Have you ever looked at your wide area network and wondered … what would the traffic flows look like if this link or that router failed? Traffic modeling of this kind is widely available in commercial tools, which means it’s been hard to play with these kinds of tools, learn how they work, and understand how they can be effective. There is, however, an open source alternative—pyNTM. While this tool won’t replace a commercial tool, it can give you “enough to go on” for many network operators, and give you the experience and understanding needed to justify springing for a commercial product.
SD-WAN vendors offer a variety of mechanisms to connect end users to cloud applications while incorporating policy and performance requirements. Day Two Cloud co-host Ethan Banks interviewed many of these vendors to understand the architectural nitty-gritty of different approaches. In this episode, he shares the fruits of his research.
The post Day Two Cloud 065: Building Your Cloud On-Ramp With SD-WAN appeared first on Packet Pushers.
Stop futzing with one device and think about the system.
As the scale of Cloudflare’s edge network has grown, we sometimes reach the limits of parts of our architecture. About two years ago we realized that our existing solution for spreading load within our data centers could no longer meet our needs. We embarked on a project to deploy a Layer 4 Load Balancer, internally called Unimog, to improve the reliability and operational efficiency of our edge network. Unimog has now been deployed in production for over a year.
This post explains the problems Unimog solves and how it works. Unimog builds on techniques used in other Layer 4 Load Balancers, but there are many details of its implementation that are tailored to the needs of our edge network.
Cloudflare operates an anycast network, meaning that our data centers in 200+ cities around the world serve the same IP addresses. For example, our own cloudflare.com website uses Cloudflare services, and one of its IP addresses is 104.17.175.85. All of our data centers will accept connections to that address and respond to HTTP requests. By the magic of Internet routing, when you visit cloudflare.com and your Continue reading
This story, like another in the past, started as an eBay purchase that I wo
We did a number of Software Gone Wild podcasts trying to figure out whether smart NICs address a real need or whether it’s just another vendor attempt to explore all potential markets. As expected, we got opposing views from Luke Gorrie claiming a NIC should be as simple as possible to Silvano Gai explaining how dedicated hardware performs the same operations at lower cost, lower power consumption and way higher speeds.
In theory, there’s no doubt that Silvano is right. Just look at how expensive some router line cards are, and try to figure out how much it would cost to get 25.6 Tbps of forwarding performance that we’ll get in a single ASIC (Tomahawk-4) in software (assuming ~10 Gbps per CPU core). High-speed core packet forwarding has to be done in dedicated hardware.
The Internet has been revolutionary for human progress. Bit by bit, byte by byte, it has come to underpin modern life. For those of us online today it is hard to imagine (or remember) a world where the Internet was not the fabric of our social lives, education, entertainment, innovation, and culture. But what makes the Internet such a success, and how can we ensure its future? What takes a “network of networks” and makes it the Internet? We’ve launched the Internet Way of Networking’s Internet Impact Assessment Toolkit (IIAT) to to help answer that question.
The current pandemic has showed us both the value and the opportunities the Internet holds. For societies to pivot to a reality where most of our lives became digital overnight is a true testament to the possibilities that are inherent in the Internet.
But while the Internet has proved its resilience under the weight of an online society, it is easy to forget that its fundamental premise is not about cables and computers, but about collaboratively interconnecting independent networks to a greater whole. Because what fundamentally makes up the Internet, and what it could grow to become in the future, is rooted in its Continue reading
Back from this post http://r2079.com/2020/03/17/telnyx-api-p-sms-and-aws-iot-saves-my-plants-every-single-time/, I did see that using Telnyx and Aws MQTT did indicate the moisture. All good, so why drag this topic ?
Links reference :
https://www.espressif.com/en/products/socs/esp32 – microcontroller used in the project
https://vruzend.com/ – lithium ion 18650 batteries
https://micropython.org/ – micropython
http://telnyx.com/ – Telecom provider
https://aws.amazon.com/ – Cloud provider
Well, there are multiple aspects to the design itself
From time immemorial, humor has served to capture truth. This is no different in the world of computer networks. A notable example of using humor to capture truth is the April 1 RFC series published by the IETF. RFC1925, The Twelve Networking Truths, will serve as our guide.
According to RFC1925, the first fundamental truth of networking is: it has to work. While this might seem to be overly simplistic, it has proven—over the years—to be much more difficult to implement in real life than it looks like in a slide deck. Those with extensive experience with failures, however, can often make a better guess at what is possible to make work than those without such experience. The good news, however, is the experience of failure can be shared, especially through self-deprecating humor.
Consider RFC748, which is the first April First RFC published by the IETF, the TELNET RANDOMLY-LOSE Option. This RFC describes a set of additional signals in the TELNET protocol (for those too young to remember, TELNET is what people used to communicate with hosts before SSH and web browsers!) that instruct the server not to provide random losses through such things as “system crashes, lost data, Continue reading