Update dnssec.md (#6251)

Update various topics with new links.

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Co-authored-by: dsh <daniel.s.holdsworth@gmail.com>

src/data/roadmaps/cyber-security/content/apt@l0BvDtwWoRSEjm6O0WDPy.md

@@ -21,3 +21,7 @@ Due to the sophisticated and persistent nature of APTs, they can be challenging
 - Employ advanced threat intelligence solutions to identify and anticipate potential APT campaigns.
 
 APT attacks can be damaging and disruptive to organizations, but understanding the nature of these threats and implementing a comprehensive security strategy can help minimize the risk and protect valuable assets. Remember, APTs are not just a concern for large enterprises and governments; organizations of all sizes can be targeted. Staying vigilant and proactive is key to staying safe from these advanced threats.
+
+Learn more from the following resources:
+
+- [@article@What Are Advanced Persistent Threats? - IBM](https://www.ibm.com/topics/advanced-persistent-threats)

src/data/roadmaps/cyber-security/content/comptia-a@lbAgU5lR1O7L_5mCbNz_D.md

@@ -36,4 +36,13 @@ Achieving a CompTIA A+ certification can offer several benefits, such as:
 
 Overall, if you're an aspiring IT professional, the CompTIA A+ certification is a great starting point to kick off your IT career and begin acquiring the skills and knowledge needed to thrive in this ever-evolving industry.
 
-- [@video@CompTIA A+ 220-1101 - Professor Messer](https://www.youtube.com/@professormesser/search?query=CompTIA%20220-1101%20A%2B)
+
+Learn more from the following resources:
+
+- [@official@CompTIA A+ Certification](https://www.comptia.org/certifications/a)
+- [@article@CompTIA A+ 220-1101 - Professor Messer's Course FREE](https://www.professormesser.com/free-a-plus-training/220-1101/220-1101-video/220-1101-training-course/)
+- [@article@CompTIA A+ 220-1102 - Professor Messer's Course FREE](https://www.professormesser.com/free-a-plus-training/220-1102/220-1102-video/220-1102-training-course/)
+- [@course@Total Seminars - CompTIA A+ Core 1 (220-1101)](https://www.udemy.com/course/comptia-aplus-core-1/)
+- [@course@Total Seminars - CompTIA A+ Core 2 (220-1102)](https://www.udemy.com/course/comptia-aplus-core-2/)
+- [@course@Dion Training - CompTIA A+ Core 1 (220-1101)](https://www.udemy.com/course/comptia-a-core-1/)
+- [@course@Dion Training - CompTIA A+ Core 2 (220-1102)](https://www.udemy.com/course/comptia-a-core-2//)

src/data/roadmaps/cyber-security/content/dnssec@LLGXONul7JfZGUahnK0AZ.md

@@ -0,0 +1,24 @@
+# DNSSEC
+
+DNS Security Extensions (DNSSEC) is a protocol designed to address security vulnerabilities in the Domain Name System (DNS). Here are the key points:
+
+- **Digital Signatures:**
+DNSSEC protects against attacks by digitally signing DNS data. These signatures ensure data validity and prevent tampering.
+
+- **Hierarchical Signing:**
+DNSSEC signs data at every level of the DNS lookup process. For instance, when looking up ‘google.com,’ the root DNS server signs a key for the .COM nameserver, which then signs a key for google.com’s authoritative nameserver.
+
+- **Backwards Compatibility:**
+DNSSEC doesn’t disrupt traditional DNS lookups; it adds security without breaking existing functionality. It complements other security measures like SSL/TLS.
+
+- **Chain of Trust:**
+DNSSEC establishes a parent-child trust chain from the root zone down to specific domains.
+Any compromise in this chain exposes requests to on-path attacks.
+
+Learn more from the following resources:
+
+- [@article@DNSSEC: What Is It and Why Is It Important? - ICANN](https://www.icann.org/resources/pages/dnssec-what-is-it-why-important-2019-03-05-en)
+- [@article@How DNSSEC Works - Cloudflare](https://www.cloudflare.com/dns/dnssec/how-dnssec-works/)
+- [@article@What is DNS security? - Cloudflare](https://www.cloudflare.com/learning/dns/dns-security/)
+- [@video@What is DNSSEC? - IBM](https://www.youtube.com/watch?v=Fk2oejzgSVQ)
+- [@video@(DNS) 101 Miniseries](https://www.youtube.com/playlist?list=PLTk5ZYSbd9MhMmOiPhfRJNW7bhxHo4q-K)