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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".

IPv6 Presents a Security Paradox for the Network

The capabilities IPv6 provides will enhance online security, but the shift to the new Internet address scheme may also present risks if not properly managed. Previously, Internet security was largely an after-thought for the early Internet, as its primary purpose was to facilitate open, end-to-end, any-to-any communications and information exchange for bridging and accelerating research efforts. Today, we have a much more complex online ecosystem that spans billions of users across the globe and serves not only as an engine for e-commerce, but as an engine for all commerce.

To Flat or To Cap?

I don't think it's a surprise to anyone, but it's the Christmas season again and doubtless a large number of television sets will be sold as part of the annual retail festivities. But these days the devices for sale in the shops are not just televisions: today's television is perhaps better described as a media computer with a very large display. Sure, the device can tune in to radio transmissions and display them... but the device also is equipped with either a WiFi or an Ethernet jack, or both. This alone sounds like a relatively innocuous addition to the television, but it's providing to be a highly disruptive change in the traditional Internet market space.

Looking Back on 2012: What’s in our Rearview Mirror?

Well, 2012 is almost over, and we can now reflect on the major events that hit our industry this year. If I had to choose the top three trends from the past 12 months, they would have to be: 1. Over-the-top (OTT) services; 2. IPv6 deployments (finally!); 3. TR-069 adoption. Let's examine each of these in more detail.

The Case for Hot Swappable Nameservers

Earlier this week we announced our "Proactive Nameservers", which is just marketing speak for what it really is: hot swappable nameservers or nameserver fail over. What is it? ... It's basically what every webmaster, IT department and CTO wishes they had set up before...

Industry Structure at the Core of WCIT Problems

At the WCIT in Dubai it is interesting to follow the debates surrounding the many issues being addressed at this world congress. There are the issues of internet governance in the broadest sense of the word - these have received widespread attention. But if we look at the core issues that an organisation such as the ITU can address then the scope widens - to topics such as the rules for the International Telecommunications Regulations (ITRs), and particularly those in relation to the rules for rates and charges.

The Future of Home Networking: A Problem Statement

I'm a network engineer, and like many engineers I often gravitate to the big projects; large networks with problems of scale and complexity in my case. However, I also consider myself a student of Occam's razor and often quote Antoine de Saint-Exupéry: "perfection is reached not when there is nothing left to add, but when there is nothing left to take away." In this spirit of "less is more" I have recently become intrigued by the problems appearing in home networking.

Superstorm Sandy and the Global Internet

The Internet has managed to collect its fair share of mythology, and one of the more persistent myths is that from its genesis in a cold war US think tank in the 1960's the Internet was designed with remarkable ability to "route around damage." Whether the story of this cold war think tank is true or not, the adoption of a stateless forwarding architecture, coupled with a dynamic routing system, does allow the network to "self-heal" under certain circumstances. Can we see this self-healing in today's network?

Syria Disconnects From The Internet

This morning brought word that all Internet connections into Syria had been severed. Internet monitoring firm Renesys was among the first to report the news in a blog post that they have continued to update. That news was subsequently confirmed by other sites and services... Multiple reports indicate that all Internet, cell phone and landline connections to all or most of the country have been severed.

IPv6: A 2012 Report Card

The Gogonet Live conference in San Jose witnessed outstanding presentations by several federal administrations including Veteran Affairs, NASA and SPAWAR, sharing their experience and progress towards IPv6 adoption. Furthermore, the NIST compliance report leaves no agency any place to hide. The report card is there for everybody to see. In spite of regular jabs and criticisms, the US Federal Government has done a remarkable job.