Increasing the Reliability of a Heterogeneous Network using Redundant Means and Determining the Statistical Channel Availability Factor

Abstract

The purpose of the article is to develop recommendations for controlling the reliability of a communication network by introducing redundant facilities and using statistical data evaluation. Improving the reliability of communications is ensured through the use of redundant facilities that duplicate the most critical objects. The reliability indicator is the load route availability factor, which is represented by predefined sequences of interstation directional channels used to transmit information between two points (nodes) of the network, taking into account the type of load of the telecommunication channel. A reliability assurance scheme has been proposed, which is intended to develop an action plan aimed at preventing hazards or at least reducing their negative consequences. Monitoring of network reliability indicators will allow for conducting its dynamic control, and the use of backup facilities that duplicate the most critical facilities will eliminate possible consequences of danger.

Keywords

• 1 Reli-availability
• availability factor
• communication channel
• load route
• communication route
• between nodes
• communication network
• monitoring of reliability indicators

1. Introduction

Before considering reliability issues, it is necessary to recall the structure of a heterogeneous Telecommunication Network (TCN) [ 1–4 ]. The scheme of a full-fledged heterogeneous TCN is a three-level hierarchical sequence of multiplexers (Fig. 1).

The first level of multiplexing (compression) uses the separation of transmission channels by frequency, and time:

 k tl  k tl C = C i Cti  =  C i , ti  1 t1 1 t1 (1) where  i is the number of frequency intervals; ti is the number of time intervals; i is the number of a channel in order (non-negative integers).

The second level includes signals of different physical nature:

CII = f (E )m  Cf (E )i , f (E )1 f (E )i = f (E )1, f (E )m , (2) where f ( E ) is the number of energy channels. i

2. Research Results

The reliability of the components of a heterogeneous telecommunication network is understood as the ability to maintain over time within the established limits the values of all parameters that characterize the ability to perform the required functions in the specified modes and conditions of use, maintenance, storage, and transportation [ 5 ].

The reliability scheme is shown in Fig. 2.

The suggested scheme is designed to develop an action plan aimed to prevent hazards or at least reduce their negative consequences. Short-term hazard forecasting is performed to alert the public and collect data. These data are used in long-term forecasting, which in turn is used to assess risks and their permissible levels to declare the safety of facilities, make decisions on their location and operation, develop measures to prevent accidents, and prepare for response to them. The list of protection measures includes: • Use of materials and structures resistant to a particular hazard. • Hazard interception involves shielding the facility or its most vulnerable and critical elements from the hazard, or shielding the hazard from the facility, as well as counteracting the hazard. • Replacement of maintenance systems (power supply, ventilation, air conditioning, fire alarm, fire extinguishing, warning, etc.). • Reconfiguration of the communication network by redistributing resources [ 7, 8 ]. • Alternative routing (call re-routing), in which traffic includes at least one node not involved in the previously selected route [ 9 ].

Reconfiguration/re-routing can be performed by load balancing, in which the task of establishing communication is distributed among several network devices. This is done, in particular, to optimize resource utilization, reduce request service time, and horizontal cluster scaling (dynamic addition/removal of devices) [ 10–12 ].

Elimination of hazards is ensured through the use of backup facilities that duplicate the most critical facilities. It should also be noted that the use of monitoring of network reliability indicators is effective, allowing conducting their dynamic control [ 13–15 ].

The purpose of the paper is to develop recommendations for controlling the reliability of a communication network by introducing redundant facilities and using statistical data evaluation. Increasing the reliability of communications is ensured through the use of redundant facilities that duplicate the most critical objects.

Reliability is the feature of an object to maintain over time within the established limits the values of all parameters that characterize its ability to perform the required functions in the specified modes and conditions of use, maintenance, storage, and transportation.

Reliability is one of the components of an object’s functional stability. Fig. 3 shows that the components of functional sustainability are reliability, survivability, and fault tolerance.

The indicators of the functional sustainability components are considered by the following groups: 1. Reliability indicators. 2. Indicators of survivability. 3. Indicators of fault tolerance.

Reliability Vitality

Fault tolerance Functional stability

This paper will focus on the reliability property of an object.

