BGP in 2019 – Part 1

It has become a tradition (or quite possibly a habit) each January for me to report on the behaviour of the inter-domain routing system over the past year, looking in some detail at some metrics from the routing system that can show the essential shape and behaviour of the underlying…


Sizing the Buffer

Packet switched networks benefit from buffers within the network’s switches. In the simplest case, if two packets arrive at a switch at the same time and are destined to the same output port, then one packet will need to wait in a buffer while the other packet is sent on,…


What’s the Time?

Computers have always had clocks. Well maybe not clocks as you might think, but digital computers have always had oscillators, and if you hook the oscillator to a simple counter then you have a clock. The clock is not just there to tell the time, although it can do that,…


BGP in 2017

It has become either a tradition, or a habit, each January for me to report on the experience with the inter-domain routing system over the past year, looking in some detail at some metrics from the routing system that can show the essential shape and behaviour of the underlying interconnection…


Ripe 75

RIPE held its 75th meeting in Dubai in mid-October. As usual there was a diverse set of presentations covering a broad range of activities that are taking place on today’s Internet. The topics include issues relating to network operations, regulatory policies, peering and interconnection, communications practices within data centres, IPv6,…


IPv6 Fragmentation Extension Headers, Part 2

The first part of this article looked at what happens when an authoritative DNS server delivers fragmented UDP responses to DNS resolvers using IPv6. The result from this experiment was that: Some 37% of endpoints used IPv6-capable DNS resolvers that were incapable of receiving a fragmented IPv6 response over UDP.…


Notes from IETF 99 – The Other Bits

After pulling out the notes from the IEPG meeting and aspects of the DNS, here are the rest of the items that I personally found to be of interest at IETF 99 last week. IPv6 Operations – Apple’s Happier Eyeballs? The way in which browsers leverage the potential opportunities offered…


Notes from IETF 99 – The IEPG Meeting

It’s hard to classify the IEPG meetings that occur at the start of the IETF week. Many years ago they had a role in allowing network operators to talk to other operators about what they were seeing and what they were thinking about. Those days are long since over, and…


RIPE 74

RIPE 74 was held in May in Budapest, and as usual it was a meeting that mixed a diverse set of conversations and topics into a very busy week. Here are my impressions of the meeting drawn from a number of presentations that I found to be of personal interest.…


IETF 98 Report

The IETF meetings are relatively packed events lasting over a week, and it’s just not possible to attend every session. Inevitably each attendee follows their own interests and participates in Working Group sessions that are relevant and interesting to them. I do much the same when I attend IETF meetings.…