Network Design, Analysis, Review.
I wrote a white paper for Nuage Networks that is the first Packet Pushers White Paper. Nuage Networks have announced their version of SDN and I think it’s solid vision of what Software Defined Networking will become over the next couple of years – tunnel fabrics, software network agents in the server with load balancing and routing capabilities and controller/application software that can manage multiple data centres and their WAN networks.
Jump in and take a read.
i’ve writer about OpenCompute hardware standards a few times. Today has seen a few announcements that make me think networking could be about to change significantly. In this post on Gigaom, Rackspace is planning to build their own servers based on OpenCompute standard: Rackspace is contracting with Wistron and Quanta, two server manufacturers that also [...]
I was going to call this article “Ethernet Switches for Virtualisation Engineers” but, really, everyone should have some understanding of the internals of an Ethernet switch. But particularly I want to focus on how multicast and broadcasts are handled in a high speed, low latency environment like a Data Centre Network.
It’s vital to understand that latency is critical to your application performance. It is common for a single transaction to take hundreds of round trips so a small increase in latency on each round trip has a large impact on the perceived performance. The client will send a chunk of data and wait for acknowledgement. Even setting up the TCP connection takes a few round trip – remember that TCP sessions are setup, and each data transfer is confirmed.
A modern network switch will have latency around 10 microseconds. The Cisco Nexus 7000 is about 8 microseconds & Brocade VDX 8770 claims less than 4 microseconds. There are many reasons why a switch can be faster or slower but I’ll look at a specific example
Remember, the latency interval is the time taken to receive a packet, decode the address, lookup the forwarding table, switch the packet (and copy it if needed) and transmit out of an Ethernet interface. That’s really fast processing. How does an Ethernet switch do this ?
Network Engineers have to manage a lot of information. Products, technologies, textbooks, study notes and research material as well as new protocols and features. Just simple tasks like keeping product manuals handy for 40 or 50 products is a real problem. How do you keep the information organised, referenced, accessible and useful ? Your employer [...]
Network Engineers have to manage a lot of information. Products, technologies, textbooks, study notes and research material as well as new protocols and features. Just simple tasks like keeping product manuals handy for 40 or 50 products is a real problem. How do you keep the information organised, referenced, accessible and useful ? Your employer [...]
Network Engineers have to manage a lot of information. Products, technologies, textbooks, study notes and research material as well as new protocols and features. Just simple tasks like keeping product manuals handy for 40 or 50 products is a real problem. How do you keep the information organised, referenced, accessible and useful ?
This three part screencast is about how I manage all the “inputs” so I don’t feel lost in information after many, many people asked.
I think the writer is Timothy Dennehey, but this looks like a “keeper” for the times when you get involved with a high density WiFi design A project that has been consuming a lot of my time these days is how to deploy high density Wi-Fi in indoor and outdoor arenas and other high capacity [...]
Have been receiving email with questions on OpenFlow/SDN and looking for a definition blog post that explains how East/West and North/South LAN design can work with Northbound/Southbound APIs
There is an old saying “A man with his eyes fixed on Heaven doesn’t see where he is going”. It’s an almost perfect description of how the major vendors are bringing Software Defined Networking to the market.
The consistent message from all the vendors and especially the Cisco, Juniper and Brocade is that there are “no use cases for SDN”. In the last three months, this has been a constantly repeated statement both publicly and privately. This beggars belief that vendors can’t see immediate needs that deliver long term gains.
I suspect that the root of this problem is the big companies want to solve big problems. And by solving big problems they figure that they can make big revenue. Alright, I get that. It’s understandable that large organisations need a constant revenue stream to feed the insatiable maws of their shareholders. However, the vendors re also missing the most real and immediate problem of networking today. Simply, Networking is too hard.
Vendors haven’t developed tools that keep the complexity of networking under control. Complexity can be reduced to this: “I don’t have big problems, I have lots of small problems.” You can have debates about addressing complexity and how to attack it, but it nearly always boils down to this: start small.
You can deploy some modern firewalls in Layer 2 mode such that they are transpart
You want to write blog posts but you don't know how. This is the eBook for you. My personal tips on how to get the writing done and published
EtherealMind hosts a podcast on Data Networking where we talk nerdy about technology, recent events, conduct interviews and more. We look at technology, the industry and our daily work lives every week.
Our motto: Too Much Networking Would Never Be Enough..
