Clearing the Clouds Understanding cloud computing Ali Khajeh-Hosseini ST ANDREWS CLOUD COMPUTING CO-LABORATORY

There are many definitions and they all differ Simply put, cloud computing is a model for delivering IT as a Service. Clouds refer to the actual data centres that house the hardware and software US National Institute of Standards and Technology working definition: Cloud computing has Five characteristics Three service models Four deployment models 2 Cloud computing Clearing the clouds, November 2009

1.On-demand self-service: you can start using computing resources at anytime without needing human interaction with cloud service providers. Computing resources can be storage, processing, memory, network bandwidth, VMs... 2.Broad network access: you can access those resources over the network using laptops, mobiles phones etc. 3.Resource pooling: the computing resources are shared by multiple users (multi-tenancy) 4.Rapid elasticity: you can scale up or down the amount of resources that youre using very quickly 5.Measured service: resource usage is metered by measuring your storage, CPU hours, bandwidth usage etc. Clearing the clouds, November Characteristics

Infrastructure as a Service – Low level of abstraction, most flexible, dealing with virtual machines Platform as a Service – High level of abstraction, less flexibility, dealing with your application code and your providers APIs Software as a Service – Using software that others have developed and offer as a service over the web Clearing the clouds, November Service Models

Private cloud: controlled and used by one organization Community cloud: used by several organizations Public cloud: available to the general public Hybrid cloud: mixture of the above, allows cloud bursting Clearing the clouds, November Deployment Models

St Andrews Cloud Computing Co-laboratory launched in April 09 Local investment of about £0.5 million covering – PhD Studentships – Experimental hardware platform – Technical support Our aim was to explore the research potential of CC bringing together researchers in distributed systems, high-performance computing and systems engineering Clearing the clouds, November StACC

The StACC private cloud is now operational – 10 servers (Cloud controller, storage server, 8 * 4 core general purpose servers) – Running Eucalyptus open source software Objectives – To understand whats involved in setting up and running a cloud (more than you might think!) – To provide an experimental platform that we can measure – To provide us with a platform that we can extend (and break) StACC Experimental Cloud Clearing the clouds, November 20097

8 Cloud Service Consumers Software as a Service Platform as a Service Infrastructure as a Service Public Clouds Public Clouds Private Clouds Private Clouds Community Clouds Community Clouds Hybrid Clouds Hybrid Clouds Is it cheaper? Is it secure? How will it effect my work? We did an extensive literature survey to see if we can find out the answers...

Should I lease or buy? Walker modelled the cost of a CPU hour when purchased as part of a server cluster and compared it with Amazon EC2 2 scenarios, purchasing: – a 60,000 core HPC cluster – a compute blade rack consisting of 176 cores Model showed that its cheaper to buy in both scenarios assuming that CPU utilization is very high and electricity is cheap Good first step but far too narrow in scope, what about costs of housing the infrastructure, installation and maintenance, staff, storage and networking? Clearing the clouds, November Costs E. Walker, The Real Cost of a CPU Hour, 2009

Deelman et al. used simulation to calculate the cost of running a data-intensive astronomy application on Amazons cloud Highlighted the potentials of using cloud computing as a cost- effective deployment option for data-intensive scientific application Assumed the cost of running instances on AWS EC2 are calculated on a dollar-per-CPU-second basis, i.e. they normalised the costs But, AWS charge on a dollar-per-CPU-hour basis and charge for a full hour even for partial hours. So launching 100 instances for 5 minutes would cost 100 CPU hours Makes a significant difference in costs Clearing the clouds, November Costs E. Deelman, G. Singh, M. Livny, B. Berriman, J. Good, The cost of doing science on the cloud: the Montage example, 2008

Kondo et al. investigated the costs of using cloud computing for desktop grid projects such as They found that deploying the servers used for the project on Amazons cloud would cost 40% less than using their universitys data centre Didnt include upfront server purchasing costs or staff costs Cloud computing would look even more attractive if they did Clearing the clouds, November Costs D. Kondo, B. Javadi, P. Malecot, F. Cappello, D. P. Anderson, Cost-benefit analysis of Cloud Computing versus desktop grids, 2009

So is it really cheaper? Not really sure, it all depends on the specific scenario and what you include in your calculations Were developing a tool to help users decide for themselves... Clearing the clouds, November Costs

Security concerns are often mentioned in cloud computing but not much research has been done to address them The Cloud Security Alliance has published a set of security guidelines in the form of problem statements and issues that need to be considered by users Most concerns are about loss of control over physical hardware which then lead on to legal issues... Clearing the clouds, November Security

Most legal issues are related to the clouds physical location, which determine its jurisdiction Amazon have data centres in 2 regions (US and Europe) so they can deal with these issues But the clouds nature means that users dont know (or care) about this information: its all in the cloud Location is important because cloud computing increases the control of governments and corporations over resources*. Cloud computing brings together vast amounts of data and computing resources in centralised data centres, compared to how they are currently hosted in geographically dispersed locations Its unlikely that these jurisdiction issues will stop the use of cloud services Clearing the clouds, November Legal Issues * P. T. Jaeger, J. Lin, J. M. Grimes, S. N. Simmons, Where is the cloud? Geography, economics, environment, and jurisdiction in cloud computing, 2009

How will cloud computing effect the work of IT departments? Their authority has been diminishing over the last few decades, from mainframes to PCs Cloud computing is going to decrease their authority further Users are turning into choosers * who can replace the services provided by the IT department with service offered in the cloud Clearing the clouds, November Effects on Work * R. Yanosky, From Users to Choosers: The Cloud and the Changing Shape of Enterprise Authority, 2008

To study these issues, we performed a case study examining the relative costs of migrating from a locally provided host to a host provided on Amazon The system studied was a fairly small data acquisition IT system from the Oil & Gas industry. The system had a contract value of £104,000 and was deployed in a local data centre Our focus was socio-technical – what are the human and organisational issues that influence such decisions Clearing the clouds, November Case Study

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Case Study Clearing the clouds, November Infrastructure costs over 5 years Around 55% cheaper 218 support calls over 5 years 20% of them would be eliminated Backup, power and network issues would be Amazons responsibility In-house Cloud £57,000£25,000 Support Issue

Interviews Clearing the clouds, November We took these findings and presented them to various people in the company and interviewed them Technical manager: – It looks attractive – We would lose leverage over support contracts – Concerned about security and protection of virtual machines – Some corporations veto data going over port 80 Support staff: – Very negative about cloud computing – Feel threatened – Dont want to lose control over hardware

Project manager: – Hard to sell this idea, theres no data centre to show clients – Difficult to alter corporate security policies – Easier to manage cash flow – Reduces required skill-set and overheads Business development manager: – We are under pressure to reduce electricity usage – It presents new opportunities for us, e.g. running training courses in the cloud Interviews Clearing the clouds, November

Cloud computing has sparked a huge interest in the IT industry Many organizations are thinking about migrating their systems to the cloud. During this period, many migration decisions need to be made, what to keep in-house, what to migrate These arent simple decisions and there are a range of issues that need to be considered when making these decisions: economic, technical, organizational, risks etc. We are developing a decision support system to help people make those decisions… Clearing the clouds, November Decision Support System

Cloud computing is still in its early days We are currently at the start of a transition period, the shift towards cloud computing could take many years Not much research has been done about issues effecting cloud service consumers Clearing the clouds, November Summary