RU2745031C1 - A method for modeling the processes of functioning of a communication network taking into account the impact of destabilizing factors - Google Patents

Abstract

FIELD: computing.SUBSTANCE: invention relates to the field of computing. The technical result is achieved due to proactive reconfiguration, the decision on which is made on the basis of analysis and processing of data of qualitative indicators of equipment (technical basis) used at the physical, channel, network levels, determination of the optimal parameters of equipment.EFFECT: increased stability of the communication network, taking into account the impact of destabilizing factors.1 cl, 2 dwg

Description

The invention relates to the field of modeling communication systems and can be used to study the qualitative characteristics of equipment used on a communication network, as well as to determine the stability properties of a communication network.

Methods for modeling communication systems are now known.

Known "A method for modeling an accident, diagnostics and recovery of a complex technological structure and an information system for its implementation", RF patent №2252453, G06N 1/00, publ. 05/20/2005, bull. No. 14, which consists in determining the circuit characteristics of elements of a complex technological structure (STS) and establishing their interconnection. All connections between the elements of the STS schematic diagram are divided into main and backup. An arbitrary combination of damage to the CTS elements is set and the value of the accident rate of the state of connections between CTS elements is determined. In the case of inequality of the specified indicator to zero, the CTS is restored to work, changing it by replacing damaged links with backup ones through active actions of the operator. Determine the value of the indicator of recovery of the CTS performance and develop a forecast of the state of the changed CTS. The system ensures that the operator receives operational information on actions to restore the CTS operability based on the use of the existing reserve of the CTS internal capabilities, the development of a CTS state forecast and recommendations for improving the functioning of the modified CTS.

The disadvantages of this method is the relatively low stability of the functioning of the STS with the possible impact on it of destructive influences.

The closest in technical essence and functions performed by the analogue (prototype) to the claimed is a method of modeling the processes of ensuring the technical readiness of communication networks during technical operation [Patent 2336566 Russian Federation, IPC G06N 1/00 (2006.01). A method for modeling the processes of ensuring the technical readiness of communication networks during technical operation and a system for its implementation. Grechishnikov E.V., Pominchuk O.V., Ivanov V.A., Belov A.S., Karelin D.A., Drozdov A.S .; applicant and patentee State educational institution of higher professional education Academy of the Federal Security Service of the Russian Federation (Academy of the Federal Security Service of Russia). - 2006143248/09, app. 06.12.2006; publ. 20.10.2008, bul. No. 29. -17 s.].

The prototype method consists in the following sequence of actions. Determine the schematic characteristics of the elements of a communication network (SS), establish their interconnections, describe the structure of the SS, divide all connections into primary and backup, set arbitrary combinations of damage to the elements of the SS network, determine the values of the accident rate of the state of connections between SS elements, simulate the process of ensuring technical readiness when operating the SS, simulate various types of failures, damages and failures of the main elements of the SS, replace the damaged links with reserve ones, determine the value of the indicator of recovery of the SS operability, collect statistics, predict the technical state of the main SS elements and calculate the main indicators of SS functioning.

The disadvantages of the prototype method is the relatively low stability of the functioning of the SS when exposed to destabilizing factors (VDF) on its structural elements. This is due to the fact that SS reconfiguration is performed without simultaneously taking into account the structural and flow characteristics (normalized values of equipment parameters) of the SS with VDF at the physical, channel, network level relative to the reference model of interconnected open systems (EMVOS). Under the influence of a destabilizing factor, one should understand the impact on the telecommunication network, the source of which is a physical or technological process internal or external to the telecommunication network, leading to the failure of network elements.

When considering the composition of telecommunication equipment of any typical communication center, it is possible to highlight the availability of equipment that supports modern transport technologies WDM, SDH, IP. The equipment operating on the above technologies can be divided into levels relative to the EMVOS, for example: the equipment operating on the WDM technology operates at the physical level. Equipment operating according to SDH technology - at the link level. Equipment operating on IP technology - at the network level.

At present, the issues related to the functioning of the SS with the use of the above technologies at each separate level of EMVOS are widely and fully covered. However, the issues of the functioning of the SS taking into account the VDF in aggregate at three levels (physical, channel and network) were not considered. In this case, a scientific and technical problem arises, the essence of which lies in the fact that the functioning of the SS equipment at each level proceeds separately with the fulfillment of the requirements for stability, but when they are combined, the stability indicator does not meet the requirements.

