KR100440580B1 - A Proxy Signaling Service Method in ATM Switching System - Google Patents

Abstract

In the method for processing proxy signaling in an ATM switching system, a proxy signaling agent on a UNI having a different physical link in an ATM switching system controls a connection between a user terminal having a different physical interface and a switching system. The present invention relates to a proxy signaling processing method of an ATM switching system that substitutes a signaling function in a user terminal having one signaling function on a user terminal having no SVC signaling function on an interface. To this end, the present invention is a proxy signaling processing method in an ATM switching system in which a plurality of user terminals are connected to different physical links, the method comprising: generating a proxy logical port of a user terminal that is a target of a proxy signaling service in the switching system; Stage 1; A second step of creating a signaling channel by generating a proxy signaling agent in the generated proxy logical port; And receiving a proxy signaling call establishment request of the user terminal through the generated signaling channel of the proxy signaling agent, and providing a connection identifier to the switching system according to the request of the proxy signaling agent.

Description

Proxy signaling method in asynchronous transfer mode switching system {A Proxy Signaling Service Method in ATM Switching System}

The present invention relates to a proxy signaling processing method of an ATM switching system. More particularly, the present invention relates to a method for processing a proxy signaling of an ATM switching system, and more particularly, on a user network interface having a different physical link of an asynchronous transmission mode (hereinafter referred to as ATM). The present invention relates to a proxy signaling processing method of an ATM switching system for controlling a connection between a user terminal having a different physical interface and a switching system, and a computer-readable recording medium having recorded thereon a program for executing the same. .

In general, the ATM switching system has a function of transferring information to each other through a connection to another subscriber station desired by the subscriber station through a connection with a subscriber station or another switching system. In particular, the open ATM switching system accommodates interfaces having a hierarchy of STM-4, STM-1, DS-3, DS-1, etc. of the switch through the GSMP protocol, respectively, UNI or NNI (Network-Network Interface; Cell of ATM layer of NNI). In the case of accommodating the subscriber station, a simple communication terminal may provide a permanent virtual connection (hereinafter referred to as PVC) service, and a terminal having a UNI protocol function may be switched to a PVC service as well as a switched virtual connection. Connection (hereinafter referred to as SVC) service is available. At this time, when the subscriber station is directly connected to the switching system, it is basically possible to connect one physical link to one physical link, and the subscriber number is assigned to the corresponding interface to distinguish the subscribers.

ATM switching system has the biggest feature that it can provide various kinds of services through virtual connection. This is possible because of the virtual connection (hereinafter referred to as VC). In ATM, virtual connection is possible through VPI and VCI. Therefore, the ATM service can be represented by multiple connections on one physical link regardless of the required bandwidth.

On the other hand, in the ATM switching system, it should generally be able to accommodate various kinds of subscribers, and each subscriber station should have an ATM matching function. In particular, the SVC function must have a function to process UNI protocols defined by standardization organizations such as ITU-T or ATM FORUM. The protocol function consists of a message stack and information elements specified by the protocol, operating on a finite state machine with a protocol stack according to the recommendations. In order for these protocol messages to be communicated with each other, a separate channel must be promised between the subscriber station and the switching system. If there is no restriction in the separate channel, the channel is processed by setting the channel with VPI of 0 and VCI of 5 in the corresponding physical link. Such a channel is called a signaling channel among control channels, and a function for synchronizing the channel and matching the ATM adaptation layer (AAL) prior to the delivery of such a message is called SAAL. After the SAAL is activated, information is exchanged through the aforementioned channel. That is, through this, the type of service desired by the subscriber, the address of the other party's subscriber station, and QoS information are encapsulated in a message in the form of an information element and delivered.

In general, in the UNI interface, signaling functions have meaning within a single physical link, and virtual connections are classified by VPI and VCI values. In order to distinguish multiple subscribers on one physical link, signaling service is performed by dividing subscribers by VPI and using VPCI as a signaling key.

