### Anatomy of a Digital Disappearance: BGP Data During the Venezuelan Blackouts

When the lights went out across Venezuela in the widespread blackouts of 2019, the country was plunged into darkness and silence. While the immediate focus was on the failure of the power grid, a parallel crisis was unfolding in the digital realm. For network engineers and internet observers around the globe, the story of the blackout was written in the language of the Border Gateway Protocol (BGP), the very system that underpins the global internet. The anomalies observed were a stark, real-time reflection of a nation’s infrastructure collapsing.

#### What BGP Tells Us

To understand the significance of these events, one must first grasp what BGP is. Think of it as the internet’s postal service. It’s the protocol that allows different networks—known as Autonomous Systems (AS)—to tell each other which IP addresses they can reach. When Venezuela’s primary state-run telecommunications provider, CANTV (AS8048), announces its routes via BGP, it’s essentially telling the rest of the world, “I have a path to these millions of users and services; send your traffic for them through me.”

When the power goes out, the routers that make these announcements go silent. Their BGP sessions with international peers time out, and just like that, a massive chunk of the country’s internet presence vanishes from the global map.

#### The Observed Anomalies

During the March 2019 blackout, network monitoring organizations observed a dramatic and sudden change in BGP activity originating from Venezuela.

**1. Massive Prefix Withdrawal:**
The most striking anomaly was a precipitous drop in the number of advertised BGP prefixes. On March 7th, 2019, data showed that Venezuela’s connectivity to the global internet dropped by as much as 90%. CANTV, the largest player, saw nearly all of its advertised network routes withdrawn from the global routing table. This wasn’t a subtle change; it was the digital equivalent of an entire continent falling off the map. Graphs from internet analysis firms showed a cliff-edge drop, indicating a catastrophic, simultaneous failure across the country’s core network infrastructure.

**2. Route Flapping:**
In the hours and days that followed the initial outage, observers noted significant “route flapping.” This occurs when network routes are announced and withdrawn in rapid succession. This pattern is often indicative of network instability—routers rebooting as power flickers back on, only to lose power again moments later. Each time a router came online, it would try to re-establish its BGP sessions and announce its routes, briefly appearing on the internet before vanishing once more. This flapping created instability not just within Venezuela, but also for the global networks trying to connect to it.

**3. The Disappearance of Key Autonomous Systems:**
While CANTV was the most significant, other smaller Venezuelan ASes also went dark. The BGP data allowed analysts to see precisely which networks were down and which, if any, had managed to stay online, likely through backup power like diesel generators. This provided a granular view of the outage’s scope, revealing that it was not isolated to one provider but was a systemic, nation-wide failure affecting the vast majority of the country’s digital infrastructure.

#### The Human Story Told by Data

These BGP anomalies were more than just technical data points on a chart. Each withdrawn prefix represented thousands of users, businesses, hospitals, and families being cut off from the world. The inability to communicate, access online banking, or get information from outside sources was a direct consequence of the BGP-level disconnection.

The Venezuelan blackouts served as a powerful case study in the fragility of our interconnected world. It demonstrated how deeply our digital lives are tied to physical infrastructure like the power grid. For network observers, the BGP data provided a raw, unfiltered view of a national crisis as it happened, telling a story of collapse, instability, and the silent scream of a country’s internet going dark.