---
title: "Challenges of DS with example"
subject: "Distributed System"
chapter: 1
key: "semester_7/distributed_system:ds-challenges-example"
source: https://www.bctengineer.com/q/semester_7/distributed_system/ds-challenges-example
site: BCT Engineering
---

# Challenges of DS with example

Distributed System · Chapter 1: Introduction

- Asked in: Model question
- Video: [Distributed Systems Design Introduction (Concepts & Challenges)](https://www.youtube.com/watch?v=Sa_gJwB55jY) — A Dev' Story
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_7/distributed_system/ds-challenges-example
- Whole chapter: https://www.bctengineer.com/md/semester_7/distributed_system/chapter-1

## Question

Why are there challenges in achieving some requirements of a distributed system? Explain the challenges associated with different requirements of distributed system.

## Short answer

Distributed components have no shared memory or clock, communicate by messages that may be delayed or lost, fail independently, and are heterogeneous. This makes transparency, openness, security, scalability, failure handling, concurrency, and quality of service harder than in a single computer, causing partial failures, bottlenecks, and network delays.

## Answer

#### Why challenges arise
A distributed system gets its benefits (sharing, scalability, reliability) from many independent computers joined by a network. But these have no shared memory or clock, communicate by messages that can be delayed or lost, fail independently, and differ in hardware and software. Therefore requirements such as transparency, openness or fault tolerance cannot be achieved as easily as in a single computer.

#### Challenges for different requirements
| Requirement | Challenge | Example |
|---|---|---|
| Heterogeneity | Different networks, OS, hardware, languages and data formats | Windows client with Linux server; solved by middleware, XDR |
| Openness | Published, standard and extensible interfaces | Web services described by WSDL / IDL |
| Security | Open networks; attacks on confidentiality, integrity, availability | Banking requires TLS, authentication |
| Scalability | Bottlenecks in servers, tables and algorithms; physical limits | DNS uses hierarchy and caching to scale |
| Failure handling | Partial and independent failure; cannot tell slow from failed | Replicated servers, retries, checkpoints |
| Concurrency | Shared data used by many clients | Seat booking with locks / transactions |
| Transparency | Delay and failure cannot be fully hidden | Remote call is slower than local |
| Quality of service | Timeliness and reliability on shared networks | Video streaming needs bounded jitter |

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. Why are requirements harder to achieve than on a single computer?
   A. There is no shared memory or clock, messages can be delayed or lost, and components fail independently
   B. Because all components share one memory
   C. Because networks never fail
   D. Because all hardware is identical
   Answer: A. These features of distribution make requirements like transparency and fault tolerance difficult. (Key point: Why challenges arise)

2. How does DNS achieve scalability?
   A. By using one central table
   B. By using a hierarchy and caching
   C. By avoiding any names
   D. By using one server for the world
   Answer: B. Hierarchy and caching avoid a central bottleneck. (Key point: Scalability example)

3. What is used to handle concurrent access, e.g. seat booking?
   A. Locks or transactions
   B. Removing the shared data
   C. Ignoring simultaneous requests
   D. Using different clocks
   Answer: A. Locks and transactions keep shared data consistent. (Key point: Concurrency)

## Related in Distributed System

- [Define DS and its requirements](https://www.bctengineer.com/question.md?key=semester_7%2Fdistributed_system%3Adefine-ds-requirements) — Distributed System, chapter 1, asked 3×
- [Goals and design challenges of DS](https://www.bctengineer.com/question.md?key=semester_7%2Fdistributed_system%3Ads-goals-challenges) — Distributed System, chapter 1, asked 3×
- [DS as a single coherent system](https://www.bctengineer.com/question.md?key=semester_7%2Fdistributed_system%3Asingle-coherent-system) — Distributed System, chapter 1, asked 2×
- [Goals, need of transparency, challenges](https://www.bctengineer.com/question.md?key=semester_7%2Fdistributed_system%3Agoals-transparency-challenges) — Distributed System, chapter 1
- [Transparency: importance and challenges](https://www.bctengineer.com/question.md?key=semester_7%2Fdistributed_system%3Atransparency-importance-challenges) — Distributed System, chapter 1
- [Autonomous vs distributed system](https://www.bctengineer.com/question.md?key=semester_7%2Fdistributed_system%3Aautonomous-vs-distributed) — Distributed System, chapter 1

## Related in other subjects

- [Challenges of modeling a physical system](https://www.bctengineer.com/question.md?key=semester_6%2Fembedded_system%3Amodeling-physical-system-challenges) — Embedded System, chapter 7
- [Distributed system in big data example](https://www.bctengineer.com/question.md?key=semester_8%2Fbig_data_technologies%3Adistributed-system-example) — Big Data Technologies, chapter 1
- [Short note: Distributed system implementation](https://www.bctengineer.com/question.md?key=semester_6%2Fobject_oriented_analysis_and_design%3Ashort-note-distributed-implementation-issues) — Object Oriented Analysis and Design, chapter 4
- [Distributed system and Hadoop](https://www.bctengineer.com/question.md?key=semester_8%2Finformation_system%3Adistributed-system-hadoop-voluminous-data) — Information System, chapter 8