WO2012163219A1 - Lsp network congestion processing method, device and system - Google Patents

Abstract

Provided are an LSP network congestion processing method, device and system. The method includes: a head node receiving a network congestion notification message sent by an intermediate node where congestion occurs, and the head node parsing the received network congestion notification message to obtain the address information and the congestion state information about the intermediate node, wherein a Path message sent does not pass by the intermediate node when the head node newly establishes an LSP. In addition, also provided are a corresponding LSP congestion processing device and system. As such, it is ensured that an LSP can be be established smoothly when network congestion occurs on the intermediate node, achieving the object of relieving the pressure on the intermediate node while ensuring LSP service, accelerating the convergence of the LSP, reducing the interrupt time of the traffic flow and improving the network dynamic balance.

Description

 Method, device and system for LSP network congestion processing

Technical field

 The embodiments of the present invention relate to the field of communications technologies, and in particular, to a method, a device, and a system for processing network congestion of a Label Switching Path (LSP).

Background technique

 The task of mapping traffic flows to the physical topology of the network is called Traffic Engineering (TE). By monitoring the traffic of the network and the load of the network unit in real time, the TE dynamically adjusts the traffic management parameters, routing parameters, and resource constraint parameters to migrate the network running state to an ideal state, optimize the use of network resources, and avoid congestion caused by uneven load.

With the expansion of the network and the improvement of the service quality requirements of the users, the LSPs in the TE application scenario are increasing, and more and more services are carried. When the number of LSPs in a TE network is large, users often do not configure hop-by-hop and strict display paths for each LSP. Instead, they use the resource constraints such as bandwidth and affinity attributes to plan the entire network. When the network topology changes, routing, LSP, and other services are deleted and reconstructed. The LSP is reconstructed based on the Constrained Shortest Path First (CSPF) path selection algorithm. The algorithm is easy to calculate. Both pass through the same intermediate node, causing network congestion. As shown in Figure 1, the head node Al ~ An establishes multiple TE LSPs to the tail nodes CI ~ Cm, which may pass through the intermediate node B1 or the intermediate node B2, and achieve the performance through automatic re-optimization and bandwidth adjustment in steady state. The LSP is evenly loaded into the network. However, if the network topology changes, it will cause routing, LSP and other services to be deleted and reconstructed. CSPF relies on the instantaneous calculation path. The best path that can be easily calculated passes through the same intermediate node. For example, Bl and B1 may also superimpose a large number of other services. The topology change will cause the services to be busy. When the system is busy, the B1 internals are caused. If the system is in a tight schedule and the CPU is too high, the system is congested. B1 does not urgently process the packets of a large number of newly created LSPs. The LSP convergence time is long, and the bearer service is interrupted. Longer problems, while B2 is idle and not being used effectively.

 The prior art solution generally adopts the following method: If the network congestion occurs in the intermediate node, the head node continuously sends a path (Path) message when the LSP is established. The network node is congested due to the network congestion of the intermediate node, and the LSP establishment fails. The period interval at which the head node sends the Path message is also gradually increased, for example, 2 seconds, 5 seconds, 10 seconds, 30 seconds, 60 seconds, and so on. This solution can gradually alleviate the pressure of the intermediate nodes that are congested. In the end, the LSPs can be successfully established. However, the intermediate nodes that are congested cannot be effectively avoided, and other available paths are selected. As a result, the LSP convergence is too slow and the service interruption time is long. Summary of the invention

 The embodiment of the invention provides a method, a device and a system for LSP network congestion processing. In a network with a large number of LSPs, when the network topology changes and the intermediate node is congested, the convergence of the LSP is accelerated, and the service flow interruption is reduced. Time has promoted the dynamic balance of the network.

 An embodiment of the present invention provides a method for LSP network congestion processing, where the method includes: a header node receives a network congestion notification message sent by an intermediate node that is congested; and the head node parses the received network congestion notification message. Obtaining address information of the intermediate node and congestion state information of the intermediate node;

 When the head node newly establishes an LSP, the path Path message sent does not pass through the intermediate node.

