KR100772524B1 - Label switch route selection system and method based on network management system - Google Patents

Abstract

The present invention relates to a device and method for selecting a label exchange path in a network management system. The present invention analyzes and quantifies link performance information, fault occurrence and fault history, and converts them into standardized values. A link weight management unit and the management to determine a link weighting value using a value obtained by subtracting a reference value calculated through a predetermined weighting algorithm from a second constraint corresponding to qualitative information associated with The route list is configured through a technique of performing a predetermined background task by designating a source and a destination among all nodes in the network, and corresponding to objective information related to the route selection required by the management network policy among the routes in the route list. Select a path that satisfies the first constraint, and if the selected path If the material needs to be composed of a selected LSP path for selecting a path that minimizes the cost of using the link weights provides the best path selected in accordance with the network management policy.

Network Management System, Links, Constraints, Label Exchange

Description

Label switch route selection system and method based on network management system

1 is a view showing the components of the label exchange path selection apparatus according to a preferred embodiment of the present invention.

FIG. 2 is a conceptual diagram illustrating constraints required by the management network policy and default values provided by the management network policy according to an exemplary embodiment of the present invention.

3 is a view showing a cost equation for selecting a label exchange path according to an embodiment of the present invention.

4 is a flowchart illustrating a label exchange path selection according to a preferred embodiment of the present invention.

5 is a flowchart illustrating a label exchange path selection reflecting link weighting using default values provided in a management network policy according to an exemplary embodiment of the present invention.

The present invention relates to an apparatus and method for selecting a label exchange path in a network management system. More particularly, the present invention relates to constraints on a network state in a multi-protocol label switch system (MPLS), and prioritizes network policies. As the route is calculated by arbitrating the rank, the reliability and flexibility of the network can be increased, thereby providing a practical label exchange path device and method from the ingress node to the egress node.

The prior art is related to a path search having various constraints such as bandwidth and delay in combination with Dijkstra's algorithm, which is a method of simply selecting a path as the shortest path. OSPF-TE (Open Shortest Path First-Traffic Engineering) has been used as a routing protocol (Routing Protocol) routing selection algorithm, and it exchanges a lot of information in order to obtain more accurate neighbor network status information. One of these techniques is route selection based on quality of service (QoS), which calculates and selects routes based on link cost and delay. Such a technique is difficult to deal with when there is a conflict between constraints, and the network load is increased as the flooding information between devices increases.

Another conventional technique is a technique for supporting a Service Level Agreement (SLA) for a Label Switched Path (LSP) from an ingress node to an egress node. The LSP is configured in a centralized network management system, and the link state And techniques for monitoring usage and remediating established routes. Although the centralized network management system attempts to reduce the load of sending and receiving a lot of information to be transmitted to each node for the efficiency of path calculation, there is still a problem that the conflicts between the above-mentioned constraints are not properly coordinated.

The technical problem to be achieved by the present invention is to reflect the constraints well in the network state in the multi-protocol label exchange system (MPLS), and to calculate the path by arbitrating the priority between network policies, thereby increasing the reliability and flexibility of the network in a practical ingress node. An apparatus and method for label exchange route to an egress node is provided.

Another object of the present invention is to provide a computer readable recording medium having recorded thereon a program for performing a label exchange path method on a computer.

In one embodiment of the label exchange path selection device according to the present invention for solving the above technical problem, the state analysis unit, management network policy to analyze and quantify the performance information, failure occurrence and failure history of the link to a standardized value The link weighting value is determined using a reference value calculated by a predetermined weighting algorithm for the second constraint corresponding to the qualitative information associated with the performance analysis of the required path, using a value obtained by subtracting the standard value from the standardized value of the state analyzer. A route weighting management unit and a route list are configured through a technique of performing a predetermined background task by designating a source and a destination among all nodes in the management network, and selecting a route required by the management network policy among the routes existing in the route list. Select a path that satisfies the first constraint corresponding to the objective information associated with If the path is present more than one is characterized by comprising a selecting section for selecting the LSP path, the path that minimizes the cost of using the link weights.

The performance information of the link provided to the state analyzer may be periodic performance information or a performance limit value.

The state analysis unit may include a link state analysis unit for quantifying performance information and a failure history by determining link usage, and an LSP state analysis unit for quantifying by measuring delay information of the LSP.

