Before you can connect to on-premises data sources from Azure Logic Apps, download and install the on-premises data gateway on a local computer. The gateway works as a bridge that provides quick data transfer and encryption between data sources on premises (not in the cloud) and your logic apps.
The gateway supports BizTalk Server 2016.
Note: Microsoft have now fully incorporated the Azure BizTalk Services capabilities into Logic Apps and Azure App Service Hybrid Connections.
Logic Apps Enterprise Integration pack bring some of the enterprise B2B capabilities like AS2 and X12, EDI standards support Scenario: The Shipping Logic app must meet the following requirements:
Support the ocean transport and inland transport workflows by using a Logic App.
Support industry-standard protocol X12 message format for various messages including vessel content details and arrival notices.
Secure resources to the corporate VNet and use dedicated storage resources with a fixed costing model.
Maintain on-premises connectivity to support legacy applications and final BizTalk migrations.
Reference:
https://docs.microsoft.com/en-us/azure/logic-apps/logic-apps-gateway-install

Using topic client, call RegisterMessageHandler which is used to receive messages continuously from the entity. It registers a message handler and begins a new thread to receive messages.
This handler is waited on every time a new message is received by the receiver.
subscriptionClient.RegisterMessageHandler(ReceiveMessagesAsync, messageHandlerOptions); Reference:
https://www.c-sharpcorner.com/article/azure-service-bus-topic-and-subscription-pub-sub/

Explanation

Box 1: user_impersonation
Box 2: delegated
Example:
1.Select the API permissions section
2.Click the Add a permission button and then:
Ensure that the My APIs tab is selected
3.In the list of APIs, select the API TodoListService-aspnetcore.
4.In the Delegated permissions section, ensure that the right permissions are checked: user_impersonation.
5.Select the Add permissions button.
Box 3: delegated
Example
1.Select the API permissions section
2.Click the Add a permission button and then,
Ensure that the Microsoft APIs tab is selected
3.In the Commonly used Microsoft APIs section, click on Microsoft Graph
4.In the Delegated permissions section, ensure that the right permissions are checked: User.Read. Use the search box if necessary.
5.Select the Add permissions button
References:
https://docs.microsoft.com/en-us/samples/azure-samples/active-directory-dotnet-webapp-webapi-openidconnect-

A: Revoke a user delegation SAS
To revoke a user delegation SAS from the Azure CLI, call the az storage account revoke-delegation-keys command. This command revokes all of the user delegation keys associated with the specified storage account. Any shared access signatures associated with those keys are invalidated.
B: To revoke a stored access policy, you can either delete it, or rename it by changing the signed identifier.
Changing the signed identifier breaks the associations between any existing signatures and the stored access policy. Deleting or renaming the stored access policy immediately effects all of the shared access signatures associated with it.
D18912E1457D5D1DDCBD40AB3BF70D5D
Reference:
https://github.com/MicrosoftDocs/azure-docs/blob/master/articles/storage/blobs/storage-blob-user-delegationsas-create-cli.md
https://docs.microsoft.com/en-us/rest/api/storageservices/define-stored-access-policy#modifying-or-revoking-astored-access-policy

Explanation:
Box 1: If WEBSITES_ENABLE_APP_SERVICE_STORAGE
If WEBSITES_ENABLE_APP_SERVICE_STORAGE setting is unspecified or set to true, the /home/ directory will be shared across scale instances, and files written will persist across restarts Box 2: /home Reference:
https://docs.microsoft.com/en-us/azure/app-service/containers/app-service-linux-faq