![[michael-dziedzic-nLFqr9Mr9H8-unsplash.jpg ]] Photo by [Michael Dziedzic](https://unsplash.com/@lazycreekimages?utm_source=unsplash&utm_medium=referral&utm_content=creditCopyText) on [Unsplash](https://unsplash.com/photos/yo43ZPnPWt8?utm_source=unsplash&utm_medium=referral&utm_content=creditCopyText) *Multi-tenancy in cloud means sharing of resources (such as computing, networking, storage) and services for multiple consumers and client organizations (tenants).* Let’s think about it. Speaking pure economically, a cloud provider is able to minimize the infrastructure and labor costs as well as spread them across all customers with similar needs. Total Cost of Ownership #TCO is certainly well known business driver and indicates great interest of all business stakeholders looking forward to receive services for free. Well, this is possible today only on certain level and with limited elasticity. The reason is shockingly very simple: We don’t have platform which will enable dynamic sharing and isolation on all levels of XaaS (Anything as a Service) stack. > Chris Anderson, author of the book “Free – The Future of a radical price”, defined ten principles of “Abundance Thinking”. First principle is “If it’s digital, sooner or later it’s going to be free…” If this is the case, then absolute Multi-tenancy is inevitable. Anyway, what’s the history of multi-tenant architectures? We can start with well-known Mainframes which shared quite a lot considering that particular time. What about P2P networks or science projects (SETI@HOME) running on computers and game consoles (Playstation3)? Or even Botnets? Distributed Computing and Grid Computing were certainly pioneers with open protocols and atomized units sharing computing power, storage and network. So, maximal sharing at all levels means absolute multi-tenancy, something we didn’t invite yet and it’s far more complicated than specification of various Multi-tenancy models. I tend to believe, this is a key to Massive Computing without boundaries, running inside Cloud Computing and utilizing Stream Computing. There are other, equally important characteristics describing massive computing - here is my list: - Code is Everywhere – Same code (on logical level) runs everywhere serving as a foundation platform for services running above - It’s Replicable – Creates Virtual Environment from Image at any location and act as Independent, Atomized unit - It’s Adaptable – Uses Open API with dynamic specification - Supports Service Abstraction and Recursion abilities - Content is Unique (de-duplication) and identified by distributed metadata repositories - Semantic standardization – metadata are semantic enabled - Each Atomized Unit runs Autonomously and depends only on Task prioritization - Push and Pull Methods based on Service Subscription - Unit Services represents various XaaS encapsulated components - Service Logic has various levels based on XaaS Service ![[Pasted image 20230708135116.png|Figure 1: Multi-tenancy reference model]] Simple, #multi-tenancy reference model could also help to recognize our options today and open the doors for tomorrow to standardize shared and isolation levels. ## Related to [[Sharing and Isolation levels within Multi-tenancy reference model]] [[How to visualize XaaS Patterns]]