KR100248416B1 - Atm vlan service control method using b-isdn signal capacity - Google Patents

Abstract

The present invention provides an ATM terminal-to- ATM connection function over a wide area by Shortcut routing between ATM hosts or ATM routers that do not belong to the same IP subnet connected to the ATM switching system when providing an ATM VLAN service, which is a connectionless data service through the ATM network. . In other words, by implementing a built-in large-capacity address translation server that performs address translation function by NHRP, and in connection with the point-to-point, point-to-multipoint call / connection control and closed user group supplementary services of ATM switch, In addition, it provides functions to maintain security by limiting communication range and multicasting service within VLAN group without developing additional functions. By implementing the mapping function for ATM VLAN emulation, call / connection control, additional service, and ATM traffic control function by various signaling of ATM switching system are used as it is for providing connectionless data service. In addition, the address translation or routing information transmission channel is allocated as a permanent virtual channel in advance and transmitted to the VLAN server function performing portion, thereby reducing service delay due to address translation during IP packet transmission.

Description

A method for controlling wide area ATM VLA service using non-ISDN signaling capability

The present invention relates to a method for controlling ATM VLAN service using B-ISDN signaling capability, and in particular, to implement a built-in large-capacity address translation server that performs address translation function by NHRP, and B- in ATM system when setting IP packet transmission path. By applying ISDN signaling capability point-to-point, point-to-multipoint call / connection control, and closed user group supplementary service functions, not only data communication services between high-speed and large-capacity LANs, but also limit the scope of communication within a desired group or multicasting services within a VLAN group It provides ATM VLAN service control method using B-ISDN signaling capability, which enables various functions of B-ISDN signal processing function implemented in ATM switching system without constructing additional additional service server.

Existing data communication network is easy to multicast / broadcasting by using shared media in connectionless type, but it is difficult to guarantee the quality of service between band and end by data transmission by Best Efforts method, and bridge or router is required when interworking between networks. .

Accordingly, in order to apply ATM switching function suitable for providing high-speed and multimedia services to data processing, ATM VLAN technology in private networks such as LAN Emulation, IPOA, MPOA, etc. has been proposed in ATM-Forum and IETF.

However, these methods use the ATM switch only for the information transmission path and adopt the Client & Server method that adds a separate server to the ATM network to provide various services. As a result, it does not take full advantage of the ATM switch's ability to provide various B-ISDN signaling capabilities. In addition, the scope of service provision is mainly composed of a compass network or a corporate network between a small subscriber or a network in a private network area, and a service is provided using a server for each workgroup.

In addition, ITU-T proposed a connectionless server technology for public networks, but bottlenecks in processing large data traffic due to centralized routing processing in connectionless servers, and operation management, scalability and economy due to development of separate server devices It is difficult to meet the rapidly growing demand for disconnected data traffic and wide area services.

An object of the present invention is to implement a built-in large-capacity address translation server to perform the address translation function by NHRP, and to control the point-to-point, point-to-multipoint call / connection of B-ISDN signaling capability in ATM system when IP packet transmission path is established. By applying closed user group supplementary service function, not only data communication service between high-speed and large-capacity LAN, but also limiting the range of communication within the desired group or multi-casting service within VLAN group without exchanging ATM without establishing additional service server An object of the present invention is to provide an ATM VLAN service control method using B-ISDN signaling capability which enables the B-ISDN signaling processing function implemented in a system.

