JP4335889B2 - Route estimation method, apparatus and program - Google Patents

Description

  The present invention relates to a path estimation method, apparatus, and program, and in particular, IP (Internet Protocol) routing such as OSPF (Open Shortest Path First), RSVP-TE (Resource Reservation Signaling Protocol for Traffic Engineering) and LDP (Label Distribution). In an MPLS (Multi Protocol Label Switching) network that operates Protocol), LSP (Label Switched Path) with various settings of LDP and RSVP-TE is set, and RSVP-TE LSP has FRR (Fast Reroute) and A path estimation method and apparatus for estimating how a path of IP traffic or MPLS traffic changes when a failure occurs or recovers from a failure in an environment where a protection method such as Backup LSP is set Regarding the program.

  In recent years, MPLS has attracted attention as a technology for realizing traffic engineering and IP-VPN. In MPLS, the route is determined by the distribution of the label. The methods include the method of following the shortest route of IGP (Interior Gateway Protocol) like LDP and RSVP-TE (see Non-Patent Document 1, for example). There is a method of explicitly specifying a route and reserving a network bandwidth.

  In RSVP-TE, Explicit Route can be specified in a signaling message. The specification method includes Strict specification that specifies all passing nodes, and the Loose specification that follows the shortest route of IGP for the route between the specified nodes. There is. In addition, it is possible to secure a bandwidth by designating a required bandwidth for each LSP. Therefore, LSP cannot be set when there is no available bandwidth in the link on the route determined above.

  In RSVP-TE, it is possible to set a protection method that bypasses the LSP when a failure occurs. There are two protection methods: Local Repair and Global Repair. Local Repair is a method of partially and rapidly bypassing a failure location of an LSP, and is also called FRR (see Non-Patent Document 2, for example). As shown in FIG. 14, FRR includes a one-to-one backup in which a node automatically calculates and configures a Detour LSP using the CSPF algorithm to protect all nodes and links of one LSP, There is Facility Backup that protects link nodes and can bypass multiple tunnels simultaneously. The bypass path of Facility Backup is called Bypass LSP, and there are a method in which the node automatically calculates by the CSPF algorithm and a method to specify the Explicit Route as in the LSP. In the Detour LSP and Bypass LSP, the node on the LSP that is the starting point of the detour is called PLR (Point of Local Repair), and the node on the LSP that is the end point of the detour is called MP (Merge Point). When recovering from a failure, it often returns automatically to the original route. Global Repair is a method of switching to a new LSP between Ingress-Egress nodes of an LSP. A spare LSP (Backup LSP) is set in advance, and when a failure occurs is notified to the Ingress node, it is switched to the Backup LSP. There is a way. In this case, whether or not to automatically switch back to the original LSP at the time of failure recovery can be determined by setting. In addition, when the failure location is in the loose designated section, if a route is found by performing recalculation of the route, the Ingress node switches to a new route and Global Repair is executed. However, even if a route is found by recalculation of the route, it cannot be bypassed if there is no available bandwidth for the requested bandwidth.

  In this way, in RSVP-TE, the path change method at the time of failure occurrence or failure recovery varies greatly depending on the setting method of LSP and protection method, and the traffic flowing through the RSVP-TE LSP also changes to the LSP path change. Follow and change. On the other hand, LSP LSP, traffic, and IP traffic are not routed or reserved for bandwidth, so even if a failure occurs, the shortest route is calculated using resources that normally exist in the network, and the route must be discovered. Communication is performed along that route.

In this way, in a network where IP and MPLS are mixed, in order to know the path change at the time of failure occurrence or recovery, complicated calculation is required, but a simulator that automatically calculates and estimates this is a conventional technology. Exists (see, for example, Non-Patent Document 3).
RFC3209 RSVP-TE Extensions to RSVP for LSP Tunnels RFC4090 Fast Reroute Extensions to RSVP-TE for LSP Tunnels "IP / MPLS View", WANDL, [online], posting date unknown, [March 7, 2006 search] Internet <URL: http://www.wandl.com/html/mplsview/MPLSview_new.cfm>

  However, the route of the actual IP / MPLS network is not a method of estimating the route taking into account the combination of settings such as the explicit route and reserved bandwidth of RSVP-TE, FRR setting and Backup LSP setting, and the reserved bandwidth of other LSP. It was not accurate to simulate the fluctuations. Also, when designing an LSP or protection to build a network with high protection capability at the time of failure, it was very difficult to manually calculate and estimate the path change at the time of failure.

  The present invention has been made in view of the above points, and provides a route estimation method, apparatus, and program capable of correctly estimating a route when a failure occurs in a network in which MPLS and IP are mixed. Objective.

  FIG. 1 is a diagram for explaining the principle of the present invention.

In the present invention (Claim 1), an IP routing including OSPF, and an MPLS network in which RSVP-TE and LDP operate, an LSP and an alternative route including FRR and Backup LSP are set in the LSP. A route estimation method at the time of failure occurrence that estimates the LSP and traffic route change when a failure occurs in a certain link or node under the situation where traffic communication is performed,
The information acquisition means communicates topology information representing the connection relationship of each node of the network, individual setting information of LSP groups set in the network, LSP information representing the use route and state, and communication. Information acquisition step (step 1) of acquiring traffic occurrence information, FEC information associating the LSP and MPLS traffic, and failure occurrence location information indicating location information of the failure occurrence location, and storing them in the information storage means;
The RSVP-TE-LSP route calculation means refers to the information storage means, obtains the RSVP-TE LSP information out of the LSP information, calculates the change in the route due to the occurrence of the failure, and uses the new LSP route and status. RSVP-TE-LSP path calculation step (step 2) for storing the information in the calculated LSP storage means;
The LSP path calculation means refers to the information storage means, acquires LSP information other than RSVP-TE among the LSP information, calculates the path change due to the occurrence of a failure, and calculates the new used path and status of the LSP LSP route calculation step (step 3) to be stored in the LSP storage means;
The MPLS traffic route calculation means acquires MPLS traffic information from the traffic information stored in the information storage means, refers to the FEC information stored in the information storage means, and is associated with MPLS traffic. MPLS traffic route calculation step (step 4) for acquiring the new usage route from the calculated LSP storage means, and storing the new usage route in the calculated traffic storage means as the new usage route of the MPLS traffic;
IP traffic route calculation means obtains IP traffic information from the traffic information stored in the information storage means, calculates the change in the route due to the occurrence of a failure, and calculates the new usage route of IP traffic. IP traffic route calculation step (step 5) to be stored in
The route output means performs a route output step (step 6) for outputting the LSP stored in the calculated LSP storage means and the calculated traffic storage means and the route for each traffic.

Further, the present invention (Claim 2) provides an RSVP-TE-LSP route calculation step (Step 2).
The LSP classification means refers to the LSP information of the RSVP-TE in the information storage means and classifies the LSP group that is affected by the occurrence of the failure and the LSP group that is not affected by the occurrence of the failure. An LSP classification step (step 21) to be stored in the classification storage means;
An unaffected LSP calculation means acquires an LSP group that is not affected by the occurrence of a failure from the LSP classification storage means, and stores the LSP group in the calculated LSP storage means together with LSP information (step 22). When,
The affected LSP calculation means acquires one LSP that has not been calculated yet from the LSP classification storage means by referring to the calculated LSP storage means from among the LSP groups affected by the occurrence of the failure. An LSP calculation step (step 23) having an effect of referring to the LSP information and the failure occurrence position information, calculating a new use route and state, and storing the LSP together with the new LSP information in the calculated LSP storage means;
The affected LSP calculation step (step 23) is repeated until an LSP that has not been calculated cannot be acquired.

In the present invention (Claim 3), when performing a route estimation when a failure occurs in a certain place,
In the LSP classification step (step 21) of the RSVP-TE-LSP route calculation step,
The LSP groups that are affected by the occurrence of a failure are further classified into an LSP group in which the usage route in the LSP information passes through the failure occurrence location, and an LSP group that may change from a failure state to a success state. Store in LSP classification storage means for each classification together with LSP information,
Influenced by RSVP-TE-LSP path calculation step In the LSP calculation step (step 23),
The LSP group in which the usage route in the LSP information passes through the failure occurrence location is calculated first, and the LSP group that may change from the failed state to the successful state is calculated later.

