Integrated Lifecycle of IT Services in a Cloud Environment

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22 Οκτ 2013 (πριν από 3 χρόνια και 7 μήνες)

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Integrated Lifecycle of IT Services in
a Cloud Environment

Karuna P Joshi

Ebiquity Research Group,

Computer Science and Electrical Engineering Dept, UMBC


http://ebiquity.umbc.edu/; http://mc2.umbc.edu

kjoshi1@umbc.edu

Introduction: Software Delivery Models


In
-
house approach
: Traditionally, software applications
development and maintenance has been done within
the company with it’s own employees.


Outsourced or Off shored approach
: Software
applications purchased by companies. Development
and maintenance is contracted to consulting/staffing
companies who could be based anywhere in the
world.


Services on the Cloud approach
: IT services
purchased from software manufacturers who could
be a single entity or a mix. Also termed virtualized
software to imply the software development and
maintenance is transparent to the consumer.

IT Services


Information Technology (IT) increasingly being
viewed as a “Service” offered to an organization


Software, Customizations, Support, Hosting and
Maintenance purchased as a “Service” from providers.


The X as a Service alphabet soup


Infrastructure as a Service (IaaS)


Platform as a Service (PaaS)


Database as a Service (DaaS)


Software as a Service (SaaS) etc…


Services are virtualized
--

shared across multiple
provisioning.


Virtualized IT Services on the Cloud


Composed of one or more components
developed by one or more providers and
delivered as a single service to the consumer.


Service dynamically composed


Service structure/components not pre
-
determined


Based on consumer’s requirements. (On demand
composition)


Delivered virtually via the Cloud / grid.


Consumer specifies both functional and non
functional requirements like quality, security,
compliance etc.

Key Open Issues


Composition and orchestration of services currently
requires a programmer with knowledge of


WSDL (Web Services Definition Language) or similar

languages to
describe the services.


BPEL (Business Process Execution Language) to specify the
interactions between the services.


Users who are not tech
-
savvy cannot use this.


Currently there is no negotiation capability for service
composition in cloud environment


Cannot define variable constraints or negotiate on cost, SLAs
etc.


No automation of the current approach to discover
services like RFPs, etc.

Our Approach



We propose a policy
-
based approach to automate the
service lifecycle on the Cloud.


Use Semantic web languages/technologies like OWL (Web
Ontology Language), RDF (Resource Description
Framework) and associated reasoning infrastructure such as
AIR, Jess, etc.


Extend the Service Oriented Architecture (SOA) to
factor in expressive policies, negotiation and rules
-
based
reasoning to make it more suitable for Cloud
Environment.

Enterprise Policies




Business Processes



Budgetary rules



HR policies



Infrastructure / Facilities



Security



Compliance etc.

Service Policies



Service Cost



Service Agreements



Service Obligations



Security



Compliance, Taxes etc.

Service

Negotiation



Request for
Service



Constraints


Provider Service
Environment



Service components



Dependent Services



Service Agents



Development platform



Staging platform

Enterprise IT
Service Environment



Services



Packaged applications



User devices (e.g. PCs,
Laptops, PDAs etc.)



Servers



Network Infrastructure

Policy for Services on the Cloud

Policies

Policies

SERVICE CLOUD

Service
Presentation



SaaS



DaaS



PaaS



IaaS

Request

For service

service

service

PROVIDER

CONSUMER

Service Level
Agreement

Methodology for Service Lifecycle


Our proposed methodology divides Service
Lifecycle into Five Phases


Requirements


Discovery


Negotiation


Composition


Consumption


This Methodology is applicable on private or public
cloud.


Have proposed metrics to track success of each
phase.


Have developed initial version of ontologies for the
five phases.

Phases of IT Services Lifecycle

Service
Requirements

Service Discovery

Service Negotiation

Service Composition

Service Consumption

SERVICE CLOUD

CONSUMER

Service delivered

Contract signed

Provider(s) identified

Service specified

New Service needed

Services Requirements phase



Policy Manager



Policy Type


Hard constraints


Soft constraints


Dependents


Parents

Services Manager



Name


Provider


Type


Attributes


Location


Dependencies

consumer

service

Services
Procurer



Service specs


Policies with
constraints



RFS generator

Service Cloud

Provider 1

‘Request for
Service’ Monitor


Service


Requirements

‘Request for
Service’ Monitor


Service


Requirements

Provider 2

policy

‘Request for
Service’ Monitor


Service


Requirements

Provider 4

policy

specs

‘Request for
Service’ Monitor


Service


Requirements

Issue
Request
for
Service
(RFS)

Provider 3

Consumer

Service Requirements


Requirements for a service will include


Functional specifications (tasks to be automated)


Technical specifications


Software applications and constraints


Hardware Policy


Mobile device, PC, Server, Multicore etc.