Conventionally, when one or more user terminals are connected by an independent link with the ATM switching system, since the SVC service on the UNI has a meaning on one physical link, the connection control function must be performed through a separate signaling channel for each physical link requiring the SVC function. Could be done. Therefore, the user terminal that does not have the SVC signaling function on the UNI had to set a separate signaling channel for connection control with the switching system. In addition, in the conventional UNI interface, the SVC function has a meaning only in a physical link or a VPI in a physical link in which a signaling channel is set, and a connection control function has to be performed through a separate signaling channel for each physical link requiring an SVC function.

In order to solve the above problems, the present invention provides an ATM through a connection control between a user terminal having a different physical interface and a switching system on a UNI interface having different physical links in an open ATM switching system. An object of the present invention is to provide a proxy signaling processing method of an open ATM switching system that provides a connection service.

1 is a structural diagram according to an embodiment of an ATM switching system to which the present invention is applied.

2 is a relation structure diagram of a proxy logical port according to the present invention.

3 is a configuration diagram of proxy signaling to which the present invention is applied.

4 is a flowchart of generating a proxy logical port according to the present invention.

5 is a flowchart for generating a proxy signaling agent according to the present invention.

6 is a flowchart of a proxy signaling service according to the present invention.

Explanation of symbols on the main parts of the drawings

30: ATM call control unit (ACC) 40: ATM interface module

31: User Network Interface Protocol Control Function Block (UNPCF)

32: user network interface call control function block (UNCCF)

50: workstation module (WSM) 60: switch fabric module (SFM)

331: proxy signaling agent (PSA) 333: switching system

In accordance with an aspect of the present invention, there is provided a proxy signaling method in an ATM switching system in which a plurality of user terminals are connected to different physical links, wherein the proxy logical port of a user terminal that is a target of a proxy signaling service in the switching system. Generating a first step; A second step of creating a signaling channel by generating a proxy signaling agent in the generated proxy logical port; And receiving a proxy signaling call establishment request of the user terminal through the generated signaling channel of the proxy signaling agent, and providing a connection identifier to the switching system according to the request of the proxy signaling agent.

In addition, the present invention to achieve the above object, the computer, a first function for generating a proxy logical port of the user terminal to be the target of the proxy signaling service in the switching system; A second function of creating a signaling channel by generating a proxy signaling agent in the generated proxy logical port; And a program for executing a third function of providing a connection identifier to the switching system according to a request of the proxy signaling agent when receiving a proxy signaling call establishment request of the user terminal through the generated signaling channel of the proxy signaling agent. Provide a computer-readable recording medium for recording.

According to the present invention, a plurality of physical UNI links are designated as one logical group, and then all terminals in the group are efficiently provided by a user or an exchange system by using a terminal that performs one SVC function. To this end, in the present invention, the ATM switching system defines a proxy port for identifying user terminals on different physical links, processes them as one subscriber number, and designates a proxy agent for virtual connection of one or more proxy ports. Set. In addition, by using the proxy port information configured when the actual proxy signaling agent requests a service, the proxy port is classified by a desired connection identifier, and a virtual connection control function is processed according to the VPI value defined in the port.

In the ATM switching system, the SVC service on the UNI interface means providing the desired service in the network at the time desired by the user in the physical link, and defines the meaning in the protocol. The protocol is negotiated through the above-mentioned standardization organization. Basically, ITU-T's DSS2 signaling standard and ATM-Forum's UNI3.0, UNI3.1, and UNI4.0 are typical examples. Such signaling is delivered through a defined signaling channel. For this purpose, the signaling channel should be set up and synchronized with the terminal in advance. In general, one signaling channel is configured on one physical link. In this case, messages are exchanged using VPI of 0 and VCI of 5. However, in order to receive the virtual connection service without setting up the signaling channel, a separate signaling agent is designated and a separate procedure between the signaling agent, the user terminal, and the switching system is required.

