RU2573267C2 - Method for comparative evaluation of information computer network structures - Google Patents

Abstract

FIELD: information technology.

SUBSTANCE: method further includes specifying a set of M service control nodes; after receiving response messages from the service control nodes, selecting and storing identifiers and addresses of service control nodes, as well as a plurality of L messaging routes, followed by calculating the critical ratio of previously stored "hazardous" and "safe" nodes $$p_i^l$$

for each of the lth messaging routes between a subscriber and all service control nodes, where information exchange is impossible in information computer networks, for which the initial ratio of "hazardous" and "safe" nodes p^l is calculated, and the value thereof is consecutively increased by a value Δp until a condition is satisfied, where information exchange between a subscriber and service control nodes of information computer networks is impossible; selecting from the formed plurality of L messaging routes, routes with the maximum value $$p_i^l$$

to all available service control nodes of information computer networks from said subscriber, followed by selecting therefrom the messaging route for which the route length is minimal.

EFFECT: high reliability of results of comparative evaluation of information computer networks structures in conditions exposed to random and deliberate interference by forming alternative routes to service control nodes included in the information computer network structure and determining a safer route.

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Description

The invention relates to the field of information security of information and computer networks (IVS) and communication systems and can be used in a comparative assessment of the structures of an IVS for their resistance to failures caused by the effects of random and deliberate interference.

There is a method of providing adjustment of routes to network subscribers, implemented in the "Method of adjusting routes in the data network" according to the patent of the Russian Federation No. 2220190, IPC H04L 12/28, publ. 10/10/1998

The method consists in the fact that the search for message delivery routes to the subscriber is carried out at the network address of the switching node of its current binding. The choice of routes to the subscriber is carried out at the switching nodes by an official corrective message containing the network addresses of the subscriber, the switching node and the code of the sign of adjustment “record”, “erase”.

The disadvantage of this method is the lack of adaptation to changes in the structure of the communication network. This is because the adjustment of the implementation of routes is decentralized and does not cover the entire communication network, but its individual local sections. The lack of options for choosing routes to the subscriber often leads to the choice of a route of poor quality.

There is also known a method of selecting a route in the IVS, implemented in the "Method for choosing the expediently used route in the router for uniform distribution in the switching network" according to the application for the invention of the Russian Federation No. 2004111798, IPC H04L 1/00, publ. 05/10/2005

The method consists in pre-setting the initial data containing the quality criteria of the routes. The information about the structure of the communication network, including the addresses of the network nodes and the presence of communication between them, is stored in the router. Form a set of possible communication routes. After receiving the message for the target network address, one route is selected in accordance with the predefined criteria for the quality of routes and messages are sent along the selected route.

The disadvantage of this method is the relatively low stealth of communication when using the selected route of information exchange of subscribers in the communication network. The presence of transit network nodes with a low level of security creates the prerequisites for interception by cybercriminals of the information exchange of network subscribers.

The known method of comparative assessment of the network structure, implemented in the "Method of comparative assessment of the structure of the ITT" according to the patent of the Russian Federation No. 2331158, IPC H04L 12/28, publ. 08/10/2008

The method consists in preliminarily setting the parameters of the IVS and forming its topological scheme, calculating a comprehensive safety indicator for each node of the IVS. Connected to the IVS of subscribers, which form messages including the addresses of subscribers and their identifiers. The generated messages are transmitted, received, the identifiers and addresses of the subscribers are allocated and stored from the received messages, and information about the existence of communication between the subscribers and the IVS nodes through which information is exchanged is stored and stored. Using the results obtained, the most secure routes in the IVS are selected from the totality of all possible communication routes between the subscribers and the safe routes are brought to the IVS subscribers.

The disadvantage of this method is the relatively low reliability of the results of a comparative assessment of the structures of the IVS with an increase in the number of communication nodes. The low reliability is due to the large time and resource costs necessary to obtain initial data on a large number of TDF nodes, a decrease in the sensitivity of the route safety index, due to the fact that with an increase in the number of TDF nodes, the number of routes with a similar value of the route safety index will increase.