Operating System Policy


single OS, multiple OS


Language Support Policy


Human Agent specifications


Agent experience


Agent skill level


Geographical location constraints


Nationality/Work permit constraints


Service Requirements (contd…)


Requirements for a service will include


Security Policy


Role


Permissions


Data Quality Policy


Low quality data may be acceptable to consumer if it provides
cost saving


Service Compliance Policy


Standards adhered


Certifications needed


Government regulations adhered.


Example of Requirements Policy

Data Quality policy
-

// allows services of low data quality to be accepted if the service is free of cost.

// Using AIR Policy Language


@forAll

:SERVICE_QUALITY,

:COST.

:data_quality_policy a air:Policy;


rdfs:label "Data Quality policy";


air:rule

:data
-
quality
-
rule.

:data
-
quality
-
rule a air:Belief
-
rule;


rdfs:label "data quality rule";


air:pattern {



:SERVICE_QUALITY quality_level

:LOW.



:COST service_cost

:0.


};


air:assert {:SERVICE_QUALITY air:compliant
-
with

:data_quality_policy.};


air:alt { air:assert {:SERVICE_QUALITY air:NOTcompliant
-
with

:data_quality_policy.}}.


Class : Request for Service


Service Domain


Exp_Svc_Begin_Date


Exp_Svc_End_Date


RFS_Respond_by_dt



Cost_constraint

Class:

Specification



Name


Description

Class:

Security
policy

Class

Technical
Specs

Class :

Functional
Specs


Task


Description

High Level Ontology for Service Requirement Phase

Class:

Hardware
Details

Class:

Operating
System
Details

Class:

Compatible
Application
Details

Class: Domain


Domain


Characteristics

Class: Human
Agent Specs



Experience


Availability


Nationality


Other

Constraints

Class:

Data
Quality
policy

is part of

is part of

is part of

is part of

is part of

Must
include

Class:

Consumer


Consumer
-
ID


Description


is sues

is part of

Is part of

is part of

Is part of

Is part of

is part of

Class:

Service
Compliance

is part of

Service Discovery


Services search/discovery engine


Used to search available services that match the
specifications


Identify functional gaps that exist in services discovered



Service Certification


A central registry, like UDDI, will certify a service provided.


Consumers can refer to this certification when selecting a
service.

Service Discovery phase

Service

Requirements

Service Discovery Engine

List of service providers
with advertised service,
service levels and cost

Service Verification /
Certification

SERVICE CLOUD

CONSUMER

Service

Negotiation

Policy in Service Discovery phase



Policy Manager



Policy Type


Hard
constraints


Soft constraints


Dependents


Parents

Services
Manager



Name


Provider


Type


Attributes


Location


Dependencies

consumer

service

Services
Procurer



Service


Policies


Generate
RFS


RFS
negotiation

Service Cloud

Provider 1

Cannot
provide
service

RFS Responder



Cost



Availability



Functionality



Requirements met

Provider 2

policy

RFS Responder



Cost



Availability

Provider 4

policy

specs

Service
available

Service
available

Provider 3

Service
Provider
Validation


Service


Provider


Validation

Service
Composer



Components



Constraints



Functionality



Requirements met

Functionality,
Requirements met

+

RFS Responder



Availability

Consumer

Class: Service
Certification




Provider


Service Name


Service ranking




Class:

Service Search
Engine

Class : Provider List



Provider


Service details


Service availability


Service Cost

High Level Ontology for Service Discovery Phase

used in

Verifies

Provider

Class : Request for Service


Service Domain


Exp_Svc_Begin_Date


Exp_Svc_End_Date


RFS_Respond_by_dt



Cost_constraint

creates

Class: Consumer



Consumer
-
ID


Description


returns

list to

Class: Provider



Service list


Description

adds to

Service Negotiation


Discussion and agreement that the
Service provider and consumer have
regarding the Service.


Service Level Agreements (SLA) finalized
between consumer and provider


Quality of Service (QoS) decided
between primary provider and
component providers.

