A protocol stack is a layered collection of communication protocols that work together to enable data exchange between devices in a network. Each layer in the stack has a specific function and relies on the layers below it to provide services, creating a structured approach to network communication.
A protocol stack can handle:
- Arbitrary Message Sizes → Packet Switched Network
- Out of order delivery → Sequence Number
- Packet Loss → ACK and buffers
- Bit Errors → Checksum
- Queueing delays
OSI Model is a protocol stack.