LISP vs EVPN: Mobility in Campus Networks
I decided not to get involved in the EVPN-versus-LISP debates anymore; I’d written everything I had to say about LISP. However, I still get annoyed when experienced networking engineers fall for marketing gimmicks disguised as technical arguments. Here’s a recent one:
Narrowboat: Lessons learnt
At this stage of the build internally there is only really the bedroom, snags and trims (windows, ceiling edges and doors) left to do. I am currently in Australia having a bit of RnR so this is a reflective post to show the build at its present state and go through the things I have learnt along the way. I could plan all I like but as I haven’t lived on a boat before there was always going to be a few wrong design decisions.
D2C239: “(Almost) Every Infrastructure Decision I Endorse or Regret”
You can’t just drop a knife on fish and expect there to be sushi. Jack Lindamood joins us today to share his metaphors and thoughts on picking the right IT tools and processes as outlined in his popular article, “(Almost) Every Infrastructure Decision I Endorse or Regret after 4 Years Running Infrastructure at a Startup.”... Read more »Modernizing IT Networks for Higher Education
In today’s data-driven world, higher educational institution networks and their management must be modernized to address the needs of everyone across campus. Enterprises face similar challenges and also need to modernize their networks.Stateful Firewall Cluster High Availability Theater
Dmitry Perets wrote an excellent description of how typical firewall cluster solutions implement control-plane high availability, in particular, the routing protocol Graceful Restart feature (slightly edited):
Most of the HA clustering solutions for stateful firewalls that I know implement a single-brain model, where the entire cluster is seen by the outside network as a single node. The node that is currently primary runs the control plane (hence, I call it single-brain). Sessions and the forwarding plane are synchronized between the nodes.
Stateful Firewall Cluster High Availability Theater
Dmitry Perets wrote an excellent description of how typical firewall cluster solutions implement control-plane high availability, in particular, the routing protocol Graceful Restart feature (slightly edited):
Most of the HA clustering solutions for stateful firewalls that I know implement a single-brain model, where the entire cluster is seen by the outside network as a single node. The node that is currently primary runs the control plane (hence, I call it single-brain). Sessions and the forwarding plane are synchronized between the nodes.
1000BASE-T Part 4 – Link Down Detection
In the previous three parts, we learned about all the interesting things that go on in the PHY with scrambling, descrambling, synchronization, auto negotiation, FEC encoding, and so on. This is all essential knowledge that we need to have to understand how the PHY can detect that a link has gone down, or is performing so badly that it doesn’t make sense to keep the link up.
What Does IEEE 802.3 1000BASE-T Say?
The function in 1000BASE-T that is responsible for monitoring the status of the link is called link monitor and is defined in 40.4.2.5. The standard does not define much on what goes on in link monitor, though. Below is an excerpt from the standard:
Link Monitor determines the status of the underlying receive channel and communicates it via the variable
link_status. Failure of the underlying receive channel typically causes the PMA’s clients to suspend normal
operation.
The Link Monitor function shall comply with the state diagram of Figure 40–17.
The state diagram (redrawn by me) is shown below:
While 1000BASE-T leaves what the PHY monitors in link monitor to the implementer, there are still some interesting variables and timers that you should be Continue reading
HS069: Regulating AI
In today’s episode Greg and Johna spar over how, when, and why to regulate AI. Does early regulation lead to bad regulation? Does late regulation lead to a situation beyond democratic control? Comparing nascent regulation efforts in the EU, UK, and US, they analyze socio-legal principles like privacy and distributed liability. Most importantly, Johna drives... Read more »
PP009: Don’t Forget the Firmware
If your approach to firmware is that you don’t bother it as long as it doesn’t bother you, you might want to listen to this episode. Concerns about supply chain vulnerabilities are on the rise and for good reason: Attackers are targeting firmware because compromising this software can allow attackers to persist on systems after... Read more »Prevent Data Exfiltration in Kubernetes: The Critical Role of Egress Access Controls
Data exfiltration and ransomware attacks in cloud-native applications are evolving cyber threats that pose significant risks to organizations, leading to substantial financial losses, reputational damage, and operational disruptions. As Kubernetes adoption grows for running containerized applications, it becomes imperative to address the unique security challenges it presents. This article explores the economic impact of data exfiltration and ransomware attacks, their modus operandi in Kubernetes environments, and effective strategies to secure egress traffic. We will delve into the implementation of DNS policies and networksets, their role in simplifying egress control enforcement, and the importance of monitoring and alerting for suspicious egress activity. By adopting these measures, organizations can strengthen their containerized application’s security posture running in Kubernetes and mitigate the risks associated with these prevalent cyber threats.
Economic impact of data exfiltration and ransomware attacks
Data exfiltration and ransomware attacks have emerged as formidable threats to organizations worldwide, causing substantial financial losses and service outage. According to IBM’s 2023 Cost of a Data Breach report, data exfiltration attacks alone cost businesses an average of $3.86 million per incident, a staggering figure that underscores the severity of this issue. Ransomware attacks, on the other hand, can inflict even more damage, with Continue reading
Cisco-led Big Tech Consortium Addresses the AI Skills Gap
By combining resources and expertise, the AI-Enabled ICT Workforce Consortium will offer a blueprint for how industries can adapt to an AI-dominated future.SR/MPLS Security Framework
A long-time friend sent me this question:
I would like your advice or a reference to a security framework I must consider when building a green field backbone in SR/MPLS.
Before going into the details, keep in mind that the core SR/MPLS functionality is not much different than the traditional MPLS:
SR/MPLS Security Framework
A long-time friend sent me this question:
I would like your advice or a reference to a security framework I must consider when building a green field backbone in SR/MPLS.
Before going into the details, keep in mind that the core SR/MPLS functionality is not much different than the traditional MPLS:
Total eclipse of the Internet: traffic impacts in Mexico, the US, and Canada
There are events that unite people, like a total solar eclipse, reminding us, humans living on planet Earth, of our shared dependence on the sun. Excitement was obvious in Mexico, several US states, and Canada during the total solar eclipse that occurred on April 8, 2024. Dubbed the Great North American Eclipse, millions gathered outdoors to witness the Moon pass between Earth and the Sun, casting darkness over fortunate states. Amidst the typical gesture of putting the eclipse glasses on and taking them off, depending on if people were looking at the sky during the total eclipse, or before or after, what happened to Internet traffic?
Cloudflare’s data shows a clear impact on Internet traffic from Mexico to Canada, following the path of totality. The eclipse occurred between 15:42 UTC and 20:52 UTC, moving from south to north, as seen in this NASA image of the path and percentage of darkness of the eclipse.
Looking at the United States in aggregate terms, bytes delivered traffic dropped by 8%, and request traffic by 12% as compared to the previous week at 19:00 UTC Continue reading
Mixed Results For The Datacenter Thundering Thirteen In Q4
We have been tracking the financial results for the big players in the datacenter that are public companies for three and a half decades, but starting last year we started dicing and slicing the numbers for the largest IT suppliers for stuff that goes into datacenters so we can give you a better sense what is and what is not happening out there. …
Mixed Results For The Datacenter Thundering Thirteen In Q4 was written by Timothy Prickett Morgan at The Next Platform.