Past Exams

DS Exam WS 2014/15

Models + Architecture of DS

• Name 2 reasons justifying use of DS
• Explain purpose of tiers in 3 tier architecture
• 2 reasons use services over (instead) objects and components

Communication

• Name more than 3 features of RPC
• Task of stubs in RPC communication
• Principle of communication using message channel

Basic Services for DS

• Describe message exchange for error free communication according to 2 phase commit protocol
• Explain creation + validation of digital signature
• Why need trust center / certificate authority for management of public keys with asym. cryptographic algorithms

Component based DS

• Purpose of EJB local/remote interfaces. Differences?
• Name more than 2 differences EJB <-> OSGi component models
• Lamport Approch with P1, P2, P3

Business Processes + Web Services

• Petri net specification for parallel execution of 3 activities, followed by alternative execution of 2 activities within workflow
• What is specified in standards: WS Coordination, WS-AtomicTransaction, WS-BusinessActivity
• Explain concept of Enterprise Service Bus

If somethings not right or I forgot something please feel free the comment!