After the Great Firewall of China, will Russia have its Internet Iron Curtain?

Russia carried out tests Monday to ensure the "security" of its internet infrastructure in case of a foreign cyberattack as part of measures that rights activists worry could also tighten censorship and lead to online isolation.

A controversial law that allows the country to cut internet traffic from international servers came into force in November, but the communications ministry has denied that the government is gearing up to isolate the Russian segment of the internet and said ordinary users would not notice the tests.

The ministry said that the drills are aimed at ensuring the "integrity" of the internet.

"The results of the tests have shown that on the whole both authorities and service providers are ready to effectively react to emerging risks and threats and ensure the reliable work of both the internet and the single telecommunication network," deputy communications minister Alexei Sokolov told reporters.

He said the results of the tests would be presented to President Vladimir Putin, and added that the drills would continue in the future.

State-controlled television channel Rossiya 24 said the authorities had in fact been conducting the tests for the past two weeks.

Apart from testing the safety of the Russian segment of the internet in case of an attack, authorities also tried to ensure the safety of mobile users and whether it was possible to intercept traffic and text messages, Sokolov said.

"The purpose of the task is to ensure the reliable operation of the internet in Russia in any conditions and under any circumstances," he added, referring to the drills.

"Our task is to make sure everything works. That's what today's drills are aimed at."

The law, which Putin signed in May, requires Russian internet providers to install equipment provided by the authorities to enable centralised control of data traffic.

They will also filter content to prevent access to banned websites.

Putin defends 'sovereign internet'

At his annual news conference last week, Putin defended Russia's internet policies, promising that the country was not "moving towards closing off the internet."

"A free internet and a sovereign internet are two concepts that aren't mutually exclusive," he said.

The internet is the country's main forum for political debate and opposing voices as well as coordinating opposition demonstrations.

The new system is set to go online in 2021.

Internet providers need to ensure before then that their networks have the technical means for "centralised traffic control" to counter potential threats.

The main providers have already begun installing the required equipment including the enabling of Deep Packet Inspection (DPI) which would allow Russia's Roskomnadzor internet watchdog to analyse and filter traffic.

Supporters of the legislation say the aim is to ensure Russian sites keep working if they are unable to connect to international servers or in the case of threats from abroad such as cyberattacks.

But rights activists say it is another censorship bid following previous efforts in Russia to block services such as the LinkedIn professional networking site and the Telegram messenger service.

While Beijing has created what has become known as the Great Firewall of China to filter content and limit access to foreign websites, activists and analysts are divided if Russia has the resources to implement such a system.