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DHCP for IPv4 vs. IPv6 - What You Need to Know

Dynamic Host Configuration Protocol (DHCP) is a protocol intended to enable machines (servers, game consols, etc) wishing to be "online" the ability to request Internet Protocol information from a DHCP server automatically. ... In this article we will begin to outline some of the fundamental differences between DHCPv4 and DHCPv6, explore historical uses of DHCPv4 and how those concepts will adapt/change in IPv6. more

DNS Changer

One fine night in November 2011 I got an opportunity to get my hands dirty, working on a project for the United States Federal Bureau of Investigation (FBI). They were planning to seize a bunch of computing assets in New York City that were being used as part of a criminal empire that we called "DNS Changer" since that was the name of the software this gang used to infect a half million or so computers. more

Why I Am Participating in the ORSN Project

As a long time supporter of the universal namespace operated by IANA, it may come as a surprise that I have joined the Open Root Server Network project (ORSN). I'll try to explain what's going on and what it all means. ...If one of my kids, or anybody anywhere, sits down in front of a web browser and keys in a URL, it ought to just work. They ought to see the same web page that anybody else would see, no matter what country they're in or what their ISP wants or what their local church or government wants. This universality of naming is one of the foundations on which the Internet was built, and it is how the Internet fosters economic growth and social freedoms. It's what makes the Internet different from old Compuserve, old AOL, old MSN, old Minitel, and everything else that has come -- and gone -- before... more

How to Stop Spam

I got a letter the other day from AOL postmaster Carl Hutzler, about how the Internet community could get rid of spam, if it really wanted to. With his permission, here are some excerpts. "Spam is a completely solvable problem. And it does not take finding every Richter, Jaynes, Bridger, etc to do it (although it certainly is part of the solution). In fact it does not take email identity technologies either (although these are certainly needed and part of the solution)." more

IP Address Allocation vs. Internet Production I: Understanding the Relationship, and the Differences

It is sometimes said that: 'IP addresses are hoarded by "developed nations" - if only "underdeveloped" nations were given more IP addresses, the Internet would grow more/better...' Assertions like this mistakenly conflate the administrative process of requesting and receiving public IP addresses with the economic or commercial act of routing IP addresses - of engaging in what is sometimes called "Internet production." The former, administrative process involves relatively little in the way of overhead, and confers nothing more than the potential to develop public Internet resources -- i.e., to create new Internet users (provide access) and/or Internet uses (provide content and other online services). more

Examining Two Well-Known Attacks on VoIP

VoIP is here to stay. In fact many incumbent telecommunication carriers have started offering VoIP service for sometime and several new VoIP service providers have emerged. Aside from issues such as quality of service, the aspect of security, or lack thereof, is misunderstood by some of the VoIP service providers. This purpose of this article is to discuss two of the most well known attacks that can be carried out in current VoIP deployments. more

IPv6: Extinction, Evolution or Revolution?

For some years now the general uptake of IPv6 has appeared to be "just around the corner". Yet the Internet industry has so far failed to pick up and run with this message, and it continues to be strongly reluctant to make any substantial widespread commitment to deploy IPv6. Some carriers are now making some initial moves in terms of migrating their internet infrastructure over to a dual protocol network, but for many others it's a case of still watching and waiting for what they think is the optimum time to make a move. So when should we be deploying IPv6 services? At what point will the business case for IPv6 have a positive bottom line? It's a tough question to answer, and while advice of "sometime, probably sooner than later" is certainly not wrong, it's also entirely unhelpful as well! more

NAT: Just Say No

Fueled by the lack of public IP addresses, 70% of Fortune 1000 companies have been forced to deploy NATs (Source: Center for Next Generation Internet). NATs are also found in hundreds of thousands of small business and home networks where several hosts must share a single IP address. It has been so successful in slowing the depletion of IPv4 addresses that many have questioned the need for IPv6 in the near future. However, such conclusions ignore the fact that a strategy based on avoiding a crisis can never provide the long-term benefits that solving the underlying problems that precipitated the crisis offers. more

