* [Blog](https://www.paloaltonetworks.com/blog) * [Palo Alto Networks](https://www.paloaltonetworks.com/blog/corporate/) * PDNS # Palo Alto Networks ## PDNS [](https://www.paloaltonetworks.com/blog/2015/11/connecting-the-dots-in-cyber-threat-campaigns-part-2-passive-dns/) [Connecting the Dots in Cyber Threat Campaigns, Part 2: Passive DNS \------------------------------------------------------------------](https://www.paloaltonetworks.com/blog/2015/11/connecting-the-dots-in-cyber-threat-campaigns-part-2-passive-dns/) This is the second part of our series on "connecting the dots," where we investigate ways to link attacks together to gain a better understanding of how they are related. In Part 1, we looked at how domain WHOIS information can be used to identify connections between malicious domains and potentially the actors who own them. In Part 2 we dive into Passive DNS (PDNS), which allows analysts to look back in time and discover how a domain has been used in the past.... [Threat Prevention](https://www.paloaltonetworks.com/blog/category/threat-prevention-2/?ts=markdown) [Unit 42](https://unit42.paloaltonetworks.com) Nov 04, 2015 By [Bryan Lee](https://www.paloaltonetworks.com/blog/author/bryan-lee/?ts=markdown "Posts by Bryan Lee") ## Palo Alto Networks *** ** * ** *** [Announcements](https://www.paloaltonetworks.com/blog/category/announcement/?ts=markdown) *** ** * ** *** [Company \& Culture](https://www.paloaltonetworks.com/blog/category/company-culture/?ts=markdown) *** ** * ** *** [Points of View](https://www.paloaltonetworks.com/blog/category/points-of-view/?ts=markdown) *** ** * ** *** [Public Sector](https://www.paloaltonetworks.com/blog/category/public-sector/?ts=markdown) *** ** * ** *** [Products and Services](https://www.paloaltonetworks.com/blog/category/products-and-services/?ts=markdown) *** ** * ** *** [Partners](https://www.paloaltonetworks.com/blog/category/partners/?ts=markdown) *** ** * ** *** ### Subscribe to the Blog! 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