RU2285348C2 - Method for finding solutions concerning possibility of connection between network elements - Google Patents

Abstract

FIELD: technology for determining solutions concerning possibility of connection between network elements using functions of network control system.

SUBSTANCE: in accordance to method, each network element contains input ports and output ports, while each provides a set of connection points. Connection possibility tables contains data about possible internal connections between connection points of any input port and any output port of any network elements, controlled by network control system. Method allows each time during selection of certain network element for use in a route with its input port and its output port to receive solution at network control device level concerning connection capabilities for certain network element.

EFFECT: increased searching efficiency at level of network control system.

2 cl, 5 dwg

Description

FIELD OF THE INVENTION

The present invention relates to the determination of solutions for the possibility of connecting network elements using the functions of a network management system that provides control of elements in a data network.

State of the art

Modern data transmission networks contain a huge number of network nodes (network elements), and a large number of nodes contain switching elements, such as cross connectors, containing a complex system of input and output ports. Each input and output port usually contains many connections and is characterized by various functions. For example, some output ports can be used to reset part of the signal, while other output ports provide end-to-end transmission of the input signal. Switching elements not only contain different types of ports and connections, but usually have certain equipment limitations so that not every input connector can work with an arbitrary output connector within the same or different switching elements of the network. There can be many reasons for such limitations, including differences in protocols used, physical characteristics, incompatible spatial locations, preferred or non-preferred connections, cost restrictions, etc.

To solve various problems associated with the search for expedient connections in modern networks, the following hierarchy of control systems is usually created and used:

a system (NMS) of network management of a network, wherein the SSU provides tracking of all network elements, that is, it contains information about the types of all existing network nodes and their connections at any current moment,

the system (EMS) for managing an element of a specific network element The EMS allows you to track one element, that is, it contains information about the various types of connections that the network element (node) contains, and about various equipment limitations of such a network element.

The SSA considers the network as the current configuration of network nodes and can contact any node by contacting its management system.

When it is required to find a route between two network points, the SSA uses a program, usually called a route identifier, designed to determine such a route between available network elements. After you find a preliminary route, which, for example, is defined as the shortest route, you should determine the detailed configuration of the connectivity through the elements planned for use in the route. To this end, the SSA refers to the SUE of each route node to search for specific solutions for connectivity.

A similar method is described in EP 1130942 A2, in which the network administrator requests a resource management mechanism for allocating an output port for an input port in an optical packet switching device. The resource management mechanism then accesses the database containing the availability parameters of the port of the switching element, and after reserving the free output port, it includes the optical switching control mechanism.

The successive, repeatedly repeated stages of the interaction between the SSE and each of the SEEs take considerable time, require multiple exchange of protocols. Sometimes a decision on the possibility of providing a connection for a particular node cannot be found due to any of its equipment limitations unknown to the SSA, and then a significant part of the route determination process needs to be repeated, that is, the number of search operations performed by the SSA in sequential, repeatedly repeated interaction with the EMS is increasing. As a result, the process requires even more time and is inefficient.

SUMMARY OF THE INVENTION

Thus, the present invention is directed to such a method for finding solutions for possible connections in a network containing a large number of switching network elements and SSAs, which allows efficient search at the SSU level.

SUMMARY OF THE INVENTION

To reduce the time required to find a solution for possible connectivity in network elements, an SSA (network management system) may contain a centralized database or a table of connectivity formed on the basis of databases of connectivity of components of many network elements. Each of the component connectivity databases can be copied from the management system (element management system) of the corresponding network element. In this case, the SSA will precisely “know” the structure of each network element.

In this application, the term SSA should be understood as a control object that provides control over a specific group of network elements that form a network or part of it.

In other words, an object of the present invention can be achieved by a method for finding solutions for connectivity for network elements to be included to form a route selected in a network managed by a network management system (CCS), in which each network element contains input ports and output ports, with each port providing multiple connection points; the method includes providing at the level of the network control table (TS (ST)) connectivity options containing data on possible internal connections between the connection points of any input port and the connection points of any output port in any network element controlled by the specified SSU, due to which there is always when a particular network element with its input port and its output port are supposed to be used in the route, it provides a solution for the possibility of connecting the specified specific network element at the SSU level.