In the present invention (Claim 4), an IP routing including OSPF, and an MPLS network in which RSVP-TE and LDP operate, an LSP and an alternative route including FRR and Backup LSP are set in the LSP. It is a route estimation method at the time of failure recovery that estimates LSP and traffic route change when a link or node failure is recovered under the situation where traffic communication is performed,
The information acquisition means communicates topology information representing the connection relationship of each node of the network, individual setting information of LSP groups set in the network, LSP information representing the use route and state, and communication. Information acquisition step (step 1) for acquiring traffic recovery information, FEC information for associating the LSP and MPLS traffic, and failure recovery location information indicating location information of the failure recovery location, and storing the information in the information storage means;
The RSVP-TE-LSP route calculation means refers to the information storage means, obtains the RSVP-TE LSP information out of the LSP information, calculates the change in the route due to the failure recovery, and uses the new LSP route and status RSVP-TE-LSP path calculation step (step 2) for storing the information in the calculated LSP storage means;
The LSP route calculation means obtains LSP information other than RSVP-TE from the LSP information stored in the information storage means, calculates the change of the route due to failure recovery, and calculates the new usage route and status of the LSP LSP route calculation step (step 3) to be stored in the stored LSP storage means;
The MPLS traffic route calculation means acquires MPLS traffic information from the traffic information stored in the information storage means, refers to the FEC information stored in the information storage means, and is associated with MPLS traffic. MPLS traffic route calculation step (step 4) for acquiring the new usage route from the calculated LSP storage means, and storing the new usage route in the calculated traffic storage means as the new usage route of the MPLS traffic;
The IP traffic route calculation means obtains IP traffic information from the traffic information stored in the information storage means, calculates the change in the route due to failure recovery, and calculates the new usage route of the IP traffic. IP traffic route calculation step (step 5) stored in the means;
The route output means performs a route output step (step 6) for outputting the LSP stored in the calculated LSP storage means and the calculated traffic storage means and the route for each traffic.

Further, the present invention (Claim 5) provides an RSVP-TE-LSP route calculation step (Step 2).
The LSP classification means refers to the RSVP-TE LSP information stored in the information storage means, classifies the LSP group that is affected by failure recovery and the LSP group that is not affected by failure recovery, along with the LSP information. An LSP classification step (step 21) for storing in the LSP classification storage means for each classification;
An unaffected LSP calculation means acquires an LSP group that is not affected by failure recovery from the LSP classification storage means, and stores the LSP group in the calculated LSP storage means together with LSP information (step 22). When,
The affected LSP calculation means obtains one LSP that has not been calculated yet by referring to the calculated LSP storage means from the LSP group affected by the failure recovery of the LSP classification storage means, and the LSP of the LSP An LSP calculation step (step 23) having an influence that refers to the information and the failure recovery position information, calculates a new usage route and state, and stores the LSP in the calculated LSP storage means together with the new LSP information;
The affected LSP calculation step (step 23) is repeated until an LSP that has not been calculated cannot be acquired.

In the present invention (Claim 6), when performing route estimation when a failure is recovered at a certain point,
In the LSP classification step (step 21) of the RSVP-TE-LSP route calculation step,
The LSP group affected by the failure recovery is further classified into an LSP group in which the use path in the LSP information changes due to the failure recovery and an LSP group that may change from the failure state to the success state, and the LSP group Store in the LSP classification storage means for each classification along with the information,
Influenced by RSVP-TE-LSP path calculation step In the LSP calculation step (step 23),
The LSP group whose usage path in the LSP information changes due to failure recovery is calculated first, and the LSP group that may change from the failed state to the successful state is calculated later.

  FIG. 2 is a principle configuration diagram of the present invention.

In the present invention (Claim 7), an IP routing including OSPF, and an MPLS network in which RSVP-TE and LDP operate, an LSP and an alternative route including FRR and Backup LSP are set in the LSP, and the IP and MPLS A route estimation device at the time of failure occurrence that estimates the LSP and traffic route change when a failure occurs in a certain link or node under the situation where traffic communication is performed,
Topology information representing the connection relationship of each node of the network, LSP information representing individual setting information, usage route and state of LSP groups set in the network, traffic information on which communication is performed, and FEC information that associates the LSP and MPLS traffic, and failure occurrence position information that represents the location information of the failure occurrence location, information acquisition means 110 that stores in the information storage means 170,
Referring to the information storage unit 170, the LSP information of the RSVP-TE is acquired from the LSP information, the change of the route due to the occurrence of the failure is calculated, and the new use route and state of the LSP are stored in the calculated LSP storage unit 180 RSVP-TE-LSP route calculation means 120 to perform,
The LSP information other than RSVP-TE is acquired from the LSP information by referring to the information storage unit 170, the change of the route due to the occurrence of the failure is calculated, and the new usage route and state of the LSP are stored in the calculated LSP storage unit 180 LSP route calculation means 130 for storing;
Among the traffic information stored in the information storage unit 170, the MPLS traffic information is acquired, the FEC information stored in the information storage unit 170 is referred to, and the new use path of the LSP associated with the MPLS traffic is determined. An MPLS traffic route calculation unit 140 that is obtained from the calculated LSP storage unit 180 and stores the new usage route as a new usage route of the MPLS traffic in the calculated traffic storage unit 190;
IP traffic that obtains IP traffic information from the traffic information stored in the information storage unit 170, calculates a change in route due to the occurrence of a failure, and stores a new usage route of the IP traffic in the calculated traffic storage unit 190 Route calculation means 150;
A route output unit 160 that outputs the LSP stored in the calculated LSP storage unit 180 and the calculated traffic storage unit 190 and a route for each traffic.

Further, the present invention (claim 8) is the RSVP-TE-LSP route calculation means 120,
With reference to the RSVP-TE LSP information in the information storage unit 170, the LSP group is classified into the LSP group that is affected by the failure occurrence and the LSP group that is not affected by the failure occurrence, and the LSP classification storage unit 124 for each classification together with the LSP information. LSP classification means 121 stored in
An unaffected LSP calculation unit 122 that acquires an LSP group that is not affected by the occurrence of a failure from the LSP classification storage unit 124 and stores the LSP group together with the LSP information in the calculated LSP storage unit 180;
From the LSP classification storage unit 124, one LSP that has not been calculated yet is acquired by referring to the calculated LSP storage unit 180 among the LSP groups affected by the occurrence of the failure, and the LSP information of the LSP and the occurrence of the failure are obtained. Refers to the location information, calculates a new usage route and state, and stores the LSP in the calculated LSP storage unit 180 together with the new LSP information until the LSP that has not been calculated cannot be acquired. Calculation means 123.

