Cloud computing

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April 2015

Department of Computer Science and Engineering

(DCSE)

Dipartimento di Informatica –

Scienza e Ingegneria

(DISI)

University of Bologna, ITALY

antonio.corradi@unibo.it

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���� ������������ � !terminology of cloud

computing is as

clearly and precisely

defined as, well,

a cloud.”

Source:

www.opencloudmanifesto.org

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onne

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maintenance, etc.

Advances in multi-core computer architecture

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on the Internet

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“It starts with the premise that the data services and architecture should be on

servers. We call it cloud computing – they should be in a ‘cloud’ somewhere.

And that if you have the right kind of browser or the right kind of access, it

doesn’t matter whether you have a PC or a Mac or a mobile phone or a

BlackBerry or what have you – or new devices still to be developed – you can

get access to the cloud…”

Dr. Eric Schmidt, Google CEO, August 2006

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IT on demand pricing

Best benefits in a reliable context

Pool of virtualized computer resources

Rapid live providing while demanding

Systems on scaling architecture

on demand,

reliability,

virtualization,

provisioning,

scalability

on demand, opqrs �v��q�sy

Some … Clouds 4

One Cloud is capable of providing IT

resources ‘as a service�

One Cloud is an IT service delivered to

users that have:

• a user interface �� � ¡ ¢£¤ ��£ ¥¦§¨ ¤�¨©ª�©¨£underlying the service transparent to the user

• reduced incremental management costs «�£¦additional IT resources are added

• services oriented management ¬­®¯°±²®±³­²

• massive scalability ´µ¶· ¸ ¹ºµ»¼½ 5

¾

• Solving large problems with parallel computing

• Network-based subscriptions to applications

¿ Offering computing resources as a service

¿ Anytime, anywhere access to IT resources delivered dynamically as a service.

Software as a Service

Utility Computing

Cloud Computing

Grid Computing

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Clo

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§ Grid computing À Sharing of heterogeneous resources (computer, software,

data, memory, computational power,, …) in highly distributed environments with the goal of creating a virtual organization scalable Áby need!)

§ Interfaces (for management), often too fine grained, with low level of abstraction, and non self-contained L

§ Application areas very limited and specific (parallel computation for scientific, engineering scenarios, …) for scientific, engineer

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Some … Clouds 7

§ Virtualization À Technologies for virtualization (either system-based or

hosted), as in a server farm: Vmware, Xen, … § Isolation & personalized infrastructure ×ØÙÚÛÜ SW

platform ÝÞßàß áâã äåæç áããèéèåâáê áëëêèìáéèåâäí § Tool for the efficient management of computing

infrastructures (IBM Tivoli suite, Xen monitoring tools, …)

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Some … Clouds 8

§ Web 2.0 ò Usage of asynchronous protocols not visible to users to

ask only really required info and not the whole web pages: Asynchronous Javascript And XML (AJAX)

ò New ways of using Web services coupled with new applications easier to use, óôõõö÷ôøöùúôû ÷öüýþ and openly available, without requiring any installation ÿbinterested users: new business model, very, very cooperative (Software as a Service J)

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https://www.google.com/hostedhttp://smallbusiness.yahoo.com/email/

www.zimbra.com

many others…

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www.writely.com

www.writeboard.com

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Some … Clouds 9

§ Huge computational and storage capabilities

available from utilities, the same as for energy and

electricity, and on pay-per-use base.

