Explanation
Oracle Functions Concepts:
This topic describes key concepts you needto understand when using Oracle Functions.
Applications:
In Oracle Functions, an application is:
1. a logical grouping of functions
2. a common context to store configuration variables that are available to all functions in the application
3. a way to ensure function runtime isolation
When you define an application in Oracle Functions, you specify the subnets in which to run the functions in the application. When functions from different applications are invoked simultaneously, Oracle Functions ensures these function executions are isolated from each other.
Oracle Functions shows applications and their functions in the Console.
References:
https://docs.cloud.oracle.com/en-us/iaas/Content/Functions/Concepts/functionsconcepts.htm

Explanation
Serverless computing refers to a concept in which the user does not need to manage any server infrastructure at all. The user does not run any servers, but instead deploys the application code to a serviceprovider's platform. The application logic is executed, scaled, and billed on demand, without any costs to the user when the application is idle.
Benefits of the Serverless or FaaS
So far almost every aspect of Serverless or FaaS is discussed in a brief, so let's talk about the pros and cons of using Serverless or FaaS Reduced operational and development cost Serverless or FaaS offers less operational and development cost as it encourages to use third-party services like Auth, Database and etc.
Scaling
Horizontal scaling in Serverless or FaaS is completely automatic, elastic and managed by FaaS provider. If your application needs more requests to be processed in parallel the provider will take of that without you providing any additional configuration.
References:
https://medium.com/@avishwakarma/serverless-or-faas-a-deep-dive-e67908ca69d5
https://qvik.com/news/serverless-faas-computing-costs/
https://pages.awscloud.com/rs/112-TZM-766/images/PTNR_gsc-serverless-ebook_Feb-2019.pdf

Explanation
Web Application Firewall (WAF):
Oracle Cloud Infrastructure Web Application Firewall (WAF) is a cloud-based, Payment Card Industry (PCI) compliant, global security service that protects applications from malicious and unwanted internet traffic.
WAF can protect any internet facing endpoint,providing consistent rule enforcement across a customer's applications.
WAF provides you with the ability to create and manage rules for internet threats including Cross-Site Scripting (XSS), SQL Injection and other OWASP-defined vulnerabilities. Unwantedbots can be mitigated while tactically allowed desirable bots to enter. Access rules can limit based on geography or the signature of the request.
The global Security Operations Center (SOC) will continually monitor the internet threat landscape acting asan extension of your IT infrastructure.
References:
https://docs.cloud.oracle.com/en-us/iaas/Content/WAF/Concepts/overview.htm

Explanation
Having created an API gateway and deployed one or more APIs on it, you'll typically want to limit the rate at which front-end clients can make requests to back-end services. For example, to:
- maintain high availability and fair use of resources by protecting back ends from being overwhelmed by too many requests
- prevent denial-of-service attacks
- constrain costs of resource consumption
- restrict usage of APIs by your customers'users in order to monetize APIs You apply a rate limit globally to all routes in an API deployment specification.
If a request is denied because the rate limit has been exceeded, the response header specifies when the request can be retried.
You can add arate-limiting request policy to an API deployment specification by:
using the Console
editing a JSON file
{
"requestPolicies": {
"rateLimiting": {
"rateKey": "CLIENT_IP",
"rateInRequestsPerSecond": 10
}
},
"routes":[
{
"path": "/hello",
"methods": ["GET"],
"backend": {
"type": "ORACLE_FUNCTIONS_BACKEND",
"functionId": "ocid1.fnfunc.oc1.phx.aaaaaaaaab______xmq"
}
}
]
}
https://docs.cloud.oracle.com/en-us/iaas/Content/APIGateway/Tasks/apigatewaylimitingbackendaccess.htm

Explanation
When a function you've deployed to Oracle Functions is running, it can access other Oracle Cloud Infrastructure resources. For example:
- You might want a function to get alist of VCNs from the Networking service.
- You might want a function to read data from an Object Storage bucket, perform some operation on the data, and then write the modified data back to the Object Storage bucket.
To enable a function to access anotherOracle Cloud Infrastructure resource, you have to include the function in a dynamic group, and then create a policy to grant the dynamic group access to that resource.
https://docs.cloud.oracle.com/en-us/iaas/Content/Functions/Tasks/functionsaccessingociresources.htm