In addition, the method has a narrow scope, since it does not provide for adaptation of the route to changes in the structure of the IVS.

для каждого j-го варианта подключения абонентов, при котором смежные «опасные» узлы образуют цепочки, исключающие обмен между абонентами. Для этого выбирают случайным образом из каждого ранее запомненного варианта подключения абонентов p^j часть узлов из общего их количества и запоминают их как «опасные». Из смежных «опасных» узлов формируют связанные цепочки и запоминают их, последовательно увеличивают долю «опасных» узлов на величину Δp и повторяют формирование связанной цепочки до выполнения условий $$p^j=p_k^j$$

. Ранжируют альтернативные варианты подключения абонентов ИВС по значению величины $$p_k^j$$

и выбирают из них вариант с максимальным значением $$p_k^j$$

.Closest to the technical nature of the proposed method is a method of comparative assessment of the structures of the IVS according to patent RU No. 2408928, IPC G06F 12/14, H06F 12/22, publ. 01/10/2011, bull. No. 1. The method consists in the following steps. Alternative routes of message packets for each pair of alternative connections to the IVS of subscribers are extracted and stored from the topological scheme of the IVS. The value of the complex safety indicator PK _{i of the} i-th IVS node is compared, where i = 1, 2, 3, ..., with a predetermined minimum acceptable value of P _min . According to the results of the comparison, the node is remembered as “dangerous” or as “safe”. The critical ratio of “dangerous” and “safe” nodes is calculated $$p_k^j$$

for each j-th option of connecting subscribers, in which adjacent “dangerous” nodes form chains that exclude exchange between subscribers. To do this, randomly select from part of each previously stored subscriber connection option p ^j part of the nodes from the total number of nodes and remember them as “dangerous”. Connected chains are formed from adjacent “dangerous” nodes and stored, sequentially increase the share of “dangerous” nodes by Δp and repeat the formation of a connected chain until conditions are met $$p^j=p_k^j$$

. Alternate options for connecting IVS subscribers by value $$p_k^j$$

and choose from them the option with the maximum value $$p_k^j$$

.

The disadvantage of the prototype method is the relatively low reliability of the comparative assessment of the IVS structures, due to the lack of inclusion of service control nodes in the IVS structure, which, when exposed to random and deliberate interference, leads to the emergence of alternative routes with the same safety metrics from one subscriber to several service control nodes and, accordingly, to increase in time and resource costs when determining a safe route.

The purpose of the claimed technical solution is to develop a method for the comparative assessment of IVS structures, providing increased reliability of the results of a comparative assessment of IVS structures under the influence of random and deliberate interference due to the formation of alternative routes to the service control nodes included in the IVS structure and determining a safer route, taking into account failure forecasting its nodes.

для каждого l-го маршрута передачи сообщения между абонентом и всеми узлами управления сервисами, при котором невозможен информационный обмен в ИВС, для чего вычисляют первоначальное соотношение «опасных» и «безопасных» узлов p^l и последовательно увеличивают его на величину Δp до выполнения условия, при котором невозможен информационный обмен между абонентом и узлами управления сервисами ИВС. Затем выбирают из сформированного множества L маршрутов передачи сообщений маршруты с максимальным значением $$p_{к}^l$$

