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+The content below comes mostly from Practical Networking's [Networking Fundamentals series](https://www.youtube.com/playlist?list=PLIFyRwBY_4bRLmKfP1KnZA6rZbRHtxmXi). If you prefer this content in video form, check out this video:
+
+* [Network Protocols - ARP, FTP, SMTP, HTTP, SSL, TLS, HTTPS, DNS, DHCP](https://www.youtube.com/watch?v=E5bSumTAHZE&list=PLIFyRwBY_4bRLmKfP1KnZA6rZbRHtxmXi&index=12)
+
+
 ## Network Protocols
 
 A set of rules and messages that form a standard. An Internet Standard.
@@ -111,7 +116,8 @@ If a section of a network is compromised, it can be quarantined, making it diffi
 
 ## Resources
 
+- [Networking Fundamentals](https://www.youtube.com/playlist?list=PLIFyRwBY_4bRLmKfP1KnZA6rZbRHtxmXi)
+- [Subnetting Mastery](https://www.youtube.com/playlist?list=PLIFyRwBY_4bQUE4IB5c4VPRyDoLgOdExE)
 - [Computer Networking full course](https://www.youtube.com/watch?v=IPvYjXCsTg8)
-- [Practical Networking](http://www.practicalnetworking.net/)
 
 See you on [Day 24](day24.md)