DNS

Sponsored
by

DNS / Most Viewed

An Attack on DNS is an Attack on the Internet

On Saturday Aug 7th, DNS provider DNS Made Easy was the target of a very large denial of service attack. As far as can be determined the total traffic volume exceeded 40 Gigabit/second, enough to saturate 1 million dialup Internet lines. Several of DNS Made Easy's upstream providers had saturated backbone links themselves. There are indications that not only DNS Made Easy suffered from this attack, but the Internet as a whole. more

The State of DNS Abuse: Moving Backward, Not Forward

ICANN's founding promise and mandate are optimistic -- ensure a stable and secure internet that benefits the internet community as a whole. Recent months, however, have highlighted the uncomfortable truth that ICANN's and the industry's approach to DNS abuse is actually moving backward, ignoring growing problems, abdicating on important policy issues, and making excuses for not acting. Further, the impending failure of ICANN's new WHOIS policy to address cybersecurity concerns will add fuel to the fire, resulting in accelerating DNS abuse that harms internet users across the globe. more

Domain Names Can’t Be Trespassed: Utube.com v. YouTube

Boy, this case got a lot of attention when it was first filed (which isn't surprising; YouTube lawsuits usually do). You may remember the story: the plaintiff is a dealer of used tube mills, used pipe mills and used pollforming machines. The plaintiff operated a website at utube.com. As you might expect, like most other industrial B2B vendors' websites, utube.com had a small but targeted audience. With the phenomenal and quick rise in popularity of YouTube, a lot of web users mistyped youtube.com and entered utube.com instead, causing utube.com to suddenly experience disproportionate popularity. Unfortunately for the plaintiff, few of these visitors were interested in pollforming machines... The plaintiff sued YouTube for trademark infringement... more

Domain Front Running by Registrars Continues to Draw Attention

In response to accusations lodged yesterday in a post on the DomainState forum, NSI has issued a statement which essentially admits that it engages in a form of domain front running. No one has challenged domain Front Running by registrars in the courts, likely because the practice is new and since the loss of a single domain would not typically generate a level of damages to support litigation. But litigation over this arguably fraudulent domain practice by registrars is both viable and likely inevitable... more

Splitting the Root: It’s Too Late

One of the consistent chants we've always heard from ICANN is that there has to be a single DNS root, so everyone sees the same set of names on the net, a sentiment with which I agree. Unfortunately, I discovered at this week's ICANN meeting that due to ICANN's inaction, it's already too late. Among the topics that ICANN has been grinding away at is Internationalized Domain Names (IDNs) that contain characters outside the traditional English ASCII character set... ICANN has tied itself with the issue of homographs, different characters that look the same or mean the same thing. Once people noticed that IDNs let you register different names that look the same, the intellectual property crowd that has always had a mysteriously great influence on ICANN went into a tizzy and they went into lengthy discussions on what to do about them... more

IP or NAT IP: Mostly IP

There seems to be a heated debate on this site about NAT (network-address translation). What came as a surprise to me is that a lot of the arguments seem to reside in ideological point of views which obscure the real issues at hand -- IP addressing, IP security -- and have little to do with NAT's actual merits or drawbacks. more

Hypertext Mail Protocol (a.k.a. Stub Email): A Proposal

Back in the days of dial-up modems and transfer speeds measured in hundreds of bits per second, unwanted email messages were actually felt as a significant dent in our personal pocketbooks. As increases in transfer speeds outpaced increases in spam traffic, the hundreds of unwanted emails we received per week became more of a nuisance than a serious financial threat. Today sophisticated spam filters offered by all major email providers keep us from seeing hundreds of unwanted emails on a daily basis, and relatively infrequently allow unwanted messages to reach our coveted Inboxes. So, to some degree, the spam problem has been mitigated. But this "mitigation" requires multiple layers of protection and enormous amounts of continually-applied effort. more

Wall Street Journal Article on Whois Privacy

Today's Wall Street Journal discusses the fight over Whois privacy. The article on the front page of the Marketplace section starts by discussing how the American Red Cross and eBay use the Whois database to track down scammers: "Last fall, in the wake of Hurricane Katrina, the American Red Cross used an Internet database called "Whois" that lists names and numbers of Web-site owners to shut down dozens of unauthorized Web sites that were soliciting money under the Red Cross logo. Online marketplace eBay Inc. says its investigators use Whois hundreds of times a day..." more

