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Category Archives for "Networking"

A Name Resolver for the Distributed Web

A Name Resolver for the Distributed Web
A Name Resolver for the Distributed Web

The Domain Name System (DNS) matches names to resources. Instead of typing 104.18.26.46 to access the Cloudflare Blog, you type blog.cloudflare.com and, using DNS, the domain name resolves to 104.18.26.46, the Cloudflare Blog IP address.

Similarly, distributed systems such as Ethereum and IPFS rely on a naming system to be usable. DNS could be used, but its resolvers’ attributes run contrary to properties valued in distributed Web (dWeb) systems. Namely, dWeb resolvers ideally provide (i) locally verifiable data, (ii) built-in history, and (iii) have no single trust anchor.

At Cloudflare Research, we have been exploring alternative ways to resolve queries to responses that align with these attributes. We are proud to announce a new resolver for the Distributed Web, where IPFS content indexed by the Ethereum Name Service (ENS) can be accessed.

To discover how it has been built, and how you can use it today, read on.

Welcome to the Distributed Web

IPFS and its addressing system

The InterPlanetary FileSystem (IPFS) is a peer-to-peer network for storing content on a distributed file system. It is composed of a set of computers called nodes that store and relay content using a common Continue reading

Developing NetBox Plugin – Part 3 – Adding search panel

Welcome to part 3 of my tutorial walking you through process of developing NetBox plugin. In part 2 we added basic web UI views to our BgpPeering plugin. In this post we'll add search panel to list view to allow us to search/filter Bgp Peering objects.

Developing NetBox Plugin tutorial series

Contents

Introduction

List view we created for displaying all Bgp Peering objects in one place is very useful. However it will become difficult to find items of interest once we have more than 30-50 objects. For that purpose we should add means of filtering objects to the ones that meet certain criteria.

Other objects in NetBox already have filtering functionality and use search panel located to the right of object tables. Continue reading

Imperative and Declarative API: Another Pile of Marketing Deja-Moo

Looks like some vendor marketers (you know, the same group of people who brought us the switching/routing/bridging stupidity) felt the need to go beyond the usual SDN and intent-based hype and started misusing the imperative versus declarative concepts. Unfortunately some networking engineers fell for the ploy; here’s a typical feedback along these lines I got from one of my readers:

I am frustrated by most people’s shallow understanding API’s, especially the differences between declarative (“what”) and imperative (“how”) API’s, and how that impacts one’s operations. Declarative APIs are the key pillar of what many vendors call “policy” or “intent-based” networking.

Let’s try to unravel that.

Imperative and Declarative API: Another Pile of Marketing Deja-Moo

Looks like some vendor marketers (you know, the same group of people who brought us the switching/routing/bridging stupidity) felt the need to go beyond the usual SDN and intent-based hype and started misusing the imperative versus declarative concepts. Unfortunately some networking engineers fell for the ploy; here’s a typical feedback along these lines I got from one of my readers:

I am frustrated by most people’s shallow understanding API’s, especially the differences between declarative (“what”) and imperative (“how”) API’s, and how that impacts one’s operations. Declarative APIs are the key pillar of what many vendors call “policy” or “intent-based” networking.

Let’s try to unravel that.

Finding Ways of Teaching

Some days ago I tweeted about that when you are trying to master a topic, you should both find different sources to learn from, as well as different mediums, such as reading, listening, watching videos, but also not to forget labbing. I also wrote that teaching someone else is a great way of learning and retaining information yourself. You might be familiar with the saying that “You remember 10% of what we read, 20% of what we hear, 30% of what we see, 80% of what we personally experience, and 95% of what we teach others”. How truthful this statement is, is up for debate, but I think we can all agree that you will recall more of what you have learned if you are teaching the topic to someone, as opposed to just reading about something.

How do you find a place to teach, though?

Thankfully, there are a lot of options today to teach, even some that may not seem obvious at first. Let’s go through a few of them.

Blogging – As you’re reading this blog, hopefully you are learning something. It may not seem like teaching, considering that it’s not a realtime event, but it is Continue reading

Calico & Calico Enterprise: Now Available as AWS Quick Starts

As an AWS Advanced Technology Partner with AWS Containers Competency, Tigera is thrilled to announce that Calico and Calico Enterprise are both now available as AWS Quick Starts. If you’re unfamiliar with the concept, an AWS Quick Start is a ready-to-use accelerator that fast-tracks deployments of key cloud workloads for AWS customers. Described as “gold-standard deployments in the AWS Cloud”, Quick Starts are designed to reduce hundreds of manual procedures into an automated, workflow-based reference deployment.