Means for achieving the object of the present invention is that when receiving an IP packet from the user, and whether the ATM address corresponding to the IP address of the called party in the cache memory, the ATM mapped to the destination IP address A first step of determining whether an address exists; a second step of checking whether an SVC connection is established for an ATM address mapped to a destination IP address as a result of the determination in the first step; and the second step As a result of the investigation in the process, if there is a set information transmission path, it is connected to the procedure of performing IP packet forwarding process. Receives the SVC connection information set in the address storage cache table, starts the duration timer for the connection, and encapsulates the IP packet. In the third process, which is transmitted through the ATM switching system and is in a dormant state, and if there is no ATM address mapped to the destination subscriber IP address as a result of the determination in the first process, a specific connection identifier initially determined for NHRP message delivery is initially determined. After requesting address translation request according to NHRP protocol to VLAN server in ATM switching system through persistent virtual connection, if NHRP response is received while waiting for NHRP response, ATM address is added to address storage cache table, ATM address maintenance time timer A fourth step of linking to the SVC call / connection control processing procedure, and a fifth step of deleting an ATM address from the address storage cache table and placing a dormant state when a timeout of the ATM address holding time timer occurs. If the timeout occurs, the SVC connection information is deleted from the address storage cache table. An IP packet processing step of the ATM client, which has a sixth process of notifying a call recovery request to the switching system and receiving a call recovery completion message while waiting for call recovery completion;

Receiving a NHRP request to obtain an ATM address corresponding to the called party's IP address from the ATM client, a first step of examining the existence of the ATM address by examining the ATM address storage table; If present, the ATM address is stored in the NHRP response message content and is transmitted to the ATM client. The ATM process corresponds to the second process, which is in the dormant state, and the IP address requested in the ATM address storage table. If no NHRP request is sent to the adjacent ATM switching system by using the contents of the routing information storage table, and the NHRP response notification is received while waiting for NHRP response, it is added to the ATM address storage table. ATM address storage cache table when the third process to enter the state and timeout of the ATM address hold time timer occur The fourth process of deleting the ATM address from the server and placing it in the dormant state, and upon receiving the call setup request from the ATM client, performs call / connection setup processing, sends the call setup request to the destination ATM client, and then waits for the call setup wait. When receiving the access notification, the fifth process of entering the busy state capable of transferring data through the ATM network, and when the IP packet encapsulated in the busy state is received, the ATM switching system transparently delivers to the destination ATM client side. If a call recovery message from the ATM client is received in the busy state, and the call recovery request is transmitted to the counter ATM client, the call recovery completion notification message is received while waiting for the call recovery completion. If so, it sends a call recovery completion message to the counter ATM client and goes to the ATM switching system consisting of the seventh process to be in the idle state. IP packet processing step.

1 is an ATM VLAN server configuration for providing ATM VLAN service.

2 is an IP packet processing flowchart in an ATM client.

3 is an IP packet processing flowchart in an ATM switching system.

(Explanation of symbols for the main parts of the drawing)

1,1 ': ATM host 2,2': ATM router

3,3 ': ATM switching system 4,4': ATM VLAN server

5,5 ': system manager

Existing connectionless data communication network is easy to multicast / broadcast by using shared medium, but it is difficult to guarantee service quality between band and end by data transmission by Best Efforts method. At the same time, a bridge or router was used.

Accordingly, ATM VLAN technology has emerged to apply the switching concept of ATM switches suitable for meeting high-speed and multimedia service needs even in connectionless data processing. However, these methods adopt a client & server method that uses an ATM switch only for a high-speed information transmission path. Therefore, it does not make full use of the function of ATM switch that provides various B-ISDN signaling capabilities, and additional service servers must be added to provide various services.

In addition, in the public network, a connectionless data communication method using a Permanent Virtual Connection (PVC) function of a ATM switch and a connectionless server (CLSF) is being promoted. However, due to the centralized routing processing in the connectionless server, the bottleneck of processing large data traffic and the operation management, scalability, and economics caused by the development of a separate server device are increasing. It is difficult to meet service needs.

Therefore, it reduces the service latency and provides direct end-to-end ATM connectivity without going through routers when communicating between VLANs belonging to ATM switching system. I need a way.

