Multi-Instance IS-IS One of the nice things about IS-IS is the ability to run IPv6 and IPv4 in the same protocol, over a single instance. So long as the two topologies are congruent, deploying v6 as dual stack is very simply. But what if your topologies are not congruent? The figure below illustrates the difference.…
I ran into an article over at the Register this week which painted the entire networking industry, from vendors to standards bodies, with a rather broad brush. While there are true bits and pieces in the piece, some balance seems to be in order. The article recaps a presentation by Peyton Koran at Electronic Arts…
Our guests are Russ White, a network architect at LinkedIn; and Sue Hares, a consultant and chair of the Inter-Domain Routing Working Group at the IETF. They discuss the history of BGP, the original problems it was intended to solve, and what might change. This is an informed and wide-ranging conversation that also covers whitebox,…
Looking at the capabilities of any given protocol running in our networks today, it certainly seems there are few use cases left the protocol cannot support. In fact, modern interior gateway protocols have become so capable that it almost seems like we only need one to support everything. This is not reality, of course—there are…
I sat with Greg, Kathleen, and Alia to talk about “ordinary engineers” getting involved in the IETF while we were in Prague. Believe it or not, this time I didn’t get out into the city at all other than walking between the hotel I was staying at and the venue hotel. I try to always…
The IETF published RFC8200 last week, which officially makes IPv6 an Internet Standard. While this move was a long time coming—IPv6 has now reached about 20% deployment—a more interesting question is: what has changed since RFC2460, which was a draft standard, was published in 2013? After all, the point of moving from the experimental to…
While most network engineers do not spend a lot of time thinking about environmentals, like power and cooling, physical space problems are actually one of the major hurdles to building truly large scale data centers. Consider this: a typical 1ru rack mount router weighs in at around 30 pounds, including the power supplies. Centralizing rack…
There has been a lot of chatter recently in the 5G wireless world about network slices. A draft was recently published in the IETF on network slices—draft-gdmb-netslices-intro-and-ps-02. But what, precisely, is a network slice? Perhaps it is better to begin with a concept most network engineers already know (and love)—a virtual topology. A virtual topology…
[time-span] There are—in theory—three ways BGP can be deployed within a single AS. You can deploy a full mesh of iBGP peers; this might be practical for a small’ish deployment (say less than 10), but it quickly becomes a management problem in larger, or constantly changing, deployments. You can deploy multiple BGP confederations; creating internal…
Is it time for the IETF to give up? Over at CircleID, Martin Geddes makes a case that it is, in fact, time for the IETF to “fade out.” The case he lays out is compelling—first, the IETF is not really an engineering organization. There is a lot of running after “success modes,” but very…