The method also includes constant updating of the SSAs using the EMS of the respective managed network elements with any changes to the component connectivity tables, for example, regarding the availability of specific connection points.

However, to reduce the amount of memory required to write such a table to the SSA, the objective of the present invention can be achieved without obtaining information from the SSU of each specific network element by performing the following steps:

- classification of connection points of both input ports and output ports of all network elements in the form of a set of connection groups, designated 1, 2, 3 ... n, in which each of the groups is characterized by similar properties and / or restrictions,

- the assignment to each input port and each output port of a particular network element of one or more of these connection groups,

- formation of a table of connectivity options to present general rules on connectivity, indicating the possibility of forming a connection between any arbitrary group of connections from groups 1, 2, 3 ... n belonging to the input port of a network element, and any arbitrary group of connections from groups 1, 2 , 3 ... n, belonging to the output port of the network element, due to which, when choosing a particular network element for use on the route, with its input port and its output port always possible making decisions on connectivity for the specified specific network element at the SSA level by applying the connectivity rules to the connection groups assigned to the selected input and output ports.

It goes without saying that the above method is universal for any network elements controlled by SSA.

According to a preferred version of the method, it contains such a connection table (TC) arrangement that the rows of the table represent groups of 1, 2 ... n connections of input ports, the columns of the table represent groups of 1, 2 ... n connections of output ports, and each the intersection cell between a particular row and a specific column contains information about the possibility of an internal connection between a connection point belonging to a specified specific group of input ports and a connection point belonging to a specified conc group of output ports.

It should be emphasized that in the preferred embodiment of the present invention, the SSA does not need to know (contain) the connection capability structure of each network element (NE). Instead, it contains one relatively small connection capability table (TS) that is constructed to reflect the general connection capability rules network elements and, thus, effectively helps to determine the really applicable options for solutions according to the connection possibilities. It will be listed below.

In accordance with an additional, more elaborate version of the method, it contains:

- access to the SSA by specifying a specific network element with its input port and its output port required for the selected route, to obtain a decision on the possible connectivity for the specified network element,

- checking in the SSA which of the connection groups from the indicated groups 1, 2 ... n is present in the specified input port and which is in the specified output port,

- the application of the rules of connectivity by using the specified table (TS) connectivity in the SSA to determine whether the desired connection can be made between at least one group of connection groups of the input port and at least one group of connection groups of the output port

- in the case of confirmation of such a possibility, taking into account the decision on the determined connectivity, and

- appeal from the SSA to the network element management system (EMS) of a particular network element to activate a specific internal connection in the element,

- in the case of a negative decision result, transmission to the SSA a message that the decision on the possibility of connection is not defined for the indicated specified input port and specified output port of the SE.

The choice of the SE with its ports for the route can be performed, for example, using the Pathfinder program to determine the route that is part of the SSA. If a solution to the possibility of a connection is not found for the SE selected by Pathfinder, it should be informed accordingly.

The above variant of the method demonstrates that only work at a lower level (activation of the internal connection) is performed at the level of the network element, and there are practically no consecutive repeatedly repeated interaction steps for finding a solution from the element level (EMS) to the level of the SSA. Moreover, if a specific decision on the possibility of a connection between the input port and the output port of a particular network element (SE) was taken at the level of the SE, multiple data exchange would be required to iteratively search for a solution between the SEE and the SSE.

The problem of finding solutions for connectivity options for network elements can be almost completely solved at the level of the SSE, so that only the activation of the internal connection is left for the SSE level, due to the fact that at the SSU level all the information related to the connection groups associated with each a specific port in each SC, and all information on possible connection options between any "input" connection groups and any "output" connection groups.

The method, in particular the step of applying the rules for connection capabilities, may further comprise the step of indicating at the SSA level an internal connection between the contact point from the input connection group and the contact point from the output connection group, in which the specified input connection group and the specified output connection group are selected at the level SSO for a particular network element as a solution for connectivity.

The search for a solution for connectivity (either using a TS compiled from the corresponding tables of component connectivity, or using a TS of general rules for connectivity) can be completed by checking information about busy connections. In particular, it can be performed by first submitting to the SSU a database of busy connections and then accessing it (or the so-called hashed table XT (HT), which indicates the internal connections of network elements currently occupied. XT consists of many hashed sub-tables assigned to the corresponding network elements.Each hashed sub-table contains only a list of occupied internal connections of the element, and therefore is economical in terms of the occupied memory space, since there is no need to record the status of all possible real connections that can be established in the SC between all its input and output connection points.

