutable” the set operation must replace the existing SDE values with the new SDE values.
·         The SDE values, “append” and “replace” must adhere to the minOccurs and maxOccurs attributes on SDE values.

14. What is “handle resolver”?
Handle resolving is a standard mechanism to resolve a GSH into a GSR. This is an optional feature based on the Handler solver port Type. A grid service instance that implements the Handler solver port Type is called a “handle resolver”.

15. Explain about MembershipContentRule:
Deriving a service from the ServiceGroup portType and utilizing the “MembershipContentRule” service data for the classification mechanisms can create a grouping concept similar to a registry. This “rule” service data is used to restrict the membership of a grid service in the group.

16. What are the two types of clients in Grid Service?
·         Static:
1.      These kinds of clients have plurality of a priori knowledge on the
              runtime binding information.
2.      These are faster but less flexible in operations.
·         Dynamic:
1.      These types of clients ar flexible and they are not bound to any
               predefined artifacts.
2.      These are highly flexible but less efficiencies.

17. Define CMM:
CMM (Common Management Model) is an abstract representation of real IT resources such as disks, file systems, operating systems, network ports and IP addresses.

18. What are the three aspects of manageability in CMM specification?
·         An XML schema (XSD) for modeling the resource manageability information.
·         A collection of manageability port Types.
·         Guidelines for modeling resource.

19. What is service domain?
The OGSA service domain architecture proposes a high level abstraction model to describe the common behaviors, attributes, operations and interfaces to allow a collection of services to function as a single unit.

20. What are the functionalities provided by the service domain components?
·         Service registration and collection
·         Service routing and selection
·         Service interoperation and transformation
·         Flexible service composition
·         Automatic service orchestration

21. What are the various levels of Policy Abstraction?
·         Business Level
·         Domain Level
·         Device Level

Part –B
1. Describe the architecture of OGSA.(16)
2. Explain briefly about commercial data center.(16
3. Explain briefly about NGC.(16)
4. Explain briefly about Commercial grid.
5. What are the OGSA platform components? Write note on each of them. (16)
6. Describe in detail about the inheritance interface diagram.(16)
7. Describe in detail about service data concepts(16)
8. Explain briefly about CMM.(16)
9. What are the OGSA basic services? Explain each of them with necessary
diagrams. .(16)
10.(a) Write notes on policy architecture (8)
(b) Write notes on security architecture (8)
11.(a) Write notes on metering and accounting (8)
(b)Write notes on common distributed logging (4)
(c)Write notes on distributed data access and replication (4).


UNIT – IV SCHEDULING GRID SERVICES

1.What are the functions of static heuristics algorithm?
  • Opportunistic Load Balancing (OLB)
  • User-Directed Assignment (UDA)
  • Fast Greedy
  • Min-min
  • Max-min
  • Greedy
  • Genetic Algorithm (GA)
  • Simulated Annealing (SA)
  • Genetic Simulated Annealing (GSA)

2.What is Dynamic heuristics algorithm?
In an HC system where the tasks to be executed are not known a priori, dynamic schemes are necessary to match tasks to machines, and to compute the execution order of the tasks assigned to each machine. The mapping heuristics can be grouped into two categories: on-line mode and batch-mode heuristics. In the on-line mode, a task is mapped onto a machine as soon as it arrives at the mapper . In the batch mode, tasks are not mapped onto the machines as they arrive; instead they are collected into a set that is examined for mapping at prescheduled times called mapping events.

3. What are the types of Dynamic heuristics algorithm?
  • On-line mode heuristics
  • Batch mode heuristics

4.Give grid scheduling algorithms and strategies
  • First-Come-First-Served (FCFS) policy.
  • Backfilling policy.



5. The advantages of Condor-G?
·         It allows the user to treat the grid as an entirely local resource, with an API and command line tools that allow the user to submit jobs, to query a job’s status, to be informed of job terminations or problems and to obtain access to detailed logs.
·         Condor-G is built to tolerate four types of failure: crash of the Globus  JobManager, crash of the machine that manages the remote resource, crash of the machine on which the GridManager is executing, and failures in the network connecting the two machines.
·         A user-supplied list of GRAM servers or a personal resource broker are used to achieve the resource discovery and scheduling. The information from resources is gathered and then the Matchmaker is used to make brokering decisions.
·         Credential management. Condor-G deals with credential expiration by periodically analyzing the credentials for all users with currently queued jobs. Credentials may have been forwarded to a remote location, in which case the remote credentials need to be refreshed as well.