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

1 is a structural diagram according to an embodiment of an ATM switching system to which the present invention is applied, and schematically illustrates a configuration diagram and a module of an ATM switching system. Referring to FIG. 1, an access multiplex module (AMM) 10, a media gateway module (MGM) 20, and an ATM interface module 40 (AIM) are external interface modules, that is, interface modules for UNI or NNI. Switch Fabric Module (SFM) 60 represents a switch module, and WorkStation Module (WSM) 50 is a workstation module for operator matching or operation maintenance functions. Multi-subscriber processing according to the present invention is done in ACC (ATM Call Controller) 30. The ACC 30 is a basic processor for call control of an exchange system, and a plurality of application blocks perform respective functions. Among them, Logical Port Control Function (LPCF) 33 performs logical port management function according to the configuration, operator matching, status and configuration of the logical port for multi-subscriber management according to the present invention. Functions such as creating and deleting ports. UNPCF (User Network Interface Protocol Control Function) 31 and UNCCF (User Network Interface Call Control Function) 32 are blocks for the UNI SVC function of the multi subscriber or the general subscriber according to the present invention, and the UNPCF 31 is a protocol. The UNCCF 32 provides a function for controlling a service provided by the switching system for the connection required by the subscriber.

FIG. 2 is a structural diagram of a relation of a proxy logical port according to the present invention, and shows a structure of a logical port and a relation in the ATM switching system shown in FIG. 2 (a) is a configuration of a logical port number and may also be a key of the R_LPORT_INF relation. The logical port number should have physical shape information 221 as a basis, which can be changed depending on the switch device. However, other connection control functions do not need to know what the physical shape means. The ATM information divided by the general switch control protocol indicates which specific control system manages the corresponding GSMP port on one switch. The logical port also needs such control system information, which is referred to as master 222. Multiple logical ports can be created on one master, which can be up to a virtual path. In order to display this, the configuration of the logical port has a unique number of its own port, which is indicated by the logical port separator 223.

The configuration of R_LPORT_INF, which is a logical port relation using the logical port number as the key 224, is shown in Fig. 2B. First, the VPI range 225, VCI range 226, forward bandwidth 227 and reverse bandwidth 228 of the logical port represent the basic ATM link resources of the logical port. Link type 229 indicates one of UNI and NNI. This refers to the cell type in the ATM layer of the ATM system. UNI and NNI are different in cell format. As in the present invention, the UNI protocol corresponds to the case where the link type is UNI. The logical port type 230 is classified into three types, which are independent of a physical link type when a logical port is mapped one-to-one with a physical link, and only a logical VPC type / VPI that guarantees independent bandwidth for each VPI on the physical link. It is divided into the VPI Associate type, and finally divided into a group type for serving one or more physical links according to the present invention through a proxy agent. To this end, it is possible to set and release the proxy port by the operator command, which will be described in detail with reference to FIG. 4 below.

The logical port state 231 represents the state of the port and is divided into three types: normal, down, and block. First, Normal indicates that the corresponding port is available for service, and Down indicates that the port is not ready because it is not ready or otherwise abnormal. In addition, Block indicates a case in which the port is restricted by normal or abnormal status according to an operator's request. The logical port group 232 is a case where the logical port type 230 described above is a group type, and represents a group number when the logical port group 230 is a group type. If it is designated as a proxy port, it has proxy group information and stores it in logical port information. 1 if not a group port.

VPI port 233 represents the original logical port to which the VPI port corresponds. That is, when multiple VPI ports are created in a logical link of a certain physical link type, the original logical port is represented in each VPI port so that the relationship between the VPI ports in one link can be known in the multi-subscriber service. The protocol 234 means a specific protocol used for the corresponding logical port for the SVC service, and in the case of UNI, protocols such as DSS2, UNI3.1, and UNI4.0 may be assigned. The proxy signaling agent is designated through protocol assignment. Hereinafter, a procedure of registering a proxy signaling server will be described in detail with reference to FIG. 5.