When using the TS of the general rules of connectivity, the step of checking information on busy connections may include a preliminary presentation and subsequent access to a database designed to register the set of existing connection points in each connection group of a particular element; wherein the indication is performed after comparing the information about the existing connection points in the selected input and output connection groups with the information about the occupied connections.

For a more detailed explanation of the method should be given some information about the organization of the SSA. From the request in which the particular selected network element is indicated, the SSA obtains the designation of the input and output ports of the element. To this end, any SSA contains its topological information, preferably in the form of a network graph. As mentioned above, the SSA contains a table (TS) of connectivity, allowing you to make decisions about the availability of the possibility of creating an internal connection between the selected ports. The table (TS) of connectivity can be built on the table of connectivity of a component of managed network elements. In this case, the TS "knows" all the limitations of the connectivity points of these network elements and allows you to find solutions for connectivity at the SSU level.

According to a preferred embodiment of the present invention, the connection groups present on certain ports for any of the network elements controlled by the SSA are further described using topological information. If necessary, topological information may include registration of existing connection points in each connection group of any port of a managed network element. Although this information is quite detailed, it is far from complete information about the internal structure of the network element, as in some solutions of the prior art. The SSA Connectivity Capabilities (TS) table reflects the general connectivity rule that allows you to decide whether the selected ports (based on the connection groups that they contain) provide the ability to create an internal connection between them. In fact, such a connectivity table takes into account and summarizes all the limitations of the connectivity points known to managed network elements.

Based on the foregoing and in accordance with another aspect of the present invention, there is provided an improved network management system (CCS) comprising a connection capability manipulator (MS (CH)) unit, which allows determining at the SSU level a decision on connection capabilities for a particular network element, which should be included in the route selected in the network managed by the SSA, in which the connection capabilities manipulator contains a table (TS) of connection possibilities, which contains data on possible internal connections within any of the network elements managed by the specified SSA.

In one of the embodiments of the invention, the TS consists of databases of connectivity obtained from the EMS of the corresponding network elements.

In accordance with a preferred embodiment of the indicated SSA, the system comprises:

- modified topological data related to the network elements of the specified network and their ports, in which each input port and each output port of any network element, respectively, is assigned one or more groups of 1, 2, ... n connections for connection points so that each group compounds is characterized by similar properties and / or limitations, and

TS contains:

- general rules for connectivity, indicating the possibility of forming a connection between any arbitrary group of connections from groups 1, 2, 3 ... n, belonging to the input port of a network element, and any arbitrary group of connections from groups 1, 2, 3 ... n, the network element belonging to the output port, while the TS, thus, provides the possibility of determining in the SSD whether there is a solution for the possibility of connection in the specified network element, after receiving a request indicating a specific network element with a pair of input and yhodnogo ports required for use in the selected route.

The connectivity table (TS) is preferably constructed so that the rows of the table represent groups of 1, 2, ... n connections belonging to the input ports, and the columns of the table represent the groups 1, 2, ... n connections belonging to the output ports, and each intersection cell between a particular row and a specific column contains information related to the possibility of forming an internal connection between at least one connection point from the group of connections belonging to the input port of the network element, and at least about one connection point from the connection group that belongs to the output port of the specified network element.

If necessary, the connection capabilities manipulator in the SSA may contain a database of busy connections (the so-called hashed table) in the form of information chains, each of which indicates the internal connections that are currently occupied, in a particular network element. Each chain is designed for one busy connection, in which chains belonging to one network element form a hashed subtable of this element.

In the case when the TS is built for groups of contact points, the modified topological data may, if necessary, contain a database for registering the set of existing connection points in each connection group for each port of each specific element. To indicate a valid connection, the TS should provide the ability to compare information about existing connection points in the selected input and output groups of connections with information about busy connections.

In accordance with a third aspect of the present invention, there is also provided a computer program product that can be directly downloaded to an internal storage device of a digital computer, comprising pieces of program code for performing steps of the above method when said product is running on a computer.