The present invention implements a large-capacity address translation server in an ATM switching system that performs address resolution by NHRP (Next Hop Resolution Protocol), and controls point-to-point and point-to-multipoint call / connection control and closure of an ATM switching system. In conjunction with additional services such as user groups, we provide more diverse services economically with superior quality.

ATM VLAN clients with ATM matching cards embedded in personal computers (PCs), workstations, and routers for ATM VLAN services, and perform NH VLAN emulation functions, and NHRP concept for ATM switching systems. A large-capacity address translation server function that performs address translation function and VLAN configuration management function are added, and connectionless IP packet is delivered through connected ATM network.

At the ATM client, when receiving an IP packet from the user, the ATM client checks whether an ATM address corresponding to the other party's IP address and information transmission path are set. That is, if there is no corresponding information in the cache memory, NHRP (Next Hop Resolution Protocol) is performed to obtain an ATM address corresponding to the IP address, and the switched connection by the B-ISDN signaling protocol is obtained from the ATM address. Set the Switched Virtual Connection to send the IP packet.

ATM exchangers can almost use point-to-point and point-to-multipoint call / connection control and closed user group supplementary services even when establishing IP packet transmission paths. Therefore, not only basic LAN-to-LAN data communication service by point-to-point connection, but also CUG service is provided to limit the communication range for security maintenance. It also provides multicasting within VLAN groups with point-to-multipoint connection handling that specifies VLAN group identifiers. In other words, B-ISDN signaling capability of ATM switching system can be applied as it is in case of providing connectionless data service without developing additional functions, thereby improving service quality and satisfying various service requirements.

In addition, by applying the NHRP concept, short-cut routing between ATM terminals belonging to the same IP subnet connected to the ATM switching system, as well as between ATM hosts or ATM routers, and between ATM clients not belonging to the same IP subnet can be used for short-term routing. Provide over.

1 is a configuration diagram of an ATM VLAN server for providing an ATM VLAN service.

It is an ATM host (1) (1 '), which is a PC or workstation with an ATM matching card and VLAN emulation, and an ATM router (2) (2'), a router with an ATM matching card and VLAN emulation. The ATM client is composed of an ATM switching system (3) (3 ') that performs a PVC connection control function and an SVC call / connection control function using various B-ISDN signaling protocols.

Within the ATM switching system, address translation according to NHRP and routing protocols and the internal address resolution table (6) (6 ') of other ATMs belonging to the switching system to provide VLAN services. To manage the External Address Resolution Table (7) (7 ') of each ATM client and Routing Table (8) (8') for address translation with other switching systems A large VLAN server function (4) (4 ') is added.

In addition, the function of performing VLAN configuration management is added to the operation function of the ATM switching system by the system administrator (5) (5 ').

2 is a flowchart illustrating processing of an Internet Protocol (IP) packet in an ATM client.

When receiving an IP packet from the user (S1), it is checked whether there is an ATM address corresponding to the IP address of the called party in the cache memory (S2). If there is an ATM address mapped to the destination IP address (S3), it is checked whether an SVC connection is established (S4). If there is an established information delivery path, the procedure is performed to perform an IP packet forwarding process. If there is no information delivery path, a call setup request is made to the ATM switching system (S5), and the call setup wait state is entered (S6).

At this time, upon receiving a call connection notification (S7), the SVC connection information set in the address storage cache table is stored (S8), and after the maintenance time timer of the connection is driven (S9), the IP packet is encapsulated (S10). It passes through (S11) and becomes a dormant state.

If there is no ATM address mapped to the destination subscriber IP address, an address translation request according to the NHRP protocol is requested to the VLAN server in the ATM switching system through a permanent virtual connection initially using a specific connection identifier predetermined for NHRP message delivery. S12) NHRP response waiting state (S13).

At this time, when the NHRP response is received (S14), the ATM address is added to the address storage cache table (S15), the ATM address holding time timer is driven (S16), and then linked to the SVC call / connection control procedure (S16).