The virtual UNI 235 is a virtual UNI number assigned for a virtual UNI service, and is used to distinguish when multiple VPI ports have the same VPCI in one physical link port. The VPCI number 236 can be distinguished through signaling as a number assigned to designate a proxy logical port and classify the designated port together with the above group number according to an embodiment of the present invention. This will be described in detail with reference to FIG. 3. The use of ILMI 237 indicates whether the port accepts ILMI functionality and the AW value 238 and Agg_Token 239 indicate the attributes of the link when using the PNNI protocol. The service availability rate 240 refers to a ratio of the utilization range of the bandwidth of the logical port according to the operator's request, which means that 100% is used.

3 is a conceptual diagram according to an embodiment of proxy signaling according to the present invention. In FIG. 3, a PSA (Proxy Signaling Agent) 331 represents a proxy signaling agent and represents a state in which a signaling channel is connected to a switching system. Terminals A, B, and C 332 are ATM terminals each having no ATM signaling function, and are connected to a switching system and connected with a specific VPI. Since the A, B, and C terminals 332 do not have a signaling function, connection of the switching system and the signaling channel is unnecessary, and only one or more VP paths are connected in advance in designing a network. 3, each terminal has a VP path having VPI 0. For example, if each terminal 332 is connected to the switching system by STM-1, each VP path has a bandwidth of 155 Mbps, and if it needs to have another VP path, 155 Mbps is divided (different). You just need to At this time, of course, it must have a unique value of VPCI.

Hereinafter, a process of performing an actual service of proxy signaling according to the present invention will be described with reference to FIG. 3. The PSA 331 knows in advance that a signaling function will be performed on behalf of the A, B, and C terminals 332. If UE A wants to make an SVC connection service and transmits a SETUP message through a signaling channel connected to the switching system 333, the VPCI transmits the value of 1 to the network by setting the connection identifier as Explicit VPCI. The network determines that it is a proxy service and finds an interface corresponding to the corresponding VPCI. If it finds the interface connected with terminal A, it finds the VPI defined in the interface and if there is a desired VCI, assigns it to one of the VCIs in the corresponding VPI, and assigns it to the PSA 331 through a CALL PROC or ALERT or CONNECT message. Notify the results.

Looking at the case of the incoming service, as described above, the A, B, C terminals 332 share the same subscriber number, so if the service is requested to the corresponding subscriber number in the switching system 333 the PSA 331 You will be asked to send a SETUP message and assign a connection identifier. In this case, the exchange system 333 generally uses a connection identifier assigned by the PSA 331 without transmitting connection identifier information. However, if the bandwidth of the required service corresponds to a specific link only, The call setup may be requested by inserting the VPCI of the interface.

4 is a flowchart for generating a proxy logical port for a proxy signaling service function according to the present invention. A process of generating a proxy logical port will be described with reference to FIG. 4. The operator may create one or more proxy logical ports in the logical port of the physical link type that has already been created, and the WSM 50 accepts the proxy port generation request of the operator (S401). Information input at this time is a logical port, VPI, VPCI, forward bandwidth, reverse bandwidth, and proxy group number of the existing physical link type. The LPCF 33 of the ACC 30 checks the logical port information of the physical link type input according to the request for generating the proxy logical port in R_LPORT_INF (S402). When it is confirmed that the logical port exists and the logical port is a physical link type, the range of the input VPI is checked (S403). Next, a proxy group number defined by the switching system is designated for the proxy signaling service (S404). The proxy group number may be designated by an operator or may be arbitrarily designated by a logical port manager. Then, the bandwidth is checked (S403). If the bandwidth is given, it is necessary to guarantee or limit the service band of the subscriber associated with a specific VPI in the network. In this case, the bandwidth is changed due to the subtraction of the forward and reverse bands from the current remaining bandwidth of the corresponding physical link. If the bandwidth is not given, only the VPI is promised, and the subscriber station does not need to limit the band, but is free to use it or is used when the bandwidth is already limited in the subscriber station. After the above confirmation, the proxy logical port is generated and added to the R_LPORT_INF (S406). At this time, the logical port number is composed of 4 bytes as described in FIG. 2, and when the VPI uses a single input VPI and the band is specified as described above, the specified value is entered and specified. If not, the value of the logical port of the physical link type is input as it is. In addition, the logical port type is a group type, and the VPCI stores the stored content and the new proxy logical port to the operator using the input number (S407).