The first constraint required by the management network policy is characterized in that the bandwidth, delay, link AFFINITY, explicit path, node exclusion / inclusion.

The second constraint for calculating a reference value in the management network policy of the link weight management unit is characterized in that the connection robustness, load balancing of the connection, stability of the connection.

The link weight management unit sets a priority according to the management network policy among the robustness of the connection, the load balancing of the connection, and the stability of the connection, and then quantifies the value in the ratio of 3: 2: 1 in order of high priority to low priority. Compared with the to determine the link weight value.

 When there are a plurality of selected paths, the LSP path selection unit selects a path that minimizes cost by using a link weighting value reflecting the priority.

In an embodiment of the method for selecting a label exchange path according to the present invention for solving the technical problem, a state analysis step of analyzing and numerically converting the performance information of the link, the occurrence of the fault and the history of the link to a standardized value, the performance of the link Analyze and quantify information, failure occurrence, and history of failures and convert them into standardized values, and apply a predetermined weighted algorithm to the second constraint corresponding to qualitative information associated with performance analysis of the path required by the management network policy. Determining the link weighting value using the reference value calculated through the standard value added or subtracted from the standard value, and designating the route weight as a source and a destination among all nodes in the management network to perform a predetermined background task And objective definitions related to route selection required by the management network policy among routes existing in the route list. Selecting a path that satisfies the first constraint corresponding to the beam, and if there are several selected paths, selecting a path that minimizes the cost by using the link weight value. do.

In addition, the network management system according to the present invention includes a computer-readable recording medium having recorded thereon a program for executing a label exchange path selection method on a computer.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

1 is a view showing the components of the label exchange path selection apparatus according to a preferred embodiment of the present invention. Referring to FIG. 1, the LSP path selection unit 100, the link weight management unit 101, the link state analysis unit 102, and the LSP state analysis unit (located on the centralized network management system 104) 103).

The present invention is located in a centralized network management system, and is easy to analyze the network state and reflect the actual state of the network in the path selection. The distribution of routing blocks in each node has the advantage of balancing the load, as opposed to centralized. However, as high-quality services that need to support QoS such as multimedia application services such as voice and video are required, specific data for reflecting the network situation increases, and the amount of data between all routing blocks increases rapidly, thereby putting a load on the network. In addition, a complex block for analyzing specific data must exist at every node, resulting in a high price increase. In order to compensate for this disadvantage, the present invention is located in a centralized network management system.

The state analyzer 102 and 103 analyzes, quantifies, and converts the performance information of the link, the occurrence of the failure, and the failure history into standardized values.

The link weight management unit 101 determines a link weighting value by using a value obtained by subtracting the reference value provided in the management network policy from the standard value of the state analyzer.

The LSP route selector 100 designates a source and a destination among all nodes in the management network to perform a background task of constructing a route list using an improved heuristic depth first search (DFS) technique, and the routes existing in the route list. Select a path that satisfies the constraints required by the management network policy.

FIG. 2 is a conceptual diagram illustrating constraints required by a management network policy and default values provided by the management network policy according to an exemplary embodiment of the present invention. Referring to FIG. 2, constraints are defined as primary and secondary constraints. Dispose separately.

Basic constraints define basic information such as bandwidth, quality (delay), link affinity, explicit path, and node exclusion / included when requesting LSP configuration. Multiple primary constraints may be given in one request, and all of the given primary constraints must be satisfied.

Practical constraints define practical information such as link type, failure history, performance analysis, and usage for load balancing. Secondary constraints have a higher priority, so the higher-priority constraints control the link weight change more than the lower-priority constraints.

3 is a view showing a cost equation for selecting a label exchange path according to an embodiment of the present invention. The cost calculation will be described later in the description of the flowchart of FIG. 4.

4 is a flowchart illustrating a label exchange path selection according to a preferred embodiment of the present invention, and FIG. 5 is a label exchange path selection reflecting link weighting using default values provided in a management network policy according to a preferred embodiment of the present invention. It is a flow chart. The flowcharts of FIGS. 4 and 5 together with the functionality of each component of FIG. 1 will be described.