A computer program product recorded on a recording medium used with a computer includes software readable by a computer, enabling the computer to control the functions of the network management system as described above.

Brief Description of the Drawings

The present invention can be further described below and illustrated by the following non-limiting drawings, in which:

figure 1 (prior art) presents a well-known structural block diagram illustrating the interaction between the SSA and the EMS for the task of determining solutions for connectivity;

figure 2 shows a structural block diagram illustrating the interaction between the SSA and the EMS for determining decisions on connectivity, in accordance with one embodiment of the present invention;

figure 3 schematically shows an example of a network element having input and output ports, and each port contains many groups of connections in accordance with the classification proposed in the present invention;

figure 4 shows an example table (TS) of the capabilities of the connection SSU in accordance with the present invention;

figure 5 shows an example of a hashed table (XT) in the SSA.

DETAILED DESCRIPTION OF THE INVENTION

Figure 1 shows a known type of interaction between the SSA and the TMN to determine the decision on the connectivity in the network element selected to form part of the route in the network (not shown). SSU (network management system) is indicated by number 10, contains a program for determining the route (indicated by number 12) and data on the network topology (indicated by number 14), which is usually constructed in the form of a graph that displays existing network elements, ports and layout of elements in the network. The function of the route determination program is to select a route in the network in accordance with a number of conditions and based on the network topology, as well as to generate a request in the SSA, indicating the specific network elements used and their ports (i.e., the selected input port and the selected output port). Information about the selected ports is then transmitted from the SSE to the EMS (network element management system) of each element selected for the route (the EMS blocks: 1, i ... n are indicated by the number 16 of the link). The TMN of a particular network element searches for an internal connection between the selected input port and the selected output port using information 18 available on the ports and based on specific limitations known by the TMN. Limitations may be as follows: selected ports may or may not be available, connection points in selected ports may or may not be available, some connection points may be prohibited from being used for the type of connection required, etc. Limitations and physical availability of connections can be reflected in the so-called port availability data associated with a specific port, and in the TMN there is the same amount of such data (databases) as the number of ports in an element. After clarification of all issues related to the accessibility of the relevant TMN, a report is generated for the SSM on whether a solution was found for possible connectivity. The interaction between the SSAs and the OMS can involve many steps and therefore takes a considerable amount of time. The route determination process is complex and lengthy; when pauses are formed during the process to submit a request to the EMS, such interruptions in work / interaction take considerable time.

Figure 2 shows a diagram reflecting the interaction between the modified SSE and a variety of SUE in accordance with one embodiment of the proposed invention. The modified SSE contains a connection capabilities manipulator (MS) with a connection capabilities table (TS), which, in general, can consist of connection capabilities tables of all the relevant EMSs for making decisions on connection capabilities at the SSE level. In this case, a dynamic update of the connection capabilities manipulator can be provided according to element restrictions, for example, changes in the status of ports / connection points, as indicated by dashed lines.

Preferably, all the connection points existing in the ports of the network elements (see also FIG. 3) controlled by the SSAs are classified into connection groups. Each of the groups is characterized by certain properties and limitations. Due to this, a huge number of connection points of all network elements are divided into a relatively small number of groups, each of which has a known behavior. SSA 20 (see figure 2) contains the determinant 22 of the route, the modified data 24 topology, which additionally contains information about specific groups of connections that exist (or assigned) in each port of the network elements.

The modified SSA further comprises a new connection capability manipulator (MS) block 26, which comprises a connection capability table (TS) 28. One preferred example of a connectivity table is shown below in FIG. 4. The connection capabilities table 28 actually contains the so-called general connection capabilities rules, which formulate (at the SSA level) whether the ports selected by the route determiner can be interconnected and introduce compatibility / incompatibility conditions between the connection groups of the input and output ports. Because connection point connection groups are formed throughout the network, these compatibility conditions apply to any network element that has ports containing any of these groups.

The TS table (28) of the connection possibilities of the MS block (26) after receiving information about the connection groups existing in the selected ports of the element specified for the route, allows you to generate responses regarding possible connections. This information can be transmitted to the appropriate TMN 32 to select a real internal connection and its activation. However, to minimize the likelihood that the required connection will be occupied, the CCA can access the level of the EMS only after exchanging information with the additional block 30 of the connection capabilities manipulator 26. This block is called a hashed table (XT), in which only busy connections of each network element are recorded; It is constantly updated by the TMS 1, ... m. When a possible connection is allowed by the TS and XT is verified, the internal connection can actually be indicated and transferred for activation to the corresponding TMN 32.

