KR100606897B1 - Processing method and apparatus for connection establishment - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processing method and apparatus for establishing a connection in a multi-protocol label switching (MPLS) system, particularly in a communication system, and improves the performance of the system in an MPLS system. The present invention relates to a processing method and apparatus for connection establishment that adds flow control to a resource management block of a system so that an overload occurs in the system connection establishment process when an LSP connection establishment is required as a system connection establishment process. .

Multiprotocol Label Switching (MPLS), Connection Settings, Labels, and Transaction IDs

Description

Processing method and apparatus for connection establishment

1 is a diagram for explaining a packet forwarding structure of MPLS.

2 is a block diagram showing an apparatus configuration for establishing a connection of the present invention.

3 is a block diagram showing a detailed configuration of an MPLS resource management block of the present invention.

4 is a flowchart showing a signal type recognition procedure for establishing a connection of the present invention.

5 is a flowchart showing a connection establishment processing procedure of the present invention.

6 is a flowchart illustrating a response processing procedure for a connection establishment request of the present invention.

7 is a flowchart illustrating a processing procedure according to the timer expiration of the present invention.

The present invention relates to a communication system, and more particularly, to a processing method and apparatus for establishing a connection in a multi-protocol label switching (MPLS) system.

In general, a protocol for packet transmission requires a third layer (L3) for routing and a second layer (L2) for switching.

On the contrary, MPLS is a technique of directly switching at high speed by referring to a label in a second layer in transmitting a packet.

The label used in the MPLS is an identifier of short and fixed length, and the third layer switching method of performing packet forwarding using the identifier is MPLS. Herein, the labeled packet is referred to as a label packet.

FIG. 1A is a diagram illustrating a packet forwarding structure of MPLS, and illustrates an example of a label switching path (LSP), which is a path through which label packets are delivered through label switching routers (LSR).

The LSP is usually from one Label Edge Router (hereinafter, abbreviated as LER) to another Label Edge Router.

When a given packet arrives at an ingress LER, the ingress LER first analyzes the packet header, ie, refers to the destination Internet Protocol (hereinafter abbreviated as IP) address included in the header and arrives. The LSP up to the exit LER is set by pushing a predetermined label. At this point, the packet is waiting for transmission. Subsequently, the label packet is forwarded to the LSR through the LSP. The exit LER removes the label from the label packet arriving through the LSP, parses the header, ie delivers the final packet with reference to the destination IP address contained in the header.

As a result, MPLS does not need to interpret the header of the label packet, it simply passes the label packet according to the attached label.

In other words, in the MPLS, the header information, which is the third layer (L3) information, is used only at the inlet LER and the outlet LER. In the LSR, packet forwarding is performed at the second layer according to an attached label.

On the other hand, the core LSR reads the label of each packet, converts the label to a new label, and delivers it to the next node. Where the next node is another LSR or an exit LER. Node means LSR or LER.

Meanwhile, label exchange between nodes on the LSP through which the label packet is delivered enables high-speed packet delivery. MPLS informs the neighboring LSR of the label. This is called label distribution.

For the above label distribution, MPLS has newly created a label distribution protocol (hereinafter referred to as LDP) as a new protocol for delivering label packets.

Meanwhile, in the related art, routing information is collected from nodes (LSRs) from the inlet LER to the outlet LER to pre-assign a node-to-node (LSR and LSR or LSR and LER) label for switching of label packets. In addition, if there is a packet to be transmitted afterwards, the corresponding packet is also transmitted through a predetermined path due to label assignment.

The label assignment and the path setting are performed through signal exchange between the MPLS resource management block and the system call establishment process.

In more detail, the conventional MPLS resource management block assigns a label for a packet once it is required to transmit a predetermined packet. When the label assignment is completed, a connection establishment request signal is sent to the system call process.

However, in the prior art, the system needs to wait for transmission until a response to the connection establishment request is received from the system connection establishment process. As a result, overall system performance is reduced.

In addition, conventionally, if there are many connection setup requests at the same time, overloading occurs easily in the system connection setup process, so that normal operation is difficult. In addition, processing due to abnormal operation is difficult. In particular, overload caused by port failure can cause signal loss. This signal loss causes abnormal behavior.

SUMMARY OF THE INVENTION An object of the present invention is to provide a processing method and apparatus for establishing a connection suitable for improving the performance of the system in the MPLS system.

