Just after 1200 UTC on Tuesday, June 7, the Africa-Asia-Europe-1 (AAE-1) and SEA-ME-WE-5 (SMW-5) submarine cables suffered cable cuts. The damage reportedly occurred in Egypt, and impacted Internet connectivity for millions of Internet users across multiple countries in the Middle East and Africa, as well as thousands of miles away in Asia. In addition, Google Cloud Platform and OVHcloud reported connectivity issues due to these cable cuts.
The impact
Data from Cloudflare Radar showed significant drops in traffic across the impacted countries as the cable damage occurred, recovering approximately four hours later as the cables were repaired.
It appears that Saudi Arabia may have also been affected by the cable cut(s), but the impact was much less significant, and traffic recovered almost immediately.
In the graphs above, we show that Ethiopia was one of the impacted countries. However, as it is landlocked, there are obviously no submarine cable landing points within the country. The Afterfibre map from the Network Startup Resource Center (NSRC) shows that that fiber in Ethiopia connects to fiber in Somalia, which experienced an impact. In addition, Ethio Telecom also routes traffic through network providers in Kenya and Djibouti. Djibouti Telecom, one of these providers, in turn peers with larger global providers like Telecom Italia (TI) Sparkle, which is one of the owners of SMW5.
In addition to impacting end-user connectivity in the impacted countries, the cable cuts also reportedly impacted cloud providers including Google Cloud Platform and OVHcloud. In their incident report, Google Cloud noted “Google Cloud Networking experienced increased packet loss for egress traffic from Google to the Middle East, and elevated latency between our Europe and Asia Regions as a result, for 3 hours and 12 minutes, affecting several related products including Cloud NAT, Hybrid Connectivity and Virtual Private Cloud (VPC). From preliminary analysis, the root cause of the issue was a capacity shortage following two simultaneous fiber-cuts.” OVHcloud noted that “Backbone links between Marseille and Singapore are currently down” and that “Upon further investigation, our Network OPERATION teams advised that the fault was related to our partner fiber cuts.”
When concurrent disruptions like those highlighted above are observed across multiple countries in one or more geographic areas, the culprit is often a submarine cable that connects the impacted countries to the global Internet. The impact of such cable cuts will vary across countries, largely due to the levels of redundancy that they may have in place. That is, are these countries solely dependent on an impacted cable for global Internet connectivity, or do they have redundant connectivity across other submarine or terrestrial cables? Additionally, the location of the country relative to the cable cut will also impact how connectivity in a given country may be affected. Due to these factors, we didn’t see a similar impact across all of the countries connected to the AAE-1 and SMW5 cables.
What happened?
Specific details are sparse, but as noted above, the cable damage reportedly occurred in Egypt – both of the impacted cables land in Abu Talat and Zafarana, which also serve as landing points for a number of other submarine cables. According to a 2021 article in Middle East Eye, “There are 10 cable landing stations on Egypt’s Mediterranean and Red Sea coastlines, and some 15 terrestrial crossing routes across the country.” Alan Mauldin, research director at telecommunications research firm TeleGeography, notes that routing cables between Europe and the Middle East to India is done via Egypt, because there is the least amount of land to cross. This places the country in a unique position as a choke point for international Internet connectivity, with damage to infrastructure locally impacting the ability of millions of people thousands of miles away to access websites and applications, as well as impacting connectivity for leading cloud platform providers.
As the graphs above show, traffic returned to normal levels within a matter of hours, with tweets from telecommunications authorities in Pakistan and Oman also noting that Internet services had returned to their countries. Such rapid repairs to submarine cable infrastructure are unusual, as repair timeframes are often measured in days or weeks, as we saw with the cables damaged by the volcanic eruption in Tonga earlier this year. This is due to the need to locate the fault, send repair ships to the appropriate location, and then retrieve the cable and repair it. Given this, the damage to these cables likely occurred on land, after they came ashore.
Keeping content available
By deploying in data centers close to end users, Cloudflare helps to keep traffic local, which can mitigate the impact of catastrophic events like cable cuts, while improving performance, availability, and security. Being able to deliver content from our network generally requires first retrieving it from an origin, and with end users around the world, Cloudflare needs to be able to reach origins from multiple points around the world at the same time. However, a customer origin may be reachable from some networks but not from others, due to a cable cut or some other network disruption.
In September 2021, Cloudflare announced Orpheus, which provides reachability benefits for customers by finding unreachable paths on the Internet in real time, and guiding traffic away from those paths, ensuring that Cloudflare will always be able to reach an origin no matter what is happening on the Internet.
Conclusion
Because the Internet is an interconnected network of networks, an event such as a cable cut can have a ripple effect across the whole Internet, impacting connectivity for users thousands of miles away from where the incident occurred. Users may be unable to access content or applications, or the content/applications may suffer from reduced performance. Additionally, the providers of those applications may experience problems within their own network infrastructure due to such an event.
For network providers, the impact of such events can be mitigated through the use of multiple upstream providers/peers, and diverse physical paths for critical infrastructure like submarine cables. Cloudflare’s globally deployed network can help content and application providers ensure that their content and applications remain available and performant in the face of network disruptions.