5 is a flowchart for generating a proxy signaling agent according to the present invention. The agent generation process will be described with reference to FIG. 5. The proxy signaling agent according to the present invention may be one of the proxy logical ports generated as described in FIG. 4 or may be a logical port of a physical link type. First, the operator requests to generate a proxy signaling agent (S501). At this time, the inputted information is the logical port number and the proxy group number. Subsequently, the LPCF 33 of the ACC 30 checks whether an input logical port exists and checks whether a protocol is currently registered (S502). If there is no logical port or the protocol is already registered (S503), the execution stops and outputs it to the operator (S507). If not (S504), the proxy group number is checked (S504). The proxy group number must input the group numbers of the generated proxy logical ports. If the group number does not exist, the generation fails. When the proxy group number matches the generated group numbers of the logical logical ports, if a UNI port registration request is made to the UNCCF 32 block among the UNPCF 31 and UNCCF 32 blocks that perform the UNI SVC function (S505). ), The UNCCF 32 requests this to the UNPCF 31 and registers a signaling channel to the corresponding logical port and notifies the LPCF 33 of the registration result of the signaling channel (S506). Subsequently, the result is output to the operator (S507). After the generation of the proxy signaling agent as described above, the preparation of the proxy signaling service is completed.

6 is a flowchart of a proxy signaling service according to the present invention. Proxy signaling service in the UNI is started by sending a SETUP message from the subscriber station. Of course, the message starts with the preparation of the proxy signaling agent described above ready. Referring to FIG. 6, the UNPCF 31 block of the ACC 30 transmits a SETUP message to the UNCCF 32 (S601). Upon receiving the SETUP message, the UNCCF 32 checks whether the current service is a proxy signaling service agent (S602). That is, it is checked whether or not a signaling channel registered as the generated proxy signaling agent described above has come through. If the proxy signaling service, the SETUP message received at this time is analyzed to check whether there is a problem with the message or other information elements constituting the message (S603). If there is no abnormality as a result of the check, the connection identifier information is analyzed from the SETUP message and the corresponding connection identifier is allocated (S604). At this time, the connection identifier may or may not selectively enter the SETUP message. If included in the SETUP message it is processed differently according to the meaning of the connection identifier information element (S605). In this case, there may be a VP-associate request, an Explicit VPCI request, and a No indication (no indication) for the VCC (Virtual Channel Connection) when the connection identifier is included in the SETUP message. have. First, the VP-associate request is a connection request by allocating a VCI in a VPI set to a signaling channel of a corresponding proxy signaling agent. In this case, no separate information is required. Since the network already knows the signaling channel VPI of the proxy signaling agent, the VCI is allocated within the corresponding VPI (S606). In the case of explicit VPCI, the VPCI in the transmitted message is allocated (S607), and the VCI in the corresponding VPI value is allocated according to the previously assigned VPCI value (S608). That is, first, the VPCI value that has been explicitly transmitted in the SETUP message is extracted. In operation S607, the proxy proxy port is searched for in the relation using two of the group number registered in the proxy signaling agent and the extracted VPCI. Normally, you can find a proxy logical port that matches the group number and VPCI. If the VCI value is specified in the SETUP message with the VPI of the proxy logical port found as described above, it is allocated, otherwise an arbitrary VCI is allocated (S608). The proxy logical port found at this time may or may not be the same physical link as the proxy signaling agent. This is because the proxy signaling agent may be one of the proxy logical ports or the logical port of the general physical link type as described above.

