Was reading through some documentation as noticed that the Nexus 5500 series has some unusual behaviours for Store and Forward. I made myself notes about the functional modes. Cut-Through vs Store and Forward In cut-through mode of operation a switch will start transmitting a frame before the frame has been completely received and this is the […]
Juniper QFabric is a new approach to Ethernet Switch Fabrics. When it was announced last year,it was noted that the underlying physical design is a completely different approach to building Switch Fabrics. Here I’m taking a loosely research based approach to understand how Juniper QFabric is different from all other approaches to the problem, and also a look at some of the challenges ahead.
Short Answer is “It depends, but usually yes.” Long answer follows with a discussion of launch power, receiver sensitivity, and cable losses.
I’m responding to Brad Hedlund’s post “On optimizing traffic for network virtualization” where he seems to missed a key point. It’s about cost of ownership in terms of ability to troubleshoot.
I’ve been doing some research into Ethernet and the use of Jumbo frames for some content I’ve been writing and come across something interesting. The documents state that Jumbo frames can only be used on Full Duplex Ethernet connections.
A couple of weeks back I posted this article comparing pricing and features on Cisco Fabric Ethernet Transceivers as a low cost option compared to 10GbaseSR SFP+ optics in when building 10GbE networks – Cisco Nexus 5000 / 2000 Pricing Bundles and Fabric Extension Transceivers (FETs) vs 10GbaseSR SFPs.
Define “Ethernet Fabric”
A lesser known standard is Backplane Ethernet. I wasn’t aware of it until I was researching Notes on Cables and Connectors for 40 and 100 Gigabit Ethernet. I spent some time over the weekend scratching an itch to have a look at it and why it exists.These are scrach notes, and observations from a research session and not intended to a canonical investigation. Interesting though because it’s is valuable to understand that many network products are functionally all the same – only the software and the people are different.
Collection of useful, relevant or inane places on the the Internets for 3 Jan 11: