Network Services

🌐 Network Services

🔧 1. Common Network Services

• Services are provided using a client-server model.
• A client device (e.g., web browser) requests resources from a server (e.g., web server).
• Devices can be on different networks (e.g., accessing a website over the Internet).

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📡 2. Network Protocols

Protocols define how devices communicate. The most important ones are part of the TCP/IP suite:

• TCP: Reliable data delivery.
• IP: Routes packets across networks.
• Together, they allow devices to identify each other and send data correctly.

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🌍 3. Web Services

• HTTP: Used for standard webpage transfers.
• HTTPS: Adds encryption using SSL or TLS for secure browsing.
• Web server software: Apache, Nginx (open-source); IIS (Windows-based).

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📧 4. Email Services

• SMTP: Sends email from sender to mail servers.
• POP3: Downloads email and deletes it from server.
• IMAP4: Keeps email on server for multi-device access.
• Encryption via SSL/TLS ensures secure transmission.

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🌐 5. DNS (Domain Name System)

• Resolves domain names (like [www.example.com]) into IP addresses.
• Critical for accessing websites and services by name instead of numeric IPs.

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🗃️ 6. Database Services

• DBMS allows data storage, access, and management.
• SQL is the primary language used for interacting with databases.
• Examples: Microsoft SQL Server, Oracle, MySQL (open source).

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🔁 7. File Transfer Services

• FTP: Used for transferring files but lacks security.
• FTPS: FTP secured with SSL/TLS.
• SFTP: Secure transfer based on SSH, preferred for modern use.

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🖥️ 8. Remote Access Services

• Allow control of remote computers.
• Telnet: Insecure and outdated.
• SSH: Secure, encrypted command-line access.
• RDP: Graphical remote access on Windows.

🔐 Remote access must be secured to avoid unauthorized entry.

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