Introducing Ephemeral IDs: a new tool for fraud detection
In the early days of the Internet, a single IP address was a reliable indicator of a single user. However, today’s Internet is more complex. Shared IP addresses are now common, with users connecting via mobile IP address pools, VPNs, or behind CGNAT (Carrier Grade Network Address Translation). This makes relying on IP addresses alone a weak method to combat modern threats like automated attacks and fraudulent activity. Additionally, many Internet users have no option but to use an IP address which they don’t have sole control over, and as such, should not be penalized for that.
At Cloudflare, we are solving this complexity with Turnstile, our CAPTCHA alternative. And now, we’re taking the next step in advancing security with Ephemeral IDs, a new feature that generates a unique short-lived ID, without relying on any network-level information.
When a website visitor interacts with Turnstile, we now calculate an Ephemeral ID that can link behavior to a specific client instead of an IP address. This means that even when attackers rotate through large pools of IP addresses, we can still identify and block malicious actions. For example, in attacks like credential stuffing or account signups, where fraudsters attempt to disguise Continue reading
Start auditing and controlling the AI models accessing your content
Site owners have lacked the ability to determine how AI services use their content for training or other purposes. Today, Cloudflare is releasing a set of tools to make it easy for site owners, creators, and publishers to take back control over how their content is made available to AI-related bots and crawlers. All Cloudflare customers can now audit and control how AI models access the content on their site.
This launch starts with a detailed analytics view of the AI services that crawl your site and the specific content they access. Customers can review activity by AI provider, by type of bot, and which sections of their site are most popular. This data is available to every site on Cloudflare and does not require any configuration.
We expect that this new level of visibility will prompt teams to make a decision about their exposure to AI crawlers. To help give them time to make that decision, Cloudflare now provides a one-click option in our dashboard to immediately block any AI crawlers from accessing any site. Teams can then use this “pause” to decide if they want to allow specific AI providers or types of bots to proceed. Once that Continue reading
Egress Peer Engineering: basics
Egress Peer Engineering extends regular BGP policies to provide more flexibility.
Why use Egress Peer Engineering
When a network operator has multiple external connections, such as IP transit, private peerings or Internet Exchange (IXP), there is often a need to …
NAT Overload Towards Specific Host
This is a quick post on how to perform NAT overload (PAT) towards a specific host only. I have an inside network of 10.10.1.0/24. I need a host in this network to reach the host 192.168.0.1. They don’t have direct connectivity so I need to PAT it behind the router which has an IP of 192.168.128.103. I don’t want to PAT all the traffic from 10.10.1.0/24, though, only towards this specific host. There are hosts in 192.168.128.0/24 that the VM should access using its original source. The network is shown in the diagram below:
First, I’ll define my inside and outside interface:
RT01(config)#int gi0/0 RT01(config-if)#ip nat inside RT01(config-if)#int gi0/1 RT01(config-if)#ip nat outside
Then I’m going to create the ACL that matches on traffic from the 10.10.1.0/24 network to the host 192.168.0.1:
RT01(config)#ip access-list extended NAT-SRC-10.10.2.0/24 RT01(config-ext-nacl)#permit ip 10.10.2.0 0.0.255.255 host 192.168.0.1
Then, I’ll configure the NAT statement to match on the ACL and do an overload to interface Gi0/1:
RT01(config)#ip nat inside source list NAT-SRC-10.10.2. Continue reading
IBGP Load Balancing with BGP Link Bandwidth
In the previous BGP load balancing lab exercise, I described the BGP Link Bandwidth attribute and how you can use it on EBGP sessions. This lab moves the unequal-cost load balancing into your network; we’ll use the BGP Link Bandwidth attribute on IBGP sessions.
Cloudflare’s 2024 Annual Founders’ Letter
This week Cloudflare will celebrate the fourteenth anniversary of our launch. We think of it as our birthday. As is our tradition ever since our first anniversary, we use our Birthday Week each year to launch new products that we think of as gifts back to the Internet. For the last five years, we also take this time to write our annual Founders’ Letter reflecting on our business and the state of the Internet. This year is no different.
