IAB-Feb 04

1

TAPASProgress Report

(Trusted and QoS-Aware Provision of Application Services)

Santosh Shrivastava

Newcastle University

IAB-Feb 04

2March 04 Deliverables

• D3: Service composition and analysis (report)– UCL: done (Sept 03 was the deadline)

– To be discussed today

• D8: Container for group communication– Really about QoS enabled group communication (Camb, Ncl)

– Software deliverable (open source)

• D9: Container for trusted coordination– Really about regulating interactions between organisations (Ncl)

– Software deliverable (open source)

• D10: Container for QoS monitoring– Really about SLA monitoring (Bologna, Ncl)

– Software deliverable (open source)

IAB-Feb 04

3March 04 Deliverables (contd.)

• D13: Second year evaluation and assessment report– Work towards auction system hosting

– Adesso

• Some management related reports..

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4TAPAS Architecture

• ASP should be capable of hosting Virtual Enterprises (VEs)– Distributed applications involving cross organisation interactions

• A key problem in VE management is how enterprises can regulate access to their resources by other enterprises– Enterprises within a VE will therefore require their interactions with

one another other to be strictly controlled and policed.

– there will be a clear need among all parties to embark upon their business relationships underpinned by guarded trust management procedures.

– Need explicit ways of representing contracts and SLAs and ensuring that organisational interactions follow what is stated in a contract and the services meet the QoS properties stated in SLAs

IAB-Feb 04

5TAPAS Architecture

COMPONENT MIDDLEWARE

QoS Management, Monitoring and Adaptation

QoS EnabledApplication Server

Inter-Org.InteractionRegulation

QoS Monitoring andViolation Detection

APPLICATIONS

TAPAS Architecture: shaded entities make all the difference

IAB-Feb 04

6TAPAS Architecture

• QoS Enabled Application Server– The QoS management, monitoring and adaptation layer is intended to

make the underlying application server QoS enabled.

– two principal middleware services, named Configuration Service and Controller Service

– QoS requirements of hosted applications as stated in SLAs will be specified using SLAng

– SLAng specification will be used for initialising various QoS related configuration information required by the configuration service of the application server, through the deployment descriptors

– To be discussed later today (Bologna)

IAB-Feb 04

7TAPAS Architecture

• D8: QoS enabled group communication– Developed a novel, adaptive multicast protocol

IAB-Feb 04

8TAPAS Architecture

• D9: trusted coordination– Inter-Organisation Interaction regulation subsystem – Trust achieved through regulation

» We assume that interacting entities cannot simply rely on the trust they have in one another.

» To be of practical use, such trust relationships must be managed and observed

» Because of this, interacting parties must resort to mechanisms that guarantee the rights and obligations that each interacting entity promises to honour.

» In the worst case, violations of agreed interactions are detected and notified to all interested parties• an audit trail of all interactions will need to be maintained

– Two level mechanism:» Contract management (rights and obligations) using FSMs +

RBAC» Infrastructure support for non-repudiable interactions

• Implementing novel mechanisms in J2EE server (Jboss).

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9TAPAS Architecture

• D10: QoS monitoring– QoS Monitoring and Violation Detection subsystem

» Several of the rights and obligations in SLAs in a contract refer to the quality of service (e.g., service availability, performance guarantees).

» interacting entities cannot simply rely on the trust they have in one another and assume that QoS levels are being honoured.

» a service provider must be able to demonstrate that the offered service meets the QoS levels promised to service users

» hosted applications and services need to be instrumented with appropriate sensors for measuring QoS parameters

» The parties involved must also agree on the QoS evaluation techniques (calculation procedures to be used)

IAB-Feb 04

10TAPAS Architecture

» These details need to be encoded in some way in the SLAng specification language.

» SLAng specification can be used for configuring the monitoring and violation detection service.

– Monitoring and Violation Detection subsystem could be a third party service

– Architecture to be discussed later today

IAB-Feb 04

11TAPAS Architecture

• Working on auction application– To be discussed today