Enterprises are growing increasingly dependent on modern distributed applications to innovate and respond quickly to new market challenges. As applications grow in significance, the end-user experience of the application has become a key differentiator for most businesses. Understanding what kind of application performance the end-users experience, optimizing the infrastructure, and quickly identifying the source of any issues has become extremely critical.
The Modern Network framework puts the end-user experience at the forefront. It helps our customers provide the public cloud experience on-premise with an on-demand network that enforces secure connectivity and service objectives across on-premise and cloud environments. As applications become more distributed, the increased application resiliency and efficiency often comes at the cost of increased contention for shared resources. The dynamic nature of the network, device density, and the volume of data and transactions generated makes this even more challenging. Managing network complexity and simplifying network operations in such environments requires a well architected network with support for modern cloud concepts such as availability zones that provide fault tolerance. Similarly, effective network-level fault isolation requires the ability to create self-contained fault domains that facilitate network resiliency, disaster recovery and avoidance, and end-to-end root cause(s) analysis throughout the Continue reading
Achieving 100 Gbps intrusion prevention on a single server, Zhao et al., OSDI’20
Papers-we-love is hosting a mini-event this Wednesday (18th) where I’ll be leading a panel discussion including one of the authors of today’s paper choice: Justine Sherry. Please do join us if you can.
We always want more! This stems from a combination of Jevon’s paradox and the interconnectedness of systems – doing more in one area often leads to a need for more elsewhere too. At the end of the day, there are three basic ways we can increase capacity:
Options 1 and 2 are of course the ‘scale out’ options, whereas option 3 is ‘scale up’. With more nodes and more coordination comes more complexity, both in design and operation. So while scale out has seen the majority of attention in the cloud era, it’s good to remind ourselves periodically just what we really can do on a single Continue reading
Juniper’s official documentation on ZTP explains how to configure the ISC DHCP Server to automatically upgrade and configure on first boot a Juniper device. However, the proposed configuration could be a bit more elegant. This note explains how.
TL;DR
Do not redefine option 43. Instead, specify the vendor
option space to use to encode parameters with vendor-option-space.
When booting for the first time, a Juniper device requests its IP address through a DHCP discover message, then request additional parameters for autoconfiguration through a DHCP request message:
Dynamic Host Configuration Protocol (Request)
Message type: Boot Request (1)
Hardware type: Ethernet (0x01)
Hardware address length: 6
Hops: 0
Transaction ID: 0x44e3a7c9
Seconds elapsed: 0
Bootp flags: 0x8000, Broadcast flag (Broadcast)
Client IP address: 0.0.0.0
Your (client) IP address: 0.0.0.0
Next server IP address: 0.0.0.0
Relay agent IP address: 0.0.0.0
Client MAC address: 02:00:00:00:00:01 (02:00:00:00:00:01)
Client hardware address padding: 00000000000000000000
Server host name not given
Boot file name not given
Magic cookie: DHCP
Option: (54) DHCP Server Identifier (10.0.2.2)
Option: (55) Parameter Request List
Length: 14
Parameter Request List Item: (3) Router
Parameter Request List Item: (51) IP Continue readingFrom AI is wrestling with a replication crisis (HT: Drew Conry-Murray)
Last month Nature published a damning response written by 31 scientists to a study from Google Health that had appeared in the journal earlier this year. Google was describing successful trials of an AI that looked for signs of breast cancer in medical images. But according to its critics, the Google team provided so little information about its code and how it was tested that the study amounted to nothing more than a promotion of proprietary tech (emphasis mine).
No surprise there, we’ve seen it before (not to mention the “look how awesome we are, but we can’t tell you the details” Jupiter Rising article).
From AI is wrestling with a replication crisis (HT: Drew Conry-Murray)
Last month Nature published a damning response written by 31 scientists to a study from Google Health that had appeared in the journal earlier this year. Google was describing successful trials of an AI that looked for signs of breast cancer in medical images. But according to its critics, the Google team provided so little information about its code and how it was tested that the study amounted to nothing more than a promotion of proprietary tech (emphasis mine).
No surprise there, we’ve seen it before (not to mention the “look how awesome we are, but we can’t tell you the details” Jupiter Rising article).

