Cloud Computing

2020/2021

CLOUD COMPUTING – APPUNTI

CORSO LAUREA MAGISTRALE – CLOUD COMPUTING 1

Sommario

1. INTRODUZIONE AL CLOUD COMPUTING ................................................................................................. 7

1.1. Definizione Cloud Computing ........................................................................................................... 7

1.2. Business and Innovation ................................................................................................................... 7

1.2.1. Business driver .......................................................................................................................... 7

1.2.2. Capacity planning ...................................................................................................................... 7

1.2.3. Cost reduction ........................................................................................................................... 8

1.2.4. Organizational agility ................................................................................................................ 8

1.2.5. Technology Innovation ............................................................................................................. 8

1.3. Basic Concepts................................................................................................................................... 8

1.4. Goal e Risk ......................................................................................................................................... 9

2. FONDAMENTI DEL CLOUD COMPUTING ................................................................................................ 10

2.1. Ruoli ................................................................................................................................................. 10

2.2. Limiti ................................................................................................................................................ 11

2.3. Caratteristiche del cloud ................................................................................................................. 11

2.3.1. On demand usage (when) ....................................................................................................... 11

2.3.2. Ubiquitous acces (where) ............................................................................................................. 11

2.3.3. Multitentancy (how) ..................................................................................................................... 11

2.3.4. Elasticity (how) .............................................................................................................................. 11

2.3.5. Mesuread usage (how much) ....................................................................................................... 11

2.3.6. Resilency (how reliable) ................................................................................................................ 11

2.4. Cloud Delivery models .................................................................................................................... 11

2.4.1. Infrastructure-as-a-Service ..................................................................................................... 12

2.4.2. Platform-as-a-Services .................................................................................................................. 12

2.4.3. Software-as-a-Services ................................................................................................................. 12

2.4.4. Function-as-a-Services .................................................................................................................. 12

2.4.5. Combinazioni di modelli ............................................................................................................... 12

2.4.6. Altri modelli .................................................................................................................................. 13

2.5. Cloud Deployments model ............................................................................................................. 13

3. KEY TECHNOLOGIES ................................................................................................................................ 13

3.1. Broadband network e internet architecture .................................................................................. 14

3.2. Data center technology .................................................................................................................. 14

3.3. Virtualizzation technology ................................................................................................................... 15

3.3. Web technology .............................................................................................................................. 15

3.5. Multitenant technology ....................................................................................................................... 15

3.6. Service technology ............................................................................................................................... 16

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3.7. Use Case: Social Security Public IT Company ...................................................................................... 16

4. CLOUD COME PARADIGM SHIFT ............................................................................................................ 17

4.2. Paradigm shift: revolution .............................................................................................................. 18

4.2.1. Social Paradigm Shift .............................................................................................................. 18

4.2.2. Work Paradigm Shift ............................................................................................................... 19

4.2.3. Business Paradigm Shift .......................................................................................................... 19

5. PRICE AND VALUE MODELS .................................................................................................................... 20

5.2. Introduzione .................................................................................................................................... 20

5.3. Price models .................................................................................................................................... 20

5.3.1. Utility price models ................................................................................................................. 20

5.3.2. Service price models ............................................................................................................... 21

5.3.3. Performance price models ...................................................................................................... 21

5.3.4. Marketing-oriented price models .......................................................................................... 22

5.3.5. Hybrid price models ................................................................................................................ 22

5.4. Value Models .................................................................................................................................. 22

5.4.1. Opereting expenses ................................................................................................................ 22

5.4.2. User demand Flexibility .......................................................................................................... 23

5.4.3. Price flexibility ......................................................................................................................... 23

5.4.4. Agility for time-to-market ...................................................................................................... 23

5.4.5. Location flexibility ................................................................................................................... 24

5.4.6. Asset optimization .................................................................................................................. 24

5.4.7. Profit Margin ........................................................................................................................... 24

5.5. Financial metrics ............................................................................................................................. 25

5.5.1. Payback method ..................................................................................................................... 25

5.5.2. Net present value (NPV) ......................................................................................................... 25

5.5.3. Return on investment (ROI).................................................................................................... 25

5.5.4. Time to market (TTM) ............................................................................................................. 25

6. CLOUD SECURITY ..................................................................................................................................... 25

6.2. Threat agents .................................................................................................................................. 26

6.3. Minacce del Cloud security ............................................................................................................. 27

