TCP & UDP 2.1

Protocol

A set of rules that define how devices communicate on a network.

Packet

Smaller chunk of data created when a large file is broken down for transmission across a network.

Packet header

Label on a packet that typically includes sender, receiver, and packet order information.

Transmission Control Protocol (TCP)

A protocol that uses a three-way handshake (SYN, SYN-ACK, ACK) to establish a reliable connection, ensuring all packets are delivered in order.

Three-way handshake

The TCP process of establishing a connection: SYN (request), SYN-ACK (response), ACK (confirmation).

TCP/IP protocol suite

A set of related protocols where TCP handles segmentation/sequencing and IP handles addressing and delivery.

User Datagram Protocol (UDP)

A protocol that sends data without ensuring all packets arrive, offering lower latency but less reliability.

UDP use cases

Ideal for applications needing low latency such as video/audio streaming, online gaming, and VoIP.

TCP use cases

Best for situations requiring guaranteed delivery and packet order, such as file transfers and secure communications.

VoIP and UDP

Voice over IP uses UDP; packet loss may cause degraded quality but maintains real-time conversation without delays.

TFTP (Trivial File Transfer Protocol)

a protocol often used for simple, low-overhead file transfers.

Reliability trade-off

TCP provides guaranteed delivery with higher latency; UDP provides faster delivery with potential packet loss.

UDP additional use case

DNS queries are a common application that uses UDP due to low-latency requirements and best-effort delivery.