In the case of No indication, the connection identifier is not included in the SETUP message. This means that it can be arbitrarily assigned in the network, and there is no restriction. In this case, first, the bandwidth is checked among the proxy ports that match the group number (S609), the VPCI value and the VPI are extracted from the proxy port that satisfies the bandwidth, and the VCI in the VPI is allocated (S610). The VPCI and the allocated VCI are put in the connection identifier of the message and transmitted to the PSA 331 (S611).

Thereafter, the call continues and the ATM service is started through the connection identifier selected at the time when the service of the call starts.

The above detailed description and contents of the drawings are to be construed as illustrative and not restrictive of the invention. Accordingly, the scope of the invention should be determined by the appended claims.

The present invention has the following effects.

First, a similar function to that of the SVC function is possible without using a terminal having an ATM signaling function.

Second, since it has one subscriber address and uses it in the switching system, it has the same effect as using the entire proxy group's band for the other subscriber.

Third, even when connected to a private network, it is possible to control several links using the interface with the private network as one SVC link.

Claims (8)

A proxy signaling processing method in an asynchronous transmission mode switching system in which a plurality of user terminals are connected to different physical links, A first step of generating a proxy logical port of a user terminal that is a target of a proxy signaling service in a switching system; A second step of creating a signaling channel by generating a proxy signaling agent in the generated proxy logical port; And And receiving a proxy signaling call establishment request of the user terminal through the generated signaling channel of the proxy signaling agent, providing a connection identifier to the switching system according to the request of the proxy signaling agent. Proxy signaling processing method of asynchronous transfer mode switching system. The method of claim 1, wherein the first step, And a proxy logical port is generated in the logical port of the physical link type. The method of claim 1, wherein the first step, Receiving physical port type logical port, VPI, VPCI, proxy group number, forward bandwidth and reverse bandwidth information for proxy signaling call service according to an operator's request; Checking the presence or absence of a logical port corresponding to the input information and checking a range of the input VPI if a corresponding logical port exists; Checking the proxy group number and the bandwidth; And And generating and storing a new VPI logical port with the input information and outputting a result. The method of claim 3, wherein the bandwidth check, If the bandwidth is given, the proxy signaling processing method of the asynchronous transmission mode switching system, characterized in that the change according to the subtraction by the input forward and reverse bandwidth from the current remaining bandwidth of the physical link. The method of claim 1, wherein the second step, Receiving parameters for generating a proxy signaling agent using a number of VPI logical ports, a proxy group number, and a protocol type received from an operator; Checking whether or not the proxy group number matches the generated proxy logical port if the logical port exists corresponding to the input logical port number; Requesting and registering a signaling channel for a corresponding logical port; And And receiving notification of the registration result and notifying the operator to the operator. The method of claim 5, wherein the proxy group number, And a group number of the generated proxy logical port is input. The method of claim 1, wherein the third step, Receiving a call establishment request message from a proxy signaling agent through a proxy signaling channel; Checking whether a connection identifier is included in the message by checking suitability of the message or component information of the message; Allocating a VCI in a VPI in which a signaling channel of the proxy signaling agent is set when information of a connection identifier included in the message is VP-associate; If the information of the connection identifier included in the message is explicit-VPCI, identifying a corresponding proxy logical port according to the group number and the VPCI value and allocating a VCI at an assigned VPI of the port; Checking a bandwidth among proxy ports matching the group number when the message does not include a connection identifier, extracting a VPCI value and a VPI from a proxy port satisfying the bandwidth, and allocating a VCI in the VPI; And And including the corresponding VPCI and the allocated VCI in the connection identifier and transmitting the same to the proxy signaling agent to perform a connection control service. On your computer, A first function of generating a proxy logical port of a user terminal that is a target of a proxy signaling service in a switching system; A second function of creating a signaling channel by generating a proxy signaling agent in the generated proxy logical port; And A third function of providing a connection identifier to the switching system according to a request of the proxy signaling agent when receiving a proxy signaling call establishment request of the user terminal through the generated signaling channel of the proxy signaling agent; A computer-readable recording medium having recorded thereon a program for executing the program.