# IT Infrastructure Model

![IT-Infrastructure-model.png](https://159067695-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-Liw2CGymV5kmKZxZvtB%2Fuploads%2Fgit-blob-8f6a76894bd6ef30c224b011524c9295c30e5199%2FIT-Infrastructure-model.png?alt=media)

* In this model processes use information,
* this information is stored and managed using applications.
* Applications need application platforms and infrastructure to run.
* All of this is managed by various categories of systems management.

## Process/Information block

* Organizations implement business processes to fulfil their mission and vision.
  * Business features, that are implemented into the software system, deployed and used by the user/business
* processes are organization specific
  * example, some business processes in an insurance company could be:
    * claim registration, claim payment, and create invoice.
* Business processes create and use information (update, transform, validate, combine, apply rules to).
  * Information is typically entered, stored and processed using applications
* **Functional management** is the category of systems management that ensures the system is configured to perform the needed business functions

## Applications building block

* Includes 3 types:
  * Client applications typically run on end user devices like PCs and laptops.
    * Examples:
      * web browsers
        * applications running in web browser ie websites
      * word processors
      * email clients
      * games
  * Office applications provide standard server based applications most organizations use.
    * Examples:
      * mail servers
      * portals
      * collaboration tools
      * instant messaging servers.
    * Most organizations run these office applications more or less out of the box.
  * Business specific applications are applications that are typically highly customized or custom built.
    * Commonly known as enterprise applications
    * Examples:
      * Customer Relationship Management (CRM)
      * Enterprise Resource Planning (ERP)
      * Supervisory Control And Data Acquisition (SCADA) systems
      * applications that are created for a specific business process
        * like an insurance management system
* Applications management is responsible for the configuration and technical operations of the applications.

## Application Platform building block

* Most applications need some additional services, known as application platforms, that enable them to work
* Types of services
  * Front-end servers
    * are typically web servers that provide end users with interactions to applications by presenting application screens in web browsers.
    * like Apache HTTP Server and Microsoft Internet Information Services – IIS
  * Application servers
    * act as containers running the actual application.
    * Examples
      * Java or .Net application servers
      * frameworks like IBM WebSphere, Apache Tomcat, Red Hat JBoss, and Windows .Net
  * **Connectivity** entails:
    * FTP servers
    * Extraction
    * Transformation
    * Load (ETL) servers
    * Enterprise Service Buses (ESBs)
      * like Microsoft BizTalk, the TIBCO Service Bus, IBM MQ, and SAP NetWeaver PI
  * **Databases**, also known as database management systems (DBMSs),
    * provide a way to store and retrieve structured data.
      * Examples are Oracle RDBMS, IBM DB2, Microsoft SQL Server, PostgreSQL, and MySQL.
* Application platforms are typically managed by systems managers specialized in the specific technology

## Infrastructure building blocks

* Types
  * End User Devices
    * are the devices used by end users to work with applications,
    * like PCs, laptops, thin clients, mobile devices, and printers.
  * **Operating Systems** are collections of programs that manage a computer’s internal workings: its memory, processors, devices, and file system.
  * **Compute** are the physical and virtual computers in the datacenter, also known as servers.
  * **Storage** are systems that store data.
    * They include hard disks, tapes, Direct Attached Storage (DAS), Network Attached Storage (NAS), and Storage Area Networks (SANs)
  * **Networking** connects all components.
    * Includes routers, switches, firewalls, WANs (wide area networks), LAN, dial-in, internet access, and VPNs (Virtual Private Network), and (on the network application level) relatively simple services like DNS, DHCP, and time services, necessary for the infrastructure to work properly.
  * **Datacenters** are locations that host most IT infrastructure hardware.
    * Include facilities like uninterruptible power supplies (UPSs), Heating, Ventilation, and Air Conditioning (HVAC), computer racks, and physical security measures
* Infrastructure management includes processes like ITIL and DevOps, and tools like monitoring, backup, and logging

## Non functional attributes (NFA)

* Cross cutting concerns, spread over multiple blocks
* An IT system does not only provide functionality to users
  * ie provide this business function like buy a product
* functionality is supported by non-functional attributes
* Non-functional attributes are the effect of the configuration of each IT system component, both on the infrastructure level and above.
* The many NFAs, but the main ones that apply to all systems (but different levels for differetn systems ) are availability, performance, and security