Another object of the present invention is to add a flow control to the resource management block of the MPLS system for establishing a connection so that an overload does not occur in the system connection establishment process when requesting LSP connection establishment as a system connection establishment process. It is to provide a processing method and apparatus.

A feature of the processing device for connection establishment according to the present invention for achieving the above object comprises: a system connection establishment block for processing connection establishment; The system connection establishment block is configured to include an MPLS resource management block for performing flow control for requesting the connection establishment.

More preferably, the MPLS resource management block, a storage unit for storing the MPLS connection information, and manages a transaction ID (Transaction ID) corresponding to the MPLS connection information used when requesting the connection setup to the system connection configuration block; A transaction table includes a transaction table and a transaction queue that stores MPLS connection information that is not in a state of being assigned the transaction identifier and remains in a standby state. The MPLS connection information includes IP addresses including a destination IP address and a source IP address, and a label corresponding to the IP addresses. The MPLS resource management block allocates a transaction identifier for the MPLS connection information, and stores the allocated transaction identifier in a transaction table.

More preferably, the MPLS resource management block requests the connection establishment from the system connection establishment block, and waits for a predetermined time for a response to the request. If there is no response to the request, the connection establishment request is retried for a predetermined number of times.

In order to achieve the above object, there is provided a processing method for establishing a connection according to the present invention, comprising: receiving a label switching path (LSP) setting request signal and connection information included in the setting request signal; Storing a label, assigning a predetermined transaction identifier to the setup request, and transmitting a setup request of the label switching path (LSP) to a system call process using the transaction identifier. It is to include the step.

More preferably, when the allocation of the transaction identifier for the setup request fails, storing the connection information included in the setup request signal in a queue (Queue). Here, after the connection establishment process by the system connection establishment process is completed, the transaction identifier for the connection information stored in the queue is reassigned, and the request for setting the label switching path (LSP) is set using the reassigned transaction identifier. Send to the system call process.

Also preferably, the method further includes releasing the assigned transaction identifier when receiving an acknowledgment of the establishment request of the label switching path (LSP) from the system connection establishment process.

Other objects, features and advantages of the present invention will become apparent from the detailed description of the embodiments with reference to the accompanying drawings.

Hereinafter, with reference to the accompanying drawings illustrating the configuration and operation of the embodiment of the present invention, the configuration and operation of the present invention shown in the drawings and described by it will be described by at least one embodiment, By the technical spirit of the present invention described above and its core configuration and operation is not limited.

2 is a block diagram showing an apparatus configuration for establishing a connection of the present invention.

Referring to FIG. 2, the apparatus of the present invention is composed of an LDP block 10, an MPLS resource management block 20, and a system connection establishment block 30. The system connection establishment block 30 is a system call establishment process.

 The core of the configuration of the present invention is the MPLS resource management block 20, MPLS resource management block 20 receives the LSP connection establishment request from the LDP block 10 to request the LSP connection establishment to the system connection establishment block 30 do.

In particular, when the MPLS resource management block 20 requests LSP connection establishment, the MPLS resource management block 20 allocates a transaction identifier for MPLS connection information (IP address, label, etc.), and stores the allocated transaction identifier.

The MPLS resource management block 20 requests the system connection establishment block 30 to establish the connection, and the MPLS resource management block 20 includes a timer for responding to the connection establishment request for a predetermined time determined by the timer. waiting.

In addition, when there is no response from the system connection establishment block 30 to the connection establishment request, the MPLS resource management block 20 further attempts a connection establishment request to the system connection establishment block 30 for a predetermined number of times.

Meanwhile, the system connection establishment block 30 processes the connection establishment required by the MPLS resource management block 20.

In particular, the MPLS resource management block 20 requests flow connection at a speed that can be processed by the system connection establishment block 30 by performing flow control such as the connection establishment request shown in FIGS. 4 to 7.

3 is a block diagram showing the detailed configuration of the MPLS resource management block of the present invention.

Referring to FIG. 3, the MPLS resource management block includes a storage 100, a transaction table 110, and a transaction queue 120.

The storage unit 100 stores MPLS connection information. Here, each MPLS connection information is an IP address and a label corresponding to the IP address. IP addresses include the destination IP address and the source IP address. However, in the present invention, since the MPLS resource management block assigns a label, the storage unit 100 stores the IP address (destination IP address and source IP address) provided when the LSP connection establishment request is made. After assigning a label corresponding to the IP address, it is desirable to further store the label along with the IP address.

