How BGP Really Converges

This lesson in Russ White’s BGP course gets into withdrawing a route, MRAI time, implicit withdraws, BGP Hunt, graceful restart, and other topics.

Original link at Packet Pushers here

Weekend Reads 052722

networks and policy

Leading off this weekend, an article by Simon Sharwood on the impact of the centralization of the Internet. I wrote a somewhat longer article on the Public Discourse a while back on the same topic.

The internet has become smaller, the result of a rethinking of when and where to use the ‘net’s intended architecture. In the process it may also have further concentrated power in the hands of giant technology companies.

Is softwarization really going to change the way we build networks from the ground up? I suspect things will change, but they’ve always changed. I also suspect we’ll be hearing about how software is going to eat the world ten years from now, and IPv6 still won’t be fully deployed.

DOCSIS 4.0 is set to deliver faster speeds for cable network operators, but the next generation technology will also spur an operational sea change, telecom consultant Sean McDevitt told Fierce.

By default, the Docker server configures container networks for IPv4-only, so I had a hard time running it in this environment.

security and other technologies

This one on Costa Rica is a serious warning—

A ransomware gang that infiltrated some Costa Rican government computer Continue reading

Hedge 131: Easier for the Computer or the Person?

One of the mainstays of scripting—and now network management—are increasingly focused on making things “easier” for the human operator. Does this focus on making things “easier” for the operator produce a better experience, though? Or does it create frustration as humans try to “outguess” the computer’s programming and process? Join Tom Ammon and Russ White as they discuss the problems with scripting, automation, and ease-of-use.

download

Learning BGP Module 2 Lesson 4: Best Path – Video

This installment of Russ White’s BGP course discusses how the BGP protocol calculates the best path for a route. Topics include: -Routes to discard -Weighting -Shortest AS path -Origin type -Multi-Exit Discriminator (MED) -Oldest eBGP Path -Tiebreakers You can subscribe to the Packet Pushers’ YouTube channel for more videos as they are published. It’s a […]

The post Learning BGP Module 2 Lesson 4: Best Path – Video appeared first on Packet Pushers.

Learning BGP Module 2 Lesson 3: Messages And Updates – Video

Russ White’s BGP course continues with a lesson on messages and updates. Topics include: -BGP Open -BGP Reach -BGP MP-Reach -Address families -BGP Update -Update processing -TCP interaction You can subscribe to the Packet Pushers’ YouTube channel for more videos as they are published. It’s a diverse a mix of content from Ethan and Greg, […]

The post Learning BGP Module 2 Lesson 3: Messages And Updates – Video appeared first on Packet Pushers.

Weekend Reads 052022

The steepening trajectory towards event-driven and real-time API architecture is imminent.

The idea of this declaration has a lot to do with the “Past of the Internet.” When the Internet was developing in the 1980s and 1990s, it was seen primarily as a tool that would expand individual freedoms worldwide, strengthen democracy, and create prosperity through innovation and economic progress.

I’m not sure that most people understand the extent to which our online experience has moved to the cloud – and this movement to the cloud means we’re using a lot more bandwidth than in the recent past.

Among the many disruptions facing modern communication service providers (CSPs), one of the biggest is the growing role of data centers (DCs) in their business.

A bargain-basement, $5 price tag on a 3-year-old remote access Trojan (RAT) has concerned some security researchers, who see the move as signs of a possible race to the bottom in terms of pricing — or that new, disrupting developers are entering the cybercriminal market.

Researchers are marveling at the scope and magnitude of a vulnerability that hackers are actively exploiting to take full control of network devices that run on some of the world’s biggest Continue reading

Hedge 130: The Importance of Network Inventories

Inventories are generally hard, and hence don’t tend to be where you’d like to spend your time. The importance of having a good inventory, however, can hardly be overstated. Malcom Booden joins Tom Ammon and Russ White to talk about the importance of inventories and inventory ideas.

download

OT’N: BGP Loop Free Paths

Over at Packet Pushers—

Russ White’s BGP series continues with a discussion of building loop-free paths with the Border Gateway Protocol (BGP). Topics include AS (Autonomous System) paths, loop prevention, why loop checks are inbound, and more on IBGP and EBGP.

