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NANOGGING

There are many network operator group meetings being held these days. Even in the backwater of the South Pacific where I live there is now AUSNOG, and NZNOG is just next door in New Zealand. We now have MENOG in the Middle East and AFNOG in Africa. The original NOG was the North American Network Operators Group (NANOG), and they have the T-Shirts to prove it! NANOG meets three times a year, and I attended NANOG 41 in October 2007. NANOG meetings cover a broad variety of topics, from operational tools, measurement, and peering practices through to a commentary on the state of the Internet industry. Here are my impressions of the meeting. more

IPv6 Deployment: A Very Complex Time Bomb with an Uncertain Trigger Date

I did a 2 hour interview on October 23rd with John Curran, Board Chair of ARIN the North American Regional Internet Routing Registry for the last decade. I now understand what is at stake with IPv6. Outside of a key core group of network engineers I think darn few people do understand. And not all of them agree on how the scenario plays out though virtually all say the situation is very serious. John believes that it is huge. It is as big as Y2K except no one knows a precise date by which everything has to be done... 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

Transition to IPv6 Address

Last month's column looked at the exhaustion of the IPv4 unallocated address pool and the state of preparedness in the Internet to grapple with this issue... There has been a considerable volume of discussion in various IPv6 and address policy forums across the world about how we should respond to this situation in terms of development of address distribution policies. Is it possible to devise address management policies that might both lessen some of the more harmful potential impacts of this forthcoming hiatus in IPv4 address supply, and also provide some impetus to industry to move in the originally intended direction to transition into an IPv6 network? more

Scarcity of IPv4 Addresses

My friend Kurtis writes in his blog some points he has been thinking of while discussing "when we run out of IPv4 addresses". In reality, as he points out so well, we will not run out. It will be harder to get addresses. It is also the case that unfortunately people that push for IPv6 claim IPv6 will solve all different kinds of problem. Possibly also the starvation problems in the world... more

The End of the (IPv4) World is Nigher!

Funny how some topics seem sit on a quiet back burner for years, and then all of a sudden become matters of relatively intense attention. Over the past few weeks we've seen a number of pronouncements on the imminent exhaustion of the IP version 4 address pools. Not only have some of the Regional Internet Registries (RIRs) and some national registry bodies made public statements on the topic, we've now seen ICANN also make its pronouncement on this topic... Why the sudden uptake of interest in this topic? I suspect that a small part of this may be my fault! more

How Many Bots? How Many Botnets?

We touched on this subject in the past, but recently Rich Kulawiek wrote a very interesting email to NANOG to which I replied, and decided to share my answer here as well: I stopped really counting bots a while back. I insisted, along with many friends, that counting botnets was what matters. When we reached thousands we gave that up. We often quoted anti-nuclear weapons proliferation sentiments from the Cold War, such as: "why be able to destroy the world a thousand times over if once is more than enough?" we often also changed it to say "3 times" as redundancy could be important... 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

Addressing the Future Internet

What economic and social factors are shaping our future needs and expectations for communications systems? This question was the theme of a joint National Science Foundation (NSF) and Organisation for Economic Co Operation and Development (OECD) workshop, held on the 31st January of this year. The approach taken for this workshop was to assemble a group of technologists, economists, industry, regulatory and political actors and ask each of them to consider a small set of specific questions related to a future Internet. Thankfully, this exercise was not just another search for the next "Killer App", nor a design exercise for IP version 7. It was a valuable opportunity to pause and reflect on some of the sins of omission in today's Internet and ask why, and reflect on some of the unintended consequences of the Internet and ask if they were truly unavoidable consequences... more

The Fragile Network

One of the more persistent founding myths around the internet is that it was designed to be able to withstand a nuclear war, built by the US military to ensure that even after the bombs had fallen there would still be communications between surviving military bases. It isn't true, of course. The early days of the ARPANET, the research network that predated today's internet, were dominated by the desire of computer scientists to find ways to share time on expensive mainframe computers rather than visions of Armageddon. Yet the story survives... more

P2P as a New Spam Medium, Moving From PoC to Full Operations

Spam on P2P networks used to be mainly with advertising inside downloaded movies and pictures (mainly pornographic in nature), as well as by hiding viruses and other malware in downloaded warez and most any other file type (from zip archives to movie files). Further, P2P networks were in the past used for harvesting by spammers. Today, P2P has become a direct to customer spamvertizing medium. This has been an ongoing change for a while. As we speak, it is moving from a proof of concept trial to a full spread of spam, day in, day out... more

Taking Aim at 8 Myths about ENUM

ENUM has a critical role to play in telephony services convergence. Although many carriers are adopting ENUM there are myths swirling around the confuse newcomers. In data networks, the domain name system (DNS) is responsible for converting Uniform Resource Locators (URL's) to IP addresses in order to route data traffic. The ENUM protocol performs a similar essential function of linking E.164 telephone numbers to Universal Resource Identifiers (URIs) -- enabling communication services to use traditional phone numbers to set up calls over IP networks. Unfortunately, there's a good deal of hype and confusion around ENUM, which might lead carriers to delay ENUM implementations. That delay would be a mistake... 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

Worm Propagation Strategies in an Ipv6 Internet

A recent paper called "Worm Propagation Strategies in an IPv6 Internet", written by Steven M. Bellovin, Angelos Keromytis, and Bill Cheswick, examines whether or not the deployment of IPv6 will in fact provide a substantial level of barrier against worms. Shared below are the introductory paragraphs from this paper. "In recent years, the internet has been plagued by a number of worms. One popular mechanism that worms use to detect vulnerable targets is random IP address-space probing..." 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