1/10/2011. Topics. What is the Cloud? Cloud Computing

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1 Cloud Computing Topics 1. What is the Cloud? 2. What is Cloud Computing? 3. Cloud Service Architectures 4. History of Cloud Computing 5. Advantages of Cloud Computing 6. Disadvantages of Cloud Computing 7. Cloud Deployment Architectures Images courtesy of Majd F. Sakr or from Wikipedia unless otherwise noted. What is the Cloud? The term cloud comes from the cloud icon used in network diagrams. Today the cloud is a large set of hardware and software hosted in a data center provided as a utility computing service. 1

2 What is Cloud Computing? Cloud computing is a model for enabling convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction. NIST definition of Cloud Computing Software as a Service (SaaS) Web-accessible applications Platform as a Service (PaaS) Platform for custom software development Infrastructure as a Service (IaaS) Virtual machines, storage, and networks Cloud Service Architectures Cloud Service Architectures as Layers 2

3 Cloud Service Architectures by User Cloud Service Models Abstraction Layers Cloud Service Models form a Continuum 3

4 Software as a Service Clients use provider s applications running on cloud infrastructure via the web. Client can configure application, but not network, OS, storage, etc. SaaS Architectures Platform as a Service Clients can deploy client-developed or acquired applications that were created using programming tools and languages supported by provider. 4

5 Infrastructure as a Service Client can provision processing, storage, networks, and other basic computing resources on which the client can run arbitrary software. IaaS enabled by Virtualization Allows easy sharing of hardware resources. Produces higher utilization rates. IaaS enabled by Virtualization Linux BSD W2k8 Virtual Machines Physical Machine 5

6 Douglas Parkhill, 1966 History of Cloud Computing Evolution of Cloud Computing Nellutla and Teoh, IBM,

7 Why Cloud Computing Now? Data-intensive Applications Data Center Complexity and Cost Increase Network Capacity and Availability Rising Energy Costs Flexibility Scalability Cost Maintenance Utilization Power Cloud Computing Advantages Flexibility Software: any platform Access: access from any host on Internet Speed: Deploy infrastructure quickly 7

8 Scalability Controlled via software No time required to purchase, delivery, install hardware Add or remove resources almost instantly Can scale up and down to meet demand Illusion: unlimited resources available on demand Cost Pay-as-you-go model No capital expenditures Small companies can tap high end infrastructure Maintenance Maintenance responsibility of cloud provider IaaS: hardware, network PaaS: software stack, OS, hardware, network SaaS: everything Can use to reduce size of IT department 8

9 Utilization Typical DC utilization around 20% Must have enough capacity for peak usage times Different customers have different usage patterns Power Lower power consumption Consolidation of servers Virtualization increases usage Large scale highly efficient DCs Lower power costs DCs built near cheap power sources Security Privacy Vendor lock-in Migration Cloud Computing Disadvantages 9

10 Security Third party stores organization data so Attackers can target communications between cloud provider and client Attackers can target cloud provider directly Privacy Cloud providers can monitor communications between client and provider Cloud providers can read client s data if it is not always encrypted Privacy protections depend on location and you may not know where your data is located Vendor Lock-In Most cloud APIs are proprietary Cloud providers offer different features It can take weeks to move data out of a cloud 10

11 Migration Systems already need to be consolidated and ready to be virtualization before migration Slow WAN speeds lead to slow migrations Cloud Deployment Architectures Cloud Deployment Architectures 11

12 Public Clouds Cloud is located off-site Third party provider owns and maintains Pay as you go service Private Clouds Community Cloud 12

13 Hybrid Clouds Combined cloud environment with multiple internal and/or external providers. May automatically use public cloud resources when private cloud resources are used at full capacity. Key Points Cloud computing definitions Cloud service architectures Software as a Service (SaaS) Platform as a Service (PaaS) Infrastructure as a Service (IaaS) Advantages and disadvantages of cloud computing Cloud deployment architectures Public Private Community Hybrid 13