Explanation:

Box 1: Service principal
Applications and container orchestrators can perform unattended, or "headless," authentication by using an Azure Active Directory (Azure AD) service principal.
Box 2: AcrPush
AcrPush provides pull/push permissions only and meets the principle of least privilege.
Reference:
https://docs.microsoft.com/en-us/azure/container-registry/container-registry-authentication?tabs=azure-cli
https://docs.microsoft.com/en-us/azure/container-registry/container-registry-roles?tabs=azure-cli

Explanation:

Claims in access tokens
JWTs (JSON Web Tokens) are split into three pieces:
* Header - Provides information about how to validate the token including information about the type of token and how it was signed.
* Payload - Contains all of the important data about the user or app that is attempting to call your service.
* Signature - Is the raw material used to validate the token.
Your client can get an access token from either the v1.0 endpoint or the v2.0 endpoint using a variety of protocols.
Scenario: User authentication (see step 5 below)
The following steps detail the user authentication process:
* The user selects Sign in in the website.
* The browser redirects the user to the Azure Active Directory (Azure AD) sign in page.
* The user signs in.
* Azure AD redirects the user's session back to the web application. The URL includes an access token.
* The web application calls an API and includes the access token in the authentication header. The application ID is sent as the audience ('aud') claim in the access token.
* The back-end API validates the access token.
Reference:
https://docs.microsoft.com/en-us/azure/api-management/api-management-access-restriction-policies

Explanation:

Step 1: az batch pool create
# Create a new Linux pool with a virtual machine configuration.
az batch pool create \
--id mypool \
--vm-size Standard_A1 \
--target-dedicated 2 \
--image canonical:ubuntuserver:16.04-LTS \
--node-agent-sku-id "batch.node.ubuntu 16.04"
Step 2: az batch job create
# Create a new job to encapsulate the tasks that are added.
az batch job create \
--id myjob \
--pool-id mypool
Step 3: az batch task create
# Add tasks to the job. Here the task is a basic shell command.
az batch task create \
--job-id myjob \
--task-id task1 \
--command-line "/bin/bash -c 'printenv AZ_BATCH_TASK_WORKING_DIR'"
Step 4: for i in {1..$numberOfJobs} do
References:
https://docs.microsoft.com/bs-latn-ba/azure/batch/scripts/batch-cli-sample-run-job