The evolution of wired access networks for suburban reticulation has been driven by a special set of economic and technical circumstances. Infrastructure assets are in this sector need to have an extended service life in order to by financially viable. While optical technology continues to evolve rapidly the challenge is to map this changing technology on to a fixed fibre cable plant.
In the IANA IPv4 Address registry a block of addresses, 240.0.0.0/4 is marked as reserved for "Future Use"". If we have run out of available IPv4 addresses, then why are some quarter of a billion IPv4 addresses still sitting idle in an IANA registry waiting for an undefined Future Use?
There was, as usual, a lot of work in the area of Inter-Domain Routing at IETF 120. There were a few routing-related topics that at IETF 120 that caught my attention.
It has been an enduring fascination to see how we could use packet networking in the context of digital communications in space. Why can't we just use the IP protocol suite and declare success? The tricky issue with space is that it is really very big!
As usual, the recent IETF meeting contained a large set of topics related to the Domain Name Systems and its operation. Here's a quick rundown on some DNS topics that caught my eye.
On the topic of TCP performance optimisation I’d like to dwell on one particular presentation from the ACM/IRTF Applied Networking Research Workshop held at IETF 120, "BBRv3 in the public Internet: a boon or a bane?"
>To ensure service consistency in a Content Distribution Network (CDN) replicated instances of the content are named with the same DNS name, and the DNS conventionally offers the same resolution outcome to each user when they query for the IP address of the content server. How can the CDN "steer" each user to the closest instance of the desired content to optimise the subsequent content transaction? At the same time the user is revealing their location within the network to inform this steering decision. To what extent is such a steering function compromising the privacy expectations of users with respect to the location and their online actions?
The choice of UDP as the default transport for the DNS was not a completely unqualified success. On the positive side, the stateless query/response model of UDP has been a good fit to the stateless query/response model of DNS transactions between a client and a server. On the other hand, these same minimal overheads imply that DNS over UDP cannot perform prompt detection of packet loss and cannot efficiently defend itself against various approaches to tampering with the DNS, such as source address spoofing, payload alteration and third-party packet injection. Perhaps most importantly, the way UDP handles large payloads is a problem.
The DNS is a crucial part of the Internet's architecture. However, the DNS is not a rigid and unchanging technology. It has changed considerably over the lifetime of the Internet and here I’d like to look at what’s changed and what’s remained the same.
RIPE 88 was held in May 2024 at Krakow, Poland. Here’s as summary of some of the routing topics that were presented at that meeting that I found to be of interest.
RIPE 88 was held in May 2024 at Krakow, Poland. Here’s as summary of some of the DNS topics that were presented at that meeting that I found to be of interest.
Through the lack of clear signals of general adoption of DNSSEC over three decades, then is it time to acknowledge that DNSSEC is just not going anywhere? Is it time to call it a day for DNSSEC and just move on?
Let's look at the Starlink at a protocol level, and how TCP, the workhorse transport protocol of the Internet, interacts with the somewhat unique characteristics of Starlink's service.
These days its up to IPv6 Service providers to determine what IPv6 address prefix length they assign to each customer. This leads to the question: What lengths are commonly used for customer assignments? Let's see if we can answer it.
It's a welcome sight to see a careful and thoughtful analysis of a service outage. One such instance was a presentation by .nz's Josh Simpson at the recent NZNOG meeting, reporting on a service outage for .nz domains.
The Internet is rapidly shifting to a name-based network and the DNS is now the underlying technology that lies the core of today's network. So, let’s see what we are currently thinking about in terms of names and the DNS at the recent IETF meeting.
I had the opportunity to participate in the New Zealand Network Operators Group meeting (NZNOG) in Nelson earlier this month. This article was prompted by a presentation from Thomas Weible of Flexoptix at NZNOG on the topic of Coherent Optical Transceivers.
We repeat the measurements of the behaviour of the DNS when processing truncated UDP responses, but this time we've constrained the measurement so that only IPv6-capable DNS resolvers are being measured. Does this make the results better or worse?
We repeat the measurements of the behaviour of the DNS when processing truncated UDP responses, but this time we've constrained the measurement so that only IPv6-capable DNS resolvers are being measured. Does this make the results better or worse?
Yet another DNS vulnerability has been exposed. The language of the press release revealing the vulnerabil;ity is certainly dramatic, with "devasting consequences" and the threat to "completely disable large parts of the worldwide Internet."" If this is really so devastating then perhaps we should look at this in a little more detail to see what’s going on, how this vulnerability works, and what the response has been.