Anonymous mode is the configuration we have used so far throughout the book.
Anonymous functions do not require any authentication to be accessed. Anyone with access to the function URL can execute the call. For a public PaaS service, this means that anyone on the internet could access the function. For a private ASE this means anyone inside the private network perimeter.
There is certainly use for publicly accessible functions, although in most use cases, the serverless compute would not be directly exposed to the application user (since FaaS is more likely to handle the logic tier of the application rather than the presentation tier). Unless the function public exposure is intentional, some type of authentication or authorization ...