§ “Computing may someday be organized as a

public utility� - John McCarthy, MIT Centennial in

1961

§ Metered billing ./01 234 5607 138 89:;

§ Simple to use interface 73 0tt:99 76: t0/0<=>=71(e.g., plugging into an outlet)

Before Cloud computing: Utility computing

S��#?@�� as a Service (SaaS)

Traditional Software On-Demand Utility

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Plug In, Subscribe

Pay-per-Use

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§ Built for one-to-many delivery over Web

§ Applications not deployed in-house

§ Shared public infrastructure

§ Little customization

§ Subscription fee or advertising-supported

Perpetual license

One-to-few One-to-many

Subscription

Private infrastructure Public infrastructure

Source: IDC, 2006

Time

Software as a Service

]^_`acApplication

Management

Software on Demand

(ASP)

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Hosted Application

Management

SofSofSoftwatwatware re re on on on DemDemDemandandand

(ASP)

d Built for one-to-one delivery or management

§ Applications deployed in-house

§ Dedicated infrastructure/ environments

§ Highly customized

§ One-time license and recurring maintenance or support fee

Some … Clouds 12

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Grid Computing Utility Computing

Software as a Service

Cloud Computing

Some … Clouds 13

ghiijk Cost of IT

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xyyx - Software as a Service

n Software ownership costs pushed to vendor z hardware, software,

system security, disaster recovery, maintenance, monitoring

n Return to core competency { organizations shift resources to core

competencies, vendors focus on managing their SaaS

n More efficient deployment | instant evaluation, more collaboration

between vendor and IT organization, much faster deployments

n Eliminate shelfware & maintenance } pay for what you use

n Always on current version } version-free software means the latest for

the customer

n Modern, Web 2.0 interface { drive technician usage and better customer

interaction with IT

n SaaS homogeneity costs less ~ one version for the vendor to support

means lower costs for everybody

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����������� areas suitable for SaaS

• ERP vertical business ������������� ���� ����������� ���very specific

• General-purpose applications without any adaptation (potentially sharable)

– self-service provisioning and ad-hoc personalization

– applications available to several different users

• Business B2B applications domain specific � no need of third party hosting and involvement

• Customer/Supplier ������������ � applications where most of users and access is

externally to the organization and where ubiquitous access via Web is critical and intrinsic

• Business ������������ even critical� but not the core business ones

Some … Clouds 16

�������� �¡ � -premise Deployment

at the client site

Details

n Full ownership

n Significant implementation

n Customizable

n Difficult to upgrade / maintain

Examples

n HP Service Manager

n BMC Remedy

n CA Service Desk

n EMC Infra

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Customer Data Center

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n Hosted by software

publisher

n Many customers to one

application set

n Thought to be inflexible

Examples

n Salesforce.com

n Workday

n Innotas

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Management

automation

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n Hosted by software publisher

n Customers receive their own

app and database

n Auto-upgrades

n Extensive customization

Examples

n Service-now.com

n InteQ

n Eloqua

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É��É Models

Some increasing resources models for providing some

resources as a service, XaaS

SaaS Software as a Service

å Resources are simple applications available via remote

Web access

PaaS Platform as a Service

å Resources are whole software platforms available for

remote execution, i.e., several programs capable of

interacting with each other

Iaas Infrastructure as a Service

å Resources are intended in a wider and complete way,

from hardware platforms, to operating systems, to

support to final applicationsæ çèçéêêë ìíé ìíîïçéêíðéïíñò up to Cloud Computing Some … Clouds 20

óôõö÷ôõø

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ý þÿB�� ��ÿ �ÿ�Barchitecture:

hardware components

&

software products

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Some … Clouds 21

H�������

I������� !� �� as a Service (IaaS)

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� *+,-./0-1201-3: layer to

enable the distribution of

Cloud services,

typically realized by a

virtualization platform

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PJ���"�$ as a Service (PaaS)

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I������� !� �� as a Service (IaaS)

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&'()'( &'()'( &'()'(

V PJ���"�$W layer to provide

to upper layers a set of

services and components

remotely available

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Some … Clouds 23

H�������

PJ���"�$ as a Service (PaaS)

KMOQM+3+0/ R3-TU23/

I������� !� �� as a Service (IaaS)

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RM,0X.-3 as a Service (SaaS)

Y�!Z[�� Interface \��� Interface V ]%%J[!��["�: layer to

install applications,

to be available via Web

and Internet via Cloud

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Some … Clouds 24

^_`ab_`c

d efghij software to get access to

the system.