ко всем имеющимся узлам управления сервисами ИВС от данного абонента. После чего выбирают из них тот маршрут передачи сообщений, у которого значение длины маршрута минимально.This goal is achieved by the fact that in the known method of comparative assessment of the structure of the IVS, which consists in preliminarily setting the parameters of the IVS and forming its topological scheme, calculating a comprehensive safety indicator P _K for each node of the IVS, connecting to the computer network of subscribers who form messages including the addresses of subscribers and their identifiers, transmit the generated messages, receive them, set the minimum acceptable value of a comprehensive safety indicator P _min for the node s of the computer network and compare the value of the complex safety indicator P _{Ki of the} i-th IVS node, where i = 1, 2, 3, ..., with the pre-set minimum permissible value of P _min and with P _Ki <P _min remember the i-th node as “dangerous”, otherwise, at П _Ki ≥П _min , the node is remembered as “safe”, an additional set of M service control nodes is taken into account, which is taken into account when forming the topological scheme of the IVS. After receiving response messages from service control nodes, identifiers and addresses of service control nodes, as well as a set of L message transmission routes, where l = 1, 2, 3, ..., and information on the existence of communication between the subscriber and the IVS service control nodes are allocated and stored. After that, the critical ratio of previously stored “dangerous” and “safe” nodes is calculated $$p_{\mathrm{to}}^l$$

for each l-th message transmission route between the subscriber and all service control nodes, in which information exchange in the IVS is not possible, for which the initial ratio of “dangerous” and “safe” nodes p ^{l is} calculated and successively increased by Δp until the condition is met, in which information exchange between the subscriber and the IVS service control nodes is impossible. Then, routes with the maximum value are selected from the generated set L of message transmission routes $$p_{\mathrm{to}}^l$$

to all available IVS service management nodes from this subscriber. Then they select the message transmission route from which the value of the route length is minimal.

Thanks to the new set of essential features in the claimed method, the indicated technical result is achieved by forming alternative routes to the service control nodes included in the structure of the IVS and determining a safer route, taking into account the failure forecasting of the nodes included in it.

The claimed method is illustrated by drawings, which show:

in FIG. 1 is a diagram explaining the construction of the IVS under consideration;

in FIG. 2 is a flowchart of a method for comparative evaluation of IVS structures;

in FIG. 3 - correlation of the probability of the presence of information exchange between the subscriber and the service control nodes P _rm from the number of _TDF nodes on the message transmission route m.

The implementation of the claimed method is explained as follows.

At present, when considering the structure of modern IVS (telecommunication networks), taking into account the trends of their development, it is necessary to note the emergence of such an important component of the structure as service management nodes (information centers) [V.G. Olifer, N.A. Olifer. Computer networks. Principles, technologies, protocols (3rd edition), St. Petersburg. - 2009, p. 158]. The presence of service control nodes in the IVS structure requires the formation of a new approach for their comparative assessment, and especially under the conditions of random and deliberate interference.

At the same time, the growing role of service management nodes (information centers) is determined by the fact that they implement information services of the network. Two types of information can be stored in such centers: user information, that is, information that directly interests end users of the network; supporting service information to help the service provider provide services to users.

An example of information resources of the first type is web portals, on which a variety of reference and news information, information of electronic stores, etc. are located.

Information centers that store resources of the second type include, for example, various user authentication and authorization systems, with the help of which the organization owning the network checks the rights of users to receive certain services; billing systems, which in commercial networks calculate the fee for services received; user account information databases storing names and passwords, as well as lists of services that each user subscribes to [V.G. Olifer, N.A. Olifer. Computer networks. Principles, technologies, protocols (3rd edition). SPb. - 2009, p. 160].

Thus, taking into account the functional features of the service control nodes, in the IVS under the influence of random and deliberate interference, not only alternative routes between the subscriber and the service control node can be determined, but also alternative routes from this subscriber to other service control nodes providing identical network information services .

The implementation of the inventive method can be explained on the IVS diagram shown in FIG. one.

The IVS shown consists of a backbone network, access networks, service control nodes (information centers) and terminal equipment of subscribers [V.G. Olifer, N.A. Olifer. Computer networks. Principles, technologies, protocols (3rd edition). SPb. - 2009, p. 158]. The backbone network consists of routers 3, to which access networks and service control nodes are connected 4. Access networks, in turn, consist of switches 2 ₁ -2 _N , to which the terminal equipment of subscribers 1 _l -1 _{N is} connected. In this case, information exchange in the IVS with the construction of transmission routes is possible not only between subscribers 1 _l -1 _N , but also between subscribers 1 _l -1 _N and service control nodes 4. In the second case, the number of alternative routes for transmitting message packets increases significantly , which entails a decrease in the reliability of the results of a comparative assessment of the structures of temporary detention facilities under the influence of random and deliberate interference and, accordingly, an increase in the resource consumption of determining a safe route from the whole set yuschihsya alternative routes.

