2012 3 overview of cloud computing 1

Cloud ComputingAn Introduction

Course Material 2011

Chapter 3

Ravindra Dastikop ravindra.dastikop@gmail.com

Cloud Complete

Agenda

● Basics ○ Cloud computing – meaning, various

definitions and perspectives, examples○ Evolution of Cloud computing ○ Essential features and properties of cloud

computing● Service and deployment models

○ Service models- what to expect from cloud vendors ?

○ Deployment models – how to use cloud for business ?

What is Cloud Computing?

Different Views

Cloud Computing: Simplified Cloud computing is a model of delivering computing

resources from the Internet to the user.

Cloud service - An example

when you get connected to service like Gmail, Hotmail etc - you are really connecting to a massive pools of servers somewhere out there on the internet

Source: http://howtogeek.com

Computing Resourcesavailable as cloud service

Software- Applications, OS, service

Hardware ( processors, servers, memory, cards)information - encyclopedia, search engine

computer connected to the netmobile user

Connected TV

Paradigm ● Direct to U From the “ net” as

against “on premise” ( DTH)● Direct to user – TV channel subscription● Use without owning- Ramco OnDemand

Cloud ● Rental basis- Google for Enterprises ● Procure as u grow (Gmail start with 7GB

and ask for more ) ● From NIL to FULL

Direct Home

Cloud Computing Vs Traditional Computing

YOURDATA

YOUR BUSINESS

CONTROLAPPLICATION

DOCUMENT

Computing before cloud

Computer: ownSoftware: Installeddata: stored on u r machine

YOURDATA

YOUR BUSINESS

CONTROL SPREAD SHEETS

STORAGE

YOURDATA ?

HOSTED SERVICES

The Internet

GOOGLE DOCS

PROCESSING

Cloud Computing Services

● Application: accessed from the web (Word Processor)

● Document : Stored on the web

Office 365

Cloud from User Perspective

User perspective

Why is it called Cloud Computing

Why is it called Cloud Computing ?Example

Because in network diagrams, the Internet is depicted as a cloud.......

Source: http://howtogeek.com

● The name cloud computing was inspired by the cloud symbol that’s often used to represent the Internet in flow charts and diagrams. Cloud computing is a general term for anything that involves delivering hosted service over the Internet.

Origin● “Comes from the early days of the Internet where we

drew the network as a cloud… we didn’t care where the messages went… the cloud hid it from us”

– Kevin Marks, Google

● First cloud around networking (TCP/IP abstraction)● Second cloud around documents (WWW data

abstraction)● The emerging cloud abstracts infrastructure

complexities of servers, applications, data, and heterogeneous platforms

Cloud: origin : Telephone Networks

Cloud symbol to represent networks

Why is it called cloud ?

Cloud Computing

Definitions

Wikipedia

● Cloud computing is Internet-based computing whereby shared resources, software and information are provided to computers and other devices on demand, like electricity grid.

● Cloud computing is a style of computing in

which dynamically scalable and often virtualized resources are provided as a service over the Internet

Virtualization Virtualization is abstracting the hardware to run virtual instances of multiple guest operating systems on a single host operating system.

Wikipedia- explanation

● “Cloud Computing is a computing paradigm shift where computing is moved away from personal computers or an individual application server to a “cloud” of computers.

● Users of the Cloud only need to be concerned

with the computing service being asked for, as the underlying details of how it is achieved are hidden.

Wikipedia- explanation

●This method of distributed computing is done through pooling all computer resources together and being managed by software rather than a human

●Cloud computing is a model of computing wherein an end user sources all computing resources directly from the internet without installing or owning them.

Virtualization - Forms

Virtualization

Definition from NIST ● Cloud computing is model for enabling

convenient, ○ on-demand network access to a

shared pool configurable computing resources ( e.g. networks,■ servers, ■ storage, ■ applications,

○ and services) ○ that can rapidly provisioned and

released with minimal management or service provider interaction.

Berkley

● Cloud computing refers to both the applications delivered as services over the Internet and the hardware and system software in the data centers that provide those services

● The services themselves have long been referred to as Software as a Service ( SaaS), so we use the term. “ The data center hardware and software is what we will call a cloud

● When a cloud is made available in a pay-as-you use-go to the public- the service being sold as Utility computing

● A cloud is a type of parallel and distributed systems consisting of a collection of interconnected and virtualized computers that are dynamically provisioned and presented as one or more unified computing resource based on service-level agreements established through negotiations between the service provider and consumer.

