Why does Youtube use TCP not UDP?




Why does Youtube use TCP not UDP?

TCP stands for Transmission Control Protocol, which is one of the core protocols of the Internet protocol suite. It provides reliable, ordered, and error-checked delivery of data between applications running on hosts communicating over IP networks.

TCP operates at the transport layer of the OSI model, which is responsible for ensuring that data is transmitted reliably and efficiently across a network. TCP breaks data into packets, numbers and sequences them, sends them across the network, and then verifies their arrival at the destination.

TCP uses a three-way handshake to establish a connection between two devices: SYN (synchronize), SYN-ACK (synchronize-acknowledge), and ACK (acknowledge). This process ensures that both devices agree on the terms of the connection before data is exchanged.

TCP is widely used for applications that require reliable, ordered delivery of data, such as email, file transfer, and web browsing.

UDP stands for User Datagram Protocol. It is a transport layer protocol that operates on top of IP (Internet Protocol) in computer networks. Unlike TCP (Transmission Control Protocol), UDP is a connectionless protocol, which means that it does not establish a dedicated end-to-end connection between two communicating applications.

UDP is primarily used for applications that require fast transmission of data but are tolerant of packet loss, such as online gaming, video streaming, and voice over IP (VoIP) services. UDP provides a minimalistic and lightweight mechanism for sending datagrams (packets) of data from one host to another. It does not provide any reliability, flow control, or congestion avoidance mechanisms, which makes it faster and more efficient than TCP but also less reliable.

UDP packets contain only basic header information, including the source and destination ports and the length of the packet. UDP does not use sequence numbers, acknowledgments, or retransmission of lost packets, which can result in lost, duplicated, or out-of-order packets. Applications that use UDP are responsible for implementing their own error detection, correction, and flow control mechanisms, if needed.

Why does Youtube use TCP not UDP

YouTube primarily uses TCP (Transmission Control Protocol) instead of UDP (User Datagram Protocol) because TCP is a reliable and connection-oriented protocol that ensures the delivery of data packets between the client and server.

With TCP, there is a guaranteed delivery of packets as the protocol ensures that every packet sent by the client is received and acknowledged by the server. This is important for video streaming services like YouTube, where the delivery of packets in the correct sequence is essential for the proper playback of the video.

In contrast, UDP is a connectionless protocol that doesn't guarantee the delivery of packets. While UDP is faster than TCP as it does not have the overhead of ensuring the delivery of packets, it is not suitable for video streaming applications like YouTube, where data loss and out-of-order delivery can severely impact the quality of the video.

Therefore, YouTube uses TCP to ensure a reliable and consistent video streaming experience for its users.

TCP is a transport protocol that operates on top of the Internet Protocol (IP) and provides a reliable, ordered, and error-checked delivery of data between applications running on hosts communicating over a network. TCP achieves reliability by using techniques such as flow control, congestion control, and retransmission of lost packets.

In the context of video streaming, TCP provides a stable and consistent data transfer rate, which is crucial for ensuring smooth video playback. TCP's flow control and congestion control mechanisms prevent network congestion, which can cause delays and buffering in the video stream. TCP also uses retransmission of lost packets to ensure that every packet of the video stream is received in the correct order, which is necessary for seamless playback of the video.

On the other hand, UDP is a connectionless protocol that does not guarantee the delivery of packets, nor does it provide any flow or congestion control mechanisms. While UDP is faster than TCP, it is not suitable for applications that require reliability, such as video streaming. UDP is commonly used in applications where a slight loss of data is acceptable, such as online gaming or real-time video conferencing.

In summary, TCP is the preferred protocol for video streaming services like YouTube because it ensures a reliable and consistent data transfer rate, preventing buffering and delays in video playback. UDP, on the other hand, is not reliable but is faster, making it more suitable for applications where speed is more important than reliability.