That said, one thing that is different is you may have noticed we've actually had fewer public innovation weeks over the last year than usual. That's been because a couple of incidents nearly a year ago caused us to focus on improving our internal systems over releasing new features. We're incredibly proud of our team's focus to make security, resilience, and reliability the top priorities for the last year. Today, Cloudflare's underlying platform, and the products that run on top of it, are significantly more robust than ever before.
With that work largely complete, and our platform in its strongest shape ever, we plan to pick back up the usual cadence of new product launches that we're known for. This Continue reading
Logging in Python
How many times have you found yourself staring at your screen, surrounded by a sea of hastily added print statements, thinking "There's got to be a better way"? If you're like me, the answer is probably "more times than I'd care to admit."
Sick of finding myself in this situation more often than I'd like, I decided to take action. Python's default logging module is powerful, but it just didn't cut it for my needs. I was looking for something more.
Why Logging Matters
Before we dive in, let's look at why logging is crucial:
- Debugging: Logs provide a trail of breadcrumbs to track down issues.
- Monitoring: They help you understand your application's behavior.
- Auditing: Logs can serve as a record of important events or actions.
- Performance Tracking: You can use logs to identify bottlenecks and optimize your code.
Introducing PyLogger
With these benefits in mind, I set out to build a custom logging class that would meet all my requirements. The result is PyLogger, a Python logging class that aims to make logging both powerful and user-friendly.
Key Features
Below are some of the key features that make pylogger appealing:
- Flexible Continue reading
IPv6: Instructions for Use
Retirement obviously does not sit well with my friend Tiziano Tofoni; the English version of his IPv6 book just came out.
It is a bit sad, though, that we still need “how to use IPv6” books when the protocol is old enough to enjoy a nice glass of whiskey (in the US) trying to drown its sorrow at its slow adoption.
HN750: Under the Hood Of Palo Alto Networks Prisma Access Browser (Sponsored)
On today’s Heavy Networking, we discuss enterprise browsers with sponsor Palo Alto Networks. Most end users do the majority of their work in the browser these days. At the same time, more threats are coming in via the Web and Web-based apps. Palo Alto Networks recently launched its Prisma Access browser, a Chromium-based browser designed... Read more »Creating a Simple GUI Application with Python Tkinter
A few years ago, I used a simple application called 'TypeItIn'. It kept a small GUI window open with some buttons and labels. You could configure each label with your own text. If you wanted to type one of these texts into a window, all you needed to do was click on the label, and it would start typing the text into whatever window you opened. It was such a time-saver, especially if you had multiple texts that you often used.
Fast forward a few years, I really needed such a tool and then realized I knew a bit of Python, so I should be able to create the same functionality using Python. So, in this blog post, let's go through how you can create a simple GUI application with just a few lines of code.
What Is Tkinter?
Tkinter is the standard GUI toolkit for Python, providing a fast and easy way to create simple GUI applications. It is built into Python, so there’s no need to install anything separately if you already have Python.
Tkinter is widely used due to its simplicity and the vast availability of widgets like buttons, menus, and text fields, which help Continue reading
TNO003: DevOps, NetOps, and Batman – Part 1
Do you know what DevOps is? Really? And how well does it fit traditional NetOps? Host Scott Robohn and guest Tom McGonagle explore ways to apply DevOps to Network Engineering and Operations. They review the seven DevOps practices and Tom’s proposed adaptations of DevOps under the banner of GitNops. This is the first part of... Read more »Hedge 244: Networks for AI
What are the requirements for running AI workloads over a data center fabric? Why is InfiniBand so popular for building AI networks? What about Ethernet for AI? Jeff Tantsura joins Tom Ammon and Russ White to discuss networks for AI workloads.