In the present invention (Claim 9), when performing a route estimation when a failure occurs in a certain place,
The LSP classification means 121 of the RSVP-TE-LSP route calculation means 120 is:
The LSP groups that are affected by the occurrence of a failure are further classified into an LSP group in which the usage route in the LSP information passes through the failure occurrence location, and an LSP group that may change from a failure state to a success state. Means for storing in the LSP classification storage means 124 for each classification together with the LSP information;
The LSP calculation means 123 having an influence of the RSVP-TE-LSP route calculation means 120 is:
Means for calculating first the LSP group whose usage route in the LSP information passes through the failure occurrence location and calculating the LSP group that may change from the failed state to the successful state later;

In the present invention (Claim 10), an IP routing including OSPF, and an MPLS network in which RSVP-TE and LDP operate, an LSP and an alternative route including FRR and Backup LSP are set in the LSP. A route estimation device at the time of failure recovery that estimates the LSP and traffic route change when a failure of a certain link or node is recovered in a situation where traffic communication is performed,
Topology information representing the connection relationship of each node of the network, LSP information representing individual setting information, usage route and state of LSP groups set in the network, traffic information on which communication is performed, and FEC information that associates the LSP and MPLS traffic, and failure recovery location information that represents location information of the failure recovery location, information acquisition means 110 that stores in the information storage means 170,
Referring to the information storage unit 170, the LSP information of the RSVP-TE is acquired from the LSP information, the change of the route due to the failure recovery is calculated, and the new use route and state of the LSP are stored in the calculated LSP storage unit 180 RSVP-TE-LSP route calculation means 120 to perform,
Of the LSP information stored in the information storage unit 170, LSP information other than RSVP-TE is acquired, the change of the route due to failure recovery is calculated, and the new usage route and state of the LSP are calculated. The LSP storage unit 180 LSP route calculation means 130 stored in
Among the traffic information stored in the information storage unit 170, the MPLS traffic information is acquired, the FEC information stored in the information storage unit 170 is referred to, and the new use path of the LSP associated with the MPLS traffic is determined. An MPLS traffic route calculation unit 140 that is obtained from the calculated LSP storage unit 180 and stores the new usage route as a new usage route of the MPLS traffic in the calculated traffic storage unit 190;
The IP traffic information stored in the information storage unit 170 is acquired, the IP traffic information is acquired, the route change due to failure recovery is calculated, and the new usage route of the IP traffic is stored in the calculated traffic storage unit 190. Traffic route calculation means 150;
A route output unit 160 that outputs the LSP stored in the calculated LSP storage unit 180 and the calculated traffic storage unit 190 and a route for each traffic.

Further, the present invention (claim 11) is the RSVP-TE-LSP route calculation means 120,
Refer to the RSVP-TE LSP information stored in the information storage means 170 and classify the LSP group affected by the failure recovery and the LSP group not affected by the failure recovery. LSP classification means 121 stored in the classification storage means 124;
An unaffected LSP calculation unit 122 that acquires an LSP group that is not affected by failure recovery from the LSP classification storage unit 124 and stores the LSP group in the calculated LSP storage unit 180 together with LSP information;
From the LSP group affected by the failure recovery of the LSP classification storage unit 124, the calculated LSP storage unit 180 is referred to obtain one LSP that has not yet been calculated, and the LSP information and the failure recovery position of the LSP Refers to information, calculates a new usage route and state, and stores the LSP in the calculated LSP storage unit 180 together with new LSP information until an LSP that has not been calculated cannot be acquired. Calculation means 123.

In the present invention (Claim 12), when performing route estimation when a failure is recovered at a certain point,
The LSP classification means 121 of the RSVP-TE-LSP route calculation means 120 is:
The LSP group affected by the failure recovery is further classified into an LSP group in which the use path in the LSP information changes due to the failure recovery and an LSP group that may change from the failure state to the success state, and the LSP group Means for storing in the LSP classification storage means 124 for each classification together with information,
The LSP calculation means 123 having an influence of the RSVP-TE-LSP route calculation means 120 is:
It includes means for first calculating an LSP group whose usage path in the LSP information changes due to failure recovery, and later calculating an LSP group that may change from a failed state to a successful state.

The present invention (Claim 13) provides a computer with:
A route estimation program for executing each means of the route estimation device according to claim 7.

  As described above, according to the present invention, in a network in which IP traffic and MPLS traffic are mixed, especially in RSVP-TE, when different route settings or reserved bandwidth settings are made for each LSP, or for different protections for each LSP. When the method is set, the way the path changes when a failure occurs or when a failure is restored differs for each LSP. When a failure occurs, it is necessary to automatically and as accurately as possible estimate the change in the route, such as which LSP has lost communication and whether there is a resource where traffic is concentrated due to detours. In addition, when designing the LSP route or designing the protection method, accurate simulation that assumes failure occurrence and recovery is required.

  The present invention solves such a problem as accurately as possible by changing the path at the time of failure occurrence or failure recovery in a network where RSVP-TE LSP of various settings, IP traffic, and MPLS traffic are mixed. It is possible to estimate.

  Further, when LSP and FRR (Fast Re Routing) are set in a network, the present invention makes it possible to accurately simulate a path when a failure occurs and is restored.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[First embodiment]
In the present embodiment, a case will be described in which a traffic path change is estimated when a failure occurs in a certain link or node.

  FIG. 3 shows the configuration of the path estimation apparatus when a failure occurs in the first embodiment of the present invention.

  The route estimation apparatus shown in the figure includes an information acquisition unit 110, an RSVP-TE-LSP route calculation unit 120, an LSP route calculation unit 130, an MPLS traffic route calculation unit 140, an IP traffic route calculation unit 150, a route output unit 160, information It consists of a storage unit 170, a calculated LSP storage unit 180, and a calculated traffic storage unit 190. Topology information, LSP information, traffic information, FEC (Forward Equivalence Class) information, and failure location information are input, and each LSP and traffic Is output.

  The RSVP-TE-LSP route calculation unit 120 includes an LSP classification unit 121, an unaffected LSP calculation unit 122, an affected LSP calculation unit 123, an LSP classification storage unit 124, and a reserved bandwidth storage unit 125.

  The information storage unit 170, the calculated LSP storage unit 180, the calculated traffic storage unit 190, and the reserved bandwidth storage unit 125 are storage means such as a hard disk device.

  4 and 5 are flowcharts of operations in the first embodiment of the present invention.

  Step 101) First, the information acquisition unit 110 acquires topology information representing the connection relationship of each node of the network, and stores it in the information storage unit 170. The topology information includes the metric value and bandwidth of each link in addition to the connection relationship of each node.

  Step 102) Next, the information acquisition unit 110 acquires individual setting information, LSP information indicating the usage route and state of the LSP groups connected to the network, and stores them in the information storage unit 170. Here, in the LSP information, in addition to the RSVP-TE and LDP Primary LSP used as the main route, the Detour LSP, Bypass LSP, and Backup LSP set as the FRR route are handled independently as one RSVP-TE-LSP. The LSP setting information in the LSP information includes ID number, LSP type, Ingress (PLR) node, Egress (MP) node, requested route (only for RSVP-TE-LSP), requested bandwidth (for RSVP-TE-LSP) Only) and protection method (only for RSVP-TE-LSP Primary LSP). Here, in this embodiment, it is assumed that there are two types of LSP types, RSVP-TE and LDP.

  The state in the LSP information covers only RSVP-TE-LSP, and FIG. 6 shows the state of RSVP-TE in the present embodiment.

In the figure,
“Success” state: This represents a state in which there is no failure on the RSVP-TE-LSP and there is no reserved bandwidth over location.
• “Success (FRR)” state: Indicates a state in which only the RSVP-TE Primary LSP is targeted and a failure has already occurred on the LSP, but the failure is avoided by the FRR detour path.
-"Success (FRR, Backup)" state: Only the RSVP-TE Primary LSP is targeted, and a failure has already occurred on the LSP, but the failure is avoided by the FRR detour, and then globalized by the Backup LSP. Indicates that repair is being performed.
-“Failure (Backup)” state: Only the RSVP-TE Primary LSP is targeted, and a failure has already occurred on the LSP, but this indicates a state where Global Repair is being performed by the Backup LSP.
“Failure (No Route)” state: A state in which a route has been disconnected because a failure has already occurred on the LSP or a node or the like does not exist.
-“Failure (No Bandwidth)” state: Indicates that only RSVP-TE-LSP is targeted and there is no failure on the LSP, but there is a reserved bandwidth over location.

  In the present embodiment, only the Success, Failure (No Route), and Failure (No Bandwidth) are present in the LSP state acquired first, and there is no existing failure.

  In the case of RSVP-TE-LSP and the status is “Success”, the usage route in the LSP information is information indicating the nodes through which the LSP passes from the Ingress node to the Egress node in order, and the status is “Success (FRR ) ”“ Success (FRR, Backup) ”, node information and failure location information through which the LSP passes. In the case of RSVP-TE-LSP and the status is “Failure (Backup)”, “Failure (No Route)”, or “Failure (No Bandwidth)”, “no route” is set.

