Description: Layer 4, also known as the transport layer in the OSI (Open Systems Interconnection) model, is fundamental for end-to-end communication in computer networks. Its main responsibility is to ensure the reliable delivery of data between applications running on different devices. This layer is responsible for segmenting data into packets, controlling the flow of information, and managing error correction. It uses protocols such as TCP (Transmission Control Protocol) and UDP (User Datagram Protocol), each with distinct characteristics: TCP provides a connection-oriented service and guarantees data delivery, while UDP offers a connectionless service, ideal for applications that require speed over reliability, such as video streaming. Layer 4 also plays a crucial role in managing network congestion, ensuring that traffic is handled efficiently. In the context of network architecture, Layer 4 allows for greater flexibility and control over network traffic, facilitating the implementation of security policies and performance optimization. Its relevance extends to protection against DDoS (Distributed Denial of Service) attacks, where the ability to manage traffic and prioritize certain types of data becomes an essential tool for mitigating these attacks and maintaining service availability.
