How The Gambia lost access to the Internet for more than 8 hours

How The Gambia lost access to the Internet for more than 8 hours
How The Gambia lost access to the Internet for more than 8 hours

Internet outages are more common than most people think, and may be caused by misconfigurations, power outages, extreme weather, or infrastructure damage. Note that such outages are distinct from state-imposed shutdowns that also happen all too frequently, generally used to deal with situations of unrest, elections or even exams.

On the morning of January 4, 2022, citizens of The Gambia woke up to a country-wide Internet outage. Gamtel (the main state-owned telecommunications company of the West Africa country), announced that it happened due to "technical issues on the backup links" — we elaborate more on this below.

Cloudflare Radar shows that the outage had a significant impact on Internet traffic in the country and started after 01:00 UTC (which is the same local time), lasting until ~09:45 — a disruption of over 8 hours.

How The Gambia lost access to the Internet for more than 8 hours

Looking at  BGP (Border Gateway Protocol) updates from Gambian ASNs around the time of the outage, we see a clear spike at 01:10 UTC. These update messages are BGP signaling that the Gambian ASNs are no longer routable.

How The Gambia lost access to the Internet for more than 8 hours

It is important to know that BGP is a mechanism to exchange routing information between autonomous systems (networks) on the Internet. The routers that make the Continue reading

An Application-Layer Approach To Multi-Cloud Network Fabrics

This post was originally published on the Packet Pushers’ Ignition site on September 21, 2021. It sounds trite to say that enterprise IT environments are multi-cloud, but the extent of cloud heterogeneity might shock those not paying attention. A recent survey found that 44 percent of organizations had more than half of their workloads deployed […]

The post An Application-Layer Approach To Multi-Cloud Network Fabrics appeared first on Packet Pushers.

Recursive BGP Next Hops: an RFC 4271 Quirk

All BGP implementations I’ve seen so far use recursive next hop lookup:

  • The next hop in the IP routing table is the BGP next hop advertised in the incoming update
  • That next hop is resolved into the actual next hop using one or more recursive lookups into the IP routing table.

Furthermore, all BGP implementations I’ve seen used multiple recursive next hops (if available) to implement load balancing toward the BGP next hop – that’s how we made EBGP load balancing work in Stone Age of networking.

Read more …

Recursive BGP Next Hops: an RFC 4271 Quirk

All BGP implementations I’ve seen so far use recursive next hop lookup:

  • The next hop in the IP routing table is the BGP next hop advertised in the incoming update
  • That next hop is resolved into the actual next hop using one or more recursive lookups into the IP routing table.

Furthermore, all BGP implementations I’ve seen used multiple recursive next hops (if available) to implement load balancing toward the BGP next hop – that’s how we made EBGP load balancing work in Stone Age of networking.

Read more …

New Year, New Us?

It’s been a while, hope all are well. This is a behind the scenes update to share with you what has been going on with us at NC and where we are headed. Short story, we’ve taken a break but are getting back to it with new content, new ideas, and quite a few changes. If you want a heads up on what is coming, give this episode a listen. If you like surprises, well just ride it out and you’ll see soon enough. It’s good to be back.

The post New Year, New Us? appeared first on Network Collective.

BGP in 2021 – The BGP Table

At the start of each year, I have been reporting on the behaviour of the inter-domain routing system over the past 12 months, looking in some detail at some metrics from the routing system that can show the essential shape and behaviour of the underlying interconnection fabric of the Internet.

When quantum computers forget: Overcoming decoherence

There’s no point in having a quantum computer if it’s not smokin’ fast; otherwise it’s way too much trouble, what with all the subzero temperatures and instability and such. So it’s always newsworthy when somebody sets a new standard for quantum computing processing speeds, even if quantum computers are far from common commercial use.In this case that somebody is IBM, which recently announced its newly developed quantum computing processor, called Eagle, has broken the 100-qubit barrier. IBM[Get regularly scheduled insights by signing up for Network World newsletters.] Fusion boldly (if clumsily) says it views Eagle “as a step in a technological revolution in the history of computation.” (It sounds like an algorithm wrote that sentence! Is this where you’re leading us, Big Blue? A quantum future of incoherent techspeak?)To read this article in full, please click here