  When the LSP is other than RSVP-TE-LSP, it is node information through which the LSP passes. When communication is disconnected due to a failure or the like, “no route” is set.

  Step 103) Next, the information acquisition unit 110 acquires the individual traffic information of the traffic group that is communicating on the network, and stores it in the information storage unit 170. The traffic information includes an ID number, a traffic type, a source node, a destination node, and a usage route. Here, the use route is node information through which traffic passes, and is “no route” when communication is disconnected due to a failure or the like.

  Step 104) Next, the information acquisition unit 110 acquires FEC information that associates the LSP and the MPLS traffic set in the network, and stores them in the information storage unit 170. The FEC information includes information associating the ID number of the LSP and the traffic ID number.

  Step 105) Next, the information acquisition unit 110 acquires failure location information and stores it in the information storage unit 170. The failure location information is represented by a failure node or a failure link.

  Step 106) In the LSP classification unit 121 of the RSVP-TE-LSP route calculation unit 120, the LSP information acquired by the information acquisition unit 110 and stored in the information storage unit 170 and the failure occurrence location information are referred to. Classification is performed, and the classified information is stored in the LSP classification storage unit 124. The LSP classification process is shown below.

  FIG. 7 is a flowchart of LSP classification processing according to the first embodiment of this invention.

  Here, among the affected RSVP-TE-LSP groups, the RSVP-TE-LSP group that passes through the location of the failure changes to Group A, and among the affected RSVP-TE-LSP groups, changes from the failed state to the successful state An RSVP-TE-LSP group that may be affected is group B, an unaffected RSVP-TE-LSP group is group C, and an LSP group other than RSVP-TE is group D.

  First, the LSP classification unit 121 determines whether the LSP is an RSVP-TE LSP or not for the LSP information acquired from the information storage unit 170 (step 201). When the LSP is not an RSVP-TE LSP (No in step 201), the LSP is determined to be a group D. In the case of RSVP-TE LSP (step 201, Yes), the process proceeds to the next step.

  Next, when the state of the LSP is “Failure (No Route)” (step 202, Yes), it is determined as group C. Otherwise (step 202, No), the process proceeds to the next step.

  Next, when the state of the LSP is “Failure (No Bandwidth)” (step 203, Yes), it is determined as the group B. If not (step 203, No), the process proceeds to the next step.

  Next, when the failure occurrence location acquired from the information storage unit 170 is on the LSP usage route (step 204, Yes), it is determined as group A. Otherwise (step 204, No), it is determined as group C. To do.

  When the group is determined, the LSP information is stored in the LSP classification storage unit 124 for each group.

  Step 107) Next, the unaffected LSP calculation unit 122 refers to the LSP classification storage unit 124 and stores the LSP information of all LSPs of the group C, that is, the unaffected RSVP-TE-LSP group, in the calculated LSP storage. Stored in the unit 180.

  Step 108) Next, the unaffected LSP calculation unit 122 refers to the use path and the requested bandwidth of each LSP of group C, adds the reserved bandwidth to the link through which the LSP passes, and sets the reserved bandwidth for each link as the reserved bandwidth. Save in the storage unit 125. When the use route is “no route”, the reserved bandwidth is not added. Here, if the topology information acquired in step 101 and stored in the information storage unit 170 includes the reserved bandwidth information for each link, which is the sum of the required bandwidths of all LSPs, Rather than adding the required bandwidth of the C LSP, a process of referring to the individual usage routes of the groups A and B, that is, the affected LSP, and subtracting the required bandwidth of the LSP from the link of the usage route You may go.

  Step 109) Next, in the affected LSP calculation unit 123, the LSP classification storage unit 124 is referred to, and the group A, that is, the affected RSVP-TE-LSP group, RSVP-TE- One LSP that has not yet been calculated is extracted from the LSP group, and a new usage route and a new state are determined. The operation is shown below.

  8 and 9 are flowcharts of the new usage route and new state determination operation of the LSP of group A in the first embodiment of this invention.

  It is determined whether the LSP is Bypass, Detour, or Backup (step 301). In the case of Bypass, Detour, or Backup (step 301, Yes), the path from the Ingress (PLR) node to the Egress (MP) node is calculated in the topology with the acquired failure location removed (step 302). Here, the Strict designation section checks whether or not there is a designated node and a link connecting them. In the Loose specified section, it is checked whether a route exists between the specified nodes by the shortest route calculation by IGP. The calculation result is temporarily stored in a memory or the like.

  If the result of the route calculation is “no route” (step 303, No), the new state of the LSP is “Failure (No Route)” and the new usage route is “no route” (step 304). As a result of the route calculation, if there is a route, but there is a reserved bandwidth over location on the route (Yes in step 305), the new state of the LSP is “Failure (No Bandwidth)” and the new usage route is “no route” (Step 306). As a result of the route calculation, when there is a route (step 303, Yes) and there is no reserved bandwidth over location on the route (step 305, No), the new state of the LSP is set to “Success” and the route obtained by the route calculation Is a new usage route (step 307).

  Next, when the LSP is not Bypass, Detour or Backup (step 301, No), the route calculation is performed (step 308) as described above, there is a route (step 309, Yes), and there is no reserved bandwidth over location (step 308). In step 310, No), the new state of the LSP is set to “Success”, and the route obtained by the route calculation is set as the new usage route (step 311).

  If there is no route (step 309, No), or if there is a route but there is a reserved bandwidth over location (step 310, Yes), the FRR is set at the acquired failure occurrence location in the LSP, and Then, it is determined whether the Bypass or Detour belongs to the group C and is in the “Success” state (step 312). If so, it is determined whether Backup is set in the LSP, the Backup belongs to the group C, and is in the “Success” state (step 313). If so (Yes in Step 313), the new state of the LSP is set to “Success (FRR, Backup)”, and the acquired failure location information is added to the usage route to form a new usage route (Step 314). If Backup is not set for the LSP, or if the Backup does not belong to group C and is not in the “Success” state (step 313, No), the new state of the LSP is set to “Success (FRR)” and the usage route In addition, the acquired failure location information is added to form a new usage route (step 315).

  In the LSP, if the FRR is not set for the acquired failure location, or if the Bypass or Detour does not belong to the group C and is not in the “Success” state (No in step 312), Backup is set for the LSP. Whether the backup belongs to group C and is in the “Success” state is determined (step 316). If so (Yes in step 316), the new usage route of the LSP is set to “Failure (Backup)” and the new usage route is set to no route (step 317). Otherwise (step 316, No), it is determined whether there is a route and there is a reserved bandwidth over location (step 318). If so (step 318, Yes), the new state of the LSP is set to “Failure (No Bandwidth)”, and the new usage route is set to no route (step 319). If there is no route (step 318, No), the new state of the LSP is set to “Failure (No Route)”, and the new usage route is set to no route (step 320).

  Step 110) Next, the affected LSP calculation unit 123 stores, in the calculated LSP storage unit 180, the LSP information in which the usage route and state are updated to the new usage route and the new state for the above LSP.

  Step 111) The affected LSP calculation unit 123 refers to the new usage route, the new state, and the requested bandwidth, adds the reserved bandwidth to the link through which the LSP passes, and stores the reserved bandwidth for each link in the reserved bandwidth storage unit 125. . Here, when the new states are “Success (FRR, Backup)” and “Success (FRR)”, the bandwidth is added to the link of the route excluding the failure part. In the case of a node failure, the path is the path from which the fault node and the nodes at both ends of the fault node are removed, and in the case of a link fault, the path is the path from which the link is removed. When the new usage route is no route, the band is not added.

  Step 112) Until all the LSPs of group A are stored in the calculated LSP storage unit 180, determination of the new usage route and new state (step 109), storage in the calculated LSP storage unit 180 (step 110), reserved bandwidth The calculation process (step 111) is repeated.

  Step 113) Next, the affected LSP calculation unit 123 refers to the LSP classification storage unit 124, and may change from the failed state to the successful state among the group B, that is, the affected RSVP-TE-LSP group. One LSP that has not yet been calculated is extracted from a certain RSVP-TE-LSP group, and a new usage route and a new state are determined. The operation is shown below.