Service Negotiation phase

Service

Discovery

Service Quality of Service (QoS)
between primary service
providers and dependent services

Service Level Agreement
(SLA) between consumer
and primary service provider

SERVICE CLOUD

CONSUMER

Service Composition,
Orchestration

Policy in Service Negotiation phase



Policy
Manager



Policy Type


Hard
constraints


Soft constraints


Dependents


Parents

Services
Manager



Name


Provider


Type


Attributes


Location


Dependencies

consume
r

service

Services
Procurer



Service


Policies


Generate
RFS


RFS
negotiation

Service
Cloud

Provider 1

Service
Negotiator



Cost


Availability


Service
functionality


Requirements
met

policy

Service
Negotiator



Cost


Availability


Service
functionality


Requirements
met

Provider 4

policy

specs

Provider 3

Final cost,
SLA,
configuration

Revised soft
constraints,
SLA

Revised cost,
configuration

Iterative
process

Revised soft
constraints,
SLA

Revised cost,
configuration

Iterative
process

Policy
Manager


Policy Type


Hard constraints


Soft constraints


Dependents


Parents

Policy
Manager


Policy Type


Hard constraints


Soft constraints


Dependents


Parents

policy

Consumer

Provider

policy

Class:

Contract

Class:

Service Level
Agreement



SLA Name


Description


SLA Metrics


Penalty

Class:

Contract
Negotiation

Class :

Quality of
Service (QOS)


QOS Name


Description


QOS Metrics


Penalty

High Level Ontology for Service Negotiation Phase

results
in

Class :

Dependent
Service
Sub
-
Contract

Class :

Service
Contract

subClass

of

subClass

of

Class:

Provider
Negotiation

Class:

Consumer
Negotiation

subClass of

subClass of

results
in

is part

of

Class : Provider List


Provider


Service details


Service availability


Service Cost

used in

Class : Request for Service


Service Domain


Exp_Svc_Begin_Date


Exp_Svc_End_Date


RFS_Respond_by_dt



Cost_constraint

used in

Class:

Consumer


Consumer
-
ID


Description


initiates

Class: Provider


Service list


Description

initiates

participates

is part


of

Service Composition Phase


One or more services provided by one or more
providers are combined and delivered as a single
Service.


Service orchestration determines the sequence of
execution of the Service components.


Service
Coupling measure
determines how
dependent main service is on other services or
resources for its delivery


Service
Cohesion

measures

the extent to which
related aspects of a requirement are kept together in
the same service, and unrelated aspects are kept out.

Service Composition phase

Service

Negotiation

Service
composed

Dependant
services

SERVICE CLOUD

CONSUMER

Service

Consumption

Class : OWL
-
S


Composite
Process

High Level Ontology for Service Composition Phase

Is part


of

Defines
metrics
for

Defines
metrics
for

Class: Service
Level Agreement



SLA Name


Description


SLA Metrics


Penalty

Class : Quality of
Service (QOS)


QOS Name


Description


QOS Metrics


Penalty

Class:

Dependent
Service

Class:

Specification



Name


Description

Determines

Class: Provider



Service list


Description

Executes

Service Consumption Phase


Composed Service is consumed and
monitored in this phase.


Key
measures

like Service Performance
and reliability are monitored using
automated tools.


Phase includes Service Delivery, Service
payment.


Customer Satisfaction is tracked in this
phase.

Service Consumption phase

Service

Composition

Service consumed

SERVICE CLOUD

CONSUMER

Service

Requirements

Service Monitored

Service delivered


one time
or periodically as needed

Service
payment

Class : Service
Level Agreement


Task


Description

High Level Ontology for Service Consumption Phase

Class:

Dependent

Components

Class : OWL
-
S


Composite
Process

Class: Provider



Service list


Description

Class:

Consumer


Consumer
-
ID


Description


Class :

Service
Contract

refers to

Part of

is consumed
by

Class: Human
Component

Class :
Tier
1 agent

Class :
Tier
2/ external
agent

Class :

Response

Time

Class:

Assurance

Class:

Reliability

Class:

Presentation

Class :

Performance

Class:

Resolution Time

Class :

Software

components

Class :

Latency

Class :

Throughput

Class:

Security
Policy

Provides

subClass


of

subClass


of

Determine quality for

Service Life cycle: detailed

Identify functional and
technical specifications
Determine domain,
data type and it’s
acceptable quality
levels


“Request for Service”

SERVICE CLOUD

CONSUMER

Service Discovery
Engine

List of service providers with advertised
service, service levels and cost

Service
Certification

Quality of Service (QoS) contracts between
primary service providers and dependent services

Service Level Agreement (SLA) between
consumer and primary service provider

Service composed

Dependant
services

Service packaged,
delivered


one time or
periodically as needed

Service
payment

Service consumed

Service Monitoring

Ongoing Work


Currently developing policies for each phase of
the service lifecycle using policy languages like
AIR policy language developed by MIT.


We continue to refine the IT Service ontology.
Ontology in OWL for the entire Lifecycle is
available at
http://www.cs.umbc.edu/~kjoshi1/IT_Service_Ontology.owl


Developing an integrated quality framework for
virtualized services delivered via the cloud.

Questions ?


Relevant Publications on the Ebiquity
website (http://ebiquity.umbc.edu)