6. What are the grid scheduling scenarios?
  • Enterprise Grids
  • High Performance Computing Grids
  • Global Grids

7.List some of the metascheduling schemes
  • Centralized Scheme
  • Hierarchical Scheme
  • Distributed Scheme

8. Give some service directories supported by grid services
  • MDS
  • UDDI
  • ICENI

9.Describe  Semantic service  and Syntactic service discovery
Semantic service discovery takes into account the semantic meaning of aparameter in addition to syntactic matching. The interface description is transformed into an ontology which is a knowledge schema especially for services. Semantic information of services consists of their extensive descriptions including, but not limited to, capabilities, functionality, portability and system requirements
Syntactic service discovery mainly focuses on the abstract part of a WSDL description: operation and input/output messages. Service discovery is performed by querying the name or the type of a service. The service is advertised by its service information (i.e. name, type) in the registry. By retrieving this service information, the user can discover services.



10. List the information provider of MDS4.
Hawkeye Information Provider: An Information Provider that gathers Hawkeye data about Condor pool resources using the XML mapping of the GLUE schema and reports it to a WS GRAM service, which publishes it as resource properties.
  • Ganglia Information Provider: An Information Provider that gathers cluster data from resources running Ganglia using the XML mapping of the GLUE schema and reports it to a WS GRAM service, which publishes it as resource properties.
  • WS GRAM: The job submission service component of GT4. ThisWSRF service publishes information about the local scheduler.
  • Reliable File Transfer Service (RFT): The file transfer service component of GT4.
  • Community Authorization Service (CAS): This WSRF service publishes information identifying the virtual organization (VO) that it serves.
  • Any other WSRF service that publishes resource properties.

11. What is Data-intensive service scheduling
Data-intensive applications executing over a computational grid demand large data transfers which are normally costly operations. Therefore, taking them into account is mandatory to achieve efficient scheduling of data intensive applications on grids.

12.What is external,local and dataset scheduler
External Scheduler (ES): Users submit jobs to the External Scheduler they are associated with.
Local Scheduler (LS): Once a job is assigned to run at a particular site (and sent to an incoming job queue) it is then managed by the Local Scheduler.
Dataset Scheduler (DS): The DS at each site keeps track of the popularity of each dataset locally available. It then replicates popular datasets to remote sites depending on some algorithm.

13.Defines principles of  data grid architecture.
  • Mechanism neutrality. The data grid architecture is designed to be as independent as possible of the low-level mechanisms used to store data, store metadata, transfer data, and so forth.
  • Policy neutrality. Within the data grid architecture, data movement and replica cataloging are provided as basic operations, but replication policies are implemented via higher-level procedures. Although default policies are provided, users can easily substitute these policies with application-specific code.
  • Compatibility with grid infrastructure. The data grid tools should be compatible with lower-level grid mechanisms. This approach also simplifies the implementation of strategies that integrate, for example, storage and computation.
  • Uniformity of information infrastructure. This means that we use the same data model and interface to access the data grid’s metadata, replica, and instance catalogs as are used in the underlying grid information infrastructure.

14.Types of fault-tolerant algorithms
Robust algorithm: Robust algorithms are designed to guarantee the correct behavior of the processes which function correctly in spite of faults occurring in other processes during their execution. These algorithms are based on strategies such as the vote or the replication, which maintains the correct behavior of a failure process by other backup processes.
These algorithms will never be blocked by the failure of processes, because of the strategies of the vote and the replication. Usually, a robust algorithm is used to deal with permanent faults.
Stabilizing algorithms: Stabilizing algorithms permit the failure of correct processes. Correct processes might be affected by failure, but the algorithm will eventually repair the failure after certain times. The system with these algorithms can be started in any state (possibly faulty), and stabilizing algorithms should finally resume the correct behavior.

15.Define Replication processes:
The replication is a technique achieving fault tolerance in a distributed system. The replication is considered an effective means to increase the reliability of a distributed system. Moreover, the replication can improve the performance of the system by using the backup servers

PART- B
1.Explain Scheduling algorithms and strategies.
2.Explain service discovery services.
3,Eloborate resource information.
4.Explain Data-intensive service scheduling.
5.Explain fault tolerance techniques.
6.Explain meta schedulers.
7.Explain meta scheduling and grig scheduling schemes.