Those applications execute on

the client physical platforms

(remote computers) owned by

the final remote user

they can communicate with the

Cloud via the available

interfaces

kl_mno`p as a Service (PaaS)

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|{n`_}m`~�m~`c as a Service (IaaS)

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uq�j��vh as a Service (SaaS)

�_��z{c Interface �}c` Interface

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Some … Clouds 25

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�²³� SaaS and *-aaS examples

SaaS

´µ¶· ¸¹º»¼¶½ ¾½½¿ÀÁ¾¼À¶ÂºÃ Google Apps (Gmail, Google

calendar & docs), Microsoft Window live (Hotmail,

Messenger, …) to search engines, Google, Yahoo,

Several social networks (Facebook, LinkedIn, Twitter, …)

PaaS typically accessed via Web service

ŵÅÀÁ¹º available internally to and interacting with other

applications, as Google App Engine (GAE)Æ Google MapsÆMicrosoft Azure

Iaas some experimental infrastructures

ĹŹµ¾¿ ¹Ç¾·½¿¹ºÈ ÉÀ¼Ê ÅÀµ¼Ë¾¿À̾¼À¶Â º¹µÅÀÁ¹ºÈ Amazon Web

Services (S3), Elastic Computing Cloud (EC2), to several

management and monitoring desktops to control execution

(Sun global desktop, Zimdesk, …)

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Î Google docs, salesForce, … ÏÐÑÒÓÔÕÒÖÑ Ö×Ñ ØÒÕÙ ÚÓÒÑWeb applications (Web 2.0)

Î Google App Engine ÛÜÜÝÞÒ ßÔÔ à×ÝÐ×Òá ÓÖ×ÑâÜã äÜÕmanagement e security, several languages(Python e Java)

Î HP/Yahoo/Intel Open Cirrus Test Bedå virtualized images, Xen, simple SLA console

Î Amazon Elastic Computing – EC2å Amazon WS (SLA), Amazon Machine Image (DB+Software and middleware+OS) e Xen, Dynamo

Î Openstackå virtualized images (DB+Software e middleware+OS), Xen, Swift (object storage), Cinder (block storage), Neutron(virtualized network)

æ IBM Cloudç virtualized images (DB+Software and middleware+OS), Xen, Tivoli (monitoring and management), simple SLA console

Î Microsoft Azureå Microsoft solution

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Infrastructure Perspective

§ How can we provide flexible compute resources

quickly to promote rapid prototyping?

§ How do we deploy applications that scale up t� ���tincreasing demands over time?

§ How do we manage 100,000’s of machines with

minimal human intervention�

§ How can we make the most efficient u�� �� ��� t��compute resources in a data center?

Some … Clouds 29

Reliability and availability

! W� ���� �� �������� �� �"�#� $%"&�'# (��") * �+��) &�third-party companies

, A-./01 23 045.67 89:à24 April 2011), some papers… ; �<=>zon EC2 Outage Hobbles Websites: Worst Cloud Computing

Disaster”

; �<=>zon's lengthy cloud outage shows the danger of complexity”

Security and legislative issues

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! P�Q����'��'R��'�� à where are my data???

(with emerging partial solutions…)

Service management and integration

, TEGGJUJNJBV BE HXIHX@BX SaaS silos

! Y���Z���'�� �[ )'[[����� (��") � ��Q à standard APIs, VMs migration protocols, etc.

Cloud… introduces new problems

\]^_ ` Clouds 30

Typically three models

n Private cloud – enterprise owned or leased

n Community cloud

– shared infrastructure for specific community

n Public cloud – sold to the public, mega-scale infrastructure

n Hybrid cloud � composition of two or more clouds

Some … Clouds 31 \]^_ ` Clouds 32 ab/19

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Community

Cloud Private

Cloud

Public

Cloud

svwxyz {|}~z� Deployment

Models

Service

Models

Essential

Characteristics

Common

Characteristics

�}����x� �� �Service (SaaS)

�|���}x� �� �Service (PaaS)