When quantum computers forget: Overcoming decoherence

There’s no point in having a quantum computer if it’s not smokin’ fast; otherwise it’s way too much trouble, what with all the subzero temperatures and instability and such. So it’s always newsworthy when somebody sets a new standard for quantum computing processing speeds, even if quantum computers are far from common commercial use.In this case that somebody is IBM, which recently announced its newly developed quantum computing processor, called Eagle, has broken the 100-qubit barrier. IBM[Get regularly scheduled insights by signing up for Network World newsletters.] Fusion boldly (if clumsily) says it views Eagle “as a step in a technological revolution in the history of computation.” (It sounds like an algorithm wrote that sentence! Is this where you’re leading us, Big Blue? A quantum future of incoherent techspeak?)To read this article in full, please click here

Splitting files on Linux by context

The csplit command is unusual in that allows you to split text files into pieces based on their content. The command allows you to specify a contextual string and use it as a delimiter for identifying the chunks to be saved as separate files.As an example, if you wanted to separate diary entries into a series of files each with a single entry, you might do something like this.$ csplit -z diary '/^Dear/' '{*}' 153 123 136 In this example, "diary" is the name of the file to be split. The command is looking for lines that begin with the word "Dear" as in "Dear Diary" to determine where each chunk begins. The -z option tells csplit to not bother saving files that would be empty.To read this article in full, please click here

Splitting files on Linux by context

The csplit command is unusual in that allows you to split text files into pieces based on their content. The command allows you to specify a contextual string and use it as a delimiter for identifying the chunks to be saved as separate files.As an example, if you wanted to separate diary entries into a series of files each with a single entry, you might do something like this.$ csplit -z diary '/^Dear/' '{*}' 153 123 136 In this example, "diary" is the name of the file to be split. The command is looking for lines that begin with the word "Dear" as in "Dear Diary" to determine where each chunk begins. The -z option tells csplit to not bother saving files that would be empty.To read this article in full, please click here

Tello Drone — Initial Review and Python Programming

What is this about ?

A small starter programmable drone that is meant for mostly indoor and has 80 grams of weight with a flight time of 13 minutes.

Some Highlights

https://www.ryzerobotics.com/tello

– Small Drone with under 100 grams weight
– Suitable for kids and anyone who is starting out to get into drones and programmable ones
– Two sites (Tello and tello.edu) offers various addons to support learning and make it more customised for learning
– 13 minutes of Flight time
– 100m Flight distance
– 720p HD Transmission
– 2 Antennas
– you can also have VR headset compatibility
– In collab with DJI and Intel
– Operation via various Apps (Paid and Free ones), Programming Languages ( we are interested in this)

Fancy Features

– Throw and Go — you can just toss Tello into the air
– 8d Flips (needs battery more than 50%)
– Bounce mode (flies up and down from your hand)

Things that I didn’t like :

-First and foremost, there is no way this connects to your home Wifi, Drone goes into an AP Broadcast mode (meaning this starts broadcasting its own AP and we have to connect to it)

This Continue reading

Quality is (too often) the missing ingredient

Software Eats the World?

I’m told software is going to eat the world very soon now. Everything already is, or will be, software based. To some folks, this sounds completely wonderful, but—leaving aside the privacy issues—I still see an elephant in the room with this vision of the future.

Quality.

Let me give you some recent examples.

First, ceiling fans. Modern ceiling fans, in case you didn’t know, don’t rely on the wall switch and pull chains. Instead, they rely on remote controls. This is brilliant—you can dim the light, change the speed of the fan, etc., from a remote control. No unsightly chains hanging from the ceiling.

Well, it’s brilliant so long as it works. I’ve replaced three of the four ceiling fans in my house. Two of the remote controls have somehow attached themselves to two of the three fans. It’s impossible to control one of the fans without also controlling the other. They sometimes get into this entertaining mode where turning one fan off turns the other one on.

For the third one—the one hanging from a 13-foot ceiling—the remote control sometimes operates one of the other fans, and sometimes the fan its supposed to operate. Continue reading

Designing WhatsApp

 

This is a guest post by Ankit Sirmorya. Ankit is working as a Machine Learning Lead/Sr. Machine Learning Engineer at Amazon and has led several machine-learning initiatives across the Amazon ecosystem. Ankit has been working on applying machine learning to solve ambiguous business problems and improve customer experience. For instance, he created a platform for experimenting with different hypotheses on Amazon product pages using reinforcement learning techniques. Currently, he is in the Alexa Shopping organization where he is developing machine-learning-based solutions to send personalized reorder hints to customers for improving their experience.

Problem Statement

Design an instant messenger platform such as WhatsApp or Signal which users can utilize tosend messages to each other. An essential aspect of the application is that the chat messageswon’t be permanently stored in the application.

FUN FACT: Some of the chat messengers such as FB Messenger stores the chat messages unless the users explicitly delete it. However, instant messengers such as WhatsApp don’t save the messages permanently on their server.

Gathering Requirements

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