The transaction table 110 manages a transaction ID used when a connection establishment request is made to the system connection establishment process. The transaction identifier corresponds to each connection information stored in the storage unit 100. That is, as one example, one connection information corresponds to one transaction identifier.

The transaction queue 120 stores the MPLS connection information that exists in the idle state because it is not assigned a transaction identifier. In more detail, the transaction queue 120 stores MPLS connection information for a packet in a waiting state that has not been assigned a transaction identifier. Here, the transaction queue 120 stores at least one of an IP address and a label as MPLS connection information.

Hereinafter, flow control in the MPLS resource management block will be described in more detail below.

4 is a flowchart illustrating a signal type recognition procedure for establishing a connection according to the present invention.

Referring to FIG. 4, the MPLS resource management block receives a predetermined signal from another block or process (S10).

The MPLS resource management block determines the type of the received signal (S11).

If it is determined that the received signal is a connection establishment request signal, the MPLS resource management block performs the connection establishment procedure shown in FIG. 5 (S12).

If it is determined that the received signal is a connection establishment response signal, the MPLS resource management block performs a response processing procedure for the connection establishment request shown in FIG. 6 (S13).

Meanwhile, if the MPLS resource management block does not receive the connection establishment response signal before the timer expires after transmitting the connection establishment request signal to the system connection establishment process, the MPLS resource management block performs the processing procedure according to the timer expiration shown in FIG. 7 accordingly. S14).

5 is a flowchart showing a connection establishment processing procedure of the present invention.

Referring to FIG. 5, when the MPLS resource management block receives an LSP connection establishment request signal, primary resources for MPLS connection information (IP address) provided due to the LSP connection establishment request are allocated (S20). The resource for the MPLS connection information is a label and stores the MPLS connection information (IP address) provided due to the LSP connection establishment request.

If the label allocation for the LSP connection establishment request fails, the MPLS resource management block transmits a response signal indicating the failure of the LSP connection establishment to the LDP block (S23).

On the other hand, if the label allocation for the LSP connection establishment request is successful, the MPLS resource management block allocates a transaction identifier for the assigned label (S21). And store the assigned transaction identifier.

If the allocation of the transaction identifier fails, the MPLS resource management block stores the connection information that failed to allocate the transaction in the transaction queue. For example, the MPLS resource management block stores a label previously allocated according to the LSP connection establishment request and / or connection information corresponding to the label in a transaction queue (S24).

On the other hand, if the transaction identifier is successfully assigned, the connection establishment request signal is transmitted to the system connection establishment process using the assigned transaction identifier (S22). It then starts a timer to apply for waiting for a response from the system connection establishment process.

6 is a flowchart illustrating a response processing procedure for a connection establishment request according to the present invention.

Referring to FIG. 6, when the MPLS resource management block receives a positive response signal from the system connection establishment process with respect to the LSP connection establishment request, the MPLS resource management block releases the corresponding transaction identifier and releases the timer that was simultaneously started (S30). .

If the MPLS resource management block succeeds in establishing the LSP connection, the MPLS resource management block transmits an acknowledgment signal indicating the successful connection establishment to the LDP block (S31, 32).

However, if the LSP connection establishment fails, the MPLS resource management block transmits a negative response signal indicating the connection establishment failure to the LDP block (S33).

After the success or failure of the current LSP connection establishment as described above, that is, after the connection establishment process by the current system connection establishment process is completed, the MPLS resource management block checks whether data stored in the transaction queue exists (S34). . That is, the MPLS resource management block checks whether there is pending connection information in the transaction queue that has not been assigned a transaction identifier.

If there is no data stored in the transaction queue, the MPLS resource management block is waiting for the next connection establishment request. In other words, the MPLS resource management block waits for another connection establishment request.

However, if there is data stored in the transaction queue, the MPLS resource management block reallocates the transaction identifier for the connection information stored in the transaction queue. And store the assigned transaction identifier.

If the allocation of the transaction identifier fails, the MPLS resource management block stores the connection information that failed to allocate the transaction in the transaction queue. For example, the MPLS resource management block stores the previously allocated label and / or connection information corresponding to the label in the transaction queue according to the LSP connection establishment request (S37).