6.3.1. Intercettazione del traffico ..................................................................................................... 27

6.3.2. Maliciuos intermediat ............................................................................................................. 27

6.3.3. Denial of service ...................................................................................................................... 27

6.3.4. Autorizzazione insufficiente ................................................................................................... 27

6.3.5. Attacco di virtualizzazione ...................................................................................................... 27

6.3.6. Overlapping trusted boundaries ............................................................................................ 28

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6.4. Considerazioni ................................................................................................................................. 28

6.4.1. Flawed implementation .......................................................................................................... 28

6.4.2. Security policy disparity .......................................................................................................... 28

6.4.3. Contratti e SLA ........................................................................................................................ 28

6.5. Risk Management ........................................................................................................................... 28

6.5.1. Risk Assestment ...................................................................................................................... 29

6.5.2. Risk Treatment ........................................................................................................................ 29

6.5.3. Risk Control ............................................................................................................................. 29

6.5.4. Security Conservation principle .............................................................................................. 29

6.5.5. Risk management fasi ............................................................................................................. 29

6.6. Case Study ....................................................................................................................................... 30

7. CLOUD COMPUTING MECHANISMS ....................................................................................................... 31

7.1. Cloud Infrastructure Mechanisms .................................................................................................. 31

7.1.2. Virtual Server .......................................................................................................................... 33

7.1.3. Cloud Storage Device .............................................................................................................. 33

7.1.4. Cloud Usage Monitor .............................................................................................................. 34

7.1.5. Resource Replication .............................................................................................................. 35

7.1.6. Ready Made Environment ...................................................................................................... 35

7.1.7. Mapping .................................................................................................................................. 36

7.2. Specialized Cloud Mechanisms ....................................................................................................... 36

7.2.1. Automated Scaling Listener .................................................................................................... 37

7.2.2. Load Balancer .......................................................................................................................... 37

7.2.3. SLA Monitor............................................................................................................................. 38

7.2.4. Pay-per-use Monitor ............................................................................................................... 39

7.2.5. Audit Monitor ......................................................................................................................... 40

7.2.6. Failover System ....................................................................................................................... 40

7.2.7. Hypervisor ............................................................................................................................... 40

7.2.8. Resource Cluster ..................................................................................................................... 41

7.2.9. Multi-device Broker ................................................................................................................ 42

7.2.10. State Management Database ................................................................................................. 42

7.2.11. Mapping .................................................................................................................................. 42

7.3. Cloud Management Mechanisms ................................................................................................... 43

7.3.1. Remote Administrator System ............................................................................................... 43

7.3.2. Resource Management System .............................................................................................. 43

7.3.3. SLA Management System ....................................................................................................... 43

7.3.4. Billing Management System ................................................................................................... 43

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7.3.5. Mapping .................................................................................................................................. 44

7.4. Cloud Security Mechanisms ............................................................................................................ 44

7.4.1. Encryption ............................................................................................................................... 44

7.4.2. Hashing .................................................................................................................................... 44

7.4.3. Digital Signature ...................................................................................................................... 44

7.4.4. Public Key Infrastructure ........................................................................................................ 44

7.4.5. Identity and Access Management .......................................................................................... 45

7.4.6. Single Sign-On (SSO)................................................................................................................ 45

7.4.7. Cloud-based Security Groups ................................................................................................. 45

7.4.8. Hardened Virtual Servers Images ........................................................................................... 45

8. CLOUD COMPUTING ARCHITECTURES ................................................................................................... 45

8.1. Fundamental Architectures ............................................................................................................ 46

8.1.1. Workload distribution ............................................................................................................ 46

8.1.2. Resourse Pooling ..................................................................................................................... 46

8.1.3. Dynamic Scalability ................................................................................................................. 46

8.1.4. Elastic Resource capacity ........................................................................................................ 47

8.1.5. Service load balancing ............................................................................................................ 47

8.1.6. Cloud bursting ......................................................................................................................... 48

8.1.7. Elastic disk provisioning .......................................................................................................... 48

8.1.8. Redundant storage ................................................................................................................. 49

8.2. Advanced Architectures .................................................................................................................. 50

8.2.1. Hypervisor Clustering .............................................................................................................. 50

8.2.2. Load Balanced Virtual Servers ................................................................................................ 50

8.2.3. Non-disruptive Svc Relocation ............................................................................................... 51

8.2.4. Zero Downtime ....................................................................................................................... 51

8.2.5. Cloud Balancing ........