Gartner

● Gartner defines cloud computing as " a style of computing where massively scalable IT-enabled capabilities are delivered as a service to external customers using Internet technologies.

● Cloud Computing is simply a platform where individuals and companies use the Internet to access endless hardware, software and data resources for most of their computing needs, leaving the mess to their Cloud Service Providers

Layman’s definition

● Cloud computing may be defined as computing paradigm that supplies computing as "utility".

● The utilities can be purchased in quantities of choice, in location of user preferences.

● This may be on pay per use or pay per time.

why so many definitions ?

Summary of Cloud computing Definitions

● Cloud computing is a paradigm of computing, a new way of thinking about IT and ITeS industry

● Central concepts○ Utility computing○ SOA- service oriented architecture○ SLA- service level agreement

● Properties and characteristics○ High scalability and elasticity○ High availability and reliability○ High manageability and interoperability○ High accessibility and portability○ High performance and optimization

● Enabling techniques ○ Hardware virtualization○ Paralleled and distributed computing○ Web services

Stop One

Any questions?

Evolution of Cloud Computing

where did we start and how did we arrive here?

EvolutionMainframe

● First phase -

Evolution Personal Computing

● Second phase

Stages in ComputingClient-server computing

● Third phase -

Stages in ComputingClient server–web application ● Fourth phase -

Stages in ComputingGrid Computing

● Fifth phase -

Computers come under different administrative domains

Stages in Computing Cloud Computing

● Sixth phase -

Stop Two

The Anatomy of Cloud Computing

characteristics, models

The Anatomy of Cloud Computing

The cloud model promotes availability and composed of ●Five essential characteristics ●Three service models and ●Four deployment models.

The Properties of Cloud

● On-demand self-service● Broad network access, definition, meaning

● Resource pooling, explanation example

● Rapid elasticity, meaning

● Measured Service

Cloud Computing: features ● On-demand service-

○ you can get what u need and when u need● Broad network access-

○ Cloud computing brings network-based access to, management of , software and services – meaning access anywhere and anytime

● Resource pooling – ○ A large pool of users shares location-independent

resources and costs in an environmentally sustainable manner

● Flexible resource allocation○ Cloud computing service can scale up and down rapidly

as demands fluctuate ● Measured service

○ Most cloud usage is metered often per user/hour. U pay for what u consume

Computing Models

Deployment Models

Ways in which Cloud be used

Public cloud

● A public cloud is cloud implementation shared by the general public with a wide range of services available.

● It is owned and managed by an enterprise that sells/offers freely cloud services on pay-per-use ○ example 1○ example 2

Private cloud

● A private cloud implementation restricts access to internal users such as employees. It stays within a firewall

Hybrid cloud

● A hybrid cloud is an approach that uses a public cloud for some services such as class room applications- lesson plan

● But uses a private cloud other uses such as storage of sensitive data – examination data that must be accessed by few concerned or compliance data

Hybrid Cloud

Cloud Computing- MODES- another example

Private cloudPublic CloudHybrid cloud

Government Cloud

Indian Government Approach to Cloud Computing

Four deployment Models

Clouds can take the following avatars

Four deployment models

● Private cloud, ● Community cloud,

● Public cloud,● Hybrid cloud

Types by visibility:

Google

Stop Three

send u r questions

The Three Service Models

The three service models

● Cloud Software as a Service (SaaS),● Cloud Platform as a Service (PaaS), ● Cloud Infrastructure as a Service (IaaS)

Service Models- An Analogy

Suppose u have moved to new town and want to find a

accommodation for yourself?

What are u options ?

What is u r choice ?

Build a new House ?

Buy an empty house ?

Live in a hotel

Build a New house ( IaaS)

Difficult, time consuming

Infrastructure as a Service (IaaS)

● Vendor provides ○ VM, ○ Storage and ○ Computations

● Target:

○ Developers and ISV ● Examples

○ Amazon ○ Smugmug- a paid digital photo sharing service

http://dastikop.blogspot.com

Infrastructure as a Service● Infrastructure as a service ( IaaS)

○ The capability provided to the consumer is to provision processing, storage, networks, and other basic computing resources.

