ABC of Cloud Computing
Cloud computing is an umbrella term for many concepts, here is a collection of some of the key concepts under that umbrella and the meaning of those terms
ACLs
Stands for Access Control List. For a given cloud resource, an ACL defines limits on who can connect to a resource and at what port.
Buckets
Unstructured storage areas, bucket names have to be unique, even across accounts. You can store a number of things in bucket ranging from deployment artifacts such as jar files, war files, ear files or static content like tar files containing pretty much anything. Most buckets provide very high degree of availability with relatively low-cost storage solution.
Compute
Fancy way of saying a Linux or Windows server. Compute can be rented on a per-hour basis or for a longer period of time. Need a Linux server with 4 vcores and 8 GB of RAM? Cloud vendors have a console to go and click on a few buttons and you are generally on your way to have a compute instance ready for you in a few minutes.
Elastic
Most companies have traffic that follows one or more patterns. If you are an online TV content company, you most likely have customers that watch more content during prime time and less during work hours (hopefully :) ). You want to rent compute power and have it be elastic. Elastic means it can grow and shrink easily as the demand for compute power goes up and down.
Firewall
Firewalls come in all flavors. Firewalls can range from hardware solutions to IDS systems to software based solutions. For most cloud applications, you will at least have a software solution that blocks undesired connections to your servers. You want to start with a black-list approach. With black-list, you have all ports blocked by default. You set up a whitelist to only allow connections that you application needs to function.
Instance
Usually is used, almost interchangeably, to say a compute instance or a server.
IaaS
Infrastructure as a Service, Means the cloud provider provides the hardware and the OS. You configure the application stack including runtime needed to run your application.
PaaS
Platform as a Service. Means the cloud vendor provides the hardware, OS and the runtime needed to run your application. You bring the app.
https://www.heroku.com/ https://cloud.google.com/appengine/ are good examples
SaaS
Software as a Service. Turn Key solution. You rent the software solution usually on a per month basis.
http://www.adobe.com/creativecloud.html is an example.
Serverless
Serverless is a hot trend in Cloud computing at the moment. This means that the development team does not have to configure a server to run their code. They simply take the code they want to run and tie to an event being fired. Most cloud vendors have these features in beta or early GA. There are also limitations on what use-cases this can solve. Currently, people use this for simple tasks. Event can be somthing like when a file is uploaded or a web request is made.
VPN
Virtual Private Network. Used to connect the internal data center of an organization to one or more public cloud vendors. This can also be used to create a connection from infrastructure hosted on one cloud vendor to another. It is not desirable to route private or sensitive traffic between servers over an unprotected channel and hence a VPN solution is used to create a secure tunnel between the two endpoints.