  FIG. 10 is a flowchart of the new use path and new state determination operation for the LSP of group B in the first embodiment of this invention.

  Similarly to the above, the affected LSP calculation unit 123 performs route calculation (step 401). If there is a route and there is a reserved bandwidth over location (steps 402, 403, Yes), the new state of the LSP is “Failure (No Bandwidth)”, and the new usage route is no route (step 404). ). When there is a route (step 402, Yes) and there is no reserved bandwidth over location (step 403, No), the new state of the LSP is set to “Success” and the route obtained by the route calculation is used as the new usage route. (Step 405). If there is no route, the new state of the LSP is set to “Failure (No Route)”, and the new usage route is set to no route (step 406).

  Step 114) The affected LSP calculation unit 123 stores, in the calculated LSP storage unit 180, the LSP information in which the usage route and state of the LSP are updated to the new usage route and the new state.

  Step 115) Next, the affected LSP calculation unit 123 refers to the new usage route, the new state, and the requested bandwidth, and adds the reserved bandwidth to the link through which the LSP passes in the same manner as described above, and determines the reserved bandwidth for each link. Stored in the reserved bandwidth storage unit 125.

  Step 116) Until all the LSPs of group B are stored in the calculated LSP storage unit 180, the new route and new state determination process (step 113), storage in the calculated LSP storage unit 180 (step 114), reservation The bandwidth calculation process (step 115) is repeated.

  Step 117) The LSP route calculation unit 130 refers to the LSP classification storage unit 124, extracts one LSP that has not yet been calculated from the group D, that is, the LSP group other than RSVP-TE, and calculates a new usage route. To do. In the topology excluding the acquired failure location, IGP calculates the shortest route from the Ingress node to the Egress node. If there is a route, the route is regarded as a new route, and if there is no route, the route is regarded as no route. To do. The usage route of the LSP information is updated to the new usage route and stored in the calculated LSP storage unit 180. Until all the LSPs of the group D are stored in the calculated LSP storage unit 180, the process of calculating the new usage route and storing in the calculated LSP storage unit 180 is repeated.

  Step 118) Next, the MPLS traffic route calculation unit 140 refers to the information storage unit 170, and extracts one MPLS traffic that has not been calculated yet for traffic whose traffic type is MPLS traffic from the traffic group. , Calculate new usage routes. The new usage route calculation method is as follows.

  First, the FEC information in the information storage unit 170 is referred to, and the ID number of the LSP associated with the MPLS traffic ID number is acquired. The calculated LSP storage unit 180 is referred to, and the new usage path of the LSP having the acquired ID number is referred to as the new usage path of the MPLS traffic. However, if the LSP associated with the MPLS traffic is RSVP-TE-LSP and the new state of the LSP is `` Success (FRR) '', the new usage route of the LSP and the LSP The combined use path of Bypass or Detour LSP that has been set is used as the new use path of the MPLS traffic, and in the case of `` Success (FRR, Backup) '' and `` Failure (Backup) '', it is set to that LSP. The new usage route of Backup LSP is used as the new usage route of the MPLS traffic. The usage route of the traffic information is updated to the new usage route and stored in the calculated traffic storage unit 190. Until all the MPLS traffic is stored in the calculated traffic storage unit 190, the calculation of the new usage route and the storage in the calculated traffic storage unit 190 are repeated.

  Step 119) Next, in the IP traffic route calculation unit 150, one IP traffic that has not yet been calculated for the traffic whose traffic type is IP traffic is extracted from the information storage unit 170. Calculate usage routes. In the topology excluding the location where the failure occurred in step 105, the shortest route calculation is performed by IGP from the source node to the destination node. If there is a route, the route is used as a new route, and if there is no route, a new route is used. The route is assumed to be no route. The usage route of the traffic information is updated to the new usage route and stored in the calculated traffic storage unit 190. Until all the IP traffic is stored in the calculated traffic storage unit 190, the calculation of the new usage route and the storage in the calculated traffic storage unit 190 are repeated.

  Step 120) Finally, the route output unit 160 outputs the use route for each LSP and traffic stored in the calculated LSP storage unit 180 and the calculated traffic storage unit 190, and ends the processing.

  According to the first embodiment, it is possible to correctly estimate a change in path when a failure occurs in a network in which MPLS and IP are mixed.

[Second Embodiment]
In the present embodiment, route estimation at the time of failure recovery will be described.

  The route estimation apparatus according to the present embodiment has the same configuration as the route estimation apparatus according to the first embodiment described above, and will be described below with reference to FIG.

  The operation in the present embodiment will be described below. In the present embodiment, it is assumed that one failure location exists in the network, and the failure location is restored.

  The following operation will be described with reference to FIGS.

  Step 101) First, the information acquisition unit 110 acquires topology information representing the connection relationship of each node of the network, and stores it in the information storage unit 170. The topology information includes the metric value and bandwidth of each link in addition to the connection relationship of each node.

  Step 102) Next, the individual setting information of the LSP group connected to the network, the LSP information indicating the usage route and the state are acquired and stored in the information storage unit 170. Here, in the LSP information, in addition to the RSVP-TE and LDP Primary LSP used as the main route, the Detour LSP, Bypass LSP, and Backup LSP set as the FRR route are handled independently as one RSVP-TE-LSP. The LSP setting information in the LSP information includes ID number, LSP type, Ingress (PLR) node, Egress (MP) node, requested route (only for RSVP-TE-LSP), requested bandwidth (for RSVP-TE-LSP) Only) and protection method (only for RSVP-TE-LSP Primary LSP). Here, in this embodiment, it is assumed that there are two types of LSP types, RSVP-TE and LDP. The state in the LSP information has the same definition as in the first embodiment. The RSVP passes information from the Ingress node to the Egress node in order, and if the status is "Success (FRR)" or "Success (FRR, Backup)", the RSVP is the node information and failure location information that the LSP passes In the case of -TE-LSP and the status is “Failure (Backup)”, “Failure (No Route)”, or “Failure (No Bandwidth)”, “no route” is set. When the LSP is other than RSVP-TE-LSP, it is node information through which the LSP passes. When communication is disconnected due to a failure or the like, “no route” is set.

  Step 103) Next, the information acquisition unit 110 acquires the individual traffic information of the traffic group communicating with the network, and stores it in the information storage unit 170. The traffic information includes an ID number, a traffic type, a source node, a destination node, and a usage route. Here, the usage route is node information through which traffic passes, and is “no route” when communication is disconnected due to a failure or the like.

  Step 104) Next, the information acquisition unit 110 acquires FEC information that associates the LSP and MPLS traffic set in the network, and stores them in the information storage unit 170. The FEC information includes information associating the ID number of the LSP and the traffic ID number.

  Step 105) Next, the information acquisition unit 110 acquires failure recovery point information and stores it in the information storage unit 170. The failure recovery location information is represented by a recovery node or a recovery link.

  Step 106) The LSP classification unit 121 of the RSVP-TE-LSP route calculation unit 120 refers to the LSP information acquired in Step 102 and the failure location information acquired in Step 105 and stored in the information storage unit 170. , LSP classification. The LSP classification method in this embodiment will be described below.

  FIG. 11 is a flowchart of the LSP classification operation in the second embodiment of the present invention.

  Here, among the affected RSVP-TE-LSP groups, group RSVP-TE-LSPs in the `` Success '', `` Success (FRR) '', and `` Success (FRR, Backup) '' states whose routes are changed by failure recovery. A. Among affected RSVP-TE-LSP groups, LSPs in the "Failure (No Route)", "Failure (No Bandwidth)" and "Failure (Backup)" states that may change from a failed state to a successful state Are group B, unaffected RSVP-TE-LSP groups are group C, and LSP groups other than RSVP-TE are group D.

  First, the LSP classification unit 121 determines whether the LSP of the LSP information stored in the information storage unit 170 is an RSVP-TE LSP (step 501). When the LSP is not an RSVP-TE LSP (step 501, No), the LSP is determined to be group D (step 502).