With Calico network policy enforcement, you can implement network segmentation and tenant isolation, which is especially useful when you want to create separate environments for development, staging, and production. Calico Enterprise builds on top of open source Calico to provide additional higher-level features and capabilities, and integrates with your existing AWS tools including security groups, Amazon CloudWatch, and AWS Security Hub so you can leverage existing processes and workflows in your EKS or Kubernetes infrastructure.

Everything you need to take advantage of Calico and Calico Enterprise in these Quick Starts is installed and configured in your Amazon Elastic Kubernetes (Amazon EKS) cluster, enabling you to take advantage of a rich set of Kubernetes security, observability, and networking features that Tigera provides in these Continue reading

Ansible Network Resource Modules: Deep Dive on Return Values

The Red Hat Ansible Network Automation engineering team is continually adding new resource modules to its supported network platforms.  Ansible Network Automation resource modules are opinionated network modules that make network automation easier to manage and more consistent for those automating various network platforms in production. The goal for resource modules is to avoid creating and maintaining overly complex jinja2 templates for rendering and pushing network configuration, as well as having to maintain complex fact gathering and parsing methodologies.  For this blog post, we will cover standard return values that are the same across all supported network platforms (e.g. Arista EOS, Cisco IOS, NXOS, IOS-XR, and Juniper Junos) and all resource modules. 

Before we get started, I wanted to call out three previous blog posts covering resource modules. If you are unfamiliar with resource modules, check any of these out:

Technologies that Didn’t: ARCnet

In the late 1980’s, I worked at a small value added reseller (VAR) around New York City. While we deployed a lot of thinnet (RG58 coax based Ethernet for those who don’t know what thinnet is), we also had multiple customers who used ARCnet.

Back in the early days of personal computers like the Amiga 500, the 8086 based XT (running at 4.77MHz), and the 8088 based AT, all networks were effectively wide area, used to connect PDP-11’s and similar gear between college campuses and research institutions. ARCnet was developed in 1976, and became popular in the early 1980’s, because it was, at that point, the only available local area networking solution for personal computers.

ARCnet was not an accidental choice in the networks I supported at the time. While thinnet was widely available, it required running coax cable. The only twisted pair Ethernet standard available at the time required new cables to be run through buildings, which could often be an expensive proposition. For instance, one of the places that relied heavily on ARCnet was a legal office in a small town in north-central New Jersey. This law office had started out in an older home over a Continue reading

Master Class: DC Fabrics

I’m teaching another master class over at Juniper on the 13th at 9AM PT:

Spine-and-leaf fabric is the “new standard,” but how much do you know about this topology, its origins, and its properties? This session will consider the history of the Clos, explain the butterfly and Benes, look at why a fabric is a fabric and why “normal networks” are not, and cover some key design considerations when building a fabric.

You can register here.

Cloudflare Radar’s 2020 Year In Review

Cloudflare Radar's 2020 Year In Review
Cloudflare Radar's 2020 Year In Review

Throughout 2020, we tracked changing Internet trends as the SARS-Cov-2 pandemic forced us all to change the way we were living, working, exercising and learning. In early April, we created a dedicated website https://builtforthis.net/ that showed some of the ways in which Internet use had changed, suddenly, because of the crisis.

On that website, we showed how traffic patterns had changed; for example, where people accessed the Internet from, how usage had jumped up dramatically, and how Internet attacks continued unabated and ultimately increased.

Today we are launching a dedicated Year In Review page with interactive maps and charts you can use to explore what changed on the Internet in 2020. Year In Review is part of Cloudflare Radar. We launched Radar in September 2020 to give anyone access to Internet use and abuse trends that Cloudflare normally had reserved only for employees.

Where people accessed the Internet

To get a sense for the Year In Review, let’s zoom in on London (you can do the same with any city from a long list of locations that we’ve analyzed). Here’s a map showing the change in Internet use comparing April (post-lockdown) and February (pre-lockdown). This map compares working hours Continue reading

The Attention Economy And The IT Talent Dearth

In IT operations, finding talent is difficult. For years, there has been a shortage of folks who are capable of maintaining complex infrastructure. To be sure, some of this is geographical. And certainly, the rate of technology change makes it difficult to find people with specific product skills. Hard to find a Kubernetes expert with ten years of experience. ?