○ User can deploy and run arbitary software that could include OS and applications

○ The consumer does not manage or control underlying cloud infrastructure but has control over operating systems, storage, deployed applications, and certain limited control over select networking components

● Examples○ Tata Communication○ Red hat○ Amazon○ Eucalyptus

Renting/buy a House (PaaS)

Rent or buy a house

Furnishing is u r freedom

Platform as a Service (PaaS)

● Vendor provides higher level API○ hides machines, storage etc

● Target: Developers and SME

● Vendors:

○ Force.com, ○ Google AppEngine

Stay in a Hotel (SaaS)

Software as a Service ( SaaS)

Business software delivered through cloud

Target: SME & Enterprise

Vendors: Google, Microsoft, Salesforce

MS word, Docs, spreadsheets, CRM

Cloud computing service models

Picture source

Service models overview● What if u want to have an IT department

○ Similar to build a new house in our analogy■ U can rent some virtualized infrastructure and build up u r

own IT system using these resources, which is under your full control

■ Technically speaking u r using Infrastructure as a service( IaaS) solution

○ Similar to buy an empty house in our analogy■ U can directly develop u r IT system through one cloud

platform and do not worry about lower level resource management

■ Technically speaking, u r using Platform as a service ( PaaS) Solution

○ Similar to live in a hotel in our analogy ■ U can use directly use some existing IT system solution,

which are provided by some cloud application service providers, without knowing any technical details about how these services are operated

■ Technically speaking , u r using software as a service ( Saas) solution

End of Cloud Computing Fundamentals

Enabling Technologies

Cloud computing is made possible and powered by the following technologies. Key enabling technologies include: ● Fast wide-area networks, ● powerful, inexpensive server computers, ● high-performance virtualization for

commodity hardware● Multi-tenancy .

Cloud Computing

Operational concepts

Central ideas● User perspectives

○ User don't care about how the works are done■ Instead, they only concern about what they can get

○ User does not care about what the provider actually did■ Instead, they only concerned about their quality of

service○ Users do not want to own the physical infrastructure

■ Instead they only want to pay for what they use

● What does user really care?

Utility computing

● One service provision modeling ● Service provider makes computing resources and

infrastructure management available to the customer as needed, and charges them for specific usage rather than a flat rate (tata)red hat

● Like other types of on-demand computing, the utility model seeks to maximize the efficient use of resources and / or minimize associated costs

Service/ SOA

The fundamental concept of Cloud Model

What is a service ?

● Service is what you connect together using web services

● Service is the end point of a connection● Functionalities of service

○ A service should be well-defined ( input, output)

○ A service should be self-contained○ A service should not depend on the context or

state of other services○ Add picture of service

What is a web service ?

● Definition○ Web service is a self-describing and stateless modules that

perform discrete units of work and are available over the network○ Web service providers offer APIs that enable developers to exploit

functionality over the Internet, rather than delivering full-blown applications

● WSDL ○ Expressed in XML which include both data type and message○ Four types of operations

■ One way- messages sent without a reply required■ Request and response – sending and receiving message■ Solicit response – a request for a response■ Notification : message sent to multiple receivers

A web service

Web Service

source: http://jan.newmarch.name/webservices/thailand.html

Service oriented architecture (SOA)

● Definition:○ Service oriented architecture (SOA) is essentially a

collection of services which communicate with each other○ Contain a flexible set of design principles used during the

phases of systems development and integration○ Provide a loosely-integrated suite that can be used within

multiple business domains● Approach:

○ Usually implemented by web service model

Service Oriented architecture

source: alignedstrategy.com

Source: enterprise web

Quality of service

● Original definition○ Quality of service ( QoS) is a set of

technologies for managing network traffic in a cost effective manner to enhance user experience for home and enterprise environments

● Now Qos has becomes to a broad term that is used following areas.