  In the case of an RSVP-TE LSP (step 501, Yes), the LSP state is “Failure (No Route)”, “Failure (No Bandwidth)”, or “Failure (Backup)” (step 503). Yes), group B is determined (step 504). If not (No in Step 503), the path from the Ingress (PLR) node to the Egress (MP) node is calculated in the topology in which the acquired failure recovery location is returned (Step 505). Here, the Strict designation section checks whether or not there is a designated node and a link connecting them. In the Loose designation section, it is checked whether a route exists between the designated nodes by the shortest route calculation by IGP. When the route obtained as a result of the calculation is different from the LSP usage route, or when the failure location on the LSP is restored (Yes in step 506), the group A is determined (step 507). Otherwise (step 506, No), it is determined as group C (step 508).

  Step 107) In the unaffected LSP calculation unit 122, the LSP classification storage unit 124 is referred to, and the LSP information is calculated in the calculated LSP storage unit 180 for all LSPs of the group C, that is, the RSVP-TE-LSP group that is not affected. Store.

  Step 108) The unaffected LSP calculation unit 122 refers to the use path and the requested bandwidth of each LSP of group C, adds the reserved bandwidth to the link through which the LSP passes, and sets the reserved bandwidth for each link as the reserved bandwidth storage unit 125. Save to. When the use route is “no route”, the reserved bandwidth is not added. Here, if the topology information acquired in step 101 and stored in the information storage unit 170 includes the reserved bandwidth information for each link that includes the requested bandwidths of all LSPs, Rather than adding the required bandwidth of the SLP of C, the processing is performed by referring to the individual usage routes of the groups A and B, that is, the affected LSP, and subtracting the required bandwidth of the LSP from the link of the usage route. May be.

  Step 109) Next, in the affected LSP calculation unit 123, the LSP classification storage unit 124 is referred to, and among the affected RSVP-TE-LSP groups, the RSVP- in which the route is changed due to failure recovery. One LSP that has not yet been calculated is extracted from the TE-LSP group, and a new usage route and a new state are determined. The operation will be described below.

  FIG. 12 is a flowchart of the new use path and new state determination operation for the LSP of group A in the second embodiment of this invention.

  First, as described above, the LSP route calculation unit 130 performs route calculation in the topology in which the acquired failure recovery location is returned (step 601). The path always exists because the fault is restored. If there is no reserved bandwidth over location (step 602, No), the new state of the LSP is set to “Success”, and the route obtained by the route calculation is set as the new usage route (step 603).

  If there is a reserved bandwidth over location (step 602, Yes), it is determined whether the LSP status is "Success (FRR)" (step 604). If so (step 604, Yes), the new state of the LSP is set to “Success (FRR)”, and the failure location of the usage route is set as the reserved bandwidth over location as the new usage route (step 605). If the LSP state is not “Success (FRR)” (step 604, No), it is determined whether the LSP state is “Success (FRR, Backup)” (step 606). If so (step 606, Yes), the new state of the LSP is set to “Success (FRR, Backup)”, and the failure location of the usage route is set as the reserved bandwidth over location as the new usage route (step 607). When the LSP is not “Success (FRR, Backup)”, the new state of the LSP is “Failure (No Bandwidth)”, and the new usage route is “no route” (step 608).

  Step 110) Next, in the affected LSP calculation unit 123, the LSP information obtained by updating the LSP usage route and state obtained above to the new usage route and the new state is stored in the calculated LSP storage unit 180.

  Step 111) The affected LSP calculation unit 123 refers to the new usage route, new state, and requested bandwidth of the calculated LSP storage unit 180, adds the reserved bandwidth to the link through which the LSP passes, and reserves the reserved bandwidth for each link. Stored in the bandwidth storage unit 125. Here, when the new states are “Success (FRR, Backup)” and “Success (FRR)”, the bandwidth is added to the link of the route excluding the reserved bandwidth excess portion. In the case of a node failure, the route except for the failure node and the nodes at both ends of the failure node on the route, and in the case of a link failure, the route on which the link on the route is removed. When the new usage route is no route, the band is not added.

  Step 112) Until all the LSPs of group A are stored in the calculated LSP storage unit 180, determination of the new usage route and new state (step 109), storage in the calculated LSP storage unit 180 (step 110), reserved bandwidth The calculation process (step 111) is repeated.

  Step 113) Next, the affected LSP calculation unit 123 refers to the LSP classification storage unit 124, and may change from the failed state to the successful state among the group B, that is, the affected RSVP-TE-LSP group. One LSP that has not yet been calculated is extracted from a certain RSVP-TE-LSP group, and a new usage route and a new state are determined. The operation is shown below.

  FIG. 13 is a flowchart of the new use path and new state determination operation for group B in the second embodiment of the present invention.

  First, the affected LSP calculation unit 123 determines whether or not the LSP is “Failure (Backup)” (step 701). If “Failure (Backup)”, the same route calculation as described above is performed (step 702), and it is determined whether or not there is a reserved bandwidth over location (step 703). If there is no reserved bandwidth over location (No in Step 703), the new state of the LSP is set to “Success”, and the route obtained by the route calculation is set as the new usage route (Step 704). If there is a reserved bandwidth over location (step 703, Yes), the new state of the LSP is “Failure (Backup)”, and the new usage route is “no route” (step 705).

  Next, when the LSP is not “Failure (Backup)” (No in Step 701), the same route calculation is performed (Step 706), and it is determined whether there is a route (Step 707). If there is a route and there is no reserved bandwidth over location (step 708, No), the new state of the LSP is set to “Success”, and the route obtained by the route calculation is set as a new use route (step 709). If there is a reserved bandwidth over location (step 708, Yes), the new state of the LSP is set to “Failure (No Bandwidth)”, and the new usage route is set to “no route” (step 710). When there is no route in the route calculation (step 707, No), the new state of the LSP is set to “Failure (No Route)”, and the new usage route is set to “no route” (step 711).

  Step 114) Next, the affected LSP calculation unit 123 stores, in the calculated LSP storage unit 180, the LSP information updated to the usage route and state, the new usage route and the new state for the LSP.

  Step 115) Next, the affected LSP calculation unit 123 refers to the new usage route, new state, and requested bandwidth of the calculated LSP storage unit 180, and adds the reserved bandwidth to the link through which the LSP passes, as described above. Each reserved bandwidth is stored in the storage unit 125.

  Step 116) In the affected LSP calculation unit 123, until all the LSPs of the group B are stored in the calculated LSP storage unit 180, the new usage route and the new state are determined (step 113), and the calculated LSP storage unit 180 is updated. The storage (step 114) and reserved band calculation processing (step 115) are repeated.

  Step 117) Next, the LSP route calculation unit 130 extracts one LSP that has not yet been calculated from the group D, that is, the LSP group other than RSVP-TE, from the LSP classification storage unit 124, and calculates a new usage route. To do. In the topology where the failure recovery location acquired in step 105 is returned, the shortest route calculation is performed by IGP from the Ingress node to the Egress node. If there is a route, the route is set as a new usage route. “No route”. The usage route of the LSP information is updated to the new usage route and stored in the calculated LSP storage unit 180. Until all the LSPs of group D are stored in the calculated LSP storage unit 180, the process of calculating the new usage route and storing in the calculated LSP storage unit 180 is repeated.

  Subsequent MPLS traffic route calculation (step 118), IP traffic route calculation (step 119), and route output processing (step 120) are the same as those in the first embodiment. However, the topology used in each route calculation process is a topology in which the acquired failure recovery location is returned.

  According to the second embodiment described above, it is possible to correctly estimate a change in path when a failure is recovered in a network in which MPLS and IP are mixed.

  The operations of the first and second embodiments described above can be constructed as a program and installed in a computer used as a route estimation device for execution, or distributed via a network.

  Further, the constructed program can be stored in a portable storage medium such as a computer-readable disk device or a flexible disk / CD-ROM, and installed in a computer to be executed or distributed.

  The present invention is not limited to the above-described embodiment, and various modifications and applications can be made within the scope of the claims.

