Worth Reading: A Primer on Communication Fundamentals
Dip Singh published an excellent primer on communication fundamentals including:
- Waves: frequency, amplitude, wavelength, phase
- Composite signals, frequency domain and Fourier transform
- Bandwidth, fundamental and harmonic frequency
- Decibels in a nutshell
- Transmission impairments: attenuation, distortion, noise
- Principles of modern communications: Nyquist theorem, Shannon’s law, bit and baud rate
- Line encoding techniques, quadrature methods (including QPSK and QAM)
Even if you don’t care about layer-1 technologies you MUST read it to get at least a basic appreciation of why stuff you’re using to read this blog post works.
Worth Reading: A Primer on Communication Fundamentals
Dip Singh published an excellent primer on communication fundamentals including:
- Waves: frequency, amplitude, wavelength, phase
- Composite signals, frequency domain and Fourier transform
- Bandwidth, fundamental and harmonic frequency
- Decibels in a nutshell
- Transmission impairments: attenuation, distortion, noise
- Principles of modern communications: Nyquist theorem, Shannon’s law, bit and baud rate
- Line encoding techniques, quadrature methods (including QPSK and QAM)
Even if you don’t care about layer-1 technologies you MUST read it to get at least a basic appreciation of why stuff you’re using to read this blog post works.
Observations on Seven Years of Maintaining Open Source
June 27th marks the seventh anniversary of NetBox, a one-time hobby project which quickly took off and today largely consumes my life. What began as a proof-of-concept solution for the network engineering team at DigitalOcean is now perhaps the most widely deployed network source of truth in the world.
This feels like an opportune time to reflect on some lessons I've learned along the way, with the hope of offering mixed encouragement and caution to those considering a similar path. And as I've felt the urge to pick up blogging again, this post will also serve to share what I've been up to recently.
Most articles about open source in general are boring. Reading about licenses and software governance feels like a punishment. Keenly aware of this fact, I'll do my best to navigate around the theory and stick with observations that are of practical use to the aspiring open source maintainer.
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Heavy Networking 686: Juniper Cloud-Native Contrail Networking CN2 (Sponsored)
Today we’re going deep on software-defined networking for containers and OpenStack with sponsor Juniper Networks. Juniper has revamped its approach to secure networking for telcos and telco cloud-delivered services with Juniper’s Cloud-Native Contrail Networking or CN2 software. CN2 lets you automate the creation of network connections for containers and for virtual machines while also providing routing, security, segmentation and isolation of workloads. Our guest and guide into the guts of Cloud-Native Contrail Networking, hereafter referred to as CN2, is Nick Davey. Nick is Director of Product Management for SDN and Telco Cloud technologies.Heavy Networking 686: Juniper Cloud-Native Contrail Networking CN2 (Sponsored)
Today we’re going deep on software-defined networking for containers and OpenStack with sponsor Juniper Networks. Juniper has revamped its approach to secure networking for telcos and telco cloud-delivered services with Juniper’s Cloud-Native Contrail Networking or CN2 software. CN2 lets you automate the creation of network connections for containers and for virtual machines while also providing routing, security, segmentation and isolation of workloads. Our guest and guide into the guts of Cloud-Native Contrail Networking, hereafter referred to as CN2, is Nick Davey. Nick is Director of Product Management for SDN and Telco Cloud technologies.
The post Heavy Networking 686: Juniper Cloud-Native Contrail Networking CN2 (Sponsored) appeared first on Packet Pushers.
The Big Clouds Get First Dibs On AMD “Genoa” Chips
The expanded lineup of AMD’s 4th generation “Genoa” Epyc server chips – built atop “Zen 4” core and some with the chip maker’s L3-boosting 3D V-Cache – unveiled at a high-profile event in San Francisco this week is quickly making its way into the cloud. …
The Big Clouds Get First Dibs On AMD “Genoa” Chips was written by Jeffrey Burt at The Next Platform.
Hedge 182: The Decentralized Internet Infrastructure Research Group
The Internet has become very centralized in the last five to ten years, causing a lot of concern among among many in the Internet community. While we cannot turn back the clock, we can try to chart a path forward to reduce the tendency towards centralization. Join Dirk Dirk Kutscher, Lixia Zhang, Alvaro Retana, Tom Ammon, and Russ White on this episode of the Hedge as we discuss the work the Distributed Internet Research Group (DINRG) is doing to create a more decentralized Internet.
