KR100950152B1 - Signaling method for O-UNI - Google Patents

Abstract

The present invention discloses an optical user network interface (O-UNI) signaling method for converting an optical virtual private network (O-VPN) connection configuration.

The O-UNI signaling method of the present invention finds and releases the largest number of connections that do not separate the current O-VPN even if they are released from among the connections to be released, and the current optical transport network situation and the client system among the connections to be created. In order to find and create the largest number of connections that can be created in consideration of the current port status, connection configuration conversion can be performed without temporary separation of O-VPN.

Description

Optical user network interface signaling method for changing the configuration of the optical virtual private network connection setting {Signaling method for O-UNI}

1 is a diagram showing a configuration relationship between a conventional optical transport network and a client system.

2 illustrates an embodiment of an O-VPN connection setup configuration.

3 is a diagram showing a configuration of an objective O-VPN for which connection settings are to be converted.

4 is a view illustrating a state in which O-VPN is separated during a connection setting conversion process;

5 is a view showing a connection state of the process of converting O-VPN connection settings according to the present invention.

6 is a flowchart illustrating a connection setting conversion process according to the present invention.

The present invention relates to a signaling method of an optical-user network interface (O-UNI), and more particularly, to a connection configuration configuration of an optical-virtual private network (O-VPN) from a client. The present invention relates to an O-UNI signaling method that allows a configuration change to be made as quickly as possible without temporarily disconnecting the client network when a change request is requested.

Intelligent optical transport networks are realized with the introduction of Optical Cross Connect (OXC) with an intelligent control plane in the structure of an existing optical transport network consisting of a set of point-to-point transmission links.

The optical transport network operates in a server / client relationship with external client networks. In other words, the detailed information inside the optical transport network is hidden from the client and works with the client according to a well-defined service interface. O-UNI is an international standard in the field of signal transmission established by the Optical Internetworking Forum (OIF). O-UNI 1.0 is now completed, and it corresponds to the service interface specification between the optical transport network and the client network. Many OXC system manufacturers now implement O-UNI 1.0.

O-VPN is a new concept of VPN service provided to clients as intelligent optical transport network is realized. While O-VPN service provides a large number of static connections between two client systems, Provides interconnection between client systems. And, when a change in interconnect configuration is given from the client, it accepts it in real time.

1 is a diagram illustrating a configuration relationship between a conventional optical transmission network and a client system.

The optical transport network 1 is composed of multiple OXC systems 2 and a transmission link based on Wavelength Division Multiplex (WDM) or Synchronous Digital Hierarchy (SDH).                         

The client system 3 receiving the connection service of the optical transport network may be various various service networks, and interwork with the optical transport network 1 through the O-UNI signaling interface 4. The client systems 3 are interconnected via a connection 5 provided by the optical transport network 1. Links of optical transport networks interconnecting a single client system 3 are assembled to form one O-VPN.

FIG. 2 is a diagram illustrating an embodiment of an O-VPN connection establishment configuration, in which client systems 3 are connected to each other to form an O-VPN network.

In such O-VPN service, the connection between client systems can be changed from time to time, and the optical network operator must be able to quickly accommodate the request for change of the legitimate connection setting of the client.

The connection configuration change request of the O-VPN is converted into a plurality of O-UNI signaling messages and given to the optical transport network. That is, the change from the current O-VPN connection establishment structure to the new O-VPN connection establishment structure is made by sequentially canceling and creating new connections. Termination and new creation of these individual connections is the most basic function that O-UNI signaling provides. The connection generation and termination function of O-UNI signaling is implemented in conjunction with the control plane in the optical transmission network implemented in a distributed form.

Thus, even if the O-UNI signaling request for the creation and termination of individual connections is given all at once, it is not a problem in terms of the optical transport network.

However, O-VPN, that is, a client network, may cause a situation in which the traffic flow is temporarily blocked because part of the entire network is disconnected while the existing O-VPN connection structure is changed to a new connection structure.

3 illustrates the configuration of the O-VPN for the purpose when the O-VPN connection structure of FIG. 2 needs to be changed due to a change in traffic flow of a client network.

2 and 3, except for one of the connections 13 of FIG. 2, all other connections 11, 12, 14-16 have to be released and new connections 21-25 are made. Should be set. When deciding to terminate and create each connection to configure O-VPN, make sure that the client network is not separated at any point during the conversion, and that as many O-UNI signalings as possible can be run simultaneously to minimize the conversion time. You should be able to. However, as shown in FIG. 4, when the connections 14 and 15 are released to form the target O-VPN, the O-VPN is temporarily separated and the flow of traffic is physically blocked.

Accordingly, an object of the present invention for solving the above-described problem is to determine the order of O-UNI signaling so that disconnection between client systems does not occur during connection configuration conversion.