  The present invention can be applied to a technique for simulating a situation at the time of failure occurrence or failure recovery in a network in which RSVP-TE LSPs and the like are mixed and FRR and Backup LSP are set.

It is a figure for demonstrating the principle of this invention. It is a principle block diagram of this invention. It is a block diagram of the system | strain estimation apparatus at the time of the failure occurrence in the 1st and 2nd embodiment of this invention, or a failure recovery. It is the flowchart (the 1) of the operation | movement in the 1st and 2nd embodiment of this invention. It is a flowchart (the 2) of the operation | movement in the 1st and 2nd embodiment of this invention. It is the state of RSVP-TE-LSP in the first and second embodiments of the present invention. It is a flowchart of the LSP classification | category operation | movement in the 1st Embodiment of this invention. It is a flowchart (the 1) of the determination operation | movement of the new utilization path | route and new state of LSP of the group A in the 1st Embodiment of this invention. It is a flowchart (the 2) of the determination operation | movement of the new utilization path | route and new state of LSP of the group A in the 1st Embodiment of this invention. It is a flowchart of the determination operation | movement of the new utilization path | route and new state of the group B in the 1st Embodiment of this invention. It is a flowchart of the LSP classification | category operation | movement in the 1st Embodiment of this invention. It is a flowchart of the determination operation | movement of the new utilization path | route and new state of LSP of the group A in the 2nd Embodiment of this invention. It is a flowchart of the determination operation | movement of the new utilization path | route and new state of LSP of the group B in the 2nd Embodiment of this invention. FRR classification.

Explanation of symbols

110 Information acquisition means, information acquisition section 120 RSVP-TE-LSP route calculation means 121 LSP classification means, LSP classification section 122 Unaffected LSP calculation means, Unaffected LSP calculation section 123 Influential LSP calculation means, Influential LSP calculation section 124 LSP classification storage unit, LSP classification storage unit 125 Reserved bandwidth storage unit 130 LSP route calculation unit, LSP route calculation unit 140 MPLS traffic route calculation unit, MPLS traffic route calculation unit 150 IP traffic route calculation unit, IP traffic route calculation unit 160 Output unit, route output unit 170 Information storage unit, information storage unit 180 Calculated LSP storage unit, Calculated LSP storage unit 190 Calculated traffic storage unit, Calculated traffic storage unit

Claims (13)

