There are five layers present in the Internet protocol stack (TCP/IP model).
The TCP/IP model is a conceptual framework that standardizes how different network devices communicate over the internet. It organizes the communication process into five distinct layers, each with specific responsibilities. Understanding these layers is crucial for network troubleshooting, design, and security.
Here's a breakdown of the five layers:
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Application Layer: This is the layer closest to the end-user. It provides the network interface for applications like web browsers, email clients, and file transfer programs. Examples of protocols used at this layer include HTTP, SMTP, FTP, and DNS.
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Transport Layer: This layer provides reliable and ordered delivery of data between applications. The two main protocols used here are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol). TCP guarantees reliable delivery with error checking and retransmission, while UDP is faster but doesn't guarantee delivery.
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Network Layer (Internet Layer): This layer is responsible for routing data packets across networks. The primary protocol used here is IP (Internet Protocol). IP addresses are used to identify devices on the network, and routing protocols determine the best path for data to travel.
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Data Link Layer: This layer provides error-free transmission of data between two directly connected nodes. It is concerned with framing data, physical addressing (MAC addresses), and error detection. Examples of protocols include Ethernet and Wi-Fi.
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Physical Layer: This is the lowest layer and deals with the physical transmission of data over a communication channel. It defines the physical characteristics of the network, such as voltages, data rates, and cabling.
Therefore, the TCP/IP model utilizes a five-layer architecture to facilitate internet communication.