The O-UNI signaling method of the present invention for achieving the above object comprises a first step of selecting connections to be released and connections to be created; A second step of finding and releasing connections among the connections to be released, which do not separate the current O-VPN even if released; A third step of finding and creating currently available connections among the connections to be created; And a fourth step of repeating the second and third steps until there are no connections to be released and no connections to be created.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

5 is a view showing a connection state of the process of converting the O-VPN connection configuration according to the present invention, Figure 6 is a flow chart illustrating such a connection configuration conversion process.

First, the set A of the connections 11 to 16 constituting the current O-VPN and the object O to be converted by receiving the current O-VPN connection configuration shape and the object O-VPN connection configuration shape. Obtain a set B of connections 13, 21-25 forming the VPN (step 601).

Next, using the set of connections A and B, two sets of differences (C = A-B, D = B-A) are obtained (step 602). That is, it configures a set (C) of connections to be released and a set (D) of newly created connections to form the target O-VPN.

If the sets C and D are constructed, it is checked whether these two sets C and D are empty (step 603). At this time, if the difference set (C, D) is the empty set, the current O-VPN and the target O-VPN are the same, so the connection setting conversion is not necessary or the connection setting conversion is completed, and thus the conversion procedure is terminated.

However, in the case where the difference sets C and D are not empty, first, among the connections 11, 12, 14 to 16 belonging to the difference set C, even if the connection is released, the current O-VPN is not separated. Construct a set C '(step 604).                     

That is, the set C 'becomes a subset of the set C, and in the embodiment of FIG. 5A, it is assumed that the connections 12 and 14 belong to this set C'. At this time, a plurality of such sets C 'may exist (for example, a set of connections 11 and 15 may be possible), but a set having the most connections among them or one of such sets is configured as a set C'. do.

When the connections 12 and 14 belonging to the set C 'are determined, as shown in FIG. 5B, the disconnection O-UNI procedure is performed on the corresponding connections 12 and 14, and then the set ( Delete the connections 12, 14 belonging to C ') (step 605).

And, among the connections 21 to 25 belonging to the set D, the largest number of new connections that can be newly created are found according to the current resource situation of the optical transport network 1 and the port situation of the client system 3. (Step 606).

That is, the set D 'becomes a subset of the set D, and in the present embodiment, it is assumed that the connections 21 and 22 are the connections belonging to the subset D'.

Next, the O-UNI connection creation procedure is performed on the connections 21 and 22 belonging to the set D 'as shown in FIG. 5B, and the successfully created connections are deleted from the set D (step 607). ).

Then, in step 604 described above, the process of step 607 is repeated until there are no more connections in the sets C and D.

That is, even if the connections 11 and 16 are released among the connections 11, 15 and 16 of the set C by the newly created connections 21 and 22, the current O-VPN is not separated. , 16), and delete them from the set C (steps 604 and 605). Next, after creating the connections 23 and 24, O-VPNs having a connection as shown in FIG. 5C are formed by deleting the connections 23 and 24 from the set D (steps 606 and 607).

Since there are still connections belonging to the set (C, D), the purpose of having the connection relationship as shown in FIG. 5D by performing the steps 604 to 607 again in the same manner, releasing the connection 15 and creating the connection 25 O-VPN is formed.

As described above, the O-UNI signaling method of the present invention is based on the current optical transport network situation and client system among the most connections that do not separate the current O-VPN among the total connections to be released and connections to be created. By selecting the largest number of connections that can be created in consideration of the port status and performing O-UNI connection release and creation, O-VPN connection configuration conversion can be performed in a minimum time without temporary disconnection of the client system.

Claims (4)

In the optical user network interface (O-UNI) signaling for converting a connection between a plurality of client systems in accordance with a connection setup conversion request in an optical virtual private network (O-VPN), A first step of selecting connections to be released and connections to be created; A second step of locating and releasing connections among the connections to be released that do not separate the current O-VPN even when released; A third step of finding and creating currently available connections among the connections to be created; And And a fourth step of repeating the second step and the third step until there are no connections to be released and no connections to be created. The method of claim 1 wherein the second step is 10. A method for signaling an optical user network interface comprising configuring sets with connections that do not currently separate O-VPNs and then disconnecting the set with the most connections of the sets or any of the sets. The method of claim 1, wherein the third step Optical user network interface signaling characterized by constructing sets having connections to be newly created in consideration of the current optical transport network situation and port status of the client system, and generating the connections of the set having the most connections among the sets. Way. The method of claim 2 or 3, wherein the fourth step The connections released in the second step and the connections created in the third step are deleted from the connections to be released and the connections to be created, respectively, until there are no connections to be released and connections to be created. Optical user network interface signaling method.

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