Internet Security: A Hands-on Approach (Udemy.com)

This is an incredibly well‑structured and practical network security course, offering real hands‑on value for learners of different backgrounds. It systematically walks through how the Internet works and dives deep into critical security topics: attacks targeting ARP, TCP/IP, DNS and BGP protocols, sniffing and spoofing techniques, alongside firewalls and VPN security mechanisms. Professor Du simplifies complicated protocol and security concepts with clear, logical explanations. He strikes a great balance between theory and real‑world attack scenarios. Instead of only teaching abstract textbook knowledge, he shows exactly how common network exploits happen and what practical countermeasures we can use. Each module is neatly organized, building knowledge step‑by‑step without overwhelming audiences. What impresses me most is its strong practical orientation. It closes the gap between basic networking theory and real‑life cybersecurity threats, helping you develop a solid security mindset and grasp core attack‑defense skills. Whether you are a cybersecurity beginner, IT worker or student wanting to strengthen your network security foundation, this course is well worth your time. Highly recommended.

Finally, a security course that doesn't skip the "why" I enrolled with essentially zero networking background — whatever I learned 20 years ago is long gone. Professor Wenliang Du (ACM/IEEE Fellow, Syracuse) has 20+ years teaching this material, and it shows in how deliberately he paces the fundamentals. He doesn't just recite protocol specs; he explains why TCP/IP, ARP, DNS, etc. were designed the way they were, which made the attack vectors that follow actually click for me. The SEED Labs are the real differentiator. Having labs used by 1100+ universities baked directly into a Udemy course is unusual — you go from lecture to actually implementing sniffers, spoofing, firewall/ VPN basics in C/Python inside a contained VM. It is challenging (the VM setup can be a bit fiddly across versions, fair warning), but it's the kind of challenge that sticks. If you want to understand internet security instead of just memorising tool names, this is the one.

This course is indeed excellent. I would only suggest to emphasize that, when talking about NAT, the most typical case of NAT used in most homes does a mapping from a private IP and source port of a connection to public IP and another port in the NAT machine (the modem-router in the home scenario) rather than just a direct mapping from private IP to public IP, allowing many private IPs to map to the same public IP.

I wanted a refund but this institution would not allow me for the reason that i have covered more than enough to qualify for refund. This is too difficult in my case. I wasted money again.

This course provides low-level knowledge in cyber security and many kinds of attacks. The instructor explains how these attacks work behind the scenes and also highlights the fact that pupils have the knowledge to create their own tools.

Really fantastic course. It was a really unique and fulfilling experience to experiment with cyberattacks and learn about the OSI network model in a virtual, hands-on environment. I also learned Linux through the course. Really appreciate the Professor's responsiveness to questions as well. Highly recommended! When's the cryptography course coming out?

Great course! I really like the way he explains everything with the drawings and code examples. It really gives you a solid foundation (and much more). So far, I really learned a lot! The only tip I can think of: I found the lab setup a bit confusing with the different versions and because I didn't understand Docker yet. There are documents included on the site but it would also be nice to have a short video explaining the basics of how to setup these labs.

I haven't finished this course but so far I have really enjoyed the content. I have taken a computer networks class before, but I still find the way that Prof. Du presented the material very informative to me. In particular, I find a lot of practical advice and live demos which really solidifies my knowledge about the protocols. Also, analogies are used properly to clear up concepts. This is definitely a top class by any standard!

I'm so glad to have enrolled in both the courses. Really appreciate all your efforts for comprehensively covering the topic of internet security; and to make such a complex topic relatively easy for students to understand. What a knowledgeable and sincere person (thank you, Prof Wenliang Du); who makes every attempt to help students learn core fundamentals and then help them scale up to advance levels. Thank you!

Fantastic course, the style of teaching is perfect for me. This is not just a banal course on how to use tools (there are hundrends of those), you will also learn the basics for writing your own. This course teaches the idea behind attacks in a in-depth way and exposes the network theory you need know to understand what's happening under the hood. The SEED Labs are extremely good and they give you an opportunity to test what you've learned.