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Virtualization and Cloud

Jonathan Gershater

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Top Stories by Jonathan Gershater

BigData (and Hadoop) are buzzword and growth areas of computing; this article will distill the concepts into easy-to-understand terms. As the name implies, BigData is literally "big data" or "lots of data" that needs to be processed. Lets take a simple example: the city council of San Francisco is required to take a census of its population - literally how many people live at each address. There are city employees who are employed to count the residents. The city of Los Angeles has a similar requirement. Consider are two methods to accomplish this task: 1. Request all the San Francisco residents to line up at City Hall and be prcessed by the city employees. Of course, this is very cumbersome and time consuming because the people are brought to the city hall and processed one by one - in scientific terms the data are transfered to the processing node. The people have ... (more)

Brief Summary of IaaS, PaaS, SaaS

In this posting, I summarize my prior three posts on the three cloud computing offerings: Infrastructure as a Service (IaaS), Platform as a Service (PaaS) and Software as a Service (SaaS). I concentrate how the three offerings differ with respect to flexibility, maintenance and portability. One of the greatest challenges companies face when moving to the cloud is security. Thus I will devote an entire blog post in the future, to security concerns. Flexibility How much flexibility do you have with each offering? What can you change or modify within each cloud offering to suit you... (more)

Security Is Not the Only Barrier to Cloud Adoption

In his 90 minute keynote address at the AWS re:Invent conference, Andy Jassy quite unabashedly gave these reasons for using AWS versus a private cloud, (at the 32 minute mark) : So public cloud adoption should be a no-brainer, right? Oh wait, but Andy omitted security in the public cloud - how can I trust that my customers' sensitive data is secure in the public cloud? Been there, heard that before. I agree, the message wears thin that enterprise businesses are apprehensive to store sensitive customer data in the public cloud, and thus hesitant to adopt the cloud at all. (By th... (more)

A Comparison Between OpenStack and VMware vCloud IaaS Offerings

I previously wrote a review of  the Microsoft Azure public cloud and included a comparison between Azure and AWS (Amazon Web Services) and will now compare OpenStack and VMware vCloud. For a review of IaaS (Infrastructure as a Service) see my blog post and video. This table provides a simple and high level comparison of OpenStack and vCloud. Feature OpenStack VMware vCloud Virtualization layer Type 2 virtualization - Libvirt layered on top of Linux. Supports various hypervisors: XEN, KVM, HyperV... Type 1 virtualization - bare metal; vSphere hypervisor only. Management Open API... (more)

Cloud Computing Easily Understood - SaaS

In prior blog posts, I described Infrastructure as a Service (IaaS) and Platform as a Service (PaaS). To recap: If I use IaaS I get servers onto which I can load software and applications which I then maintain, though I don't need to maintain the hardware. I can customize the applications and software running on the servers, at will. If I use PaaS, I get a platform of ready to use web servers, application servers, databases etc. I write my own software application and host it at the PaaS provider. I maintain the software I write, but not the application servers, databases or ha... (more)