Learning BGP Module 2 Lesson 2: Peering, Part 2 – Video

Russ White continues the discussion about BGP peering in part two of this lesson. Topics covered include: -Challenges with link-local next hop with IPv6 -How different BGP implementations handle these challenges -Promiscuous peering -Mitigating the attack surface of promiscuous peers -BGP Capabilities -Filtering before advertising/RFC 8212 You can subscribe to the Packet Pushers’ YouTube channel […]

The post Learning BGP Module 2 Lesson 2: Peering, Part 2 – Video appeared first on Packet Pushers.

Learning BGP Module 2 Lesson 1: Peering Part 1 – Video

The first video in this second module of Russ White’s BGP course covers peering, including why BGP uses TCP for transport, passive and active peer, multi-hop peering, collisions, and more. Russ White is a network architect, author, and instructor. You can subscribe to the Packet Pushers’ YouTube channel for more videos as they are published. […]

The post Learning BGP Module 2 Lesson 1: Peering Part 1 – Video appeared first on Packet Pushers.

Weekend Reads 051322

Cloudflare, a company that specializes in web security and distributed denial of service (DDoS) attack mitigation, just reported that it managed to stop an attack of an unprecedented scale.

Cloud operators provide price incentives so that users gravitate towards newer generations (and between server architectures). Figure 1 shows lines of best fit for the average cost per virtual central processing unit (vCPU, essentially a physical processor thread as most processor cores run two threads simultaneously) of a range of AWS virtual instances over time.

Passwordless sign-ins are already a practical reality, but they’re sometimes clunky — and three of the biggest tech companies believe they can reduce the friction.

Within a decade, the growth of powerful quantum computers will lead to a new era in security, in which once-impenetrable public-key techniques like RSA and ECC will fall to higher levels of brute force.

Cisco Systems on Wednesday shipped security patches to contain three flaws impacting its Enterprise NFV Infrastructure Software (NFVIS) that could permit an attacker to fully compromise and take control over the hosts.

Developers understand the importance of security, and overwhelmingly want to deploy secure and quality code, but software vulnerabilities continue to be exploited.

The National Institute Continue reading

Learning BGP Module 1 Lesson 4: Intra-AS Models And Route Reflectors – Video

This lesson in Russ White’s BGP course delves into synchronization within an Autonomous System (AS) and confederation within an AS. It also discusses route reflectors, including how they prevent loops, route reflector clients, route reflector multi-path, and multi-path pros and cons. Russ White is a network architect, author, and instructor. You can subscribe to the […]

The post Learning BGP Module 1 Lesson 4: Intra-AS Models And Route Reflectors – Video appeared first on Packet Pushers.

Learning BGP Module 1 Lesson 3: How BGP Really Converges – Video

This lesson in Russ White’s BGP course gets into withdrawing a route, MRAI time, implicit withdraws, BGP Hunt, graceful restart, and other topics. Russ White is a network architect, author, and instructor. You can subscribe to the Packet Pushers’ YouTube channel for more videos as they are published. It’s a diverse a mix of content […]

The post Learning BGP Module 1 Lesson 3: How BGP Really Converges – Video appeared first on Packet Pushers.

Hedge 129: Open Source Mentoring

Mentoring is a topic we return to time and again—because it’s one of the most important things we can talk about in terms of building your people skills, your knowledge, and your career. On this episode of the Hedge, Guedis Cardenas joins Tom Ammon and Russ White to talk about open source mentoring. We discuss how this is different than “regular” mentoring, and how it’s the same. Join us as we talk about one of the most important career and personal growth things you can do.

download

BGP Policy (Part 7)

At the most basic level, there are only three BGP policies: pushing traffic through a specific exit point; pulling traffic through a specific entry point; preventing a remote AS (more than one AS hop away) from transiting your AS to reach a specific destination. In this series I’m going to discuss different reasons for these kinds of policies, and different ways to implement them in interdomain BGP.