 An embodiment of the present invention provides an apparatus for LSP network congestion processing, where the apparatus includes: a receiving unit, configured to receive a network congestion notification message sent by an intermediate node that is congested; and a parsing unit, configured to parse the header node to receive The network congestion notification message, obtaining address information of the intermediate node and congestion state information of the intermediate node;

The processing unit finds the intermediate node data entry in the information database for establishing the LSP according to the obtained intermediate node address information, sets a congestion flag of the intermediate node data entry, and adds a Path message sent by the LSP. Does not pass through the intermediate node. An embodiment of the present invention provides a network congestion processing system, where the system includes: a head node network element device, configured to receive a network congestion notification message sent by an intermediate node that is congested, and congest the received network. Declaring the message, obtaining the address information and the congestion state information of the intermediate node, and finding the intermediate node data entry in the information database for establishing the LSP according to the obtained intermediate node address information, where the intermediate node is The data entry is set to be congested. When a new LSP is created, the sent Path message does not pass through the intermediate node. The intermediate node network element device is used to detect the congestion status. When the intermediate node network element device is congested, the network congestion is sent. The announcement message is sent to the head node network element device, where the network congestion advertisement message includes address information of the intermediate node network element device and congestion state information of the intermediate node.

 The method, device, and system for processing LSP network congestion according to the embodiment of the present invention, the head node may obtain the address and congestion of the intermediate node that is congested by receiving and parsing the congestion notification message sent by the intermediate node that is congested. State information, so that when the LSP is newly established, the intermediate node that is congested is selected in time to select other intermediate nodes that do not have congestion, and the LSP caused by the header message repeatedly sending an LSP to the intermediate node that has already been congested is overcome. A very slow problem is established, which achieves the purpose of easing the pressure of the intermediate node while guaranteeing the LSP service, speeding up the convergence of the LSP, reducing the interruption time of the traffic, and promoting the dynamic balance of the network.

DRAWINGS

 In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below. Obviously, the drawings in the following description It is a certain embodiment of the present invention, and other drawings can be obtained from those skilled in the art without any creative work.

 1 is a schematic diagram of a TE LSP network application in the prior art;

2 is a schematic diagram of a LSP network congestion processing method according to a first embodiment of the present invention; FIG. 3 is a schematic diagram of a PathErr message ERROR_SPEC format provided in an embodiment of the present invention; 4 is a schematic diagram of an LSP network congestion processing apparatus according to a second embodiment of the present invention; and FIG. 5 is a schematic diagram of an LSP network congestion processing system according to a third embodiment of the present invention. Concrete

 The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is a partial embodiment of the invention, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

 2 is a flow chart of a method according to a first embodiment of the present invention. Includes:

202. The head node receives a network congestion notification message sent by the intermediate node that is congested; the head node is a starting node of the LSP establishment process, and the intermediate node is a node on an intermediate path of the LSP establishment process. The network congestion notification message received by the head node may be constructed by extending the RSVP-TE protocol in a scenario of a resource reservation protocol (RT)-based traffic reservation protocol (RSVP-TE). During the establishment of the RSVP-TE LSP, the head node generates a Path message carrying the bandwidth reservation information and the path information, and sends the Path message to the intermediate node according to the path calculated by the CSFP. If the intermediate node generates an error during the processing of the Path message, it will send a Path Error (PathErr) message to the head node. The inter-issue node periodically detects the network congestion of the system. When the system is congested, a PathErr message of the type "Node Reroute Request" is constructed as a network congestion notification message for the Path message sent from the received slave node. The error description ( ERROR_SPEC ) in the PathErr message is as shown in Figure 3. See RFC5710. The error protocol (Internet Protocol version 4 Error Node Address, IPv4 Error Node Address) is the intermediate node address information for sending the congestion notification message PathErr message, and the error code (Error Code) is 34 for "Node Reroute". Request "type message, Error Value can be any of the agreed values in [32768, 65535], which indicates whether the system is Congestion has occurred.

 Or the network congestion message received by the head node is the routing information of the TE interface of the intermediate node, and the routing message is triggered by the TE interface of the middle node that changes the management weight (Metric) value, and is flooded by the IGP. . The intermediate node periodically detects the network congestion of the system. When the network is congested, the metric value of all the TE interfaces on the intermediate node is modified, which can be modified to a certain agreed value. The value is higher than other nodes. The Metric value on the TE interface is large, and can be modified to the maximum value OxFFFFFFFF. According to the IGP protocol, the route of the TE interface whose metric value is modified is flooded to the head node. Thus, in the specific implementation of the embodiment of the present invention, after the metric value of all the TE interfaces on the intermediate node is modified, the routes of all the TE interfaces of the intermediate node are flooded by way of routing messages. The head node, the routing message carries the TE interface address information of the intermediate node and the metric value, and the address information of the TE interface can be used as the address information of the identifier intermediate node.

 204. The head node parses the received network congestion notification message, and obtains address information of the intermediate node and congestion state information of the intermediate node.