The block diagram of the algorithm for the comparative assessment of IVS structures is shown in FIG. 2.

At the initial stage, initial data is set (block 1, Fig. 2), including the number of subscribers 1, the number of network nodes (routers 3, switches 2 and service control nodes 4), the presence of communication lines between them, the security parameters of network nodes. Based on the source data, the initial topology of the IVS circuit is formed (block 2, Fig. 2). In addition, the minimum permissible value of the complex safety indicator P _{min is set} for the IVS nodes (block 3, Fig. 2). The value of P _{min is} set by directive, taking into account the implemented security functions, as regulated by GOST R ISO / IEC 15408-3-2002, Information Technology. Security methods and tools. Criteria for assessing the security of information technology. Part 3. Requirements of trust in security ”as the minimum level of trust in the equipment manufacturer. Experimental studies and the experience of operating the IVS showed that the value of P _min should be set in the range of 0.5 <P _min <1.

Then, a comprehensive safety indicator P _Ki is determined for each i-th IVS node (block 4, Fig. 2). Under the integrated indicator of the i-th, where i = 1, 2, 3, ..., of the IVS node _{Ki, we} mean the normalized numerical value of the convolution of security parameters characterizing the ability of the IVS node to withstand security threats. The calculation procedure P _Ki is known and described, for example, in the patent of the Russian Federation No. 2331158. Next, the value of the calculated complex safety indicator P _Ki (block 5, Fig. 2) is compared with a predetermined minimum acceptable value P _min . When P _Ki <P _{min, the} i-th node is remembered as “dangerous”, and otherwise, that is, when P _Ki ≥ P _min , the node is remembered as “safe” (block 6-7, Fig. 2).

Then, changes are made to the generated IVS scheme taking into account the obtained safety indicators (block 8, Fig. 2) and the subscribers are connected (block 4, Fig. 2), for which messages are formed, including the addresses of the subscribers and their identifiers. After this, the information exchange between subscribers and service control nodes is simulated (block 5, Fig. 2), as a result, many alternative routes for transmitting message packets L (block 11, Fig. 2) are determined.

для каждого l-го маршрута передачи сообщения из всех альтернативных маршрутов L (блок 14, фиг. 2).In the future, the initial ratio of “dangerous” and “safe” nodes p ^l is determined and a check is made for the presence of information exchange between the subscriber and the service control nodes (block 12-13, Fig. 2). If information exchange is possible, p ^{l is} increased by Δp. The value Δp is set based on the required accuracy of the calculation results in the range Δp = 0.01-0.2. After that, the current ratio of “dangerous” and “safe” service control nodes p ^l is determined (block 15, 17, Fig. 2). If the condition of impossibility of information exchange is fulfilled, the critical ratio of “dangerous” and “safe” nodes is determined $$p_{\mathrm{to}}^l$$

for each l-th route of message transmission from all alternative routes L (block 14, Fig. 2).

ко всем имеющимся узлам управления сервисами ИВС от данного абонента (блок 16, фиг. 2), которые соответствуют максимальному значению показателю безопасности без учета возможной тенденции увеличения воздействий. Учитывая необходимость прогноза воздействия случайных и преднамеренных помех на узлы ИВС, производится выбор безопасного маршрута из имеющихся альтернативных в соответствии с критерием, которым является минимальное значение длины (минимальное количество транзитов на маршруте). Определенный по данному критерию маршрут передачи сообщения запоминается и считается наиболее безопасным в данных условиях (блок 18, фиг. 2).Then the selection and storage of routes with the maximum value $$p_{\mathrm{to}}^l$$

to all available ICT service management nodes from this subscriber (block 16, Fig. 2), which correspond to the maximum value of the safety indicator without taking into account the possible trend of increased impacts. Given the need to predict the effects of random and deliberate interference on the IVS nodes, a safe route is selected from the available alternative ones in accordance with the criterion, which is the minimum length value (minimum number of transit routes). The message transmission route determined by this criterion is remembered and considered the most secure in these conditions (block 18, Fig. 2).