It is indicated that reliability is a complex feature that, depending on the purpose of the object and the conditions of its use, may include reliability, durability, maintainability, and preservation or certain combinations of these properties. It is also indicated that this term is used only for a general non-quantitative description of these properties [ 5 ].

One of the parameters for quantifying this reliability is the time between failures [ 16 ]. The quantitative indicator of reliability, and availability, use the term “time to failure of the telecommunication channel”—Time to Failure (TTF).

The statistical channel availability factor for a certain period of observation time t is calculated by the formula [ 16–18 ]: kch ( t ) =

TTFch

TTFch + TTRch

, t  0 , (4) where TTF + TTR is the considered time interval; TTR is the time-to-repair (time to restore the telecommunication channel performance).

TTRch can be calculated by the formula [ 19 ]: TTRch = TTR01 + TTR12 + TTR23 , (5) where TTR01 is the time interval from the failure to its detection (undetected fault time), for example, in the case of a latent failure; TTR12 is the time interval during which maintenance is prepared (maintenance support performance). TTR12 is characterized by a certain time interval of logistic delay (including delivery of parts and tools; delivery, installation, or calibration of measuring instruments; the arrival of specialists; the processing of technical documentation; delivery registration; waiting for transportation; delay due to unacceptable environmental conditions, etc.), including administrative delays (time interval of waiting for logistics resources, which does not include delivery of spare parts); TTR23 is an active repair time.

By the type of load, the unified communication network is divided into technological and corporate (production and economic) networks [ 21 ]. The technological segment of the network includes the means of an automated dispatch control system: a complex of remote control and data collection; a subsystem of automatic frequency and power control; a complex of control and optimization of electrical modes; a complex of dispatch simulator; a complex of equipment repair scheduling and coordination procedures. The corporate segment of the network includes organizational and economic management; production and economic management; operational and dispatching and operational and technological management (voice information); repair and maintenance of facilities [ 22–31 ].

3. Conclusions

When calculating the availability factors of communication channels, load routes, and the communication network, statistical data have been used. By entering the sequence of operations for calculating availability factors and the conditions for monitoring network reliability indicators, dynamic control of the network can be performed.

Increasing the reliability of communications is ensured through the use of redundant facilities that duplicate the most critical facilities. The reliability indicator is the load route availability factor, which is represented by predefined sequences of interstation channels used to transmit information between two points (nodes) of the network, taking into account the type of telecommunication channel load.

4. References

[1]

V. Buriachok, et al., Invasion Detection Model using Two-Stage Criterion of Detection of Network Anomalies, in: Workshop on Cybersecurity Providing in Information and Telecommunication Systems, vol. 2746 (2020) 23–32.

References

[2] S. Gnatyuk , et al, New Secure Block Cipher for Critical Applications: Design, Implementation, Speed and Security Analysis , Advances in Intelligent Systems and Computing , vol. 1126 ( 2020 ) 93 - 104 . doi: 10 .1007/978-3- 030 -39162- 1 _ 9

[3] P. Anakhov , et al., Increasing the Functional Network Stability in the Depression Zone of the Hydroelectric Power Station Reservoir , in: Workshop on Emerging Technology Trends on the Smart Industry and the Internet of Things , vol. 3149 ( 2022 ) 169 - 176 .

[4] V. Grechaninov , et al., Decentralized Access Demarcation System Construction in Situational Center Network , in Workshop on Cybersecurity Providing in Information and Telecommunication Systems II , vol. 3188 , no. 2 , 2022 , pp. 197 - 206 .

[5] Statestandard of Ukraine 2860-94 . Reliability of equipment. Terms and definitions (in Ukrainian) .

[6] P. Anakhov , et. al., Evaluation Method of the Physical Compatibility of Equipment in a Hybrid Information Transmission Network , J. Theor. Appl. Inf. Technol . 100 ( 22 ) ( 2022 ) 6635 - 6644 .

[7] Industry guidance document 34.20 . 507 - 2003 . Technical operation of electrical stations and networks . Rules (in Ukrainian).

[8] S. Sulima , Methods of Reconfiguration of Basic Network Computing Resources Based on Virtualization Technology: Diss. ... Candidate Technical Sciences: 05.12.02 “Telecommunication Systems and Networks”. Kyiv: 2019 (in Ukrainian).

