Why did the Internet blockade in the temporarily occupied territories become possible, what threats does it pose and how can Ukrainians protect themselves?, reports krymsos.
How the network works
Imagine a big river that fills with small streams. The architecture of the Internet is based on this principle. It is made up of many small networks called Autonomous Systems (ASs), which in turn can be Internet Service Providers (ISPs).
But no stream-network (AS) has a direct connection to all devices on the Internet, but only to devices on its network. As well as the beginning of the stream does not flow directly into the sea. This means that multiple ASs joining together in different physical locations make it possible to exchange information between different computers. These aggregation points are called Internet Exchange Points (IXPs).
Internet exchange points can provide ISPs with connections to Internet backbones, which are massive underground or submarine fiber optic cables used to transmit data over long distances.
Thus, subscribers of small local providers get access to the worldwide network through the channels of larger national or international backbone Internet providers. Their examples are given below.
On fig. 1 shows the RETN internet backbone and its data centers. Map from the RETN website
On fig. 2 shows the Internet backbone “DataGroup”. Map from DataGroup website.
On fig. 3 shows the Internet backbone “DataLine”. Map from the DataLine website.
On fig. 4 shows the Internet backbone “Eurotranstelecom”. Map from Eurotranstelecom website.
On fig. 5 shows the VEGA internet backbone. Map from the VEGA website.
On fig. 6 shows the location of Internet Exchange Points (IXPs). All Ukrainian IXPs are located in seven cities: Kyiv, Kharkov, Donetsk, Mariupol, Odessa, Lvov and Ivano-Frankivsk. Map from the TeleGeography website
Physical control over these important Internet connection points gives the possibility of control over the Internet in a region or a given country. This method of total digital censorship is used in China and Russia.
On fig. 7 shows a more detailed map of the main fiber optic data cables. Scheme from the website of the UN International Telecommunication Union (www.ITU.INT)
What happens after February 24 with the Internet and communications in the occupied territories
The Internet in Ukraine has been developing independently for a long time, the state practically did not interfere in this process. Unlike many countries in Western Europe, the industry was not regulated. We have a large number of traffic exchange points between local ISPs and competition from backbone providers – this has led to a natural excess “margin of safety” for the Ukrainian network infrastructure.
With the start of a full-scale Russian aggression in Ukraine, the Russian military could try to destroy all communication points in order to cut off the Internet for most of the country. But they cannot turn off a large number of small local ISPs, which often do not go beyond their localities or even individual areas of cities.
Since February 24, all interruptions in the operation of the telecommunications infrastructure in the Kherson region and the Zaporozhye region were the result of two aspects:
1) intentional jamming of radio signals (cellular network) in a limited area when a significant amount of military equipment and personnel of the armed forces of the Russian Federation are moving in order to impossibility of prompt transmission of information about this to the Armed Forces of Ukraine from local residents.
2) damage to the main traffic transmission channels during armed confrontation and artillery shelling.
If some communication channels were damaged as a result of shelling, traffic was redirected through the remaining ones, but this redundancy is also not infinite. Especially against the background of the impossibility of carrying out repair work on damaged lines. As a result, subscribers located in the territories temporarily occupied by Russian troops received low-speed Internet.
For several months, some media wrote that the Russian Federation was laying fiber-optic cables from the temporarily occupied territory of Crimea. As of May 30, the Russians have not yet been able to complete what they started.
When both mobile communications and broadband Internet access disappeared in the occupied territories. However, the Internet appeared at one of the local ISPs. According to information from the Twitter account of the global Internet monitor @netblocks, the traffic of the Skynet provider, as can be seen from the tracing of data packets, goes through the Russian Federation.