○ Customer care evaluations○ Technological evaluations

Quality of service

● Customer care evaluations○ OoS is usually measured in terms of issues that have

a direct impact of the customers○ Only issues that produce a negative effect on the

goods and services received by the customer come under scrutiny

● Technological evaluations○ QoS has to do with the efficient operation of various

systems○ This can lead to adjusting procedures or adapting

software programs and code to achieve the desired effect with making a more efficient use of available resources

Source: http://www.bgp-qos.org/forum/styles/prosilver/imageset/bgp-qos.jpg

Service Level Agreements

● Definition:○ A service-level agreement (SLA) is a contract between a

network service provider and a customer that species, usually in measurable terms ( QoS), what services the network service provider will furnish

● Common content in contract○ Performance guarantee metrics

■ Up-time and down-time ratio■ System throughput■ Response time

○ Problem management details○ Penalties for non-performance○ Document security capabilities○ Example ○ SLA Google example

cloudave.com

Stop Two

Any Questions

Revision

● Different views of cloud computing ○ wikipedia,○ Berkely etc

● Concepts○ service, web services, SLA, QoS Virtualization

● Properties of Cloud● Service Models

○ IaaS, PaaS and SaaS ● Deployment models

○ private, public○ community, hybrid

Class No 02

19.02.2011

Scalability and Elasticity

● World without limitations ●

Scalability & Elasticity

● What is scalability?○ A desirable property of a system, a network, or a process,

which indicates its ability to either handle growing amount of work in a graceful manner or to be readily enlarged

● What is elasticity?○ The ability to apply a quantifiable methodology that

allows for the basis of an adaptive introspection with in a real time infrastructure

● But how to achieve these properties ?○ Dynamic provisioning○ Multi-tenant design

Dynamic provisioning

● is a simplified way to explain a complex networked server computing environment where server computing instances are provisioned or

● deployed from any administrative console or client application by the server administrator ; or by any other enabled user.

Dynamic provisioning (console)

Dynamic Business demands

Dynamic Provisioning

hds.com

○ The traditional computing model suffers from twin problems of underestimates/overestimates

■ Underestimate the system requirement/utilization which results in under provision. This may lead to loss of users and loss of revenues

The challenge of underestimate

Dynamic Provisioning

○ The traditional computing model suffers from twin problems of underestimates/overestimates

■ Overestimate system requirements/utilization results in low or sub-optimal utilization. This leads to unused or wasted resources

The problem of Overestimate

Under-utilizationwaste of resources

○ Dynamic Provision is the solution: Cloud computing provides dynamic provisioning in which cloud computing resources are provisioned dynamically

■ Meet seasonal demand variations■ Meet demand variation between different industries ( ice

cream/refrigerators) ■ Meet burst demand for some extraordinary events (

thehalka/wikileaks/ticketing systems / animato.com

Multi-tenant

● Multi-tenant refers to a principle in software architecture where a single instance of software runs on a server; serving multiple client organization

● With a multi-tenant architecture, a software application is designed to virtually partition its data and configuration thus each client organization works with customized virtual application instance example: Cloud applications – Gmail

multi-tenant

Multi-tenancy

Availability and Reliability

○ Availability is the degree to which a system, subsystem, or equipment is in a specified operable and committable state at the start of the mission, when a mission is called for at an unknown time

■ examples ○ Cloud systems usually require high availability i.e. 24/7 and 365

days. 99.999 uptime, can be down for 5 minutes in an entire year○ The reliability is the ability of a system or component to perform

its required functions under stated conditions for a specified period of time

○ Availability and Reliability are achieved by means of■ Fault-tolerant systems■ Require system resilience■ Reliable system security

availability

Reliability

Fault-tolerance

○ Fault-tolerance is the property of the system that enable system to continue operating properly in the event of the failure of some of its components

○ If its operating quality decreases at all , the decrease is proportional to the severity of the failure , as compared to naively-designed system in which even a small failure can cause total breakdown

○ Characteristics of Fault tolerant systems■ No single point of failure■ Fault detection and isolation to the failing component■ Fault containment to prevent propagation of the failure■ Availability of reversion modes

Fault tolerant

○ Single point of Failure ( SPOF)■ A part of a system which, if it fails will stop the entire

system from working■ The assessment of a potentially single location of failure

identifies the critical component of a complex system that would provoke a total system failure in case of malfunction

■ Prevention of SPOF■ If system experiences a failure, it must continue to

operate without interruption during the repair process

Fault-tolerant

Fault tolerant

■ Fault detection and isolation ( FDI) to the failing component

■ A subfield of control engineering which concerns itself with monitoring a system, identifying when a fault has occurred and pinpoint the type of fault and its location