This week, at the ACM CCS 2020 conference, researchers from UC Riverside and Tsinghua University announced a new attack against the Domain Name System (DNS) called SAD DNS (Side channel AttackeD DNS). This attack leverages recent features of the networking stack in modern operating systems (like Linux) to allow attackers to revive a classic attack category: DNS cache poisoning. As part of a coordinated disclosure effort earlier this year, the researchers contacted Cloudflare and other major DNS providers and we are happy to announce that 1.1.1.1 Public Resolver is no longer vulnerable to this attack.
In this post, we’ll explain what the vulnerability was, how it relates to previous attacks of this sort, what mitigation measures we have taken to protect our users, and future directions the industry should consider to prevent this class of attacks from being a problem in the future.
The Domain Name System (DNS) is what allows users of the Internet to get around without memorizing long sequences of numbers. What’s often called the “phonebook of the Internet” is more like a helpful system of translators that take natural language domain names (like blog.cloudflare.com or gov.uk) and Continue reading
Today's Heavy Networking podcast examines cross-domain automation. Our sponsor is Cisco and our guest is Omar Sultan, Leader, Product Management for Cisco's Network Services Orchestrator (NSO) product. While the discussion starts with NSO, the conversation also covers dealing with automation complexity, the need for tool choice, and the critical roles that organizational structure and teams play in a successful automation/orchestration effort.
The post Heavy Networking 550: Automation Readiness Isn’t About Your Routers (Sponsored) appeared first on Packet Pushers.

With the insanity of the pandemic and the knowledge drain that we’re seeing across IT in general, there’s never been a more important time than right now to help out those that are getting started on this rise. The calls for mentors across the community is heartwarming. I’ve been excited personally to see many recognizable names and faces in the Security, Networking, and Wireless communities reaching out to let people know they are available to mentor others or connect them with potential mentors. It’s a way to give back and provide servant leadership to those that need it.
If you’re someone that’s reading this blog right now and looking for a mentor you’re in luck. There are dozens of people out there that are willing to help you out. The kindness of the community is without bounds and there are those that know what it was like to wander through the wilderness for a while before getting on the right track. They are the ones that will be of the most help to you. However, before you slide into someone’s DMs looking for help, you need to keep a few things in mind.
The single Continue reading
In this podcast, we sit down with Daren Fulwell. Daren is a long-time network engineer, CCIE and CCDE, and is now a network automation evangelist. Tune in to hear about not only Daren’s journey, but a great discussion dissecting the intersection of SDN, intent-based networking, and how we need more focus on understanding operational processes and workflows to really make a dent within a network automation journey.
Reference Links:
Outro Music:
Danger Storm Kevin MacLeod (incompetech.com)
Licensed under Creative Commons: By Attribution 3.0 License
http://creativecommons.org/licenses/by/3.0/
The post NTC – A Conversation With Daren Fulwell appeared first on Network Collective.


In 2016, we launched the Cloudflare Origin CA, a certificate authority optimized for making it easy to secure the connection between Cloudflare and an origin server. Running our own CA has allowed us to support fast issuance and renewal, simple and effective revocation, and wildcard certificates for our users.
Out of the box, managing TLS certificates and keys within Kubernetes can be challenging and error prone. The secret resources have to be constructed correctly, as components expect secrets with specific fields. Some forms of domain verification require manually rotating secrets to pass. Once you're successful, don't forget to renew before the certificate expires!
cert-manager is a project to fill this operational gap, providing Kubernetes resources that manage the lifecycle of a certificate. Today we're releasing origin-ca-issuer, an extension to cert-manager integrating with Cloudflare Origin CA to easily create and renew certificates for your account's domains.
After installing cert-manager and origin-ca-issuer, you can create an OriginIssuer resource. This resource creates a binding between cert-manager and the Cloudflare API for an account. Different issuers may be connected to different Cloudflare accounts in the same Kubernetes cluster.
apiVersion: cert-manager.k8s.cloudflare.com/v1
kind: OriginIssuer
metadata:
Continue reading
After (hopefully) agreeing on what routing, bridging, and switching are, let’s focus on the first important topic in this area: how do we get a packet across the network? Yet again, there are three fundamentally different technologies:
More details in the Getting Packets Across the Network video.
After (hopefully) agreeing on what routing, bridging, and switching are, let’s focus on the first important topic in this area: how do we get a packet across the network? Yet again, there are three fundamentally different technologies:
More details in the Getting Packets Across the Network video.