IP (Internet Protocol) routing including Open Shortest Path First (OSPF), and MPLS (Multi Protocol Label Switching) networks that operate Resource Reservation Signaling Protocol for Traffic Engineering (RSVP-TE) and Label Distribution Protocol (LDP) (Label Switched Path) and an alternate route including FRR (Fast Reroute) and Backup LSP is set in the LSP, and a failure has occurred in a link or node under the situation where IP and MPLS traffic communication is performed It is a route estimation method at the time of failure that estimates the LSP and traffic route change in case,
The information acquisition means communicates topology information that represents the connection relationship of each node of the network, LSP information that indicates individual setting information, usage route, and status of LSP groups that are set in the network, and communication. Information acquisition step for acquiring the traffic information, FEC (Forwarding Equivalence Class) information for associating the LSP and MPLS traffic, and failure occurrence position information indicating the position information of the failure occurrence location, and storing the information in the information storage means;
RSVP-TE-LSP route calculating means refers to the information storage means, acquires LVP information of RSVP-TE among the LSP information, calculates a change in the route due to the occurrence of a failure, and uses a new route of the LSP RSVP-TE-LSP path calculation step for storing the state in the calculated LSP storage means,
LSP route calculation means refers to the information storage means, acquires LSP information other than RSVP-TE among the LSP information, calculates a change in the route due to the occurrence of a failure, and determines the new usage route and state of the LSP LSP path calculation step for storing in the calculated LSP storage means;
MPLS traffic path calculation means obtains MPLS traffic information from among the traffic information stored in the information storage means, refers to the FEC information stored in the information storage means, and associates with MPLS traffic An MPLS traffic path calculation step of acquiring a new usage path of the LSP being stored from the calculated LSP storage means, and storing the new usage path as a new usage path of the MPLS traffic in the calculated traffic storage means;
IP traffic route calculation means obtains IP traffic information from the traffic information stored in the information storage means, calculates a change in the route due to the occurrence of a failure, and calculates a new usage route of the IP traffic. An IP traffic route calculation step stored in the storage means;
A path output step for outputting a path for each LSP and traffic stored in the calculated LSP storage means and the calculated traffic storage means;
A route estimation method characterized by performing: In the RSVP-TE-LSP route calculation step,
LSP classification means refers to the RSVP-TE LSP information in the information storage means, classifies the LSP group affected by the occurrence of a failure and the LSP group not affected by the occurrence of the failure, and classifies together with the LSP information. LSP classification step for storing in the LSP classification storage means for each,
An unaffected LSP calculation means acquires an LSP group that is not affected by the occurrence of the failure from the LSP classification storage means, and stores the LSP group in the calculated LSP storage means together with the LSP information; and ,
The affected LSP calculation means obtains one LSP that has not been calculated yet with reference to the calculated LSP storage means from among the LSP groups affected by the occurrence of the failure from the LSP classification storage means, The LSP information of the LSP and the failure occurrence position information are referred to, a new usage route and a state are calculated, and the LSP is stored in the calculated LSP storage unit together with the new LSP information.
Repeat the affected LSP calculation step until it is no longer possible to obtain LSPs that have not been calculated,
The route estimation method according to claim 1. When performing route estimation when a failure occurs at a certain point,
In the LSP classification step of the RSVP-TE-LSP route calculation step,
The LSP groups that are affected by the occurrence of the failure are further classified into an LSP group in which the usage route in the LSP information passes through the failure occurrence location and an LSP group that may change from a failure state to a success state. , Stored in the LSP classification storage unit for each classification together with the LSP information,
In the affected LSP calculation step of the RSVP-TE-LSP route calculation step,
The LSP group in which the usage route in the LSP information passes through the failure occurrence point is calculated first, and the LSP group that may change from the failed state to the successful state is calculated later.
The route estimation method according to claim 1 or 2. In an IP routing including OSPF, and an MPLS network in which RSVP-TE and LDP operate, an LSP and an alternative route including FRR and Backup LSP are set in the LSP, and IP and MPLS traffic communication is performed. In the failure recovery route estimation method for estimating the LSP and traffic route change when a certain link or node failure is recovered,
The information acquisition means communicates topology information that represents the connection relationship of each node of the network, LSP information that indicates individual setting information, usage route, and status of LSP groups that are set in the network, and communication. Information acquisition step for acquiring traffic recovery information, FEC information for associating the LSP and MPLS traffic, and fault recovery position information indicating the position information of the fault recovery point, and storing the information in the information storage means;
RSVP-TE-LSP route calculating means refers to the information storage means, acquires LVP information of RSVP-TE among the LSP information, calculates a change in route due to failure recovery, and uses a new route of the LSP RSVP-TE-LSP path calculation step for storing the state in the calculated LSP storage means,
The LSP route calculation means acquires LSP information other than RSVP-TE among the LSP information stored in the information storage means, calculates the change of the route due to failure recovery, and uses the new LSP route and status of the LSP LSP path calculation step for storing the calculated LSP in the calculated LSP storage means;
MPLS traffic path calculation means obtains MPLS traffic information from among the traffic information stored in the information storage means, refers to the FEC information stored in the information storage means, and associates with MPLS traffic An MPLS traffic path calculation step of acquiring a new usage path of the LSP being stored from the calculated LSP storage means, and storing the new usage path as a new usage path of the MPLS traffic in the calculated traffic storage means;
The IP traffic route calculation means acquires the IP traffic information from the traffic information stored in the information storage means, calculates the route change due to failure recovery, and has already calculated the new IP traffic usage route IP traffic route calculation step for storing in the traffic storage means;
A path output step for outputting a path for each LSP and traffic stored in the calculated LSP storage means and the calculated traffic storage means;
A route estimation method characterized by performing: In the RSVP-TE-LSP route calculation step,
The LSP classification means refers to the RSVP-TE LSP information stored in the information storage means, classifies the LSP group affected by failure recovery, and the LSP group not affected by failure recovery, LSP classification step for storing in LSP classification storage means for each classification together with LSP information;
An unaffected LSP calculation means acquires an LSP group that is not affected by failure recovery from the LSP classification storage means, and stores the LSP group in the calculated LSP storage means together with the LSP information; and
The affected LSP calculation means obtains one LSP that has not been calculated yet by referring to the calculated LSP storage means from the LSP group that is affected by the failure recovery of the LSP classification storage means. The LSP information and the failure recovery position information are referred, a new usage route and state are calculated, and the LSP is stored in the calculated LSP storage means together with the new LSP information.
Repeat the affected LSP calculation step until it is no longer possible to obtain LSPs that have not been calculated,
The route estimation method according to claim 4. When performing route estimation when a failure is recovered at one location,
In the LSP classification step of the RSVP-TE-LSP route calculation step,
The LSP group affected by the failure recovery is further classified into an LSP group in which a use route in the LSP information changes due to failure recovery, and an LSP group that may change from a failure state to a success state, Store in the LSP classification storage means for each classification together with the LSP information,
In the affected LSP calculation step of the RSVP-TE-LSP route calculation step,
The LSP group in which the usage route in the LSP information changes due to failure recovery is calculated first, and the LSP group that may change from a failed state to a successful state is calculated later.
The route estimation method according to claim 4 or 5. In an IP routing including OSPF, and an MPLS network in which RSVP-TE and LDP operate, an LSP and an alternative route including FRR and Backup LSP are set in the LSP, and IP and MPLS traffic communication is performed. In the failure occurrence route estimation device that estimates the LSP and traffic route change when a failure occurs in a certain link or node,
Topology information representing the connection relationship of each node of the network, individual setting information of LSP groups set in the network, LSP information representing the use route and state, traffic information on which communication is performed, and FEC information for associating the LSP and MPLS traffic, and failure occurrence position information indicating the location information of the failure occurrence location, information acquisition means for storing in the information storage means,
Refers to the information storage means, acquires RSVP-TE LSP information of the LSP information, calculates a change in path due to the occurrence of a failure, and stores the new used path and state of the LSP in the calculated LSP storage means RSVP-TE-LSP route calculation means to
Referring to the information storage means, acquiring LSP information other than RSVP-TE among the LSP information, calculating a change in path due to the occurrence of a failure, and calculating a new use path and state of the LSP in the calculated LSP storage means LSP route calculation means for storing,
Of the traffic information stored in the information storage means, obtain MPLS traffic information, refer to the FEC information stored in the information storage means, and use a new LSP associated with MPLS traffic An MPLS traffic route calculation means for obtaining a route from the calculated LSP storage means, and storing the new use route as a new use route of the MPLS traffic in the calculated traffic storage means;
IP traffic that obtains IP traffic information out of the traffic information stored in the information storage means, calculates a route change due to the occurrence of a failure, and stores a new usage route of the IP traffic in the calculated traffic storage means A route calculation means;
A route output means for outputting a route for each LSP and traffic stored in the calculated LSP storage means and the calculated traffic storage means;
A path estimation apparatus comprising: The RSVP-TE-LSP route calculation means is
Referring to the RSVP-TE LSP information of the information storage means, classify the LSP group affected by the failure occurrence and the LSP group not affected by the failure occurrence, and store the LSP classification for each classification together with the LSP information. LSP classification means stored in the means;
An LSP group that is not affected by the occurrence of the failure is acquired from the LSP classification storage unit, and the LSP group is stored in the calculated LSP storage unit together with the LSP information.
From the LSP classification storage means, one LSP that has not yet been calculated with reference to the calculated LSP storage means among the LSP groups affected by the occurrence of the failure, and the LSP information of the LSP and the LSP information Refers to failure location information, calculates new usage route and state, and stores the LSP in the calculated LSP storage means together with the new LSP information until there is no need to obtain an uncalculated LSP LSP calculation means,
The route estimation apparatus according to claim 7, comprising: When performing route estimation when a failure occurs at a certain point,
The LSP classification means of the RSVP-TE-LSP route calculation means is:
The LSP groups that are affected by the occurrence of the failure are further classified into an LSP group in which the usage route in the LSP information passes through the failure occurrence location and an LSP group that may change from a failure state to a success state. And means for storing in the LSP classification storage means for each classification together with the LSP information,
The affected LSP calculation means of the RSVP-TE-LSP route calculation means is:
Including means for calculating the LSP group in which the use path in the LSP information passes through the failure occurrence part first, and calculating the LSP group that may change from the failure state to the success state later,
The route estimation apparatus according to claim 7 or 8. In an IP routing including OSPF, and an MPLS network in which RSVP-TE and LDP operate, an LSP and an alternative route including FRR and Backup LSP are set in the LSP, and IP and MPLS traffic communication is performed. In the failure recovery route estimation device for estimating the LSP and traffic route change when a certain link or node failure is recovered,
Topology information representing the connection relationship of each node of the network, individual setting information of LSP groups set in the network, LSP information representing the use route and state, traffic information on which communication is performed, and FEC information for associating the LSP and MPLS traffic, and failure recovery location information indicating location information of the failure recovery location, information acquisition means for storing in the information storage means,
Refers to the information storage means, acquires RSVP-TE LSP information out of the LSP information, calculates path changes due to failure recovery, and stores new LSP usage paths and states in the calculated LSP storage means RSVP-TE-LSP route calculation means to
Of the LSP information stored in the information storage means, obtain LSP information other than RSVP-TE, calculate a change in path due to failure recovery, and calculate a new use path and state of the LSP LSP route calculation means to store in,
Of the traffic information stored in the information storage means, obtain MPLS traffic information, refer to the FEC information stored in the information storage means, and use a new LSP associated with MPLS traffic An MPLS traffic route calculation means for obtaining a route from the calculated LSP storage means, and storing the new use route as a new use route of the MPLS traffic in the calculated traffic storage means;
IP that obtains IP traffic information out of the traffic information stored in the information storage means, calculates a route change due to failure recovery, and stores a new usage route of the IP traffic in the calculated traffic storage means Traffic route calculation means,
A route output means for outputting a route for each LSP and traffic stored in the calculated LSP storage means and the calculated traffic storage means;
A path estimation apparatus comprising: The RSVP-TE-LSP route calculation means is
Refer to the LSP information of the RSVP-TE stored in the information storage means, classify into LSP groups that are affected by failure recovery and LSP groups that are not affected by failure recovery, together with the LSP information LSP classification means for storing in the LSP classification storage means,
From the LSP classification storage means, obtain an LSP group that is not affected by failure recovery, and store the LSP group together with the LSP information in the calculated LSP storage means, no influence LSP calculation means,
From the LSP group affected by the failure recovery of the LSP classification storage means, refer to the calculated LSP storage means to obtain one LSP that has not been calculated yet, and the LSP information of the LSP and the failure recovery Refers to location information, calculates new usage route and state, and stores the LSP in the calculated LSP storage means together with new LSP information until it becomes impossible to acquire an LSP that has not been calculated. Calculation means;
The route estimation apparatus according to claim 10, comprising: When performing route estimation when a failure is recovered at one location,
The LSP classification means of the RSVP-TE-LSP route calculation means is:
The LSP group affected by the failure recovery is further classified into an LSP group in which a use route in the LSP information changes due to failure recovery, and an LSP group that may change from a failure state to a success state, Means for storing in the LSP classification storage means for each classification together with the LSP information,
The affected LSP calculation means of the RSVP-TE-LSP route calculation means is:
Including means for calculating the LSP group in which the use path in the LSP information changes due to failure recovery first, and calculating the LSP group that may change from the failed state to the successful state later,
The route estimation apparatus according to claim 10 or 11. On the computer,
13. A route estimation program that causes each means of the route estimation device according to claim 7 to be executed.

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