我最近在学习网络协议，能帮我简要解释一下 TCP/IP 模型吗？要求：回答必须以 HTML 格式输出，内容分层清晰，且必须包含以下四个要点：1. 四层结构，2. 各层的名称和功能，3. 各层之间的关系，4. 实际应用中的重要性。
user
<html>
    <head>
        <title>TCP/IP Model Explanation</title>
    </head>
    <body>
        <h1>TCP/IP Model Overview</h1>
        <h2>1. Four-Layer Structure</h2>
        <p>The TCP/IP model consists of four distinct layers: Application, Transport, Internet, and Network Access.</p>
        
        <h2>2. Names and Functions of Each Layer</h2>
        <ul>
            <li><strong>Application Layer:</strong> Provides end-user services and handles specific application protocols like HTTP, FTP, and SMTP.</li>
            <li><strong>Transport Layer:</strong> Ensures end-to-end communication and data integrity. Protocols include TCP for reliable transmission and UDP for faster, less reliable delivery.</li>
            <li><strong>Internet Layer:</strong> Manages the routing of data packets across networks. It uses the IP protocol to determine the best path for data.</li>
            <li><strong>Network Access Layer:</strong> Deals with the physical transmission of data and includes hardware details like Ethernet and MAC addressing.</li>
        </ul>
        
        <h2>3. Relationship Between Layers</h2>
        <p>Each layer in the TCP/IP model relies on the services provided by the layer below it. The Application layer interacts with the user and prepares the data, which is then passed down through the Transport and Internet layers for routing and transmission, finally reaching the Network Access layer for physical delivery.</p>
        
        <h2>4. Importance in Practical Applications</h2>
        <p>The TCP/IP model is fundamental to the functioning of the modern internet. It enables different types of networks to communicate, supporting various applications from email to streaming video. Its layered approach allows for modularity and easy troubleshooting, making it a cornerstone of internet communication.</p>
    </body>
</html>
assistant