In this post—the last post in this series—I’m going to cover do not transit options from the perspective of AS65001 in the following network—

There are cases where an operator does not traffic to be forwarded to them through some specific AS, whether directly connected or multiple hops away. For instance, AS65001 and AS65005 might be operated by companies in politically unfriendly nations. In this case, AS65001 may be legally required to reject traffic that has passed through the nation in which AS65005 is located. There are at least three mechanisms in BGP that are used, in different situations, to enforce this kind of policy.

Do Not Advertise Communities (Provider Specific)

Many providers supply communities a customer can use to block the advertisement of their routes to a particular AS. For instance, if Continue reading

Controversial Reads 050722

In January a federal judge denied Facebook’s motion to dismiss the Federal Trade Commission’s amended complaint seeking to force the company to sell off Instagram and WhatsApp.

Tech companies earn staggering profits by targeting ads to us based on our online behavior. This incentivizes all online actors to collect as much of our behavioral information as possible, and then sell it to ad tech companies and the data brokers that service them.

And often, when doing business in these countries, company’s interests in revenue and profits conflict with America’s national security interests, a conflict that profit always seems to win.

European Union lawmakers voted today in favor of controversial measures to outlaw anonymous crypto transactions, a move the industry said would stifle innovation and invade privacy.

His story is sobering: “The pressure comes from both above and below. You’ve got the United States Senate basically saying: ‘Nice little social network you got there. Real shame for anything to happen to it.’… From below, you’ve got the employees and the tweet mobs and basically forming these boycotts and subjecting the management of the company to pressure.

Twitter founder Jack Dorsey would like you to know he too misses the early Continue reading

Weekend Reads 050622

Video meetings dampen brainstorming because we are so hyper-focused on the face in that box that we don’t let our eyes and minds wander as much, a new study found.

Have you recently been on a video confefence call, hit the “mute” button and then offered up some nasty comments about a client or a colleague — or even the boss?

Comcast and other broadband providers are utilizing 10G technology in their quest to deliver “multigigabit symmetrical speeds” to the consumer market.

Yet, simultaneously, AI has been touted as both a panacea to virtually any problem in any field, as well as the source of humankind’s demise. “AI will push us to boundless innovation,” “AI will go rogue,” – across the industry, there remains a mix of skepticism and fear on how AI will specifically impact us as individuals.

It’s not often we can say this, but 2022 is shaping up to be an exciting time in information governance, especially for those interested in compliance and compliance frameworks.

Janczewski thought again of the investigative method that had brought them there like a digital divining rod, revealing a hidden layer of illicit connections underlying the visible world. He hoped, not for Continue reading

Hedge May Update

A short update on upcoming classes and episodes of the Hedge for May, as well an update on what I’m working on and other places where I’m publishing material.

Live Training: How Routers Really Work

On the 27th of May, I’ll be teaching a three-hour course called How Routers Really Work? From the course description:

This training will peer into the internal components of a router, starting with an explanation of how a router switches packets. This walk through of a switching path, in turn, will be used as a foundation for explaining the components of a router, including the various tables used to build forwarding tables and the software components used to build these tables.

Sign up here.

Hedge 128: Network Engineering at College

Have you ever thought about getting a college degree in computer networking? What are the tradeoffs between this and getting a certification? What is the state of network engineering at colleges—what do current students in network engineering programs think about their programs, and what they wish was there that isn’t? Rick Graziani joins Tom Ammon and Russ White in a broad ranging discussion on network engineering and college. Rick teaches network engineering full time in the Valley.

download