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Category Archives for "Networking"

Using the Linux arping command to ping local systems

The arping command is one of the lesser known commands that works much like the ping command.The name stands for “arp ping” and it’s a tool that allows you to perform limited ping requests in that it collects information on local systems only. The reason for this is that it uses a Layer 2 network protocol and is, therefore, non-routable. The arping command is used for discovering and probing hosts on your local network.[Get regularly scheduled insights by signing up for Network World newsletters.] If arping isn’t installed on your system, you should be able take care of that with one of these commands:To read this article in full, please click here

Developing Enterprise Software with Scalability Top of Mind

Yasser Ganjisaffar Yasser Ganjisaffar is the VP of Engineering at Forward Networks, overseeing all the company’s engineering efforts. He joined Forward Networks in 2014 as an early employee and led the team that scaled the computation core of Forward Enterprise product by 1000x in five years. Prior to that, he built large-scale search infrastructures in Facebook and Microsoft. He holds a Computer Science Ph.D. in the information retrieval domain. Developing enterprise software is far from simple. Designing a platform to serve hundreds of thousands of users, devices, or data streams (sometimes all at once) is a Herculean task. But that doesn’t mean that it’s impossible to approach the design methodology in a way that encourages scalability in the future. Scalability is one of the most important considerations in making a new software solution. Without it, the software cannot support user growth without crippling the user experience, and similarly inhibiting sales. Making a scalable software platform is challenging simply because it’s near impossible to know what factors, options and problems the vendor needs to take into consideration beforehand, requiring companies to instead iterate along the way. That was the issue

Mizar: Scalable Multitenant Networking with XDP on Kubernetes

Mizar is an open source project providing cloud networking to run virtual machines, containers, and other compute workloads. We built Mizar from the ground up with large scale and high performance in mind. Built in the same way as distributed systems in the cloud, Mizar utilizes XDP (eXpress Data Path) and Kubernetes to allow for the efficient creation of multitenant overlay networks with massive amounts of endpoints. Each of these technologies brings valuable perks that enable Mizar to achieve its goals. With XDP, Mizar is able to: Skip unnecessary stages of the network stack whenever possible and transit packet processing to smart NICs. Efficiently use kernel packet processing constructs without being locked into a specific processor architecture. Produce very small packet processing programs (<4KB). With Kubernetes, Mizar is able to: Efficiently program the underlying core XDP programs. Manage the lifecycle of its abstractions via CRDs. Have a scalable and distributed management plane. Deploy its core components and modules across all specified hosts. Mizar’s Goals and Continue reading

Upcoming Webinar: How Routers Really Work

Just a gentle reminder that on Monday (just a few days from now) I’m teaching a three hour webinar over at Safari Books on How Routers Really Work. From the course description—

This training will peer into the internal components of a router, starting with an explanation of how a router switches packets. This walk through of a switching path, in turn, will be used as a foundation for explaining the components of a router, including the various tables used to build forwarding tables and the software components used to build these tables.

Register here if you’re interested.

TTL255 finalist of Cisco 2020 IT Blog Awards

I'm excited to announce that TTL255.com is one of the finalists in the Most Educational category of the 2020 IT Blog Awards, hosted by Cisco.

Over the years I learned great deal from blogs and videos created by community members. At one point I realized that I also might have something to offer and started this blog to give back to community hoping to teach and inspire others.

Creating valuable technical content takes a lot of work and time commitment. After years of posting here I appreciate even more all content makers out there that often don't ask for anything in return.

This year I decided to submit TTL255.com to 2020 IT Blog Awards hoping to reach more people and see where that takes me.

If you find my content valuable and worth your time, please consider voting for TTL255.com by following the below link:

https://www.ciscofeedback.vovici.com/se/705E3ECD2A8D7180

ITBlogAwards_2020_Badge-Finalist-MostEducational

You can find me in the Most Educational category:

blog-awards-entry

While you there have a look at other amazing blog posts. Some of them might inspire you, some will teach you something new. All come from members of community that put themselves out there to share their knowledge with Continue reading

2020 IT Blog Awards finalist!

2020 IT Blog Awards finalist

I have the honor of having my blog selected as a finalist in the Most Educational category of the 2020 IT Blog Awards, hosted by Cisco. It is an honor and a great joy for me to be selected, for the third consecutive year, alongside other high-level bloggers who all have very deep technical knowledge! I hope you enjoy my articles as much as I enjoy writing and sharing them. I know I could write more, but I try to put quality ahead of quantity.   Please click here to vote…

The post 2020 IT Blog Awards finalist! appeared first on AboutNetworks.net.

