Why Do We Have Native VLANs?

Recently, my friend Andy Lapteff asked an excellent question. Why do we have native VLANs? As in, why allow untagged frames on a trunk link?

There was a time where we didn’t have VLANs. At first there was hubs, then bridges, multi-port bridges, and finally switches. Cisco was one of the first vendors to introduce VLANs, even before it became a standard, through the use of Inter Switch Links (ISL). ISL is long gone and encapsulated the entire Ethernet frame so native VLANs were not relevant there. In 1998, the 802.1Q standard was released.

In 802.1Q, 1.2 VLAN aims and benefits, the following is described:

a) VLANs are supported over all IEEE 802 LAN MAC protocols, and over shared media LANs as well as point-to-point LANs.
b) VLANs facilitate easy administration of logical groups of stations that can communicate as if they were on the same LAN. They also facilitate easier administration of moves, adds, and changes in members of these groups.
c) Traffic between VLANs is restricted. Bridges forward unicast, multicast, and broadcast traffic only
on LAN segments that serve the VLAN to which the traffic belongs.
d) As far as possible, VLANs maintain compatibility Continue reading

BGP Labs: a Year Later

Last summer, I started a long-term project to revive the BGP labs I created in the mid-1990s. I completed the original lab exercises (BGP sessions, IBGP, local preference, MED, communities) in late 2023 but then kept going. This is how far I got in a year:

• Twenty-six deploy BGP exercises, including advanced settings like AS path manipulations, MD5 passwords and BFD, and new technologies like TCP/AO and interface EBGP sessions.
• Fifteen BGP routing policies exercises, covering the basic mechanisms as well as dirty tricks like route disaggregation
• Four load balancing exercises, from EBGP ECMP to BGP Link Bandwidth and BGP Additional Paths.
• Five challenges for everyone who got bored doing the simple stuff ;)

That completes the BGP technologies I wanted to cover. I’ll keep adding the challenge labs and advanced scenarios. Here are some ideas; if you have others, please leave a comment.

blog.ipspace.net Is On Cloudflare Pages

Long story short: Years after migrating my blog to Hugo, I found the willpower to deal with the “interesting” way Cloudflare Pages deal with static HTML files, changed the Hugo URL scheme, and spent two days fixing broken links.

Apart from having the satisfaction of ticking off a long-outstanding project, the blog pages should load faster, and I won’t have to deal with GitLab hiccups anymore.

If you notice anything being broken, please let me know. Thank you!

Hedge 233: Making Heat Productive

Data centers turn large amounts of electricity into heat. Is it possible to recover even some part of this heat rather than throwing it off into the local environment? David Krebs of masterresource.org brings his vast experience with using heat from engines to bear on the problem to propose solutions.

download

Weekend Reads 070524

Anybody not involved in the telephone business will probably be surprised to find that the old TDM telephone networks are still very much alive and in place.

Intel has demonstrated an optical chiplet co-packaged with a CPU capable of supporting 4 Tbps data links to feed the increasing datacenter bandwidth requirements of AI and high performance computing (HPC) applications.

My one-liner for The AI Delusion is that the real danger today is not that computers are smarter than us but that we think computers are smarter than us and consequently trust them to make decisions they should not be trusted to make.

If the Senate passes an expansion of the Foreign Intelligence Surveillance Act, any Americanﾒs international communications could become an open book.

Anybody who builds fiber networks can describe the litany of state and local regulations involved in constructing fiber. Following are the primary kinds of such regulations ﾖ and there are others in some places.

OpenSSH maintainers have released security updates to contain a critical security flaw that could result in unauthenticated remote code execution with root privileges in glibc-based Linux systems.

This only works for so long. Software can keep getting bigger and slower only for as Continue reading

Palo Alto – Remove Unused Address Objects Using Pan-OS-PHP

If you’ve worked with Palo Alto firewalls, you might have noticed they don’t make it easy to get rid of unused address objects. It seems like such a basic feature should be included, right? While you could use Expedition for this, it requires setting up a separate server and learning a new tool, which might be more hassle than it’s worth.

I’ve talked before about using a simple Python script to clean up unused address objects (link below), but it was pretty basic and I didn't take many scenarios into account. Today, I want to show you an even easier more sophisticated way to handle this using Pan-OS-PHP. This tool is fantastic because you can use it directly from the command line. You don’t need to know any PHP to get started. Let’s look at how this can make managing your firewall a lot easier.

Palo Alto Firewall - Find and Remove Unused Address Objects

In this blog post, I’ll show you a very simple Python script to find unused address objects from the Palo Alto firewall or Panorama and remove them if needed.

PacketswitchSuresh Vina

Terraform for Network Engineers: Part Two

Before diving in, if you haven’t read the first part of this series, I highly recommend starting there. In the introductory post, we covered the basics of Terraform and explored how network engineers can leverage it.