The proposed method allows you to assess the process of functioning of the SS, taking into account the VDF at three levels in the complex.

The analysis of the prior art made it possible to establish that analogs characterized by a set of features identical to all features of the claimed solution are absent, which indicates that the claimed method meets the "novelty" condition of patentability.

The search results for known solutions in this and related fields of technology in order to identify features that match the distinctive features of the prototype features of the claimed method have shown that they do not follow explicitly from the prior art. The prior art also did not reveal the influence of the transformations envisaged by the essential features of the claimed invention on the achievement of the specified technical result. Therefore, the claimed invention meets the "inventive step" requirement of patentability.

The "industrial applicability" of the method is due to the presence of an element base, on the basis of which devices that implement this method can be made.

The technical problem to be solved by the proposed method is the lack of known solutions aimed at determining the main parameters of the equipment operating at three levels of the EMVOS SS in the complex, in order to develop requirements for the parameters (characteristics) of the equipment necessary for the stable functioning of the SS, taking into account the VDF ...

The aim of the invention is to increase the stability of the communication network, taking into account the impact of destabilizing factors. This will allow you to set the required quality indicators for the equipment while ensuring that the stability requirements for the communication network are met.

This goal is achieved by the fact that the proposed method for modeling the processes of the functioning of the communication network taking into account the influence of destabilizing factors, which is characterized by the fact that, first, during the technical operation of modeling the processes of the functioning of the SS, taking into account the VDF, they describe the structure of the communication network, simulate the process of ensuring technical readiness during the operation of the SS, simulate various types of failures, damage and failures of the main elements of the SS, additionally set the parameters of the equipment of the physical, channel, network level as initial data, criteria for assessing the stability of the network's functioning at the physical, channel, network level, determine the number of implementation of modeling the processes of ensuring the technical readiness of the communication network at the physical, channel and network level, simulate the processes of ensuring the technical readiness of the communication network at the physical, channel and network levels, after modeling the processes of ensuring technical readiness at at the physical level, measurements of the parameters of the equipment operating at the physical level are carried out, the correspondence of the measured values to the specified criterion values is checked, if the values of the measured parameters do not correspond to the required values, then procedures for localizing faulty elements are carried out in case of failure of the SS functioning at the physical level, messages are sent to the SS elements about the state of health SS elements at the physical level, reconfiguring SS on serviceable elements of the physical layer equipment, restoring SS elements, repeat the steps to simulate the processes of ensuring technical readiness at the physical level and check the correspondence of the measured values of the equipment parameters to the specified criterion values, if the measured parameters of the physical layer equipment correspond to the specified criterion values, then proceed to modeling the process of technical readiness at the channel level, after modeling the processes of providing technical readiness at the channel level, measurements of the parameters of the equipment operating at the channel level are carried out, the correspondence of the measured values to the specified criterion values is checked, if the values of the measured parameters do not correspond to the required values, then procedures for the localization of faulty elements are carried out in case of failure of the SS functioning at the channel level, messages are sent to the SS elements about the state of serviceability of the SS elements at the channel level, reconfiguring the SS on serviceable elements of the channel level equipment, restoring the SS elements, repeat the steps to simulate the processes of ensuring technical readiness at the channel level and check the correspondence of the measured values of the equipment parameters to the specified criterion values, if the measured parameters of the channel level equipment correspond given criterion values, then they proceed to modeling the process of technical readiness at the network level, after modeling the processes, technical readiness at the network level is carried out, the parameters of the equipment operating at the network level are measured, the correspondence of the measured values to the specified criterion values is checked, if the values of the measured parameters do not correspond to the required values, then procedures for the localization of faulty elements are carried out in case of failure of the SS at the network level, messages are sent to the elements SS on the state of serviceability of SS elements at the network level, reconfiguring SS on serviceable elements of the network level equipment, restoring SS elements, repeat the steps to simulate the processes of ensuring technical readiness at the network level and check the correspondence of the measured values of the equipment parameters to the specified criterion values, if the measured parameters of the network equipment levels correspond to the specified criterion values, then the results of the parameters of the equipment of the physical, channel network layer are output.

The claimed method is illustrated by drawings:

fig. 1 is a block diagram of a method for modeling the processes of functioning of a communication network, taking into account the impact of destabilizing factors;

fig. 2 - time diagram of the SS functioning taking into account the VDF.