The feasibility of the implementation of the formulated technical result was tested by machine simulation on an IVS, consisting of 30 computers with well-known software (Microsoft Windows, Microsoft Office applications, Internet Explorer). Using modeling, the relationship between the probability of the presence of information exchange between the subscriber and the service control nodes P _rm from the number of nodes in the message transmission route m is obtained.

The achievement of the technical result is illustrated as follows. For the prototype method, the determination of the presence of information exchange between the subscriber and the service control nodes P _{1 was} carried out only taking into account the critical ratio of “dangerous” and “safe” nodes on the message transmission route. For the proposed method, the value of the presence of information exchange between the subscriber and the service control nodes P _{2 is} obtained taking into account the forecast of the impact of random and deliberate interference on the IVS nodes by determining the safe route from the available alternative ones in accordance with the minimum length value (minimum number of transit routes).

Moreover, the difference in the likelihood of information exchange between the subscriber and the service control nodes, taking into account the definition of a safe message transmission route under these conditions, has the greatest values in the range of 3-7 transit routers on the message transmission path (Fig. 3). The maximum difference was obtained at a value equal to 5 routers, which is the average value of the real number of transits on the transmission path of message packets with an IVS size of 1000 nodes [V.G. Olifer, N.A. Olifer. Computer networks. Principles, technologies, protocols (3rd edition). SPb. - 2009, p. 608-611] and is determined by the expression ΔP = P ₁ -P ₂ = 0.3, which is achieved by the formulated technical result when implementing the claimed method.

Thus, the claimed method, through the formation of alternative routes to the service control nodes included in the IVS structure and the determination of a safer route, taking into account the failure forecasting of the nodes included in it, allows increasing the reliability of the results of a comparative assessment of the IVS structures under the influence of random and deliberate interference.

Claims (1)

A method for a comparative assessment of the structures of an information and computing network, which consists in preliminarily setting the parameters of the information and computing network and forming its topological scheme, calculating a comprehensive safety factor P _K for each node of the information and computing network, connecting it to the information and computing network of subscribers, which generate messages, including the addresses of subscribers and their identifiers, transmit the generated messages, receive them, set the minimum acceptable value for meat indicator safety P _min for nodes of the computer network, and comparing the integrated safety index value P _Ki i-th node of the computer network, where i = 1, 2, 3, ..., with a predetermined minimum allowable value n _min, and when П _Ki <П _{min, the} i-th node is remembered as “dangerous”, otherwise, if П _Ki ≥ П _{min, the} node is remembered as “safe”, characterized in that they additionally specify a set of M service control nodes, which is taken into account when forming the topological information schemes On a computational network, after receiving response messages from service control nodes, identifiers and addresses of service control nodes, as well as a set of L message transmission routes, where l = 1, 2, 3, ..., and information on the existence of communication between the subscriber and control nodes are allocated and stored computer network services, after which the critical ratio of previously stored “dangerous” and “safe” nodes is calculated

for each l-th message transmission route between the subscriber and all service control nodes, in which information exchange in the information-computer network is impossible, for which the initial ratio of “dangerous” and “safe” nodes p ^{l is} calculated and subsequently increased by Δp to the fulfillment of the condition under which information exchange between the subscriber and the control nodes of the services of the information computer network is impossible, then, from the formed set of L routes for transmitting messages, the routes you with the maximum value

to all available nodes for managing services of an information-computer network from a given subscriber, after which they select the message transmission route for which the value of the route length is minimal.

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