In part two, we will:

1. Explore the provider documentation for Panorama.
2. Set up our project and create some resources and go through the Terraform workflow.
3. Review the state file.
4. Reflect on our achievements so far: Have we made our lives easier?

Provider Documentation

All Terraform providers have their documentation available on the Terraform website, following a similar structure.The Panorama provider documentation can be found here.

Here are a couple of screenshots highlighting the key sections of the Panorama provider documentation.

If you drill down into a Resource, you can find how the configuration block would look and what are the arguments you can pass to it.

Project Setup and Workflow

We'll set up all the files and folders needed to create resources on Panorama using Terraform. I prefer to keep my Terraform projects organized. Below is the structure I typically follow for my projects.

mkdir tf-neteng
cd tf-neteng
touch  Continue reading

Calico monthly roundup: June 2024

Welcome to the Calico monthly roundup: June edition! From open source news to live events, we have exciting updates to share—let’s get into it!

S&P Global 451 Market Insight: Tigera Provides Most Comprehensive CNAPP Learn how Tigera differentiates itself from competitors by focusing on runtime security, aligning with the rapidly growing market category and how it is one of the strong players in this segment. Read the blog post.

Your Guide to Observability This guide explains what observability is and shows you how to use Calico’s observability tools. With these tools, you can find and troubleshoot issues with workload communications, performance, and operations in a Kubernetes cluster.Read case study.

Customer case study: eHealth Calico helped eHealth gain visibility and implement zero-trust security controls on Amazon EKS. Read the case study to learn more. View more tradeshows.

Open source news

Kubernetes network policies: 4 pain points and how to address them – Learn about the challenges of implementing Kubernetes network policies and how to simplify their management and enhance security using Calico. Read blog post.

The power of Kubevirt and Calico – Unlock the combined power of Kubevirt and Calico for your Kubernetes environments. Learn how to streamline VM management, Continue reading

UK election day 2024: traffic trends and attacks on political parties

The 2024 UK general election, the first since Brexit officially began (January 31, 2020) and after 14 years of Conservative leadership, saw the Labour Party secure a majority. This blog post examines Internet traffic trends and cyberattack activity on election day, highlighting notable declines in traffic during the afternoon and evening as well as a DDoS attack on a political party shortly after polls closed.

For context, 2024 is considered “the year of elections,” with elections taking place in over 60 countries. We’ve covered elections in South Africa, India, Iceland, Mexico, the European Union, France, and also the 2024 US presidential debate. We also continuously update our election report on Cloudflare Radar.

The UK’s snap election on Thursday, July 4, 2024, typical of British Thursday weekday elections, contrasts with weekend elections in other countries. Polling stations were open from 07:00 to 22:00.

Generally, election days do not result in drastic changes to Internet traffic. Traffic typically dips during voting hours but not as sharply as during major events like national holidays, and rises in the evening as results are announced.

On July 4, 2024, traffic initially rose slightly from the previous week, then fell around noon Continue reading

Review: R86S (Jasper Lake – N6005)

Introduction

I am always interested in finding new hardware that is capable of running VPP. Of course, a standard issue 19” rack mountable machine like a Dell, HPE or SuperMicro machine is an obvious choice. They come with redundant power supplies, PCIe v3.0 or better expansion slots, and can boot off of mSATA or NVME, with plenty of RAM. But for some people and in some locations, the power envelope or size/cost of these 19” rack mountable machines can be prohibitive. Sometimes, just having a smaller form factor can be very useful:
Enter the GoWin R86S!

I stumbled across this lesser known build from GoWin, which is an ultra compact but modern design, featuring three 2.5GbE ethernet ports and optionally two 10GbE, or as I’ll show here, two 25GbE ports. What I really liked about the machine is that it comes with 32GB of LPDDR4 memory and can boot off of an m.2 NVME – which makes it immediately an appealing device to put in the field. I noticed that the height of the machine is just a few millimeters smaller than 1U which is 1.75” (44.5mm), which gives me the bright idea to 3D Continue reading

Cloudflare 1.1.1.1 incident on June 27, 2024

Introduction

On June 27, 2024, a small number of users globally may have noticed that 1.1.1.1 was unreachable or degraded. The root cause was a mix of BGP (Border Gateway Protocol) hijacking and a route leak.