International Community Joins Indian Policy and Cybersecurity Experts in Warning about the Dangers of Traceability

A growing group of international and local cybersecurity and policy experts are weighing in on proposed changes to Indian regulations that could jeopardize the safety of billions worldwide. By seeking to restrict WhatsApp and other popular messaging apps’ use of end-to-end encryption, the proposed policies pose a major threat to cybersecurity in India.

In Traceability and Cybersecurity, over 50 cybersecurity experts in Europe, North and Latin America, Africa, and the Asia-Pacific region agreed that amendments to the Information Technology (Intermediaries Guidelines) Rules under the Indian Information Technology Act proposed by the Indian Ministry of Electronics and Information Technology (MeiTY) will create many more problems than it seeks to solve.

Produced as a result of a global technical experts meeting series organized by the Internet Society in partnership with Medianama, the report notes that MeiTY’s proposal ignores sound advice: requiring intermediaries such as WhatsApp to enable the traceability of the content and data they handle is a major threat not only to the safety of users, but to India’s national security.

The report stresses that traceability would mean enabling third-party access to private communications, a move that undermines the end-to-end encryption that users everywhere, including government entities, rely on to Continue reading

Introducing Cloudflare Pages: the best way to build JAMstack websites

Introducing Cloudflare Pages: the best way to build JAMstack websites
Introducing Cloudflare Pages: the best way to build JAMstack websites

Across multiple cultures around the world, this time of year is a time of celebration and sharing of gifts with the people we care the most about. In that spirit, we thought we'd take this time to give back to the developer community that has been so supportive of Cloudflare for the last 10 years.

Today, we’re excited to announce Cloudflare Pages: a fast, secure and free way to build and host your JAMstack sites.

Today, the path from an idea to a website is paved with good intentions

Websites are the way we express ourselves on the web. It doesn’t matter if you’re a hobbyist with a blog, or the largest of corporations with millions of customers — if you want to reach people outside the confines of 140 280 characters, the web is the place to be.

As a frontend developer, it’s your responsibility to bring this expression to life. And make no mistake — with so many frontend frameworks, tooling, and static site generators at your disposal — it’s a great time to be in your line of work.

That is, of course, right up until the point when you’re ready to show your work off Continue reading

Build Your Virtual Lab Faster with My Network Simulation Tools

I love my new Vagrant+Libvirt virtual lab environment – it creates virtual machines in parallel and builds labs much faster than my previous VirtualBox-based setup. Eight CPU cores and 32 GB of RAM in my Intel NUC don’t hurt either.

However, it’s still ridiculously boring to set up a new lab. Vagrantfiles describing the private networks I need for routing protocol focused network simulations are a mess to write, and it takes way too long to log into all the devices, configure common parameters, enable interfaces…

Build Your Virtual Lab Faster with netlab

I love my new Vagrant+Libvirt virtual lab environment – it creates virtual machines in parallel and builds labs much faster than my previous VirtualBox-based setup. Eight CPU cores and 32 GB of RAM in my Intel NUC don’t hurt either.

However, it’s still ridiculously boring to set up a new lab. Vagrantfiles describing the private networks I need for routing protocol focused network simulations are a mess to write, and it takes way too long to log into all the devices, configure common parameters, enable interfaces…

Flask web app tutorial for network engineers

Most network engineers don’t need to create web sites but they may, like me, want to convert their existing Python command-line programs into web apps so others can use them more easily. This tutorial presents the minimum you need to know about Python, Flask, and the Bootstrap CSS framework to create a practical web app that looks professional.

This tutorial covers a different type of use-case than is usually demonstrated in Flask tutorials aimed at beginners. It shows you how to create a web app that “wraps up” another Python program’s functionality.

I will show you how to use the Flask framework to build a web app that re-uses code from my Usermapper program and enables users to run it on a website, instead of installing and running it locally on their PC. You will create a “usermapper-as-a-service” application, served as a responsive web app that looks good on computer screens, tablets, and mobile phones.

I wrote this tutorial while I was learning Flask and developing my usermapper-web Flask application. It was written by a beginner, for other beginners. It walks through topics in the order in which I learned them. I hope you find this approach to be readable Continue reading

Automated, Simplified DNS Troubleshooting for Kubernetes: Only in Calico Enterprise

The Domain Name System (DNS) is a naming system for computers, services, or other resources connected to the Internet or a private network. DNS translates domain names to the numerical IP addresses needed for locating and identifying computer services and devices. For decades It’s been an essential component of the Internet. It’s an essential part of Kubernetes as well, and is used to determine how workloads connect to Kubernetes services as well as resources outside the cluster.