 In the RSVP-TE scenario, the congestion notification message is constructed by the intermediate node carrying the intermediate node address information in the PathErr message of the response, and the head node receives the congestion notification message and parses the path according to the PathErr message structure. For the intermediate node address information in which congestion occurs, referring to FIG. 3, the IPv4 Error Node Address is the intermediate node address information. When the head node receives the congestion advertisement message of the type of the routing message, the address information of the intermediate node TE interface and the Metrric thereof may be obtained from the congestion notification message of the routing message type according to the optional manner of 202, and the Metric value is used as a judgment. A judgment flag of whether the intermediate node is congested, for example, when the Metric value is OxFFFFFFFF, the intermediate node is considered to send network congestion.

 206. When the head node newly establishes an LSP, the Path message sent does not pass through the intermediate node.

The head node of the TE deployed in the TE application network generates a data information base for establishing an LSP by using an Interior Gateway Protocol (IGP). The information base contains information about the entries of all intermediate nodes that are used to establish an LSP. The information of the entry contains information such as the address of the intermediate node. In the embodiment of the present invention, the head node may find an entry corresponding to the intermediate node in the data information base according to the address of the intermediate node that is congested and obtained by the parsing, and the table is The item sets the congestion tag. When the head node newly establishes an LSP, the Path message sent does not select the intermediate node that is congested, and selects an intermediate node in the information database that is not set with a congestion flag, thereby alleviating the middle while ensuring the LSP service. The purpose of node pressure is to speed up the convergence of LSPs, reduce the interruption time of traffic, and promote the dynamic balance of the network. Further, the head node may start a timer after the congestion of the intermediate node in which the congestion occurs, and the head node may start a timer. When the timer expires, the intermediate node that sets the congestion flag The congestion flag will be cleared, and the intermediate node will be used as the candidate inter-node of the LSP establishment path, and the intermediate node will receive the Path message for establishing the LSP sent by the head node. When the intermediate node is congested, the The LSP will be successfully established. When the intermediate node is still in a congested state, it continues to send a congestion notification message to the head node, and the head node continues the processing from 202 to 206.

 4 is a flow chart of a device according to a second embodiment of the present invention. The apparatus includes: a receiving unit 402, a parsing unit 404, and a processing unit 406.

 The receiving unit 402 is configured to receive, by the head node, a network congestion notification message sent by the intermediate node that is congested;

The network congestion notification message received by the receiving unit includes address information and congestion state information of the intermediate node. The network congestion notification message received by the receiving unit may be constructed by extending the RSVP-TE protocol in an RSVP-TE scenario. When the network congestion occurs in the system, the PathErr message of the type "Node Reroute Request" is constructed as a network congestion notification message for the Path message sent by the received slave node. The ERROR_SPEC in the constructed PathErr message is as shown in Figure 3. The structure shown. The IPv4 Error Node Address is an intermediate node address information for sending a congestion notification message PathErr message, and the Error Code is 34 for "Node Reroute Request," type message, and the Error Value may be any of [32768, 65535]. An agreed value that identifies whether the system is congested.

Or the network congestion message received by the receiving unit is the routing information of the TE interface of the intermediate node, and the routing message is triggered by the TE interface of the middle node that changes the metric value, and is flooded by the IGP. When the network of the intermediate node is congested, the metric value of all the TE interfaces on the intermediate node is modified, which can be modified to a certain agreed value, which is larger than the Metric value of the TE interface on other nodes. preferably may be modified in accordance with the maximum value 0xFFFFFFFF _o IGP protocol, routing modified TE interface Metric values will be flooded to the head node. Thus, in the specific implementation of the embodiment of the present invention, when the metric value of all the TE interfaces on the intermediate node is modified, the routes of all the TE interfaces of the intermediate node are flooded to the header by way of routing messages. The routing message carries the address information of the TE interface and the metric value, and the address information of the TE interface can be used as the address information of the intermediate node.

 The parsing unit 404 is configured to parse the network congestion notification message received by the head node, obtain address information of the intermediate node, and congestion state information of the intermediate node;

 In the scenario of the RSVP-TE, the congestion notification message is configured by the intermediate node responding to the PathErr by the Path message for establishing the LSP sent by the head node, and carrying the address information and the congestion state of the intermediate node in the response PathErr message. After the receiving unit receives the congestion notification message, the parsing unit parses the PathErr message to obtain the intermediate node address information and congestion status information of the congestion.

 When the receiving unit receives the congestion notification message of the routing message type, the parsing unit may obtain the address information of the intermediate node TE interface and the Metrric thereof from the congestion notification message of the routing message type, where the Metric value is used to determine whether the intermediate node occurs. The judgment flag of congestion, for example, when the Metric value is OxFFFFFFFF, the intermediate node is considered to transmit network congestion.

