Interprocess Communication (IPC): Types, Mechanisms, Examples

Modern computer systems run many processes at the same time. Whether it is a desktop operating system, a cloud server, a mobile phone, or an embedded system—multiple processes often need to exchange data, coordinate actions, or share resources. This communication between processes is known as Interprocess Communication (IPC).

IPC is a critical concept in operating systems, networks, distributed computing, cloud systems, and even microservices architecture. Understanding IPC helps programmers design reliable software, prevents race conditions, improves performance, and ensures smooth multi-tasking.

✔ What is IPC?
✔ Why IPC is needed
✔ Types of IPC
✔ IPC mechanisms
✔ Advantages & challenges
✔ Real-world applications
✔ Differences between IPC & RPC
✔ Security issues
✔ Modern IPC in Linux, Windows & Android

Let’s begin.

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 What is Interprocess Communication (IPC)? — Simple Definition

Interprocess Communication (IPC) refers to the methods that allow processes (running programs) to exchange data and coordinate their actions.

In simple words:

👉 IPC allows one process to talk to another process.

It helps processes:

• Share information

• Send messages

• Synchronize tasks

• Avoid conflicts

• Increase efficiency

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⭐ Why Do We Need Interprocess Communication?

Modern systems rely on multiple processes working together.

📌 Reasons IPC is necessary:

1. Data Sharing

Processes need to exchange data to complete tasks.

Example:
A browser process shares data with a rendering engine and network process.

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2. Resource Sharing

Multiple processes may need access to:

• Printers

• Disk drives

• Databases

• Shared memory

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3. Computation Speed

Distributed or parallel programs break tasks into multiple processes.

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4. Synchronization

Processes must coordinate to prevent errors such as:

• Race conditions

• Deadlocks

• Inconsistent data updates

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5. Modularity

Complex systems are broken into smaller processes.

Example:
In Linux, many services run as independent daemons but communicate via IPC.

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6. Real-Time Operations

Robotics, embedded systems, and microcontrollers require coordinated process communication.

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Without IPC, multitasking and multiprocessing would be impossible.

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⭐ How Processes Communicate (Basic Overview)

Communication happens in two ways:

1. Shared Memory

Processes access a common memory space.

2. Message Passing

Processes send and receive messages through the OS.

Both methods have advantages and are used in different scenarios. We will explore each in detail.

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⭐ Types of Interprocess Communication (IPC)

IPC methods fall into two major categories:

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🟦 1. Shared Memory IPC

Shared Memory allows two or more processes to access the same memory segment.

✔ Fastest IPC method

✔ No need for kernel intervention

✔ Best for large data transfer

However, it requires synchronization mechanisms like:

• Semaphores

• Mutex locks

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🟧 2. Message Passing IPC

Processes send/receive messages with the help of the operating system.

✔ Safe

✔ Organized

✔ Good for distributed systems

Message passing is further divided into:

• Direct communication

• Indirect communication

• Synchronous

• Asynchronous

• Buffered

• Unbuffered

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⭐ IPC Mechanisms (Detailed)

Operating systems support several IPC techniques. Below are the most important ones.

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1. Pipes

Pipes are the simplest IPC mechanism.

✔ Unidirectional (one-way communication)

✔ Used between parent-child processes

✔ Works like a physical pipeline for data

Example in Linux:

command1 | command2

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2. Named Pipes (FIFOs)

Unlike regular pipes, named pipes:

• Have a specific name

• Support communication between unrelated processes

Example:

mkfifo mypipe

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3. Message Queues

Message queues allow structured messages to be stored in a queue.

✔ Asynchronous communication

✔ Sender and receiver do not need to be active at the same time

Used in:

• Banking systems

• Operating system kernels

• Distributed apps

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4. Shared Memory

This is the fastest and most efficient IPC technique.

✔ Multiple processes share the same memory segment

✔ Extremely fast for large data

✔ Requires synchronization tools

Example:

shmget(), shmat(), shmdt()

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5. Semaphores

Semaphores control access to shared resources.

