What is BGP? Protocol behind Facebook outage explained, DNS meaning and Cloudflare report of networking error

Facebook, Instagram and WhatsApp all went down for several hours on Monday night.

The social media platforms were taken down by a protocol outage which not only brought them to a halt but also cost shareholders a lot of money.

The outage, combined with a whistleblower interview, saw Facebook’s share price tumble 4.9% - costing CEO Mark Zuckerberg $6 billion personally.

Here’s all you need to know about the Facebook outage, what BGP and DNS mean, and an expert’s take on what happened through Cloudflare…

What is BGP?

BGP (Border Gateway Protocol) is one of the key mechanisms behind how the internet works, alongside the DNS (Domain Name System).

In essence, DNS is the address book and BGP the roadmap for the internet, helping people navigate the vast mesh of connected networks that make up the internet to help them find the website they want and then the quickest route to it.

What caused the Facebook outage?

Facebook said the problem had been caused by a configuration change to the “backbone routers” that coordinate traffic between the firm’s data centres.

This caused the cascading effect which brought the company’s various services down.

Cloudflare, a web infrastructure and security firm, said Facebook had, through a series of updates on Monday and seemingly accidentally, told the BGP that the paths for everything Facebook runs were no longer there – meaning people could no longer find a way to the social network.

Experts have said this is most likely to have been caused by a software bug in the updates or human error, although some have noted Facebook did not rule out foul play being the cause of the incident in its statement – however, there is currently no evidence to suggest that that is the case.

Why did it take so long to fix?

It appears that the problem not only took down the social media platforms, but everything Facebook runs, including its own internal systems – with reports that staff were locked out of offices as internet-connected keycard entry systems went down, and were also unable to access their internal communications platform.

As a result, it was hard for staff to initially diagnose and coordinate on resolving the problem.

There were even reports in the US of Facebook having to send a team to one of its data centres to reset the servers manually to fix the issue.

One expert also noted that ongoing social distancing measures because of the pandemic and remote working may have also played a part.

Software testing expert, Adam Leon Smith of BCS, The Chartered Institute for IT, said: “It is unlikely the issues were directly caused by people working from home, however it is quite possible that it took so long to restore the service because of reduced staffing within the data centre.

“This would compound the problem because the nature of the failure meant that remote access to the data centre was also unavailable.”

Can anything be done to prevent this from happening again?

This latest incident, after the major outages linked to Cloudflare in 2020 and Fastly earlier this year will again highlight the potential problems with having large portions of the internet reliant on just a handful of large companies and where one small issue can bring down huge segments of online services.

There are currently no obvious solutions to this, but this latest outage is likely to reignite the debate around internet infrastructure.

For many individuals and businesses too, the incident showed just how much they depend on Facebook and its services not just to communicate, but also to log in to other platforms.

In response, people have been encouraged to consider using other credentials beyond their Facebook log-in details to access other online services.

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