On the other hand, if the transaction identifier is successfully allocated, the connection establishment request signal is transmitted to the system connection establishment process using the assigned transaction identifier (S35, 36). It then starts a timer to apply for waiting for a response from the system connection establishment process.

7 is a flowchart showing a processing procedure according to the timer expiration of the present invention.

Referring to FIG. 7, when there is no response to the connection establishment request from the system connection establishment process, the MPLS resource management block further attempts a connection establishment request to the system connection establishment process by a predetermined number of times.

Accordingly, the MPLS resource management block checks whether the number of times of resending the connection establishment request signal to the current system connection establishment process exceeds a predetermined threshold retransmission number (S40).

If the current number of retransmissions exceeds the threshold number of retransmissions, the MPLS resource management block transmits a response signal notifying the failure of the LSP connection establishment to the LSP block (S42).

On the other hand, if the current retransmission count does not exceed the threshold retransmission count, the MPLS resource management block transmits a connection establishment request signal to the system connection establishment process by using the same transaction identifier previously assigned (S41). It then starts a timer to apply for waiting for a response from the system connection establishment process.

After the current retransmission count exceeds the critical retransmission count as described above, the MPLS resource management block checks whether there is data stored in the transaction queue (S43). That is, the MPLS resource management block checks whether there is pending connection information in the transaction queue that has not been assigned a transaction identifier.

If there is no data stored in the transaction queue, the MPLS resource management block is waiting for the next connection establishment request. In other words, the MPLS resource management block waits for another connection establishment request.

However, if there is data stored in the transaction queue, the MPLS resource management block reassigns the transaction identifier for the connection information stored in the transaction queue. And store the assigned transaction identifier.

If the allocation of the transaction identifier fails, the MPLS resource management block stores the connection information that failed to allocate the transaction in the transaction queue. For example, the MPLS resource management block stores a previously allocated label and / or connection information corresponding to the label in the transaction queue according to the LSP connection establishment request (S46).

On the other hand, if the transaction identifier is successfully allocated, the connection establishment request signal is transmitted to the system connection establishment process using the assigned transaction identifier (S44, 45). It then starts a timer to apply for waiting for a response from the system connection establishment process.

As described above, according to the present invention, an overload of the system connection establishment process can be reduced even when many connection establishment requests or connection release processing requests occur simultaneously.

In addition, there is no need to wait for packets to be sent, so there is no overall system degradation.

In particular, it resolves abnormal behavior caused by signal loss due to port failure.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

Claims (10)

A system connection establishment block for processing a connection establishment; And an MPLS resource management block configured to perform a flow control for requesting the connection establishment in the system connection establishment block. The method of claim 1, wherein the MPLS resource management block, A storage unit storing MPLS connection information; A transaction table for managing a transaction ID corresponding to the MPLS connection information used for requesting connection establishment with the system connection establishment block; And a transaction queue configured to store MPLS connection information which is in a waiting state because the transaction identifier is not allocated. 3. The processing apparatus of claim 2, wherein the MPLS connection information comprises IP addresses including a destination IP address and a source IP address, and a label corresponding to the IP addresses. . The method of claim 2, wherein the MPLS resource management block, And assigning a transaction identifier for the MPLS connection information, and storing the assigned transaction identifier in a transaction table. The method of claim 1, wherein the MPLS resource management block, Requesting the connection establishment from the system connection establishment block, and waiting for a response to the request for a predetermined time. The method of claim 1, wherein the MPLS resource management block requests the connection establishment from the system connection establishment block, and retries the connection establishment request for a predetermined number of times when there is no response to the request. Processing device for connection establishment. Receiving a label switching path (LSP) establishment request signal; Storing the connection information included in the setup request signal; Allocating a predetermined transaction identifier to the setup request; And sending a setup request for the label switching path (LSP) to a system call process using the transaction identifier. The method of claim 7, further comprising storing connection information included in the setup request signal in a queue when the transaction identifier for the setup request fails. Treatment method. 9. The method of claim 8, wherein after the connection establishment process by the system connection establishment process is completed, the transaction identifier for the connection information stored in the queue is reassigned, and the label switching path (LSP) is used by using the reassigned transaction identifier. Transmitting a setup request to the system call process. 8. The method of claim 7, further comprising releasing the assigned transaction identifier upon receiving an acknowledgment of the establishment request of the label switching path (LSP) from the system connection establishment process. Action to set up.

Images