✔ Prevent race conditions

✔ Ensure mutual exclusion (mutex)

Used widely in:

• Operating systems

• Databases

• High-concurrency systems

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6. Sockets

Sockets allow communication between:

• Processes on the same system

• Processes on remote systems

✔ Used in networking

✔ Base of TCP/IP communication

✔ Used in client–server applications

Example:
Web browsers communicate with servers using sockets.

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7. Signals

Signals notify processes of events.

Example:

• Ctrl+C sends SIGINT

• Child process termination sends SIGCHLD

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8. RPC (Remote Procedure Call)

RPC allows a program to call a function on another system.

✔ Fundamental to distributed computing

✔ Used in microservices

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⭐ IPC in Modern Operating Systems (2025)

Different operating systems implement IPC in different ways.

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IPC in Linux

Linux supports:

• Pipes & FIFOs

• System V message queues

• POSIX shared memory

• Semaphores

• Signals

• Unix domain sockets

Linux servers heavily rely on IPC for background services (daemons).

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IPC in Windows

Windows supports:

• Named pipes

• Memory-mapped files

• Mail slots

• Windows Sockets (WinSock)

• RPC

• COM / DCOM

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IPC in Android

Android applications use IPC through:

• Binder

• AIDL (Android Interface Definition Language)

• Intents

• Broadcast receivers

Android’s Binder IPC is one of the fastest IPC mechanisms ever built.

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 Advantages of Interprocess Communication

✔ Faster processing

✔ Better modularity

✔ Enables multitasking

✔ Increases system efficiency

✔ Supports distributed computing

✔ Simplifies large system design

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 Challenges in IPC

Despite advantages, IPC also has challenges.

❌ Race conditions

❌ Deadlocks

❌ Concurrency issues

❌ Message loss

❌ Security vulnerabilities

❌ Complexity in synchronization

❌ Memory access errors (in shared memory)

Correct design and testing are crucial for stable IPC.

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Real-World Examples of IPC

IPC is everywhere—even if users don’t see it.

✔ Browser communicating with renderer

✔ Printer driver communicating with OS

✔ WhatsApp notifications communicating with OS

✔ ATM withdrawal transaction systems

✔ Distributed microservices

✔ SQL database engine using processes

✔ Robotics & IoT devices

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⭐ IPC vs RPC (Important Difference)

Feature	IPC	RPC
Meaning	Local communication	Remote communication
Speed	Very fast	Slower
Used for	OS-level processes	Network-level apps
Interaction	Message-based	Function-based

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 Synchronization in IPC

Synchronization prevents conflicts.

Important tools:

• Mutex

• Semaphore

• Monitors

• Condition variables

• Atomic operations

These prevent multiple processes from modifying data at the same time.

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 IPC in Cloud and Distributed Systems 

Cloud systems use IPC mechanisms such as:

• Message brokers (Kafka, RabbitMQ)

• REST APIs

• gRPC

• Pub/Sub systems

• Event-driven architecture

Processes often run on different servers across the world.

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 Security in IPC

IPC must be secure to avoid:

• Unauthorized access

• Data leaks

• Injection attacks

Measures include:
✔ Access control
✔ Authentication
✔ Encryption
✔ Sandboxing

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⭐ Conclusion

Interposes Communication (IPC) is a fundamental concept of modern computing. It enables independent processes to exchange data, coordinate actions, share resources, and work efficiently. From Linux servers to Android apps, from cloud systems to embedded devices—IPC is everywhere.

✔ What IPC is
✔ Why it is needed
✔ Types of IPC
✔ Mechanisms like pipes, shared memory, message queues, semaphores, sockets
✔ IPC in Linux, Windows, Android
✔ Advantages and challenges
✔ Real-world uses
✔ Future trends

For students, IT professionals, and developers, mastering IPC is essential for understanding operating systems, networks, distributed computing, microservices, and system programming.