Removing uncertainty through “what-if” capacity planning
Infrastructure planning for a network serving more than 81 million requests at peak and which is globally distributed across more than 330 cities in 120+ countries is complex. The capacity planning team at Cloudflare ensures there is enough capacity in place all over the world so that our customers have one less thing to worry about - our infrastructure, which should just work. Through our processes, the team puts careful consideration into “what-ifs”. What if something unexpected happens and one of our data centers fails? What if one of our largest customers triples, or quadruples their request count? Across a gamut of scenarios like these, the team works to understand where traffic will be served from and how the Cloudflare customer experience may change.
This blog post gives a look behind the curtain of how these scenarios are modeled at Cloudflare, and why it's so critical for our customers.
Scenario planning and our customers
Cloudflare customers rely on the data centers that Cloudflare has deployed all over the world, placing us within 50 ms of approximately 95% of the Internet-connected population globally. But round-trip time to our end users means little if those data centers don’t have the capacity Continue reading
Cloudflare incident on September 17, 2024
On September 17, 2024, during routine maintenance, Cloudflare inadvertently stopped announcing fifteen IPv4 prefixes, affecting some Business plan websites for approximately one hour. During this time, IPv4 traffic for these customers would not have reached Cloudflare, and users attempting to connect to websites assigned addresses within those prefixes would have received errors.
We’re very sorry for this outage.
This outage was the result of an internal software error and not the result of an attack. In this blog post, we’re going to talk about what the failure was, why it occurred, and what we’re doing to make sure this doesn’t happen again.
Background
Cloudflare assembled a dedicated Addressing team in 2019 to simplify the ways that IP addresses are used across Cloudflare products and services. The team builds and maintains systems that help Cloudflare conserve and manage its own network resources. The Addressing team also manages periodic changes to the assignment of IP addresses across infrastructure and services at Cloudflare. In this case, our goal was to reduce the number of IPv4 addresses used for customer websites, allowing us to free up addresses for other purposes, like deploying infrastructure in new locations. Since IPv4 addresses are a finite Continue reading
Repost: Building Layer-3-Only EVPN Lab
In early August, I published step-by-step instructions for a lab you can use to explore how to implement pure L3VPN with an EVPN control plane.
How Cloudflare is helping domain owners with the upcoming Entrust CA distrust by Chrome and Mozilla
Chrome and Mozilla announced that they will stop trusting Entrust’s public TLS certificates issued after November 12, 2024 and December 1, 2024, respectively. This decision stems from concerns related to Entrust’s ability to meet the CA/Browser Forum’s requirements for a publicly trusted certificate authority (CA). To prevent Entrust customers from being impacted by this change, Entrust has announced that they are partnering with SSL.com, a publicly trusted CA, and will be issuing certs from SSL.com’s roots to ensure that they can continue to provide their customers with certificates that are trusted by Chrome and Mozilla.
We’re excited to announce that we’re going to be adding SSL.com as a certificate authority that Cloudflare customers can use. This means that Cloudflare customers that are currently relying on Entrust as a CA and uploading their certificate manually to Cloudflare will now be able to rely on Cloudflare’s certificate management pipeline for automatic issuance and renewal of SSL.com certificates.
CA distrust: responsibilities, repercussions, and responses
With great power comes great responsibility Every publicly trusted certificate authority (CA) is responsible for maintaining a high standard of security and compliance to ensure that the certificates they issue are trustworthy. Continue reading
IPB160: The Making of RFC 9637 – IPv6 Documentation Prefix
IPv6 Buzz welcomes back Nick Buraglio, a frequent guest, to discuss RFC 9637. We get into the details of RFC 9637, which describes the new documentation prefix space for IPv6. We also explore the process of how RFCs go from idea to standard in the IETF. (Cue the “I’m Just a Bill” song from Schoolhouse... Read more »Custom netlab Reports
A previous blog post described how you can use the netlab report functionality to generate addressing, wiring, BGP, and OSPF reports from a running lab. But what could you do if you need a report that doesn’t exist yet? It’s straightforward to define one (what else did you expect?).
Let’s create the report I used in the EVPN Hub-and-Spoke Layer-3 VPN blog post to create the VRF table.