But I suspect there’s a couple of other things going on that, when combined, make the talent dearth even worse.

The Brutality Of Complexity

When I was studying for Novell Netware 3 (before directory services) certifications decades ago, there was a lot to know. Networking with IPX. Architecture of x86 servers. NLMs. Storage strategies. Mail systems. Whatever else was in those red books many of us had on our shelves.

Pre-AD Microsoft certifications were similarly challenging. Domain controllers. Backup domain controllers. File & print systems. User permissions and design strategies. The GINA. Networking with IP, IPX, and NetBEUI. Mail systems. IIS. So much more.

That was before the addition of directory services to Novell and Microsoft operating systems. Directory services changed the game for file, print, email, and more back in the day, and it put a major burden on IT Continue reading

Build Resilient, Secure Microservices with Microsegmentation

About 10 to 12 years ago, the world of software experienced a shift in the architectural aspects of enterprise applications. Architects and software builders started moving away from the giant, tightly coupled, monolithic applications deployed in the private data centers to a more microservices-oriented architecture hosted in public cloud infrastructure. The inherent distributed nature of microservices is a new security challenge in the public cloud. Over the last decade, despite the growing adoption of microservices-oriented architecture for building scalable, autonomous, and robust enterprise applications, organizations often struggle to protect against this new attack surface in the cloud compared to the traditional data centers. It includes concerns around multitenancy and lack of visibility and control over the infrastructure, as well as the operational environment. This architectural shift makes meeting security goals harder, especially with the paramount emphasis placed on faster container-based deployments. The purpose of this article is to understand what microsegmentation is and how it can empower software architects, DevOps engineers, and IT security architects to build secure and resilient microservices. Specifically, I’ll discuss the network security challenges associated with the popular container orchestration mechanism Kubernetes, and I will illustrate the value of microsegmentation to prevent lateral movement when a Continue reading

Interconnecting GNS3 Virtual Machines – Video

GNS3 co-founder and developer Jeremy Grossman and networking instructor David Bombal talk with Ethan Banks about how separate GNS3 VMs communicate. You can listen to the full episode, “Heavy Networking 556: The State Of GNS3 For Network Labs,” by clicking this link. Heavy Networking is part of the Packet Pushers network of technical podcasts, including […]

The post Interconnecting GNS3 Virtual Machines – Video appeared first on Packet Pushers.

Automation Win: Chatops-Based Security

It’s amazing how quickly you can deploy new functionality once you have a solid foundation in place. In his latest blog post Adrian Giacometti described how he implemented a security solution that allows network operators to block source IP addresses (identified by security tools) across dozens of firewalls using a bot listening to a Slack channel.

Would you be surprised if I told you we covered similar topics in our automation course? ?

Automation Win: Chatops-Based Security

It’s amazing how quickly you can deploy new functionality once you have a solid foundation in place. In his latest blog post Adrian Giacometti described how he implemented a security solution that allows network operators to block source IP addresses (identified by security tools) across dozens of firewalls using a bot listening to a Slack channel.

Would you be surprised if I told you we covered similar topics in our automation course? 😇

Automating responses to scripts on Linux using expect and autoexpect

The Linux expect command takes script writing to an entirely new level. Instead of automating processes, it automates running and responding to other scripts. In other words, you can write a script that asks how you are and then create an expect script that both runs it and tells it that you're ok.Here's the bash script:#!/bin/bash echo "How are you doing?" read ans [Get regularly scheduled insights by signing up for Network World newsletters.] Here's the expect script that provides the response to the query:#!/usr/bin/expect set timeout -1 spawn ./ask # ask is name of script to be run expect "How are you doing?\r" send -- "ok\r" expect eof When you run the script, you should see this:To read this article in full, please click here

Network Break 315: Pluralsight Sold For $3.5 Billion; Dent NOS Hitchhikes To The Edge

This week's Network Break discusses the jaw-dropping $3.5 billion purchase of Pluralsight; welcomes a new network OS to life, the universe, and everything; debates whether ICANN was cautious or tardy in implementing DNSSEC for gTLD name servers, catches up on the SolarWinds hack, and more tech conversation.

The post Network Break 315: Pluralsight Sold For $3.5 Billion; Dent NOS Hitchhikes To The Edge appeared first on Packet Pushers.