���x���x~��~x� �� �Service (IaaS)

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�x}ad Network Access ���yz �|���y�y�v ����~x�z ��x�y��

�� �����z ��|�-Service

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³ Four main components: § one Cloud platform, with an externally available interface

accessed via web ´µ ¶µµ·¸¹º´¸ »¼´½ ´½¸ ¹¸º¾ µ¹ ¿¼¹´Àº¾ ¼Á´¸¹Áº¾infrastructure

§ one virtualization infrastructure and the management system for the control, monitoring, and billing for client requests

§ one internal memory system ÂÃÄÅÆÇÈÈÃ ÉÅÇ a database

§ one internal manager ´µ ½ºÁʾ¸ external requests (management, queuing, and controlling)

Cloud Computing software systems have a typical structure based on components ËÌÍË ÎÍÏ ÎÐÑÑÒÏÓÎÍËÔwith each other via well defined interfaces (often Web Services)

Õ Goal and requirements Ö Cost reduction ×ËÐ ÑÓÏÓÑÓØÔ ÙÔÚÛÐÜÑÔÏË ÎÐÝËÞ ÔÏÔßàÜÞ

storage, computing power, …) Ö Scalability on demand áâãäåæâçãä èéêëìãë íê éê îãìéäïíç

way”, all system resources are virtualized as for virtual machine, agreed and granted in SLA (Service Level Agreement

ð Automated provisioning and ease of use ñòóôõôóöcomputing + infrastructure, platform, and SaaS)

Õ Technical areas of intervention Ö Management ×ÝÜÝËem resources, power-saving, …)

ð Interoperability & portability ñ÷øóøù øúúõôûøóôüýþù øý÷virtual machine images)

Ö Measurement and monitoring ×ÙÜÏÍÑÓÎ ÐÏ ÛÓÏÔmonitoring, accounting control, …)

Ö Security (privacy/data control, reputation, …)

Cloud computing …

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Not exactly

for everything J

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Cloud computing today

The Cloud term and its related technologies have

become very common also for non technical users

- Advertising

- Humor

- Buzzword

����� ��� �������� ���� ��� ���� ���� advanced technologies

also very widespread solutions, but also has stimulated a some

directions as guidelines for Global and Local Politics toward the

necessity and the unavoidably of the adoption

• G Cloud in UK

• USA: Federal Cloud (1/4 of total IT expenses)

• UE pushing toward European Cloud

Some … Clouds 36

Complete model of service

S�� roles and offerings a! still not so widely available

Some significant aspects

"#$% & Clouds 38

A taxonomy

"#$% & Clouds 39

Many aspects have been solved, not all of them are, some still hard to tackle • Virtualization

� New forms of resource virtualization

• Differentiated and global resource localization

� Federation and coordination of global resources

• Security, Privacy and SLA adherence

� Verifiable and trusted assurance policies

• Easy Control, handling and management by user

� Easy-to-use and user friendly actions and tools

• Data and QoS management

' self-* and automated system capable of adaptation

• API and platform enhancements

� New platforms e new interaction modes

Some open technological probems

"#$% & Clouds 40

Several directions and guidelines can be applied coming from neighbor areas

• Mobility

• Green e sustainability

• Novel business models

• Open-source and globally-available resources

• Peculiar legal aspects

Related Issues and Areas

L( )(*+,-,./( 0-,124 5 41 6789 : Clouds 41

Cloud computing: pros and cons

6789 : Clouds 42

Integration

Cloud : perception and challenges

Security

6789 : Clouds 43

Cloud as a new sector, unavoidable in expansion and spreading, but acceleration can be favored by standard acceptation

• Clarity about new roles and responsibility

• Open source standard and implementations

• Integration with existing protocols (mobile …)

• Supports for sustainability

• Global and local legal clarity

• Ties with other areas:

Big Data, Open Data, and Smart City

Standard: a necessity

6789 : Clouds 44

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� GHI clouds

are disclosed

into the sky!

Thanks for

your

attention!

Some … Clouds 45