Dictionary · Networking Fundamentals
TCP
TCP — Transmission Control Protocol
Transport · Beginner
A transport protocol that creates a reliable, ordered byte stream between applications. It numbers data, retransmits losses, and uses a handshake before the stream begins.
Applications choose this when they need a complete conversation in the original order. Web pages, mail submission, and file transfers commonly rely on it.
Picture it
Both sides agree on starting numbers before application data flows. A simple datagram lookup does not use this exchange.
Example: A browser opens a reliable connection to port 443 and can detect when a segment must be sent again.
Common misconception
- Reliability here means recovering lost segments, not proving the application or the organization is trustworthy.