The LSP path selector 100 performs a background job and a real time job. The background task of LSP route calculation and selection is to design a full mesh route list with an improved heuristic DFS (DFS) technique by specifying a source (S) and a destination (D) among all nodes in the management network. (401). For full mesh routes of any S and D, _n C ₂ entries are generated when the total number of nodes is n, and a plurality of route lists may exist in each entry of a full S and D full mesh route. have. The real-time operation of the LSP path calculation and selection unit is performed when a path is selected to S and D (400), and may include one or more primary constraints required at this time. It is determined whether a route satisfying the given first constraint exists in the route list composed of background tasks (402).

If there are multiple such paths, the paths are selected by the calculated value 200, i.e. cost 201, reflecting the preset secondary constraint priority. If there are multiple paths with the same value, the path with the least hop count among them is selected.

In the present invention, the link weight is divided into 10 levels of grades, 1 to 10, and the smaller the link weight value has a higher priority in link selection. Link weighting is initially given a default value, and it is added or decreased to reflect the network situation at the request of the operator. The operator assigns priorities such as 1) vigorous connection 2) load balancing of the connection 3) stability of the connection (500).

For example, if the robustness of the connection is the highest priority, give the link the lowest value for the link with 1 + 1 line switching and the default value for the link type to give the link priority. Do it. In addition, if the section to which the switching of the layer 1 is applied, the least value is given to give an advantage in link selection.

If the load balancing of the connection is the highest priority, the link usage is analyzed and the link weighting is increased accordingly to give an advantage in link selection.

If the stability of the connection is the highest priority, performance information and failure history are analyzed to give the link selection advantage by giving the smallest value to the link weight of the link that has a low performance limit or the frequency of failure history. When the priorities of the above three items are determined, the link weight is adjusted and reflected in the link weighting at a ratio of 3: 2: 1 in the order of high priority to low priority (503).

This dynamically adjusted link weight acts as an important variable in the calculation of FIG. 3, and the present invention uses this to select a path. The link weight management unit 101 receives the events of the link state analysis unit and the LSP state analysis unit 501 and reflects them in the above-mentioned ranking. The link overload management unit is performed as a background task after the operator sets the secondary constraint priority, and the value of the link overload management unit is reflected in the path selection during the real-time operation of the LSP path selection unit 100 (403).

The link state analysis unit 102 analyzes the periodic performance information, analyzes the performance threshold, analyzes the occurrence of the failure and the failure history, converts it into a standardized value, and provides the link weighting unit in the link weight management unit. When the state changes, an event is triggered in the link weight management unit. The link state analysis unit uses the link usage to reflect the load balance, and reflects the failure history and performance information to achieve the stability of the connection.

The LSP status analyzer 103 analyzes the periodic performance information, analyzes the performance threshold, analyzes the occurrence of the failure and the failure history, converts it into a standardized value, and provides the link weighting unit in the link weight management unit. And when the state changes, it generates an event in the link weight management unit. The LSP state analysis unit obtains delay information of an arbitrary LSP and reflects it when setting up the next LSP, or determines whether the selected LSP conforms to a policy and resets it if it does not match.

We present practical constraints that fit the characteristics of the network and a route selection method with priority on various constraints. In order to establish a Label Switched Path (LSP) of a multi-protocol label switch (MPLS) label in the network, bandwidth, link affinity, which are basic constraints for QoS, In addition to delays, explicit routes, and node exclusive / inclusive, practical constraints such as link type, fault history, and performance analysis Performance analysis and utilization for load balancing are extracted and prioritized, dynamically routed according to operator choice and network management mechanisms.

Among the constraints, the link weight values are analyzed in order of the higher priority condition, and the network weight is added and subtracted according to the actual situation. The path is calculated using the dynamic link weight. The present invention computes the path with an improved depth first search (heuristic DFS). The path selection method of the present invention has priority for each constraint compared to the existing multiple constraint selection, so that different paths can be selected according to the path operation policy, thereby providing flexibility in path management and linking according to network conditions. Since the weights are dynamically adjusted, there is an advantage to establishing a practical path.

The invention can also be embodied as computer readable code on a computer readable recording medium. The computer-readable recording medium includes all kinds of recording devices in which data that can be read by a computer system is stored. Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage, and the like, and may also be implemented in the form of a carrier wave (for example, transmission over the Internet). Include. The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

As described above, optimal embodiments have been disclosed in the drawings and the specification. Although specific terms have been used herein, they are used only for the purpose of describing the present invention and are not intended to limit the scope of the present invention as defined in the claims or the claims. Therefore, those skilled in the art will understand that various modifications and equivalent other embodiments are possible from this. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

In the present invention, the label exchange route calculation and route selection are formulated into network constraints as constraints and reflected in the route selection. You can make choices so you can make practical path choices. This has the following features.

