Distributed Systems Code:  22.624    :  6
View general information   Description   Information prior to enrolment   Learning objectives and results   Content   View the UOC learning resources used in the subject   Guidelines on assessment at the UOC   View the assessment model  
This is the course plan for the second semester of the academic year 2022/2023. To check whether the course is being run this semester, go to the Virtual Campus section More UOC / The University / Programmes of study section on Campus. Once teaching starts, you'll be able to find it in the classroom. The course plan may be subject to change.
This subject focuses on knowing the main concepts related to distributed systems and applications at Internet scale. Distributed applications are systems formed by some, several or many computers interconnected thorough a network and with processes that interact with each other in a complex way, sharing resources and services.


Networks and Internet Applications , Operating systems and object-oriented programming (practical assignments are done in Java)


The main objective is to know the organization of distributed systems, their issues and the main algorithms and mechanisms that are used to address them, as well as examples of popular distributed applications.

The general objectives are summarized in:
  • To  know the models of organization of blocks of a distributed system or application and the relationship between them.
  • To understand the difficulties and advantages that can be obtained from exploiting the "apparent" weaknesses of the distribution
  • To know the fundamental aspects and algorithms on aspects such as time, coordination, consensus and replication in distributed systems
  • To know the main aspects of some popular distributed applications


Module 1. Introduction and general concepts
1.1. Characterization of distributed systems
1.2. System models.

Module 2. Fundamentals of distributed systems
2.1. Global time and state
2.2. Coordination and consensus
2.3. Transactions and concurrence control
2.4. Transactions Distributed
2.5. Replication
2.6. Safety

Module 3. Middleware and use cases
3.1. Indirect communication
3.2. Peer systems
3.3. Distributed systems design: Google's case study


The assessment process is based on the student's personal work and presupposes authenticity of authorship and originality of the exercises completed.

Lack of authenticity of authorship or originality of assessment tests, copying or plagiarism, the fraudulent attempt to obtain a better academic result, collusion to copy or concealing or abetting copying, use of unauthorized material or devices during assessment, inter alia, are offences that may lead to serious academic or other sanctions.

Firstly, you will fail the course (D/0) if you commit any of these offences when completing activities defined as assessable in the course plan, including the final tests. Offences considered to be misconduct include, among others, the use of unauthorized material or devices during the tests, such as social media or internet search engines, or the copying of text from external sources (internet, class notes, books, articles, other students' essays or tests, etc.) without including the corresponding reference.

And secondly, the UOC's academic regulations state that any misconduct during assessment, in addition to leading to the student failing the course, may also lead to disciplinary procedures and sanctions.

The UOC reserves the right to request that students identify themselves and/or provide evidence of the authorship of their work, throughout the assessment process, and by the means the UOC specifies (synchronous or asynchronous). For this purpose, the UOC may require students to use a microphone, webcam or other devices during the assessment process, and to make sure that they are working correctly.

The checking of students' knowledge to verify authorship of their work will under no circumstances constitute a second assessment.


This course can only be passed through continuous assessment (CA), the mark for which is combined with a practical (Pr) mark to give the final course mark. It is not planned to have any final test.The formula for accrediting the course is as follows: CA + Pr.