■ Isolate failing component ■ When a failure occurs, the system must be

able to isolate the failure to the offending component

Fault tolerance

■ Fault containment to prevent propagation of the failure

■ Some failure mechanism can cause a system to fail by propagating the failure to the rest of the system

■ Mechanism that isolate a rogue transmitter or failing component to protect the system are required

■ Availability of reversion modes■ System should be able to maintain some

check points which can be used in managing the state changes

System Resilience

○ Resilience is the ability of the system to provide and maintain an acceptable level of service in the face of faults and challenges to normal operations

○ Resiliency pertains to the system’s ability to return to its original state after encountering trouble. In other words, if a risk event knocks a system offline, a highly resilient system will return back to work and function as planned as soon as possible

○ Some risk events■ If power is lost at a plant for two days, can our system

recover ?■ If a key service is lost because a database becomes

corrupt, can the business recover ?

Resilience

System Resilience

● Disaster Recovery○ Disaster recovery is the process, policies and procedures

related to preparing for recovery or continuation of technology infrastructure critical to an organization after a natural or human-induced disaster

● Some common strategies○ Backup

■ Make data off-site at regular interval■ Replicate data to an off-site location ■ Replicate whole system

○ Preparing ■ Local mirror systems■ Surge protector■ UPS

System security

System Security

● Security issue in cloud computing○ Cloud security is an evolving sub-domain of computer

security, network security and , more broadly, information security

○ It refers to a broad set of policies, technologies, and controls deployed to protect data, applications, and the associated infrastructure of cloud computing

System Security

● Important security and privacy issues:● Data protection

○ To be considered protected, data from one customer must be properly segregated from that of the other

● Identity management○ Every enterprise will have its own identity management

system to control access to information and computing resources

● Application security○ Cloud providers should ensure that applications available

as a service via the cloud are secure● Privacy

○ Providers ensure that all critical data are masked and that only authorized users have access to data in its entirely

Manageability & Interoperability

● I want full control

Manageability and interoperability

● What is manageability ?● Enterprise-wide administration of cloud computing

systems. Systems manageability is strongly affected by network management initiatives in telecommunications

● What is interoperability?○ Interoperability is a property of a product or system, whose

interfaces are completely understood, to work with other products or systems, present or future , without any restricted access or implementations

● But how to achieve above two ?○ System control automation○ System state monitoring

Control automation

● Four functional areas:● Self-configuration

○ Automatic configuration of components ● Self-healing

○ Automatic discovery, and correction of faults● Self-optimization

○ Automatic monitoring and control of resources to ensure the optimal functioning with respect to defined requirements

● Self-protection○ Proactive identification and protection from arbitrary

attacks

Control automation

● What is autonomic computing ?○ Its ultimate aim is to develop computer system capable

of self-management, to overcome the rapidly growing complexity of computing systems management, and to reduce the barrier that complexity poses to further growth

● Architectural framework○ Composed of autonomic components (AC) which will

interact with each other○ An AC can be modeled in terms of two main control

loops ( local and global) with sensors ( for self-monitoring), effectors ( for self-adjustment) , knowledge and planer/adapter for exploiting policies based on self-and environmental awareness

System Monitoring

● What is system monitor?○ A system monitor in system engineering is a process

within a distributed system for collecting and storing state data

● What should be monitored in the Cloud?○ Physical and virtual hardware state○ Resource performance metrics○ Network access patterns○ System logs

● Anything more ?

Monitoring Systems

Billing system

● Billing System in Cloud○ User pay for as many as they used (Tata)○ Cloud provider must first determine the list of service

usage price○ Cloud provider have to record the resource or service

usage of each user, and then charge user by these records

● How can cloud provider know user’s usage?○ Get those information by means of monitoring systems○ Automatically calculate the total amount of money to be

paid by the user. And automatically request money from user;s bank account

Billing Systems

Performance & Optimization

● High performance Improvement

Performance & Optimization

● Performance guarantees ??○ As the great computing power in cloud, application

performance should be guaranteed○ Cloud provider make use of powerful infrastructure or

other underlining resources to build up a highly performed and highly optimized environment, and then deliver the complete services to cloud users

● But how to achieve this property?○ Parallel computing○ Load balancing ○ Job scheduling