Verizon Mandates IPv6 Support for Next-Gen Cell Phones

Cell phone carriers have seen a huge growth in wireless data usage. The iPhone is selling like hotcakes, and its users generate large amounts of traffic. Not surprisingly, as cellular providers deploy faster network technologies, users generate even more data... more

DNS, DNSSEC and Google’s Public DNS Service

For some time now we've been tracking the progress of the deployment of DNSSEC in the Internet. Its been a story of an evolution of the measurement technique... In the process we've learned perhaps more than we had wanted to about the behaviour of Flash engines, Apache web servers and FreeBSD system tuning, and also learned much more than we had anticipated about the finer details of Google's online ad presentation behaviour. But one thing we did not see in all of this was any large scale jumps in the level of client use of DNSSEC validation over this period at the start of the year. more

WiMAX vs. LTE

Mobile WiMAX, with the release of 2×2 MIMO chips in 2008, gives WiMAX a lead of two or so years on its major competitor -- the 3GPP's LTE. However, 3G cellphones using 3GPP UMTS technologies, extended to higher speeds with HSPA, is widely used in handsets in many countries. In North America, 3GPP2 CDMA2000 and EV-DO are widely used, but these are likely to be replaced over time by LTE and to some extent WiMAX. more

Internet Security Marketing: Buyer Beware

As security breaches increasingly make headlines, thousands of Internet security companies are chasing tens of billions of dollars in potential revenue. While we, the authors, are employees of Internet security companies and are happy for the opportunity to sell more products and services, we are alarmed at the kind of subversive untruths that vendor "spin doctors" are using to draw well-intentioned customers to their doors. Constructive criticism is sometimes necessarily harsh, and some might find the following just that, harsh. But we think it's important that organizations take a "buyers beware" approach to securing their business. more

A Fundamental Look at DNSSEC, Deployment, and DNS Security Extensions

In looking at the general topic of trust and the Internet, one of the more critical parts of the Internet's infrastructure that appears to be a central anchor point of trust is that of the Domain Name Service, or DNS. The mapping of "named" service points to the protocol-level address is a function that every Internet user relies upon, one way or another. The ability to corrupt the operation of the DNS is one of the more effective ways of corrupting the integrity of Internet-based applications and services. If an attacker can in some fashion alter the DNS response then a large set of attack vectors are exposed. ...The more useful question is whether it is possible to strengthen the DNS. The DNS is a query -- response application, and the critical question in terms of strengthening its function is whether it is possible to authenticate the answers provided by the DNS. DNSSEC provides an answer to this question. more

RFC 1918 Address Space: Why It Was Needed then and How It Will Change in IPv6!

Recently, my firm has seen a lot of interest come from Enterprises seeking IPAM/DNS tools. We predicted that IPv6 adoption and the need for automation software/tools would follow the Internet ecosystem's supply chain starting with Service Providers consisting of ISPs, I/PaaS, ASPs, then content providers (mostly a service really), then Enterprises, followed by SMBs & Consumers. While good for business, it has also forced us to revisit and think thru many TCP/IP protocol standards... more

Convergence: ENUM is a Big Deal

Convergence as a technology concept has been around for decades. Many have predicted the convergence of electronics and entertainment, of PC's and TV's, and more recently of WiFi and cellular. All of these areas are in fact undergoing various degrees of convergence but there is another area that many are not as familiar with. It is called ENUM...The idea can be extremely useful when you consider that most telephones are limited to twelve keys on a keypad. Ever tried to enter your alphanumeric login ID and password to a web site on a cell phone or Personal Digital Assistant? It is next to impossible! The biggest impact of ENUM will probably be for Voice Over IP (VoIP). In fact, it could be the tipping point. ENUM is a really big deal. more