First, network constraints can be reflected in the label exchange path by dividing the constraints into primary and secondary.

Second, since the link weight is dynamically added and analyzed by analyzing the network actual situation, it is possible to select a label exchange path that is more practical and relatively optimized for the network situation.

Third, since the label exchange path is selected by giving priority to the network management policy of the operator, it is possible to provide the operator with the convenience of automated label exchange path selection by preventing conflicts between the policies.

Fourth, since the practical delay information is analyzed and extracted by performing LSP state analysis as well as link state analysis, it is possible to calculate a path based on relatively accurate delay information.

Claims (14)

A state analysis unit for analyzing, quantifying and converting performance information of a link, occurrence of a failure, and a history of failure to a standardized value; A link weight management unit for determining a link weighting value based on a standard value calculated through a predetermined weighting algorithm and a second constraint associated with performance analysis of a path required by a management network policy; And A route list is configured through a technique of performing a predetermined background task by designating a source and a destination among all nodes in the management network, and basic information related to route selection required by the management network policy among the paths existing in the route list. A label switched path (LSP) path selector for selecting a path that satisfies a first order constraint and selecting a path that minimizes a cost by using the link weighting value if there are several selected paths; Label exchange route selection device comprising a. The method of claim 1, The performance information of the link provided to the state analysis unit is a label exchange path selection device, characterized in that the periodic performance information or performance limit. The method of claim 1, The state analysis unit includes a link state analysis unit for quantifying performance information and a failure history by determining link usage, and a LSP (Label Switched Path) state analysis unit for measuring and quantifying delay information of a label switched path (LSP). Label exchange route selection device. The method of claim 1, And a primary constraint required by the management network policy is bandwidth, delay, link AFFINITY, explicit path, node exclusion / inclusion. The method of claim 1, And a second constraint for calculating a reference value in the management network policy of the link weight management unit is connection robustness, connection load balancing, and connection stability. The method of claim 5, The link weight management unit determines a link weighting value by comparing the reference value calculated according to the priority by setting the priority according to the management network policy among the robustness of the connection, load balancing of the connection, and stability of the connection. Label exchange route selection device. The method of claim 6,  The LSP path selector selects a path that minimizes cost by using a link weight value reflecting the priority when there are a plurality of paths satisfying the first constraint. Label exchange route selection device. The method of claim 7, wherein The Label Switched Path (LSP) path selection unit selects a path having a minimum cost of the path calculated based on the sum of the risks of the link through the path reflecting the weight of the link and the hop count. Device. The method of claim 7, wherein The label switched path (LSP) path selecting unit selects a path having a minimum hop count when there are a plurality of paths that minimize the cost. A state analysis step of analyzing, quantifying and converting performance information of a link, a failure occurrence, and a history of failures into standardized values; Analyzing, quantifying, and converting performance information, failure occurrence, and failure history of the link into standardized values; Determining a link weighting value based on the standardized value and the standardized value of the second constraint associated with the performance analysis of the path required by the management network policy through a predetermined weighting algorithm; And A route list is configured through a technique of performing a predetermined background task by designating a source and a destination among all nodes in the management network, and basic information related to route selection required by the management network policy among the paths existing in the route list. Selecting a path that satisfies a first order constraint and, if there are several selected paths, selecting a path that minimizes cost by using the link weighting value; How to select a route. The method of claim 10, The state analysis step includes determining the usage of the link to quantify the performance information and failure history, and measuring and quantifying the delay information of the label switched path (LSP). The method of claim 10, The primary constraints required by the management network policy are bandwidth, delay, link AFFINITY, explicit path, node exclusion / inclusion, and secondary constraints are connection robustness, connection load balancing, and connection stability. Label exchange route selection method comprising a. The method of claim 12, And a link weighting value is determined by comparing the reference value calculated according to the priority according to the management network policy among the robustness of the connection, load balancing of the connection, and stability of the connection. A computer-readable recording medium having recorded thereon a program for performing the method of selecting a label exchange route according to any one of claims 10 to 13.

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