According to the security director of telecom operator Elisa, the undersea cable that was damaged at the weekend will be repaired as soon as the weather conditions improve.
Estonian damage to the communication cable between Finland and Finland has practically no effect on the operation of communication connections, says the security director of the telecom operator Elisa Jaakko Wallenius.
A malfunction was detected in the undersea communication cable owned by Elisa between Saturday and Sunday. Elisa said on Tuesday that the disruption has no effect on its customers or services.
The fault in the cable was discovered at the same time as the damage in the gas pipeline between Finland and Estonia. The Central Criminal Police suspects that the gas pipe was probably damaged on purpose. Both Finland and Estonia are investigating whether the damage to the telecommunications cable and the gas pipe has anything other than a temporal connection.
Telecommunications systems are built in such a way that they consist of several different parts and connections, which verify each other if one part is damaged. Elisa also has several different ways to verify the operation of its international telecommunication connections.
“Every once in a while it happens that a fault occurs in one of the systems and the connection is lost. That’s why networks and international connections are built in such a way that possible failure situations are taken into account.”
On the weekend the broken cable was a spare cable, i.e. no communication connection was solely dependent on it. In data networks, such verifying connections are constantly on, and if a data transmission connection goes out of service, for example due to a device failure, the communication is automatically redirected to one of the verifying connections, Wallenius says.
“The capacities of the different connections are measured in such a way that a fault situation can occur, and it does not hinder data transfer.”
Wallenius does not reveal in more detail what kinds of connections Elisa has at her disposal. Regarding submarine cables, however, Elisa uses its own cables as well as those owned by others.
Submarine cables typically have multiple users. For example, many telecommunication operators use the same connections in the same way as, for example, mobile phone network base stations. Wallenius does not comment on which other operators may have used the cable owned by Elisa that was damaged over the weekend.
Merenalaisten damage to communication cables is not exceptional.
“These are not terribly common, but every few years cables are damaged,” says Wallenius.
Usually, the problems are caused by the failure of the ground equipment connected to the cables. In sea areas, on the other hand, ships that have made an emergency anchor can cut the cable if the anchor does not stop but drags along the seabed.
“Then compensation is sought from the person who caused the damage to repair the cable,” says Wallenius.
For example, in 2009, the communication cable between Finland and Sweden broke down, when the Viking Line cruise ship Rosella hit it with its anchor. At that time, internet connections slowed down throughout Finland for several days.
Today, a single cable break would probably not cause a similar situation.
“The networks are built in advance to withstand disruptions,” says Wallenius.
Elisa intends to repair the broken communication cable as soon as the weather conditions improve, Wallenius says.
In practice, the ends of the broken cable are raised from the seabed and a length of cable is connected between the ends.
“It requires good weather conditions and getting a repair ship to the spot. However, the cable has to be lifted up from the sea, and repairing it requires special skills,” says Wallenius.
Estonian Defense Minister Hanna Pevkur said on Tuesday that the point of failure of the damaged communication cable has “very likely” been located. According to him, the damaged spot is located in Estonia’s economic zone at a depth of about 70 meters. According to the Finnish authorities, it is not right next to the gas pipe damage, but “in the same geographical area”.
Wallenius doesn’t have anything more detailed to say about the damage site either.