colorful laptop

Routing Without Rumor: Securing the Internet’s Routing System

This article is based on a paper originally published as part of the Global Commission on the Stability of Cyberspace’s Cyberstability Paper Series, “New Conditions and Constellations in Cyber,” on Dec. 9, 2021.

The Domain Name System has provided the fundamental service of mapping internet names to addresses from almost the earliest days of the internet’s history. Billions of internet-connected devices use DNS continuously to look up Internet Protocol addresses of the named resources they want to connect to — for instance, a website such as Once a device has the resource’s address, it can then communicate with the resource using the internet’s routing system.

Just as ensuring that DNS is secure, stable and resilient is a priority for Verisign, so is making sure that the routing system has these characteristics. Indeed, DNS itself depends on the internet’s routing system for its communications, so routing security is vital to DNS security too.

Globe with caution signs

Observations on Resolver Behavior During DNS Outages

When an outage affects a component of the internet infrastructure, there can often be downstream ripple effects affecting other components or services, either directly or indirectly. We would like to share our observations of this impact in the case of two recent such outages, measured at various levels of the DNS hierarchy, and discuss the resultant increase in query volume due to the behavior of recursive resolvers.


Ongoing Community Work to Mitigate Domain Name System Security Threats

For over a decade, the Internet Corporation for Assigned Names and Numbers (ICANN) and its multi-stakeholder community have engaged in an extended dialogue on the topic of DNS abuse, and the need to define, measure and mitigate DNS-related security threats. With increasing global reliance on the internet and DNS for communication, connectivity and commerce, the members of this community have important parts to play in identifying, reporting and mitigating illegal or harmful behavior, within their respective roles and capabilities.


Information Protection for the Domain Name System: Encryption and Minimization

This is the final in a multi-part series on cryptography and the Domain Name System (DNS).

In previous posts in this series, I’ve discussed a number of applications of cryptography to the DNS, many of them related to the Domain Name System Security Extensions (DNSSEC).

In this final blog post, I’ll turn attention to another application that may appear at first to be the most natural, though as it turns out, may not always be the most necessary: DNS encryption. (I’ve also written about DNS encryption as well as minimization in a separate post on DNS information protection.)


Securing the DNS in a Post-Quantum World: Hash-Based Signatures and Synthesized Zone Signing Keys

This is the fifth in a multi-part series on cryptography and the Domain Name System (DNS).

In my last article, I described efforts underway to standardize new cryptographic algorithms that are designed to be less vulnerable to potential future advances in quantum computing. I also reviewed operational challenges to be considered when adding new algorithms to the DNS Security Extensions (DNSSEC).

In this post, I’ll look at hash-based signatures, a family of post-quantum algorithms that could be a good match for DNSSEC from the perspective of infrastructure stability.


Newer Cryptographic Advances for the Domain Name System: NSEC5 and Tokenized Queries

This is the third in a multi-part blog series on cryptography and the Domain Name System (DNS).

In my last post, I looked at what happens when a DNS query renders a “negative” response – i.e., when a domain name doesn’t exist. I then examined two cryptographic approaches to handling negative responses: NSEC and NSEC3. In this post, I will examine a third approach, NSEC5, and a related concept that protects client information, tokenized queries.


Cryptographic Tools for Non-Existence in the Domain Name System: NSEC and NSEC3

This is the second in a multi-part blog series on cryptography and the Domain Name System (DNS).

In my previous post, I described the first broad scale deployment of cryptography in the DNS, known as the Domain Name System Security Extensions (DNSSEC). I described how a name server can enable a requester to validate the correctness of a “positive” response to a query — when a queried domain name exists — by adding a digital signature to the DNS response returned.

Man looking at technical imagery

The Domain Name System: A Cryptographer’s Perspective

This is the first in a multi-part blog series on cryptography and the Domain Name System (DNS).

As one of the earliest protocols in the internet, the DNS emerged in an era in which today’s global network was still an experiment. Security was not a primary consideration then, and the design of the DNS, like other parts of the internet of the day, did not have cryptography built in.

Lock image and DNS

A Balanced DNS Information Protection Strategy: Minimize at Root and TLD, Encrypt When Needed Elsewhere

Over the past several years, questions about how to protect information exchanged in the Domain Name System (DNS) have come to the forefront.

One of these questions was posed first to DNS resolver operators in the middle of the last decade, and is now being brought to authoritative name server operators: “to encrypt or not to encrypt?” It’s a question that Verisign has been considering for some time as part of our commitment to security, stability and resiliency of our DNS operations and the surrounding DNS ecosystem.