[9] Recommendation ITU-T Q . 12 ( 11 / 1988 ). General Recommendations on telephone switching and signalling. International automatic and semi-automatic working. Overflow-alternative routing-reroutingautomatic repeat attempt .

[10] Recommendation ITU-T Y . 2085 ( 06 / 2016 ). Next Generation NetworksFrameworks and functional architecture models. Distributed service networking service routing .

[11] I. Keslassy , et. al., Optimal LoadBalancing , INFOCOM 2005 24th Annual Joint Conference of the IEEE Computer and Communications Societies, Proceedings , 3 ( 2005 ) 1712 - 1722 . doi: 10 .1109/INFCOM. 2005 .1498452

[12] F. Li , et. al., Load Balancing Routing in Three Dimensional Wireless Networks , 2008 IEEE International Conference on Communications , 2008 , 3073 - 3077 . doi: 10 .1109/ICC. 2008 .578

[13] P. Vorobienko , L. Nikityuk , P. Reznichenko , Telecommunication and Information Networks , Kyiv: SUMMITKnyga , 2010 , 708 .

[14] M. Herlich , C. Maier , Measuring and Monitoring Reliability of Wireless Networks , IEEE Communications Magazine , 59 ( 1 ) ( 2021 ) 76 - 81 . doi: 10 .1109/ MCOM . 001 .2000250

[15] P. Anakhov , et. al., Stability Method of Connectivity Automated Calculation for Heterogeneous Telecommunication Network, CEUR Workshop Proceeding , 3188 ( 2021 ) 282 - 287 .

[16] ITU-T Recommendation G. 602 . Transmission media characteristics. Reliability and availability of analogue cable transmission systems and associated equipments .

[17] IEC 60870-4 : 1990 . Telecontrol equipment and systems. Part 4: Performance requirements .

[18] ITU-T Recommendation E. 862 ( 06 /92). Dependability planning of telecommunication networks .

[19] Public telecommunications network. Telephone network. Technical requirements (in three parts). Part 1. Principles of building a public telephone network . Kyiv: Administration of State Special Communications , 2015 . 129 p. (in Ukrainian) .

[20] Standard of the Organization of Ukraine National Energy Company “Ukrenergo” 35 .101:2018. General Technical Requirements for Automated Control Systems for Technological Processes of 220-750 k V substations of the unified energy system of Ukraine (in Ukrainian) .

[21] Transmission System Code ( 14 . 03 . 2018 , No. 309 ) (in Ukrainian) .

[22] IEC 61025 : 2006 . Fault tree analysis (FTA) . Second edition 2006 - 12 .

[23] B. Suo , et. al., Calculation of Failure Probability of Series and Parallel Systems for Imprecise Probability, Int. J. Eng. Manuf . 2 ( 2 ) ( 2012 ), 79 - 85 . doi: 10 .5815/ijem. 2012 . 02 .12

[24] IEC 61703 : 2016 . Mathematical Expressions for Reliability, Availability, Maintainability and Maintenance Support Terms .

[25] Standard of the Organization of Ukraine National Energy Company " Ukrenergo" 29.240 . 7 - 18 : 2021 . Planning and determination of the availability ratio of the transmission system. Part I. Overhead power lines (in Ukrainian) .

[26] Y. Kharazishvili , E. Dron, Forecasting of Indicators, Threshold Values and the Level of Economic Security of Ukraine in the Medium Term; Analytical Report . Kyiv: National Institute of Strategic Studies, 2014 , 117 .

[27] Methodology for calculating the level of economic security of Ukraine (approved by Order of the Ministry of Economy of Ukraine (2 . 03 . 2007 , No. 60 ) (in Ukrainian) .

[28] Y. Xin-She , Nature-Inspired Optimization Algorithms , Elsevier Inc. 2014 . doi: 10 .1016/C2013-0-01368-0

[29] ENTSO-E Continental Europe Operation Handbook . Policy 6: Communication Infrastructure . 14 .

[30] V. Mukhin , et. al., Protecting Hybrid Information Transmission Network from Natural and Anthropogenic Hazards, Int. J. Comput. Netw. Inf. Secur . 14 ( 5 ) ( 2022 ) 1 - 10 . doi: 10 .5815/ijcnis. 2022 . 05 .01

[31] Recommendation ITU-T E . 500 ( 11 /98) Traffic intensity measurement principles .