Figure 3 shows a network element 40 having a plurality of input ports 42 (1, ... K) and a plurality of output ports 44 (1, ... F). Each of the ports contains connection points, represented as circles and indicated by the number 46. All connection points existing in network elements controlled by the SSA in accordance with the present invention are schematically divided into a number of groups of 1, 2 ... n connections. Each of the groups is characterized by its specific limitations and the behavior (properties, features) of the connection points.

For example, the connection points of a particular group located in the input ports can only be connected to the connection points of the same group located in the output ports. In one case, the input port connection points can be designed to enter the network element, such as cross-connection, virtual containers carrying data in accordance with the SDH / SONET (SDH - Synchronous Data Hierarchy European standard for the use of optical cables as physical data transmission medium for high-speed transmission networks over long distances, SONET - Synchronous Optical Network standard that defines the speeds, signals and interfaces for a synchronous optical network providing transmission speed and data of more than one gigabit per second). In this case, the connection point may be called the point of VK (VC) (virtual channel). In SDH switching equipment, VC points are typically designed to input / output data streams in accordance with the VC-4 standard.

Each port contains connection points 46 belonging to one or several groups 48. For example, input port 1 (indicated by 50) contains connection points 46 belonging to three connection groups 48, namely connection groups 1, 2, and 5. Each of the connection points within the same group has its own serial number or other designations.

Figure 4 presents an example of a preferred embodiment of a table (TS) 52 of connectivity, which contains n columns 54 and n rows 56, where each row is allocated to a specific group of connections, or input ports, or simply "groups of input connections", and each of the columns assigned to a specific "output connection group." The symbols at the intersections of a particular column and a specific row have the meaning that the inner connection between a particular input connection group and a specific output connection group is impossible or possible if there are or are not certain conditions.

Figure 5 presents a fragment of the database of busy connections or the so-called hashed subtable 58 for a particular network element. The table does not have any standardized volume and contains only chains 60, which contain information about currently occupied connections in network elements. The table is used as follows: after determining possible connections, say, between the input connection group 1 and the output connection group 2, the SSA checks the hashed subtable of the element of interest to indicate specific connection points for the SEE. Since the connection points 4 and 1 of the input group 1 of the connections are already taken, they will not be indicated at the disposal. In addition, the connection point 5 of the output group of 2 compounds cannot be indicated. In addition, it is assumed that other connection points exist in the selected groups of corresponding input and output ports of the required element, and they will be approved by the TMN. However, the table will be useless if additional join points in the corresponding groups are not provided in addition to those that are already occupied. In this case, a negative answer will be received from the control system, in this special case a sequential repeatedly repeated interaction will occur between the control system and the control system. To eliminate this situation, the modified topology data may, if necessary, contain information about the total number of input contact points (output contact points) of each group of the input (output) port. This information can be compared with information about busy connections in a hashed table to obtain accurate information regarding the fact that at least one available combination exists, and based on this comparison, it is possible to obtain a well-established order of connection possibilities for the TMN, if the answer is positive, or prohibit recourse to the TMN if the answer is no.

Although the present invention has been described using a number of specific examples, it should be understood that other embodiments of a network management system may be proposed that can provide connectivity solutions for the network elements it manages at the SSA level by creating and using general connectivity rules, and modified ways to use such SSAs, although all such embodiments / methods should be considered part of the concept of the present invention.