Parallel Processing

● Parallel processing○ Parallel processing is a form of computation in

which many calculations are carried out simultaneously on the principle that large problems can often be divided into smaller ones, which are then solved currently

● Parallelism in different levels○ Bit level parallelism○ Instruction level parallelism○ Data level parallelism○ Task level parallelism

Parallel Processing

● Hardware approaches○ Multi-core computer○ Symmetric multi-processor○ General purpose graphic processing unit○ Vector processor○ Distributed computing

■ Cluster computing■ Grid computing

● Software approaches○ Parallel programming language○ Automatic parallelism

Job scheduling

● What is a job scheduler?○ A job scheduler is a software application that is in

charge of unattended background executions, commonly known for historical reasons as batch processing ( daemon)

● What should be scheduled in cloud?○ Computation intensive tasks○ Dynamically growing and shrinking tasks○ Tasks with complex processing dependency

● How to approach this ?○ Use pre-defined workflow○ System automatic configuration

Load balancing

● What is load balancing?○ Process

■ Load balancing is a technique to distribute workload evenly across two or more computers, networks links, CPUs, hard drives, or other resources,

○ Objectives:○ in order to get optimal resource utilization,○ maximize throughput, minimize response time, and

avoid overload● Why should be load balanced?

○ Improve resource utilization○ Improve system performance ○ Improve energy efficiency

Challenge of Load Balancing

Accessibility & Portability ● Anyone, Anytime,Anywhere●

Accessibility & Portability

● What is accessibility ( google accessible )○ Accessibility is a general term used to describe the

degree to which a product, service, or environment is accessible by as many people as possible

● What is service portability?○ Service portability is the ability to access services using

any device, anywhere, continuously with mobility support and dynamic adaptation to resource variations

● But how achieve these objectives?○ Uniform access○ Thin client

Device portability example

Uniform Access

● How do users access cloud services?○ cloud providers should provide their cloud service by

means of widespread accessing media. In other words, users from different operating systems or other accessing platforms should be able to directly be served

○ Nowadays , web browser technique is one of the most widespread platform in almost any intelligent electronic devices. Cloud-services take this into consideration, and delivery their services with web-based interface through the Internet

Thin Client

● What is thin client?○ Thin client is a computer or a computer program which

depends heavily on some other computer to fulfill its traditional computational roles. This stands in contrast to the traditional fat client, a computer designed to take on these roles by itself

● Characteristics○ Cheap client hardware

■ While the cloud providers handle several clients sessions at once , the clients can be made out of much cheaper hardware

Thin Clients

○ Diversity of end devices■ End user can access cloud service via plenty of

various electronic devices which include mobile phones and smart phones

○ Client simplicity■ Client local systems do not need complete

operational functionalities

Questions?

send u r questions

Ravindra Dastikop

Cloud Research

Kamesh Pemmaraju heads cloud research at Sand Hill Group and he helps companies—enterprises and technology vendors—accelerate their transition to the cloud. His blog has been recognized in the top 50 bloggers on cloud computing and also in CloudTP's best cloud computing blogs list. He welcomes your comments, opinions, and questions. Drop in a line to kamesh@sandhill.com. For updates on news, views, interviews, webcasts, events, and blog posts, follow me on twitter @kpemmaraju.

Cloud Computing: features ● On-demand service-

○ you can get what u need and when u need● Broad network access-

○ Cloud computing brings network-based access to, management of , software and services – meaning access anywhere and anytime

● Resource pooling – ○ A large pool of users shares location-independent

resources and costs in an environmentally sustainable manner

● Flexible resource allocation○ Cloud computing service can scale up and down rapidly

as demands fluctuate ● Measured service

○ Most cloud usage is metered often per user/hour. U pay for what u consume

Using Clouds

Cloud Service Models

Service Models- An Analogy

Suppose u have moved to new town and want to find a

accommodation for yourself?

What are u options ?

What is u r choice ?

Build a new House ?

Buy an empty house ?

Live in a hotel

Build a New house ( IaaS)

Difficult, time consuming

● Target:

○ Developers and ISV ● Examples

○ Amazon ○ Smugmug- a paid digital photo sharing service

Renting/buy a House (PaaS)

Rent or buy a house

Furnishing is u r freedom

● Target: Developers and SME

● Vendors: Force.com, Google AppEngine