---
title: "Short note: Client-Server and Master-Slave"
subject: "Big Data Technologies"
chapter: 1
key: "semester_8/big_data_technologies:short-note-client-server-master-slave"
source: https://www.bctengineer.com/q/semester_8/big_data_technologies/short-note-client-server-master-slave
site: BCT Engineering
---

# Short note: Client-Server and Master-Slave

Big Data Technologies · Chapter 1: Introduction to Big Data

- Asked in: 2075 Bhadra, 5 marks
- Video: [Master slave Architecture Pattern](https://www.youtube.com/watch?v=rtBjcfwBLYk) — Dr. Muhammad Yaseen
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_8/big_data_technologies/short-note-client-server-master-slave
- Whole chapter: https://www.bctengineer.com/md/semester_8/big_data_technologies/chapter-1

## Question

Write a short note on Client-Server and Master-Slave architecture.

## Short answer

In client-server architecture, clients request services from a server that processes and responds; e.g., web browser and web server. Master-slave architecture has a master node that controls and delegates tasks to multiple slave nodes that perform the work, like HDFS NameNode and DataNodes.

## Answer

#### Client-Server architecture
A model in which **clients** request services and **servers** provide them over a network. The server is a powerful machine that waits for requests, processes them and returns responses. Clients start the communication.

```text
 +--------+  request   +--------+   +----------+
 | Client |----------->| Server |-->| Database |
 | (PC)   |<-----------| (host) |<--|          |
 +--------+  response  +--------+   +----------+
```
- Examples: web browser and web server, e-mail, database client and DBMS.
- Advantages: central control of data and security, easy maintenance and update.
- Disadvantages: server is a single point of failure and a bottleneck under heavy load.

#### Master-Slave architecture
One node, the **master**, controls and coordinates the work, and many **slave (worker)** nodes carry out the tasks assigned by the master. The master holds metadata, assigns tasks and monitors the slaves; slaves store data and compute.

```text
          +--------+
          | Master |
          +---+----+
        +-----+-----+
     +--v--+ +--v--+ +--v--+
     |Slave| |Slave| |Slave|
     +-----+ +-----+ +-----+
```
- Examples: GFS (master and chunk servers), HDFS (NameNode and DataNodes), MapReduce (JobTracker and TaskTrackers), MySQL replication.
- Advantages: simple coordination and consistency, good for parallel work.
- Disadvantages: master is a single point of failure (solved with standby or shadow masters) and can become a bottleneck.

#### Difference
In client-server, the relation is request/response between different roles of service user and provider. In master-slave, the master actively controls and delegates tasks to slaves that work for it.

## Check yourself

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

1. In client-server architecture, who starts the communication?
   A. The server, which pushes tasks
   B. The database
   C. The clients, which request services from the server
   D. A master node
   Answer: C. Clients start communication by sending requests; the server waits, processes and responds. (Key point: Client-server communication)

2. What does the master do in master-slave architecture?
   A. Controls and coordinates, holds metadata, assigns tasks and monitors slaves
   B. Only stores data blocks
   C. Only requests services
   D. Does nothing after start-up
   Answer: A. The master coordinates the work while slaves store data and compute. (Key point: Master-slave role)

3. What common disadvantage do both architectures share, and how is it handled in master-slave?
   A. Slow disks; solved by RAID
   B. The server/master is a single point of failure and bottleneck; standby or shadow masters help
   C. Too many masters; solved by removing slaves
   D. No coordination; solved by clients
   Answer: B. The central server or master can fail or become a bottleneck; master-slave uses standby or shadow masters. (Key point: Single point of failure)

## Related in Big Data Technologies

- [GFS master role in read/write](https://www.bctengineer.com/question.md?key=semester_8%2Fbig_data_technologies%3Agfs-master-read-write-flow) — Big Data Technologies, chapter 2

## Related in other subjects

- [Client/server architecture and FTP operation](https://www.bctengineer.com/question.md?key=semester_8%2Finternet_and_intranet%3Aclient-server-ftp) — Internet and Intranet, chapter 3
- [Features of client/server architecture](https://www.bctengineer.com/question.md?key=semester_7%2Fcomputer_networks_and_security%3Aclient-server-features) — Computer Networks and Security, chapter 1
- [Architecture before specification; client-server](https://www.bctengineer.com/question.md?key=semester_5%2Fsoftware_engineering%3Aarchitecture-before-specification) — Software Engineering, chapter 3
- [Client-server versus distributed object architecture](https://www.bctengineer.com/question.md?key=semester_5%2Fsoftware_engineering%3Aclient-server-vs-distributed-object) — Software Engineering, chapter 3