It is proposed to implement the claimed method in the form of a sequence of actions shown in FIG. one.

Block 1 sets the initial data for modeling the communication network. The initial data are:

- a fragment of a communication network, typologically invariant to a real fragment of a communication network;

- parameters of equipment of the physical, channel, network level;

- criteria for assessing the stability of the network functioning at the physical, channel, network level;

n is the number of impacts of destabilizing factors on the elements of the communication network at the physical, channel, network level;

m is the number of impacts of destabilizing factors on network elements at the physical, channel, network level in accordance with the parameters;

S is the number of streams received at the SS level;

t ₁ - duration of measurement of SS parameters of the physical, channel, network layer;

t ₂ - the duration of processing the parameters of the physical, channel, network layer of the SS;

t ₃ - the duration at which the faulty elements of the SS are determined;

t ₄ - the duration at which the serviceable elements of the SS are determined;

t ₅ - the duration of the change in the topological structure of the SS;

t ₆ - the duration of processing the parameters for compliance with the quality characteristics of the elements of the SS;

t ₇ - duration of restoration of SS elements at the physical, channel, network level;

t ₈ - duration of functioning in a normal state;

_Тн is the duration of the SS being in a faulty state;

T _neisr is the average value of the duration of the SS being in a faulty state;

T _isr - the average value of the duration of the SS in good condition;

K _id - the coefficient of the correct operation of the SS at the physical, channel, network levels;

R _vdf - the probability of the impact of the functioning of the elements of the SS at VDF;

P _ij is the parameter of the equipment quality indicator, where i is the index indicating the type of technology; j - index designating the parameter of the i-th type of technology;

POSNR - quality parameter of physical layer equipment - signal-to-noise ratio;

K _{fec -} quality parameter of physical layer equipment - FEC coefficient (%);

K _osh - quality parameter of link-level equipment - error rate;

T _z - quality parameter of link layer equipment - packet delay time;

T _var.z - quality parameter of link level equipment - packet delay variation time;

К _пп - quality parameter of link level equipment - packet loss coefficient;

T _{S + 1} - duration when the next stream (signal, message) arrives at the physical, channel, network layer of the SS;

T _ogr is the duration of limiting the flow of flows to the physical, channel, network layer of the SS;

P (t) is the probability of SS recovery;

T _rest is the duration of the SS recovery.

In block 2, the number of realizations of modeling the processes of ensuring the technical readiness of the communication network at the physical, channel and network levels is determined.

In block 3, the processes of ensuring technical readiness at the physical level are simulated.

Block 4 simulates various types of damage failures, failures of the main elements of the SS at the physical level.

In block 5, measurements are made of the quality parameters of the equipment functioning at the physical level.

In block 6, the correspondence of the measured values to the specified criterion values at the physical level is checked, if the values of the measured parameters do not correspond to the required values, then they go to block 7.

In block 7, procedures are performed for localizing faulty elements in case of failure of the SS functioning at the physical level.

In block 8, messages are sent to the SS elements about the state of health of the SS elements at the physical level.

In block 9, the SS is reconfigured on the serviceable elements of the physical layer equipment.

In block 10, the CC elements are restored, then the process is repeated in steps 3, 4, 5 in accordance with FIG. one,

if the measured parameters of the physical layer equipment correspond to the specified criterion values, then proceed to modeling the process of technical readiness at the channel level,

after modeling the processes of ensuring technical readiness at the channel level, measurements of the quality parameters of the equipment operating at the channel level are carried out, the correspondence of the measured values to the specified criterion values is checked, if the values of the measured parameters do not correspond to the required values, then procedures for the localization of faulty elements are carried out in case of failure of the SS functioning at the channel level ,

sending messages to the SS elements about the state of health of the SS elements at the link level,

reconfiguration of the SS on serviceable elements of the link level equipment,

recovery of the CC elements, then the process is repeated in steps 12, 13, 14 in accordance with FIG. one,

if the measured parameters of the physical layer equipment correspond to the specified criterion values, then proceed to modeling the process of technical readiness at the network layer,

after modeling the processes of ensuring technical readiness at the network level, measurements of the quality parameters of the equipment operating at the network level are carried out, the correspondence of the measured values to the specified criterion values is checked, if the values of the measured parameters do not correspond to the required values, then procedures for the localization of faulty elements are performed in case of failure of the SS at the network level ,

sending messages to the SS elements about the state of health of the SS elements at the network level,

reconfiguring SS on serviceable elements of network layer equipment,

recovery of the CC elements, then the process is repeated in steps 21, 22, 23 in accordance with FIG. one,

if the measured parameters of the network layer equipment correspond to the specified criterion values, then go to the stage of outputting the results of the parameters of the physical, channel network layer equipment.

