Severe Internet and phone service outages hit Egypt and India Wednesday after two submarine cable communication lines were severed.
Submarine cable lines are the main connection lines for Internet service providers (ISPs) and telephony companies. The two lines that connect Egypt sit just off the coast of Alexandria. They were severed at approximately 6 a.m. local time. The accidents knocked out Internet connections throughout 70 percent of the country and international calls throughout 30 percent of the country, according to the Ministry of Communications and Information Technology.
India had nearly 50 percent of its capacity knocked offline, although its ISPs were able to reroute traffic through a backup system in the Pacific, said Vishal Sharma, principal consultant and technologist at Mountain View-based Metanoia, a communications consultancy firm.
The Line Lowdown
The accidents illustrate the importance of redundant systems, Sharma said. The most immediate solution is to use satellite technologies to reroute traffic. The problem, though, is the bandwidth capabilities are limited, making it an imperfect solution.
Instead, redundancy plans usually need to be in place while the initial lines are being laid. There are some private firms that specialize in laying cable, but typically submarine cables are laid by an international consortia consisting of ISPs, governments and other interested service providers since the cost is so steep.
The only way to ensure connectivity is to have two separate lines. The cables can be laid in two ways: pairs or rings.
Most major systems in the Atlantic and Pacific are pairs that contain two cable ducts, each which may contain a multitude of cables, Sharma said. The ISPs then either use one cable for all the traffic, keeping the second in reserve; or they can split capacity on each cable, re-routing to one cable in an emergency.
The other option is to lay the cable in a ring shape around a geographic region, connected nodes — such as Guam, Singapore and China — both to each other and the outer loop. This creates a networked configuration, which allows traffic to be re-routed through the loop if one node happens to be severed, Sharma said.
There has been no definitive answer for how the cables were cut. Initial reports of a ship’s anchor severing the lines appear erroneous as the lines were located two miles from each other, according to the government.
Egypt, along with other affected Arab nations, rushed a task force into place, searching for alternative means of communication as repairs to the two cables will likely take two weeks, according to the Ministry.