The processing unit 406 finds the intermediate node data entry in the information database for establishing the LSP according to the intermediate node address information obtained by the parsing unit, and sets the congestion parameter of the intermediate node data entry, and the new LSP is An intermediate node data entry that does not have a congestion flag is selected to avoid the intermediate node where congestion occurs. The processing unit finds the entry corresponding to the intermediate node in the data information base for establishing the LSP by using the matching search according to the address of the intermediate node that is congested by the parsing, and sets the entry to the congestion flag. When the head node newly establishes an LSP, the Path message sent does not select the intermediate node that is congested, and selects an intermediate node in the information database that is not set with a congestion flag, thereby alleviating the middle while ensuring the LSP service. The purpose of node pressure is to speed up the convergence of LSPs, reduce the interruption time of traffic, and promote the dynamic balance of the network.

 Figure 5 is a flow chart of the system of the third embodiment of the present invention. The system includes: a head node network element device 502 and an intermediate node network element device 504. The network element device may be a router, a switch, or other network device supporting the LSP.

 The head node network element device 502 is configured to receive a network congestion notification message sent by the intermediate node that is congested, and parse the received network congestion notification message to obtain address information and congestion state information of the intermediate node, according to the The obtained intermediate node address information finds the intermediate node data entry in the information database for establishing the LSP, and sets the intermediate node data entry to be congested. When the LSP is created, the sent Path message does not pass. The intermediate node;

 The intermediate node network element device 504 periodically detects the self-congestion condition, and sends a network congestion notification message to the head node network element device when the intermediate node network element device is congested, where the network congestion notification message includes the intermediate node network Address information of the metadevice and congestion state information of the intermediate node.

 The head node node network element device 502 includes:

 The receiving unit 402 is configured to receive, by the head node, a network congestion notification message sent by the intermediate node that is congested;

The network congestion notification message received by the receiving unit includes address information and congestion state information of the intermediate node. The network congestion notification message received by the receiving unit may be constructed by extending the RSVP-TE protocol in an RSVP-TE scenario. The intermediate node constructs a type of "Node" for the received Path message sent by the slave node when the network congestion occurs in the system. The PathErr message of the Reroute Request is used as the network congestion advertisement message, and the ERROR_SPEC in the constructed PathErr message is constructed as shown in Figure 3. The IPv4 Error Node Address is the intermediate node address information of the PathErr message for sending the congestion notification message, and the Error Code is 34. The Node Reroute Request, type message, Error Value can be any of the agreed values in [32768, 65535], which indicates whether the system is congested.

Or the network congestion message received by the receiving unit is the routing information of the TE interface of the intermediate node, and the routing message is triggered by the TE interface of the middle node that changes the metric value, and is flooded by the IGP. When the network of the intermediate node is congested, the metric value of all the TE interfaces on the intermediate node is modified, which can be modified to a certain agreed value, which is larger than the Metric value of the TE interface on other nodes. preferably may be modified in accordance with the maximum value 0xFFFFFFFF _o IGP protocol, routing modified TE interface Metric values will be flooded to the head node. Thus, in the specific implementation of the embodiment of the present invention, when the metric value of all the TE interfaces on the intermediate node is modified, the routes of all the TE interfaces of the intermediate node are flooded to the header by way of routing messages. The routing message carries the address information of the TE interface and the metric value, and the address information of the TE interface can be used as the address information of the intermediate node.

 The parsing unit 404 is configured to parse the network congestion notification message received by the head node, obtain address information of the intermediate node, and congestion state information of the intermediate node;

 In the scenario of the RSVP-TE, the congestion notification message is configured by the intermediate node responding to the PathErr by the Path message for establishing the LSP sent by the head node, and carrying the address information and the congestion state of the intermediate node in the response PathErr message. After the receiving unit receives the congestion notification message, the parsing unit parses the PathErr message to obtain the intermediate node address information and congestion status information of the congestion.

When the receiving unit receives the congestion notification message of the routing message type, the parsing unit may obtain the address information of the intermediate node TE interface and the Metrric thereof from the congestion notification message of the routing message type, where the Metric value is used to determine whether the intermediate node occurs. The judgment flag of congestion, for example, when the Metric value is OxFFFFFFFF, the intermediate node is considered to transmit network congestion. The processing unit 406 finds the intermediate node data entry in the information database for establishing the LSP according to the intermediate node address information obtained by the parsing unit, and sets the congestion parameter of the intermediate node data entry, and the new LSP is An intermediate node data entry that does not have a congestion flag is selected to avoid the intermediate node where congestion occurs.