Based on the collection of data on the functioning of the SS, taking into account the VDF, the state of the main elements of the network at various stages of operation is predicted and its main indicators are calculated: K _id is the coefficient of good operation, P (t) is the probability of recovery, T _rest is the duration of recovery of the SS.

The number of realization (runs) of the model (N) is determined:

where P is the value of the prior probability, which can be determined by preliminary tests on the model;

- значение аргумента функции Лапласса, при котором вероятность попадания случайной величины

в интервал (-t_α,t_α) равна α;

is the value of the argument of the Laplace function at which the probability of hitting a random variable

in the interval (-t _α , t _α ) is equal to α;

;ε -precision of the estimate, equal to

;

- оценка математического ожидания, полученная в результате моделирования;

- an estimate of the mathematical expectation obtained as a result of modeling;

М (х) - mathematical expectation of the required parameter;

α is the reliability of the estimate.

, а для нормального распределения выражением:

.The user load is set in the form of the flow rate λ _m and the law of its distribution F _λ (t). For example, for a Poisson (simplest) flow, the distribution law is given by the expression:

, and for a normal distribution by the expression:

...

The number of VDF (n), the number of VDF according to the correspondence of parameters (m), the number of streams (S) are set.

Block 2 simulates the arrival of the flow F (t) for the transmission of messages at intervals of duration T _{S + 1} . During the functioning of the SS, which meets and fulfills the requirements of the model duration, the value T _{cfS is taken} . The intervals of durations τ between the arrival of signals in the simplest flow are distributed exponentially with the distribution function F (t) = 1-e ^-λτ , the distribution density распределения (t) = λe ^-λτ , where λ> 0 is the distribution parameter representing the flow intensity VDF.

The intervals of the durations of the flow at the input of the system are equal to the duration of the previous cycle of operation T _cfS .

In block 3, the network interfaces are identified and the software is loaded for equipment operating at the physical level with the duration of measuring the parameters of the SS elements (t ₁ ).

In block 5, the correspondence of the parameters, the characteristics necessary for the normal operating state of the equipment for the duration of the processing of the parameters at the physical level of the SS (t ₂ ) is read.

. При появлении отказа функционирования элементов СС на физическом уровне, система переходит в режим поиска неисправности (локализация отказов) блок 9. При нормальном функционировании системы переходит в блок 13.In block 7, when a flow arrives with a duration of t ₂ , the incoming flow (F (t ₂ )) is compared for the presence of the absence of the probability of the VDF level P _wdf , which is distributed according to the normal exponential law

... When a failure occurs in the functioning of the SS elements at the physical level, the system goes into the troubleshooting mode (localization of failures) block 9. During normal operation of the system, it goes into block 13.

In block 13, the quality of the parameters, the characteristics when servicing the physical layer of this received information flow is checked.

With a satisfactory result, the flow enters block 15, where the main processes take place in comparison with the required level parameters.

.When the flow F (t) arrives with the duration of the quality parameters processing at the physical level of the SS, the probability of compliance with the parameters will be equal to P _ij . and is distributed according to the normal law

...

If at least one indicator of the parameter of the physical level does not correspond to the normative values of the serviceable state of the SS element, then it is necessary to take a number of measures to restore the operability of the SS elements (block 17):

- to determine the reason for the change in quality characteristics (parameters) at the physical level;

- change the quality characteristics (parameters) of the SS elements at the physical level with the spent recovery time t ₆ ;

- restore the elements of the SS for the duration t ₇ .

At the end of the recovery measures, carry out control measurements of the quality characteristics (parameters) of the physical layer of the SS in order to ensure the reliability of the restoration of the functioning of the elements of the SS of the physical layer. In the future, the process goes to block 19, which is necessary to enter the mode of normal (required) SS functioning at the physical level and determine the final simulation time.

If the value of the quality characteristics (parameters) does not correspond to the required ones, then in block 9 and 10 the fault localization mode in case of failure of the SS functioning and identifies the operable SS elements by means of signal exchange between the SS elements.