UNIT-5 GLOBUS GT3 TOOL KIT

1. What are the two aspects involved in GRAM?
·         Job submission
·         Resource Management

2. What are the services provided by GT3?
·         Transient services
·         Persistent services

3. What are the Expression evaluators supported in GT3?
·         Service Data Name Evaluator
·         Service Data Name Set Evaluator
·         Service Data Name Delete Evaluator
·         Service Data XPath Evaluator




4. What is the significance of Message Handler in GT3?
Message Handler provide additional message- handling facilities to the Web/grid service end points as extentions to the basic service implementation logic.These handlers can manage encryption and decryption,loging and auditing.

5. What are the functionalities of Grid Service Wrapper?
·         Pluggable service-specific message handlers to procees messages prior to dispatching to the service instance
·         Mechanism to specify portTypes similar to OperationProviders in GT3
·         Pluggable implementation for system-defined portTypes
·         Built-in support of extended standard-based SOAP headers using WSE

6. Write short notes on Virtual Host Redirect Handler.
It is the core component responsible for redirecting all of the calls to the UHE. These calls include creation of the job and invoking job operations on the created job service.
7. What is GRIM?
Grid Resource Identity Mapper(GRIM) service is executing in the UHE to create a user host certificate.The user host certificate is utilized for mutual authentication between the MJS service and the client.

8. What are the sections in configuration file?
·         Installed providers
·         Executed providers
·         Aggregated subscriptions

9. What are the functions of the index service configuration file?
·         Specifies the service data provider to be enabled for each of the services referencing this configuration file.
·         Specifies which of the enabled providers are to be executed at startup and/or when the configuration file is read.It contains the necessary parameters relevant to the provider’s execution.
·         Specifies notification and subscription of service data to other service instances,which allows for aggregation of service data from multiple services

10. What is the use of File Stream factory Service?
These are helpful services to manage the data needed for the job execution.The factory service creates two file stream services: stdout and stderr.Each of these services has two service results:the URL for the stream destinations and a flag to indicate the activity.

11. What is the function of RFT?
The reliable file transfer service(RFT) is an OGSA-based service that provides interfaces for controlling vand monitoring third-party file transfers using the GridFTP servers.The client controlling the transfer is hosted inside of a grid service so that it can then be managed using the soft state model,and queried using the service data interfaces available to all grid services.



12. What is the role of GridFTP?
GridFTP is a atandard extension to the normal FTP that works with the Grid Computing data requirements.This is a high=performance,secure,reliable,dat transfer protocol that is optimized for high bandwidth across wide area networks.This is a standard that provides GSI security,parallel transfer capabilities and channel reusability.

13. What is the function of PLS?
The replica location service (RLS) maintains and provides access to mapping information from logical names regarding data items to target names.These target names may represent physical locations of data items or an entry in the RLS may map to another level of logical naming for the data item.

14. List out the features of grid service container
·         Light weight service introspection and discovery
·         Dynamic deployment and soft state management of state ful grid services
·         Transport-independent, message level security infrastructure, message singing,
             Encryption

15. Define DII(Dynamic Invocation Interface)
This software pattern eliminates the need for clients to know in advance a service’s exact name, operations, and parameters, a DII client can discover this information at runtime using a service broker that can look up the service description(WSDL).

16. What are the requirements of GT3 information services?
·         A basis for configuration and adaptation in heterogeneous environments
·         Uniform and flexible access to static and dynamic information
·         Scalable and efficient access to data
·         Access to multiple information sources

17. What are the most common Gt3 handlers?
·         Authentication service Hanlder
·         WS Security Handler
·         Authorization Handler
·         X509 Sing Handler
·         GSS Handler

18. What are the important components in index services
·         Service data providers
·         Data aggregators
·         Grid service registries

19. What is RIPS?
The Resource information provider service is a part of the GRAM.This service utilizes service data providers to execute system level information gathering scripts and tools. When used in conjunction with GRAM it’s purpose is to monitor forked process.


20. What is RFT?
The reliable file transfer service(RFT) is an OGSA based service that provides interfaces for controlling and monitoring third party file transfers using the GridFTP servers. The client controlling the transfer is hosted inside of a grid service.

PART -B
1. Explain the Architecture of globus GT3 toolkit with a neat diagram.(16)
2. Describe about the information management services available in GT3(16)
3. Describe about the index services available in GT3.(16)
4. What are the resource management services offered by GT3 ?(16)
5. Write notes on data management services.(16)
6. Explain briefly about service programming model.(16)