# The Architecture of the Access Protocols of the Global Infocommunication Resources +
## 1 Introduction  
This article is based on the materials of the report that was made by the authors at MICSES-2019 in December 2019 and published in proceedings of MICSES-2019 [1]. An important purpose of cyberspace is to support the ability of people and devices to access global infocommunication resources. Since the beginning of our century, there has been an appearance and growth in the number of different options for accessing infocommunication resources, due to the development of network infrastructure. Implementation of radio access to global infocommunication resources at the last mile according to [2] is carried out using a variety of multiple access procedures that allow rational use of a common channel resource limited by the spectrum of the radio channel. The wide range of access radio networks available to the terminal device at the last mile [2] made it possible for the terminal to refuse at any time and at any point in space from an already established network connection, and switch to using the resources of another access radio network that is more suitable for transmitting current traffic. Furthermore, the terminal device can simultaneously communicate with multiple radio networks of access and use of their network resources. The totality of all access networks available at a certain point in space, each of which can function using a particular radio technology, forms a heterogeneous broadcast network. In order to efficiently manage the available resources of a heterogeneous network, as well as to comply with the concept of Always Best Connected (ABC) [3], developers today use a Vertical Handover. Vertical Handover (VHO) [4] is a procedure for transmitting support for a terminal device traffic transfer session from one access radio network to another access radio network, regardless of the location of the device. Performing the vertical handover procedure in a heterogeneous network in practice requires solving several interrelated problems [5]:  
* Accumulation, consolidation, storage and analysis of all data required for making an informed decision about the vertical handover procedure;
* Selecting the appropriate access radio network from several currently available ones;
* Connecting the terminal device to the new radio network (without losing the existing communication session). The purpose of the study presented in [1] was to develop a centralized strategy for managing access to network resources at the stage of selecting the best radio network for access to infocommunication resources. The object of research is a set of all access radio networks available at the last mile to the terminal device, forming a heterogeneous terrestrial network. The subject of the research is mathematical models for evaluating the probabilistic and temporal characteristics of the process of transmitting user data in the radio network at the last mile. In [1], the following tasks were considered and solved, in particular:  
* Analysis of existing solutions used in practice to implement procedures for selecting a suitable access radio network;
* A new, centralized strategy for selecting the access radio network is proposed and a scenario for interaction between terminal devices, aggregating devices, and access radio networks is developed;
* Developed a mathematical model of the process of information interaction on the last mile in the case of using a centralized strategy and selecting a radio access network. The essence of the proposed strategy was that the architecture of a heterogeneous access network is supplemented by an aggregation device (AD) or otherwise an aggregator of access radio networks,which performs functions related to the centralized selection of the access radio network on the last mile. At the same time, access to global infocommunication resources is carried out in two steps:  
I--Select an access network. II--Transfer of user data. A mathematical model of step II was proposed.