Claims (10)

1. A method of finding solutions for connectivity for network elements included in a route selected in a network managed by a network management system SSU, in which each network element contains input ports and output ports, each of which allows you to use many connection points containing formation in the SSD of the BS database of the connection capabilities containing data on possible internal connections between the connection points of any input port and the connection points of any output port in any network in this case, the BS controlled by this SSU, in this case, the BS is formed by classifying the connection points of the input and output ports of all network elements into a set of connection groups symbolically designated 1, 2, 3 ... n, with each of the groups characterized by similar properties and / or restrictions, the assignment to each input port and each output port of a particular network element of one or more of the specified connection groups, the formation of general principles on connection capabilities, indicating the possibility of unity between any arbitrary group of connections from groups 1, 2, 3 ... n belonging to the input port of the network element, and any arbitrary group of connections from groups 1, 2, 3 ... n belonging to the output port of the network element, the method additionally contains a search for the required connections between the input port and the output port of a particular network element by using the database of the connection capabilities of the BS to determine at the SSE level whether the desired connection can be made between at least one of the connection groups the input port and at least one group of output port connection groups. 2. The method according to claim 1, in which the step of creating a database of connectivity BS includes organizing a table of connectivity (TS) so that the rows of the table represent groups 1, 2, ... n connections of input ports, the columns of the table represent groups 1 , 2, ... n connections of the output ports, and each intersection cell between a particular row and a specific column contains information about the possibility of forming an internal connection between the connection point belonging to the specified specific group of input ports and the soy point The port that belongs to the specified specific group of output ports. 3. The method according to claim 1, wherein the step of searching for the required connections comprises the steps of: accessing the SSD by indicating a specific network element with its input port and its output port required for the selected route, to obtain a decision on the possible connectivity for the specified network element; determining which of the connection groups from the indicated groups 1, 2, ... n is present in the specified input port, and which is in the specified output port; the application of the principles of connectivity by using the specified database of connectivity BS capabilities in the SSA to determine whether the desired connection can be made between at least one group of connection groups of the input port and at least one group of connection groups of the output port; in case of confirmation of such a possibility, consideration of the decision on the determined connectivity; access from the SSA to the control system of the network element of the EMS for a specific network element to activate a specific internal connection in the specified network element; in the case of a negative decision result, transmission to the SSA a message stating that the decision on the possibility of connection is not defined for the indicated specified input port and specified output port of the specified network element. 4. The method according to claim 1, further comprising the step of indicating at the SSU level an internal connection between the contact point from the input connection group and the contact point from the output connection group, in which the specified input connection group and the specified output connection group are selected at the SSU level, as a solution connectivity for the specified specific network element. 5. The method according to claim 1, additionally containing a step of checking information about busy connections by first providing a database of busy connections to the SSA and then accessing it, moreover, the indicated connections indicate internal connections of network elements currently occupied. 6. The method according to claim 5, containing the use of a BS that reflects the indicated general rules of connectivity and also contains a preliminary presentation and subsequent access to a database designed to register the set of existing connection points in each connection group of each port of a particular element; following the comparison of information about existing connection points in the selected input and output connection groups with information about busy connections. 7. An SSA network management system comprising an MS of a connectivity manipulator that provides the ability to determine at the SSU level a connectivity solution for a particular network element that should be included in a route selected over a network controlled by the SSU, in which the connectivity manipulator contains a base BS data of the connection capabilities, which contains data on possible internal connections of any of the network elements, while the SSU network management system additionally contains It contains topological data related to the elements of the specified network and their ports, in which each input port and each output port of any network element, respectively, are assigned one or more groups of 1, 2, ... n connections for connection points so that each group of compounds is characterized by similar properties and / or limitations, and in which the BS contains general principles of connectivity indicating the possibility of formation of a connection between any arbitrary group of compounds from groups 1, 2, 3 ... n belonging to the input one port of the network element, and any arbitrary group of connections from groups 1, 2, 3 ... n belonging to the output port of the network element. 8. The system according to claim 7, in which the database of connectivity database BS is constructed in the form of a table so that the table rows represent groups 1, 2, ... n connections belonging to the input ports, the table columns represent groups 1, 2, .. .n connections belonging to the output ports, and each intersection cell between a particular row and a specific column contains information related to the possibility of creating an internal connection between at least one connection point from the group of connections belonging to the input port of the network element the one and the at least one connection point from the group of compounds belonging to the output port of said network element. 9. The system according to claim 7, in which the MS further comprises a database of busy connections in the form of information chains, each of which denotes the internal connections that are currently occupied, in a particular network element. 10. The system according to claim 9, in which the topological data contains a database for registering the set of existing connection points in each connection group for each port of each specific element, and this TS allows you to compare information about existing connection points in the selected input and output connection groups selected ports of the selected item with information obtained from the database of busy connections.

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