
Author Archives: Russ
Author Archives: Russ
In most areas of life, where the are standards, there is some kind of enforcing agency. For instance, there are water standards, and there is a water department that enforces these standards. There are electrical standards, and there is an entire infrastructure of organizations that make certain the fewest number of people are electrocuted as possible each year. What about Internet standards? Most people are surprised when they realize there is no such thing as a “standards police” in the Internet.
Listen in as George Michaelson, Evyonne Sharp, Tom Ammon, and Russ White discuss the reality of standards enforcement in the Internet ecosystem.
There is never enough. Whatever you name in the world of networking, there is simply not enough. There are not enough ports. There is not enough speed. There is not enough bandwidth. Many times, the problem of “not enough” manifests itself as “too much”—there is too much buffering and there are too many packets being dropped. Not so long ago, the Internet community decided there were not enough IP addresses and decided to expand the address space from 32 bits in IPv4 to 128 bits in IPv6. The IPv6 address space is almost unimaginably huge—2 to the 128th power is about 340 trillion, trillion, trillion addresses. That is enough to provide addresses to stacks of 10 billion computers blanketing the entire Earth. Even a single subnet of this space is enough to provide addresses for a full data center where hundreds of virtual machines are being created every minute; each /64 (the default allocation size for an IPv6 address) contains 4 billion IPv4 address spaces.
But… what if the current IPv6 address space simply is not enough? Engineers working in the IETF have created two different solutions over the years for just this eventuality. In 1994 RFC1606 provided a Continue reading
What if you could connect a lot of devices to the Internet—without any kind of firewall or other protection—and observe attackers trying to find their way “in?” What might you learn from such an exercise? One thing you might learn is a lot of attacks seem to originate from within a relatively small group of IP addresses—IP addresses acing badly. Listen in as Leslie Daigle of Thinking Cat and the Techsequences podcast, Tom Ammon, and Russ White discuss just such an experiment and its results.
A couple of weeks ago, I joined Leslie Daigle and Alexa Reid on Techsequences to talk about free speech and the physical platform—does the right to free speech include the right to build and operate physical facilities like printing presses and web hosting? I argue it does. Listen in if you want to hear my argument, and how this relates to situations such as the “takedown” of Parler.
While reading a research paper on address spoofing from 2019, I ran into this on NAT (really PAT) failures—
The authors state 49% of the NATs they discovered in their investigation of spoofed addresses fail in one of these two ways. From what I remember way back when the first NAT/PAT device (the PIX) was deployed in the real world (I worked in TAC at the time), there was a lot of discussion about what a firewall should do with packets sourced from addresses not indicated anywhere.
If I have an access list including 192.168.1.0/24, and I get a packet sourced from 192.168.2.24, Continue reading
Automation is surely one of the best things to come to the networking world—the ability to consistently apply a set of changes across a wide array of network devices has speed at which network engineers can respond to customer requests, increased the security of the network, and reduced the number of hours required to build and maintain large-scale systems. There are downsides to automation, as well—particularly when operators begin to rely on automation to solve problems that really should be solved someplace else.
In this episode of the Hedge, Andrew Wertkin from Bluecat Networks joins Tom Ammon and Russ White to discuss the naïve reliance on automation.
I’m teaching a webinar on router internals through Pearson (Safari Books Online) on the 23rd of July. From the abstract—
A network device—such as a router, switch, or firewall—is often seen as a single “thing,” an abstract appliance that is purchased, deployed, managed, and removed from service as a single unit. While network devices do connect to other devices, receiving and forwarding packets and participating in a unified control plane, they are not seen as a “system” in themselves.
What is the first thing almost every training course in routing protocols begin with? Building adjacencies. What is considered the “deep stuff” in routing protocols? Knowing packet formats and processes down to the bit level. What is considered the place where the rubber meets the road? How to configure the protocol.
I’m not trying to cast aspersions at widely available training, but I sense we have this all wrong—and this is a sense I’ve had ever since my first book was released in 1999. It’s always hard for me to put my finger on why I consider this way of thinking about network engineering less-than-optimal, or why we approach training this way.
This, however, is one thing I think is going on here—
We believe that by knowing ever-deeper reaches of detail about a protocol, we are not only more educated engineers, but we will be able to make better decisions in the design and troubleshooting spaces.
To some degree, we think we are managing the Continue reading
Bluecat, in cooperation with an outside research consultant, jut finished a survey and study on the lack of communication and divisions between the cloud and networking teams in deployments to support business operations. Dana Iskoldski joins Tom Ammon and Russ White to discuss the findings of their study, and make some suggestions about how we can improve communication between the two teams.
Please find a copy of the study at http://bluecatnetworks.com/hedge.
I often feel like I’m “behind” on what I need to get done. Being a bit metacognitive, however, I often find this feeling is more related to not organizing things well, which means I often feel like I have so much to do “right now” that I just don’t know what to do next—hence “processor thrashing on process scheduler.” Todd Palino joins this episode of the Hedge to talk about the “Getting Things Done” technique (or system) of, well … getting things done.
It’s not unusual in the life of a network engineer to go entire weeks, perhaps even months, without “getting anything done.” This might seem odd for those who do not work in and around the odd combination of layer 1, layer 3, layer 7, and layer 9 problems network engineers must span and understand, but it’s normal for those in the field. For instance, a simple request to support a new application might require the implementation of some feature, which in turn requires upgrading several thousand devices, leading to the discovery that some number of these devices simply do not support the new software version, requiring a purchase order and change management plan to be put in place to replace those devices, which results in … The chain of dominoes, once it begins, never seems to end.
Or, as those who have dealt with these problems many times might say, it is more complicated than you think. This is such a useful phrase, in fact, it has been codified as a standard rule of networking in RFC1925 (rule 8, to be precise).
Take, for instance, the problem of sending documents through electronic mail—in the real world, there are various Continue reading