Don’t Let Age Mothball Your IT Career
Age is only a number. Don't let a high number cancel your career.Kubernetes Unpacked Episode 028: K8s Consulting-A Journey Of Discovery And Burnout
In this episode of the Kubernetes Unpacked podcast, co-hosts Michael Levan and Kristina Devochko interview David Flanagan, a Kubernetes consultant, about his experience running his own consultancy and specializing in a specific technology or platform. David shares his career journey and emphasizes the importance of authenticity, credibility, and long-term thinking in the world of technology consulting. The conversation also touches on the use of AI in Kubernetes, the challenges and rewards of being an independent consultant, and the importance of setting personal boundaries and constraints early on to prevent burnout. David also shares his insights into some of the quirks of Kubernetes.Kubernetes Unpacked Episode 028: K8s Consulting-A Journey Of Discovery And Burnout
In this episode of the Kubernetes Unpacked podcast, co-hosts Michael Levan and Kristina Devochko interview David Flanagan, a Kubernetes consultant, about his experience running his own consultancy and specializing in a specific technology or platform. David shares his career journey and emphasizes the importance of authenticity, credibility, and long-term thinking in the world of technology consulting. The conversation also touches on the use of AI in Kubernetes, the challenges and rewards of being an independent consultant, and the importance of setting personal boundaries and constraints early on to prevent burnout. David also shares his insights into some of the quirks of Kubernetes.
The post Kubernetes Unpacked Episode 028: K8s Consulting-A Journey Of Discovery And Burnout appeared first on Packet Pushers.
Case study: Calico enables HanseMerkur to reduce infrastructure overhead and achieve ISO 27001 compliance
Established in 1875, HanseMerkur is one of the oldest private health insurance companies in Germany, with customers across Europe. The company ran multi-tenant clusters on premises with Kubespray, with around 150 internal software developers as users. As the company must handle personal information and confidential data, it adheres to ISO 27001, the German equivalent of SOC 2, as per industry standards.
The company’s legacy platform was based on Kubernetes 1.11 (released in 2018), and no updates could be made without completely rebuilding the platform. In fact, the company needed to build new clusters for each new product and also rebuild the existing clusters in order to update Kubernetes versions.
HanseMerkur’s clusters were virtualized on top of a legacy hypervisor, and resources had to be sized for traditional deployment on a per tenant basis. There were a number of issues with this set up, including high overhead, low flexibility, and over-consumption of hardware. As a result, the company’s platform team wanted to go bare metal and consolidate the company’s entire infrastructure into one place.
In an exclusive interview, HanseMerkur details how Calico helped solve the challenges of their consolidation project and helped the company enforce the security and observability capabilities Continue reading
IPv6 Buzz 128: Cisco Enabling IPv6 In The Enterprise (Sponsored)
There's only going to be one episode 128 of IPv6 Buzz, and this is it. In this Cisco Country Digital Acceleration Program sponsored episode, co-hosts Ed Horley and Scott Hogg talk with Pradeep Kathail and Mark Townsley. Pradeep is the CTO of Enterprise Networking, and Mark Townsley is a Cisco Fellow in the Meraki Business Unit.IPv6 Buzz 128: Cisco Enabling IPv6 In The Enterprise (Sponsored)
There's only going to be one episode 128 of IPv6 Buzz, and this is it. In this Cisco Country Digital Acceleration Program sponsored episode, co-hosts Ed Horley and Scott Hogg talk with Pradeep Kathail and Mark Townsley. Pradeep is the CTO of Enterprise Networking, and Mark Townsley is a Cisco Fellow in the Meraki Business Unit.
The post IPv6 Buzz 128: Cisco Enabling IPv6 In The Enterprise (Sponsored) appeared first on Packet Pushers.
Secure egress access with DNS Policy and NetworkSets
One of the common concerns about migrating applications to Kubernetes is the control over the network traffic egressing your environment. Due to its highly dynamic architecture, Kubernetes will not tie a specific IP address to an application by default. Instead, it will lease a different IP address from an IP pool whenever the application restarts.
Suppose you use traditional network security appliances like firewalls to provide network perimeter protection. In this case, enforcing the least privilege principle by allowing only a specific application to egress traffic outside your network is impossible. In a firewall configuration, you must specify the application IP address when creating the egress rule. As it is impossible to determine the application IP address, you must allow access to the nodes’ IP addresses if you are using overlay, or to the entire IP range you use in the IP pool. By doing this, you will also allow access to any application running on that Kubernetes cluster.
Learn more: Kubernetes Network Policy: Code Example and Best Practices
A better option would be to use Kubernetes network policies, which enable you to create rules to allow ingress and egress traffic to a workload based on the labels applied to Continue reading