## 1 Introduction  
Rail transport occupies a significant position in Europe, offering the diversity of the infrastructure network. It provides a low-cost, long-term sustainable and especially ecological way of transporting passengers and goods practically over various long distances. Railways often become the main artery for the flow of freight and passenger traffic at the national and international level with gradual electrification, modernization, and construction. However, within transnational transport, railways become less flexible, and carriers have to overcome operational problems in the form of national interlocking systems for individual national railway infrastructure managers [1]. The European Union has established a single procedure to address these problems for all Member States by introducing a single European train control system--ETCS. This process began with the establishment of a core network of ETCS-equipped corridors across the countries of the European Union based on strategy papers. These corridors respect the network of TEN-T corridors that were established earlier. The unification of the signalingsystem will contribute to the operational interoperability and acceleration of traffic on these lines. Rail transport will become more competitive than other modes of transport. The individual stages of the ERTMS/ETCS track-side equipment are divided into the following application levels [2]:  
* L0--zero application level referred to as ETCS L0;
* L NTC--application level referred to as ETCS NTC;
* L1--first application level referred to as ETCS L1;
* L2--second application level referred to as ETCS L2;
* L3--third application level referred to as ETCS L3;
* L3 R--application level referred to as ETCS L3 Regional. The new ETCS system has both positive and negative effects on rail transport. Although it increases safety on railway lines where it is applied, it can also directly affect the permeability of railways. [PERSON] et al. [3] presented ERTMS system as a standard for railway across Europe and complex real-time system that guarantees safety at all times. [PERSON] [4] described the necessity of level-crossing safety in the ERTMS L2/3 operation context. In this paper, we examine and compare the impacts of the ETCS system on a selected section of the line using methods for calculating the practical throughput on ZSR lines [5]. A similar issue of applying ETCS L2 system to the main rail passenger lines was discussed in Danish infrastructure [6]. When we compare ETCS with the automatic block, we find that there are more problems with the practical throughput of the particular railway line sections equipped with ETCS. In the case of the practical throughput determination, the line (spatial) sections are assessed according to the braking distance, which can ultimately reduce the throughput. The principle of this problem is shown in Figure 1.  
ETCS application level 1 without additional means (Euroloop, in-fill radio) does not allow for achieving this line throughput as some modern national systems (CIR-ELKE2). The reason is the use of only point transmission of information between the track and vehicle part of the system. Additionally, during the deployment, vehicles or lines must be equipped with both systems (ETCS and national train protection), which increases costs. In this paper, we examine and compare the impacts of the ETCS system on a selected section of the line using methods for calculating the practical throughput on ZSR lines [7]. At the end of 2017, 4500 km of the main corridor network and more than 7000 vehicles equipped with the ETCS mobile unit were operational in accordance with ERTMS (European Rail Traffic Management System) [8]. European legislation is constantly implementing new directives and constantly amending older ones to make ERTMS an integral part of the European Railway Area. Directive 2017/6/EC set new targets for the deployment of ERTMS by 2023. This directive stipulates that 30-40% of the core network of corridors will be equipped in accordance with the ERTMS project.