Cloudflare was an early adopter of Resource Public Key Infrastructure (RPKI) for route origin validation (ROV). With RPKI, IP prefix owners can store and share ownership information securely, and other operators can validate BGP announcements by comparing received BGP routes with what is stored in the form of Route Origin Authorizations (ROAs). When Route Origin Validation is enforced by networks properly and prefixes are signed via ROA, the impact of a BGP hijack is greatly limited. Despite increased adoption of RPKI over the past several years and 1.1.1.0/24 being a signed resource, during the incident 1.1.1.1/32 was originated by ELETRONET S.A. (AS267613) and accepted by multiple networks, including at least one Tier 1 provider who accepted 1.1.1.1/32 as a blackhole route. This caused immediate unreachability for the DNS resolver address from over 300 networks in 70 countries was impacted, although the impact on the overall percentage of users was quite Continue reading

MUST READ: ChatGPT Is Bullshit

Bogdan Golab sent me a link to an (open access) article in Ethics and Information Technology arguing why ChatGPT is bullshit. Straight from the introduction:

Because these programs cannot themselves be concerned with truth, and because they are designed to produce text that looks truth-apt without any actual concern for truth, it seems appropriate to call their outputs bullshit.

Have fun!

D2C246: Can Service Level Objectives (SLOs) Help Keep Users Happy?

Install NordVPN on Linux for an Added Layer of Security

By default (and design), Linux is one of the most secure operating systems on the planet. That doesn’t mean, however, that you can or should assume that the out-of-the-box experience gives you all the security you need. I tend to assume this: If a computer is attached to a network, it’s vulnerable. You should always keep that in mind when considering the security of the desktop or server you are using and you should take any means possible to protect the data within and the data you transmit and receive. At this point, you’ve probably heard of virtual private networks (VPNs). They’re everywhere. Of course, the VPNs of today aren’t exactly the same as the ones we used years ago. Back in the day, when you needed to connect to your company network (to access various resources), you connected to a VPN, and your local computer was treated as if it was a part of the remote network. Although those types of VPNs are still in use across the globe, the type of VPN most people talk about today is more about privacy and security. What Modern VPNs Do Essentially, a modern VPN hides your IP address and Continue reading

First round of French election: party attacks and a modest traffic dip

This post is also available in Français.

France is currently electing a new government through early legislative elections that began on Sunday, June 30, 2024, with a second round scheduled for July 7. In this blog, we show how Cloudflare blocked DDoS attacks targeting three different French political parties.

2024 has been dubbed “the year of elections,” with elections taking place in over 60 countries, as we have mentioned before (1, 2, 3). If you regularly follow the Cloudflare blog, you’re aware that we consistently cover election-related trends, including in South Africa, India, Iceland, Mexico, the European Union and the 2024 US presidential debate. We also continuously update our election report on Cloudflare Radar.

Recently in France, as in the early stages of the war in Ukraine and during EU elections in the Netherlands, political events have precipitated cyberattacks. In France, several DDoS (Distributed Denial of Service attack) attacks targeted political parties involved in the elections over the past few days, with two parties hit just before the first round and another on election day itself.

The first political party, shown in yellow in the previous chart, experienced a DDoS attack on Continue reading

Declare your AIndependence: block AI bots, scrapers and crawlers with a single click

To help preserve a safe Internet for content creators, we’ve just launched a brand new “easy button” to block all AI bots. It’s available for all customers, including those on our free tier.

The popularity of generative AI has made the demand for content used to train models or run inference on skyrocket, and, although some AI companies clearly identify their web scraping bots, not all AI companies are being transparent. Google reportedly paid $60 million a year to license Reddit’s user generated content, Scarlett Johansson alleged OpenAI used her voice for their new personal assistant without her consent, and most recently, Perplexity has been accused of impersonating legitimate visitors in order to scrape content from websites. The value of original content in bulk has never been higher.
Last year, Cloudflare announced the ability for customers to easily block AI bots that behave well. These bots follow robots.txt, and don’t use unlicensed content to train their models or run inference for RAG applications using website data. Even though these AI bots follow the rules, Cloudflare customers overwhelmingly opt to block them.

We hear clearly that customers don’t want AI bots visiting their websites, and especially those that do Continue reading

MUST READ: ChatGPT Is Bullshit

Bogdan Golab sent me a link to an (open access) article in Ethics and Information Technology arguing why ChatGPT is bullshit. Straight from the introduction:

Because these programs cannot themselves be concerned with truth, and because they are designed to produce text that looks truth-apt without any actual concern for truth, it seems appropriate to call their outputs bullshit.

Have fun!

Master New Platforms and Technologies with netlab

One of my readers sent me this remark (probably while trying to work on the EBGP Sessions over the IPv6 LLA Interfaces lab):

I did attempt some of your labs, like IPv6 link-local-only BGP with FRR hosts, but FRR seemed not to play ball, or I was just doing it wrong.

As he was already using netlab, I could send him a cheat code:

Master New Platforms and Technologies with netlab

One of my readers sent me this remark (probably while trying to work on the EBGP Sessions over the IPv6 LLA Interfaces lab):

I did attempt some of your labs, like IPv6 link-local-only BGP with FRR hosts, but FRR seemed not to play ball, or I was just doing it wrong.

As he was already using netlab, I could send him a cheat code:

PP021: Critical Vulnerabilities, AI-Assisted Scams, Compromised VPNs, and More Security News