DNS Firewalls In Action - RPZ vs. Spam

In general, a network firewall is just a traffic filter... Filtering rules can be anything from "allow my web server to hear and answer web requests but not other kinds of requests" to "let my users Ping the outside world but do not let outsiders Ping anything on my network." The Internet industry has used firewalls since the mid-1980's and there are now many kinds, from packet layer firewalls to web firewalls to e-mail firewalls. Recently the DNS industry has explored the firewall idea and the results have been quite compelling. In this article I'm going to demonstrate a DNS firewall built using RPZ (Response Policy Zones) and show its potential impact on e-mail "spam". more

Defending Networks Against DNS Rebinding Attacks

DNS rebinding attacks are real and can be carried out in the real world. They can penetrate through browsers, Java, Flash, Adobe and can have serious implications for Web 2.0-type applications that pack more code and action onto the client. Such an attack can convert browsers into open network proxies and get around firewalls to access internal documents and services. It requires less than $100 to temporarily hijack 100,000 IP addresses for sending spam and defrauding pay-per-click advertisers. Everyone is at risk and relying on network firewalls is simply not enough. In a paper released by Stanford Security Lab, "Protecting Browsers from DNS Rebinding Attacks," authors Collin Jackson, Adam Barth, Andrew Bortz, Weidong Shao, and Dan Boneh provide ample detail about the nature of this attack as well as strong defenses that can be put in place in order to help protect modern browsers. more

Technical Comments on Mandated DNS Filtering Requirements of H. R. 3261 (“SOPA”)

About two months ago, I got together with some fellow DNS engineers and sent a letter to the U. S. Senate explaining once again why the mandated DNS filtering requirements of S. 968 ("PIPA") were technically unworkable. This letter was an updated reminder of the issues we had previously covered... In the time since then, the U. S. House of Representatives has issued their companion bill, H. R. 3261 ("SOPA") and all indications are that they will begin "markup" on this bill some time next week. more

A Question of DNS Protocols

One of the most prominent denial of service attacks in recent months was one that occurred in March 2013 between Cloudflare and Spamhaus... How did the attackers generate such massive volumes of attack traffic? The answer lies in the Domain Name System (DNS). The attackers asked about domain names, and the DNS system answered. Something we all do all of the time of the Internet. So how can a conventional activity of translating a domain name into an IP address be turned into a massive attack? more

Network Solutions Under Large Scale DDoS Attack, Millions of Websites Potentially Unreachable

Network Solutions is having problems with "all" its name servers, according to their tech support and a recent post on North American Network Operators' Group (NANOG) mailing list indicates that it has been under very large-scale UDP/53 DDoS attack for the last 48 hour period. As a result, domain names hosted with Network Solutions' Worldnic have been affected. Network Solutions is one of the leading domain registrars and DNS hosting providers in the world, managing more than 7.6 million domain names. more

Fight Spam With the DNS, Not the CIA

It seems like spam is in the news every day lately, and frankly, some of the proposed solutions seem either completely hare-brained or worse than the problem itself. I'd like to reiterate a relatively modest proposal I first made over a year ago: Require legitimate DNS MX records for all outbound email servers.

MX records are one component of a domain's Domain Name System (DNS) information. They identify IP addresses that accept inbound email for a particular domain name. To get mail to, say, linux.com, a mail server picks an MX record from linux.com's DNS information and attempts to deliver the mail to that IP address. If the delivery fails because a server is out of action, the delivering server may work through the domain's MX records until it finds a server that can accept the mail. Without at least one MX record, mail cannot be delivered to a domain.
 more

Whither DNS?

The Domain Name System is often though of as an integral part of the Internet. Without it, how can you ever locate anything? Well, quite easily, thank you very much. DNS is used implicitly for many services, such as web browsing. It also includes explicit extensions for a few applications such as e-mail. (I'm talking here about DNS the system, not DNS the technology that can be re-purposed to things like ENUM.) But the most notable thing about DNS is its receding importance... more