DNS also happens to be a common source of outages and issues in Kubernetes clusters. When applications are not working as expected, the root cause is often DNS-related. However, debugging and troubleshooting DNS issues in Kubernetes environments is not a trivial task given the limited amount of information Kubernetes provides for DNS queries.

Lacking the necessary visibility into the cluster to correlate a DNS query or reply with a specific workload, for example, you are left in the dark. Without Kubernetes context, you are unable to capture even the most fundamental information needed for troubleshooting, such as the type of DNS query (or reply) or the source of the query.

Figure: The DNS Dashboard from Tigera helps Kubernetes teams more quickly confirm or Continue reading

Tech Bytes: Accelerating Cloud Applications With Riverbed’s Cloud SteelHead (Sponsored)

Today's Tech Bytes is a customer story with sponsor Riverbed. It’s a tale of latency and its impact on network performance when moving applications to cloud. Our guests from Riverbed are Aly Walowski, whose title is roughly “Cloud Goddess” at Riverbed; and Jack Sweeney, Major Account Manager.

The post Tech Bytes: Accelerating Cloud Applications With Riverbed’s Cloud SteelHead (Sponsored) appeared first on Packet Pushers.

Cisco takes additional steps to fight counterfeit network gear

Looking to counter the growing sophistication of counterfeit networking products, Cisco recently added new layers to protect customers.“Counterfeiting hardware and software is an illegal and lucrative trade which leads to an estimated $100B loss of revenue annually across IT industries. As one of the largest and most reputable brands in the world, Cisco is often a target of counterfeiters,” said Al Palladin, legal director and  head of Global Brand Protection at Cisco.Counterfeiting presents serious risks to network quality, performance, safety, and reliability. It is dangerous because counterfeit products are not designed or built to meet the same safety standard certifications that genuine Cisco products attain, he said.To read this article in full, please click here

The Hedge Podcast #64: Brian Keys and Burnout

Burnout stalks most network engineers—and most people in the world of information technology—striking at least once in every career, it seems, and often more than once. In this episode, Brian Keys joins Eyvonne Sharp, Tom Ammon, and Russ White to discuss his personal experience with burnout. The discussion then turns to general strategies and ideas for avoiding burnout on a day-to-day basis.

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Trend data on the SolarWinds Orion compromise

Trend data on the SolarWinds Orion compromise
Trend data on the SolarWinds Orion compromise

On Sunday, December 13, FireEye released a report on a sophisticated supply chain attack leveraging SolarWinds' Orion IT monitoring software. The malware was distributed as part of regular updates to Orion and had a valid digital signature.

One of the notable features of the malware is the way it hides its network traffic using a multi-staged approach. First, the malware determines its command and control (C2) server using a domain generation algorithm (DGA) to construct and resolve a subdomain of avsvmcloud[.]com.

These algorithmically generated strings are added as a subdomain of one of the following domain names to create a new fully-qualified domain name to resolve:

.appsync-api[.]eu-west-1[.]avsvmcloud[.]com
.appsync-api[.]us-west-2[.]avsvmcloud[.]com
.appsync-api[.]us-east-1[.]avsvmcloud[.]com
.appsync-api[.]us-east-2[.]avsvmcloud[.]com

An example of such a domain name might look like: hig4gcdkgjkrt24v6isue7ax09nksd[.]appsync-api[.]eu-west-1[.]avsvmcloud[.]com

The DNS query response to a subdomain of one of the above will return a CNAME record that points to another C2 domain, which is used for data exfiltration. The following subdomains were identified as the C2 domains used for data exfiltration:

freescanonline[.]com
deftsecurity[.]com
thedoccloud[.]com
websitetheme[.]com
highdatabase[.]com
incomeupdate[.]com
databasegalore[.]com
panhardware[.]com
zupertech[.]com
virtualdataserver[.]com
Continue reading

Day Two Cloud 079: Kubernetes Is Inevitable But Not Always Necessary

There's a lot of hype and fanfare around Kubernetes, but on today's Day Two Cloud episode we'll cut through the hype with a guest who has enterprise experience with Kubernetes and containers--including the pain and problems. Those pains revolve around complexity, the ignorance of the Kubernetes platform, and the disconnect between the designers of Kubernetes and the people trying to use it now. Our guest is Eric Wright, Technology Evangelist at Turbonomic and host of the DiscoPosse podcast.