L2 MultiPath Basic Design Differences

With all the talk about Layer 2 Multipath (L2MP) designs going on, I just want to point out a fundamental change in the way many people approach network design. It’s seems that this point has been lost somewhere in the discussion of protocols.

The Spanning Tree Protocol blocks looped paths, and in a typical networks this means that bandwidth is unevenly distributed. Of course, we might use PVST or MST to provide a rough sharing of load by splitting the spanning tree preferences for different VLANs, but the design still doesn’t change overall. The basic point is that there is a LOT of bandwidth that is never evenly utilised – and that means wasted power, space and cooling (which costs more than the equipment itself).

PPP Show 38 – Comparing Data Centre Fabrics from Juniper, Brocade and Cisco

Kurt Bales has a customer who wants to buy a new Data Centre Network and the three main networking vendors (Juniper, Cisco & Brocade) have pitched at him and the customer. Kurt then contacted the Pushers and said “This would make a great podcast to talk about how it looks, works and the reality of the so-called “Data Centre Fabric networks, plus I’ve got some questions that I’d like to get some second opinions.”

So we rounded up Ivan from IOS Hints and Greg from EtherealMind to record a fast, furious and focussed look at the state of play with the three data centre fabrics today. Lots of speculation, wild guesses and deep diving followed. I learned heaps.

QFabric – What excites me!

I was intrigued and excited about the Junipers announcement last week of QFabric. I was vaguely aware of TRILL and Cisco implementation (Fabric Path), but came to the table (so to speak) with no pre-conceptions of what I might expect.   SCI-FI – Is this just me? Is the Q in QFabric taken from sci-fi […]