Horizontal scaling means that you scale by adding more machinesinto your pool of resources whereasVertical scaling means that you scale by adding more power (CPU, RAM) to an existing machine.

An easy way to remember this is to think of a machine on a server rack, we add more machines across thehorizontaldirection and add more resources to a machine in theverticaldirection.

With horizontal-scaling it is often easier to scale dynamically by adding more machines into the existing pool --- Vertical-scaling is often limited to the capacity of a single machine, scaling beyond that capacity often involves downtime and comes with an upper limit.

The primary use case for using Web Application Firewall (WAF) in OCI is to filter malicious web traffic and protect internet-facing and internal applications from attacks. WAF is a cloud-based, PCI-compliant, global web application firewall service that monitors and controls access to web applications based on predefined rules and threat intelligence. WAF can block common web application attacks such as cross-site scripting (XSS), SQL injection, remote file inclusion, etc., as well as bot traffic, geographic restrictions, rate limiting, etc.WAF can protect any internet-facing endpoint or internal application by attaching WAF policies to enforcement points such as load balancers or web application domain names10

Components of IAM

RESOURCE

The cloud objects that your company's employees create and use when interacting with Oracle Cloud Infrastructure. For example: compute instances, block storage volumes, virtual cloud networks (VCNs), subnets, route tables, etc.

USER

An individual employee or system that needs to manage or use your company's Oracle Cloud Infrastructure resources. Users might need to launch instances, manage remote disks, work with your virtual cloud network, etc. End users of your application are not typically IAM users. Users have one or more IAM credentials (seeUser Credentials).

GROUP

A collection of users who all need the same type of access to a particular set of resources or compartment.

DYNAMIC GROUP

A special type of group that contains resources (such as compute instances) that match rules that you define (thus the membership can change dynamically as matching resources are created or deleted). These instances act as 'principal' actors and can make API calls to services according to policies that you write for the dynamic group.

NETWORK SOURCE

A group of IP addresses that are allowed to access resources in your tenancy. The IP addresses can be public IP addresses or IP addresses from a VCN within your tenancy. After you create the network source, you use policy to restrict access to only requests that originate from the IPs in the network source.

COMPARTMENT

A collection of related resources. Compartments are a fundamental component of Oracle Cloud Infrastructure for organizing and isolating your cloud resources. You use them to clearly separate resources for the purposes of measuring usage and billing, access (through the use of policies), and isolation (separating the resources for one project or business unit from another). A common approach is to create a compartment for each major part of your organization. For more information, seeSetting Up Your Tenancy.

TENANCY

The root compartment that containsallof your organization's Oracle Cloud Infrastructure resources. Oracle automatically creates your company's tenancy for you. Directly within the tenancy are your IAM entities (users, groups, compartments, and some policies; you can also put policies into compartments inside the tenancy). You place the other types of cloud resources (e.g., instances, virtual networks, block storage volumes, etc.) inside the compartments that you create.

POLICY

A document that specifies who can access which resources, and how. Access is granted at the group and compartment level, which means you can write a policy that gives a group a specific type of access within a specific compartment, or to the tenancy itself. If you give a group access to the tenancy, the group automatically gets the same type of access to all the compartments inside the tenancy. For more information, seeExample ScenarioandHow Policies Work. The word 'policy' is used by people in different ways: to mean an individual statement written in the policy language; to mean a collection of statements in a single, named 'policy' document (which has an Oracle Cloud ID (OCID) assigned to it); and to mean the overall body of policies your organization uses to control access to resources.

HOME REGION

The region where your IAM resources reside. All IAM resources are global and available across all regions, but the master set of definitions reside in a single region, the home region. You must make changes to your IAM resources in your home region. The changes will be automatically propagated to all regions. For more information, seeManaging Regions.

FEDERATION

A relationship that an administrator configures between an identity provider and a service provider. When you federate Oracle Cloud Infrastructure with an identity provider, you manage users and groups in the identity provider. You manage authorization in Oracle Cloud Infrastructure's IAM service. Oracle Cloud Infrastructure tenancies are federated with Oracle Identity Cloud Service by default.

https://docs.cloud.oracle.com/en-us/iaas/Content/Identity/Concepts/overview.htm

Oracle Dedicated Region Cloud @Customer is a fully managed cloud region that brings all Oracle Cloud Infrastructure services and Oracle Fusion Cloud Applications, including Oracle Autonomous Database and SaaS applications, to customer datacenters, starting from only $500K a month1

https://education.oracle.com/en/learning-paths/trackp_OCIF2023CA