BGP Route Replication in MPLS/VPN PE-routers
Whenever I’m explaining MPLS/VPN technology, I recommend using the same route targets (RT) and route distinguishers (RD) in all VRFs belonging to the same simple VPN. The Single RD per VPN recommendation doesn’t work well for multi-homed sites, so one might wonder whether it would be better to use a different RD in every VRF. The RD-per-VRF design also works, but results in significantly increased memory usage on PE-routers.
Long-Distance Workload Mobility in Perspective
Sometime in 2012, Chuck Hollis described how some of EMC customers use long-distance workload mobility. Not surprisingly, he focused on the VPLEX Metro part of the solution and didn’t even mention the earth-flattening requirements this idea imposes on the network. I guess you already know my views on that topic, but regardless of my personal opinions, he got me curious.
Analyst-driven IPv6 deployment
Straight from the rumor mill (source, translated):
One of German ISPs is actually quite busy rolling out IPv6 after their CFO got a call from a stock analyst right during the RIPE meeting, asking questions “so what are your IPv6 plans?” – “none, what is IPv6?” – “oh, this is not so good”… full panic down the management chain…
Proves the everlasting wisdom from Martin Levy (source, the rest of article is not worth reading):
Can I download the webinar recordings?
I get this question every second week or so – someone would like to buy the yearly subscription and wonders whether she’ll be able to watch the recordings on her iPad.
Short answer: Yes for most webinars.
Update 2012-07-13: All webinars recorded prior to July 1st 2012 are available in ARF format. Many of them are also available in edited MP4 format.
Why Do Internet Exchanges Need Layer-2?
My tweet about the latest proof of my layer-2 = single failure domain claim has raised numerous questions about the use of bridging (aka switching) within Internet Exchange Points (IXP). Let’s see why most IXPs use L2 switching and why L2 switching is the simplest solution to the problem they’re solving.
Does CPU-based forwarding performance matter for SDN?
David Le Goff sent me several great SDN-related questions. Here’s the first one:
What is your take on the performance issue with software-based equipment when dealing with general purpose CPU only? Do you see this challenge as a hard stop to SDN business?
Short answer (as always) is it depends. However, I think most people approach this issue the wrong way.
Legacy Protocols in OpenFlow-Based Networks
This post is probably a bit premature, but I’m positive your CIO will get a visit from a vendor offering clean-slate OpenFlow/SDN-based data center fabrics in not so distant future. At that moment, one of the first questions you should ask is “how well does your new wonderland integrate with my existing network?” or more specifically “which L2 and L3 protocols do you support?”
Just what you need: Positive Factors in Childhood Development
A friendly offer to write a guest blog post for my blog just landed in my Inbox. It's amazing what some people think networking engineers really need.