 The processing unit finds the entry corresponding to the intermediate node in the data information base for establishing the LSP by using the address of the intermediate node that is congested according to the parsing, and sets the entry to the congestion flag. When the head node newly establishes an LSP, the Path message sent does not select the intermediate node that is congested, and selects an intermediate node in the information database that is not set with a congestion flag, thereby alleviating the middle while ensuring the LSP service. The purpose of node pressure is to speed up the convergence of LSPs, reduce the interruption time of traffic, and promote the dynamic balance of the network.

 A person skilled in the art can understand that all or part of the steps of implementing the foregoing method embodiments may be implemented by hardware related to program instructions, and the foregoing program may be stored in a computer readable storage medium, and when executed, the program includes The foregoing steps of the method embodiment; and the foregoing storage medium includes: a medium that can store program codes, such as a ROM, a RAM, a magnetic disk, or an optical disk.

 It should be noted that the above embodiments are only for explaining the technical solutions of the present invention, and are not intended to be limiting; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art that: The technical solutions described in the foregoing embodiments are modified, or some of the technical features are equivalently replaced; and the modifications or substitutions do not deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

Rights request  A packet forwarding path LSP network congestion processing method, comprising: a header node receiving a network congestion notification message sent by an intermediate node that is congested; and the header node parsing the received network congestion notification message Obtaining address information of the intermediate node and congestion state information of the intermediate node;  When the head node newly establishes an LSP, the path Path message sent does not pass through the intermediate node.  2. The method according to claim 1, wherein after the obtaining the address information of the intermediate node and the congestion state information of the intermediate node, the method further includes:  The head node finds a data entry corresponding to the intermediate node according to the address information of the intermediate node in the information database for establishing the LSP, and sets a congestion flag of the intermediate node data entry;  Correspondingly, when the head node newly establishes an LSP, the Path message sent does not pass through the intermediate node, and specifically includes:  The head node searches the information database when the LSP is newly established, and when the intermediate node data item is set as a congestion flag, the sent path message does not pass through the intermediate node.  The method of claim 2, after the setting of the congestion flag of the intermediate node data entry, the method further includes: starting a timer, and clearing the congestion flag after the timer expires.  The LSP network congestion processing method according to claim 1, wherein the network node receiving the network congestion notification message sent by the intermediate node that is congested includes:  The header node receives a response path error PathErr message sent by the intermediate node to the Path message sent by the head node, where the PathErr message includes address information of the intermediate node and congestion state information of the intermediate node. The LSP network congestion processing method according to claim 1, wherein the receiving, by the head node, the network congestion notification message sent by the intermediate node that is congested includes: The header node receives a routing message sent by the intermediate node, where the routing message is triggered by a traffic engineering TE interface that changes a management weight metric value in the intermediate node, where the routing message includes a Metric value of the TE interface. And address information of the TE interface, where the metric value indicates congestion state information of the intermediate node.  The LSP network congestion processing method according to claim 5, wherein the metric value is a maximum value OxFFFFFFFF.  A device for processing a MPLS network congestion processing, characterized in that the device includes:  a receiving unit, configured to receive a network congestion notification message sent by an intermediate node that is congested; a parsing unit, configured to parse the network congestion notification message, obtain address information of the intermediate node, and congestion state information of the intermediate node;  The processing unit finds the intermediate node data entry in the information database for establishing the LSP according to the obtained intermediate node address information, and sets a congestion flag of the intermediate node data entry, and sends the The path Path message does not pass through the intermediate node.  A system for label forwarding path LSP network congestion processing, characterized in that the system comprises:  a head node network element device, configured to receive a network congestion notification message sent by an intermediate node that is congested, and parse the received network congestion notification message, obtain address information and congestion state information of the intermediate node, according to the obtained The intermediate node address information finds the intermediate node data entry in the information database for establishing the LSP, and sets the intermediate node data entry to be congested. When the LSP is created, the path Path message sent does not pass. The intermediate node 'ι The intermediate node network element device is configured to detect a self-congestion condition, and send a network congestion notification message to the head node network element device when the intermediate node network element device is congested, where the network congestion notification message includes the intermediate node network Address information of the metadevice and congestion state information of the intermediate node. The LSP network congestion processing system according to claim 8, wherein the network element device comprises a router and a switch.  The LSP network congestion processing system according to claim 8, wherein the head node network element device comprises:  a receiving unit, configured to receive a network congestion notification message sent by an intermediate node that is congested; a parsing unit, configured to parse the network congestion notification message, obtain address information of the intermediate node, and congestion state information of the intermediate node;  The processing unit finds the intermediate node data entry in the information database for establishing the LSP according to the obtained intermediate node address information, and sets a congestion flag of the intermediate node data entry, and sends the The path Path message does not pass through the intermediate node.