Explanation:
Box 1: role-based access control (RBAC)
Azure Storage supports authentication and authorization with Azure AD for the Blob and Queue services via Azure role-based access control (Azure RBAC).
Scenario: File access must restrict access by IP, protocol, and Azure AD rights.
Box 2: change feed
The purpose of the change feed is to provide transaction logs of all the changes that occur to the blobs and the blob metadata in your storage account.
The file updates must be read-only, stored in the order in which they occurred, include only create, update, delete, and copy operations, and be retained for compliance reasons.
Reference:
https://docs.microsoft.com/en-us/azure/cdn/cdn-sas-storage-support
https://docs.microsoft.com/en-us/azure/storage/blobs/storage-blob-change-feed?tabs=azure-portal
Topic 4, Proseware, Inc
Case study
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Background
You are a developer for Proseware, Inc. You are developing an application that applies a set of governance policies for Proseware's internal services, external services, and applications. The application will also provide a shared library for common functionality.
Requirements
Policy service
You develop and deploy a stateful ASP.NET Core 2.1 web application named Policy service to an Azure App Service Web App. The application reacts to events from Azure Event Grid and performs policy actions based on those events.
The application must include the Event Grid Event ID field in all Application Insights telemetry.
Policy service must use Application Insights to automatically scale with the number of policy actions that it is performing.
Policies
Log policy
All Azure App Service Web Apps must write logs to Azure Blob storage. All log files should be saved to a container named logdrop. Logs must remain in the container for 15 days.
Authentication events
Authentication events are used to monitor users signing in and signing out. All authentication events must be processed by Policy service. Sign outs must be processed as quickly as possible.
PolicyLib
You have a shared library named PolicyLib that contains functionality common to all ASP.NET Core web services and applications. The PolicyLib library must:
Exclude non-user actions from Application Insights telemetry.
Provide methods that allow a web service to scale itself.
Ensure that scaling actions do not disrupt application usage.
Other
Anomaly detection service
You have an anomaly detection service that analyzes log information for anomalies. It is implemented as an Azure Machine Learning model. The model is deployed as a web service. If an anomaly is detected, an Azure Function that emails administrators is called by using an HTTP WebHook.
Health monitoring
All web applications and services have health monitoring at the /health service endpoint.
Issues
Policy loss
When you deploy Policy service, policies may not be applied if they were in the process of being applied during the deployment.
Performance issue
When under heavy load, the anomaly detection service undergoes slowdowns and rejects connections.
Notification latency
Users report that anomaly detection emails can sometimes arrive several minutes after an anomaly is detected.
App code
EventGridController.cs
Relevant portions of the app files are shown below. Line numbers are included for reference only and include a two-character prefix that denotes the specific file to which they belong.

LoginEvent.cs
Relevant portions of the app files are shown below. Line numbers are included for reference only and include a two-character prefix that denotes the specific file to which they belong.

A service SAS is secured with the storage account key. A service SAS delegates access to a resource in only one of the Azure Storage services: Blob storage, Queue storage, Table storage, or Azure Files.
Stored access policies give you the option to revoke permissions for a service SAS without having to regenerate the storage account keys.
Reference:
https://docs.microsoft.com/en-us/azure/storage/common/storage-sas-overview

Explanation: