TU Wien:Distributed Systems Technologies VU (Morichetta)/Final Exam 30.6.2021

• Discuss the properties of layering for applications, and describe three use-cases with different layer distribution.
• In the context of Microservices, explain the term "Chatty Interface" and what problems such an interface causes.
• Given the following Map--Reduce functions and input data, write down the individual steps and final results when applying the Map--Reduce query. Describe what is the role and the output of every function, from the intermediate states to the end. INPUT: A collection of structured textual files containing the hourly value of humidity and temperature from a set of sensors located in different areas..
• Explain the term leaky abstraction. Give an example of a leaky abstraction and explain what makes it leaky.
• Describe the two main approaches applicable for a message consumer, defining advantages and disadvantages.
• Briefly explain the term "distributed transaction". Give an example of when it is necessary, and how it can be implemented.
• Briefly explain how you could use Annotations, Dynamic Proxies, and Dependency Injection to implement a container-managed database transaction mechanisms.
• Describe the hardware-based virtualization, what are the possible configurations? What are their differences? Give an example for each configuration.
• Explain the principle of delegated authorization in distributed systems and why it is a fundamental part of modern web applications.
• In the context of event-based architecture, what is "event-carried state transfer"? Name two consequences (e.g., benefits or drawbacks) of using the pattern.
• How does Apache Kafka enable reliability in distributed stream processing systems? (hint: think about a) operator parallelization/distribution and what happens when operator nodes fail, and b) operators that struggle with load peaks
• Describe the three types of autoscaling, and provide an example for every one of them.
• What is the idea behind complex event processing? Make an example with Flink.

Single / Multiple Choice Questions:

• Key characteristics of RESTful services are:
• In the OAuth Authorization Code Grant Flow, an Access Token is
• In Aspect-Oriented Programming, an Advice is
• Which statement about the Data Mapper pattern iscorrect?
• In Remote Procedure Call frameworks, the Skeleton is responsible for:
• Suppose you have to perform a study on autonomous driving systems. This means collecting a considerable amount of data from systems deployed on various car vendors, that share some common information but also have different characteristic. You need to access it, and get information like, e.g., the trip route. What is the apropriate technology for this scenario?
• Which statements about different scheduler architectures are correct?
• What is the task of the scheduler in Kubernetes?
• Which one(s) of the following are black box metrics
• Which statement(s) about watermarking are true?