After processing the streaming signals in block 9 and 10 in block 11, a number of measures are taken to reconfigure the structure of the SS on the serviceable elements of the SS:

the type of malfunction is determined for the time T _n ;

analysis, diagnostics, assessment of the state of the SS elements are performed, at which the main tasks of the network could be performed in time t ₄ ,

the topological, streaming structure of the SS changes during the reconfiguration time t ₅ .

In the future, if all the qualitative indicators of the characteristics (parameters) of the physical layer correspond to the normative values of the serviceable state of the elements of the SS, then the functioning of the SS of the model taking into account the VDF is completed and the process of the cycle functioning is closed.

The output results of the state of functioning of the physical level of the elements of the SS, taking into account the VDF, are the durations of the serviceable (T _and ) and faulty (T _n ) network operation, which are further used in calculating the coefficient of serviceable action or the availability of the SS.

When carrying out calculations using the proposed methods and software applications, graphical time diagrams for assessing the functioning of the SS, taking into account the VDF of the physical layer, were obtained (Fig. 2).

The proposed method and the realizing modeling system ensure the elimination and expansion of the functionality of technical solutions with the provision of simulated operation of the SS taking into account the VDF, calculating the coefficient of good operation and comparing it with the required values of the stability properties of the SS.

Thus, due to the above operations, a technical result is achieved, the presented scientific and methodological support is the basis for the development of an approach and scientific and technical proposals for identifying technical requirements for equipment operating at the SS at the physical level, taking into account the VDF when planning and deploying a communication network.

Claims (1)

A method of modeling the processes of functioning of a communication network taking into account the impact of destabilizing factors, which consists in the fact that they describe the structure of a communication network, simulate the process of ensuring technical readiness during the operation of a communication network, simulate various types of failures, damage and failures of the main elements of a communication network, characterized in that set the parameters of equipment of the physical, channel, network levels as initial data, criteria for assessing the stability of the functioning of the network at the physical, channel, network levels, determine the number of implementation of modeling the processes of ensuring the technical readiness of the communication network at the physical, channel and network levels, simulate the processes of ensuring technical readiness communication networks at the physical, channel and network levels, after modeling the processes of ensuring technical readiness at the physical level, they measure the parameters of equipment operating at the physical level, check the appropriate of the measured values to the specified criterion values, if the values of the measured parameters do not correspond to the required values, then perform procedures for localizing faulty elements in the event of a failure of the SS functioning at the physical level, sending messages to the SS elements about the state of health of SS elements at the physical level, reconfiguring the SS on serviceable elements of the physical equipment. level, restoration of SS elements, repeat the steps to simulate the processes of ensuring technical readiness at the physical level and check the correspondence of the measured values of the equipment parameters to the specified criterion values, if the measured parameters of the equipment of the physical level correspond to the specified criterion values, then proceed to modeling the process of technical readiness at the channel level, after modeling the processes of ensuring technical readiness at the channel level, measurements of the parameters of the equipment operating at the channel level are carried out f, the correspondence of the measured values to the specified criterion values is checked, if the values of the measured parameters do not correspond to the required values, then procedures are performed for localizing faulty elements in the event of a failure of the SS functioning at the link level, sending messages to the SS elements about the state of health of the SS elements at the channel level, reconfiguring the SS in serviceable elements of the equipment of the link level, restoration of SS elements, repeat the steps to simulate the processes of ensuring technical readiness at the link level and check the correspondence of the measured values of the equipment parameters to the specified criterion values, if the measured parameters of the equipment of the link level correspond to the specified criterion values, then proceed to modeling the process of technical readiness on network level, after modeling the processes of ensuring technical readiness at the network level, measurements of the parameters of equipment operating on the networks are carried out level, check the correspondence of the measured values to the specified criterion values, if the values of the measured parameters do not correspond to the required values, then perform procedures for localizing faulty elements in case of failure of the SS at the network level, sending messages to the SS elements about the state of health of SS elements at the network level, reconfiguring the SS on serviceable elements of the network level equipment, restoration of the SS elements, repeat the steps to simulate the processes of ensuring technical readiness at the network level and check the correspondence of the measured values of the equipment parameters to the specified criterion values, if the measured parameters of the network level equipment correspond to the specified criterion values, then the results of the parameters of the physical equipment are output , channel, network levels.

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