In addition, if a timeout of the ATM address holding time timer occurs (S17), the ATM address is deleted from the address storage cache table (S18) and is in a dormant state.

When the timeout of the connection hold time timer occurs (S19), the SVC connection information is deleted from the address storage cache table (S20), and a call recovery request is notified to the ATM switching system (S21). S22). At this time, if a call recovery completion message is received (S23), the state becomes idle.

3 is an IP packet processing flowchart in an ATM switching system.

When receiving an NHRP request for obtaining an ATM address corresponding to the called party's IP address from the ATM client (S101), the ATM address storage table is examined (S102). If the ATM address exists (S103), the ATM address is stored in the NHRP response message content and transmitted to the ATM client (S104).

If there is no ATM address corresponding to the requested IP address in the ATM address storage table, the NHRP request is transmitted to the adjacent ATM switching system using the contents of the routing information storage table (S105), and the NHRP response wait state is reached (S106). .

At this time, when the NHRP response notification is received (S107), it is added to the ATM address storage table (S108), and the ATM address holding time timer is driven (S109).

In addition, when a timeout of the ATM address holding time timer occurs (S110), the ATM address is deleted from the ATM address storage cache table (S111) and becomes a dormant state.

Upon receiving a call setup request from an ATM client (S112), various B-ISDN signaling capabilities for point-to-point or point-to-multipoint call / connection control and closed user group service processing are analyzed by analyzing call setup message content and subscriber service profile information. The call / connection establishment process is performed (S113), the call setup request is transmitted to the destination ATM client (S114), and the call setup wait state is entered (S115). At this time, upon receiving the call connection notification (S116), the call is in a busy state capable of transferring data through the ATM network (S117).

When the encapsulated IP packet is received in a busy state (S118), the ATM switching system transparently forwards the incoming ATM client side (S119) and returns to the busy state (S120). The call recovery message from the ATM client is transmitted. Upon reception (S121), the call recovery request is transmitted to the counterpart ATM client (S122), and the call recovery completion wait state is entered (S123). At this time, upon receiving the call recovery completion notification message (S124), the call recovery completion message is transmitted to the counter ATM client (S125), and the state becomes idle.

The present invention provides the same IP subnet as well as between an ATM host or an ATM router which is an ATM client belonging to the same IP subnet connected to an Asynchrous Transfer Mode (ATM) switching system. Shortcut routing provides ATM-to-ATM connectivity across a wide range of ATM clients.

In addition, the present invention provides a point-to-point (PtP) and point-to-multipoint (PtMP) call / connection control and closed user group (CUG: Closed) of an ATM switch when establishing an IP packet transmission path. User Group) By connecting with supplementary services, not only data communication between basic LANs, but also additional services such as services that maintain security by limiting communication range within a desired group or multicasting services within a group of virtual LANs. Provide without development. In addition, the signal processing function of B-ISDN, which is continuously developed further, can be applied as it is when providing a connectionless data service. The VLAN configuration management server function is implemented in addition to the operation function of the ATM switching system to provide a good level of functionality at a minimum cost.

Claims (3)

A first step of processing an IP packet at an ATM client; A method of controlling a wide area ATM VLAN service using B-ISDN signaling capability, comprising a second step of processing an IP packet in an ATM switching system. The method of claim 1, In the first step, when the IP packet is received from the user, the first step of determining whether there is an ATM address mapped to the destination IP address by checking whether there is an ATM address corresponding to the IP address of the called party in the cache memory. 1 course; A second step of checking whether an SVC connection is established for an ATM address mapped to a destination IP address as a result of the determination in the first step; As a result of the investigation in the second process, if there is an established information transmission path, the procedure is performed to perform an IP packet forwarding process. If there is no information transmission path, a call establishment request is made to the ATM switching system. A third step of, upon receiving the call connection notification, storing the SVC connection information set in the address storage cache table, running the maintenance time timer of the connection, encapsulating the IP packet, delivering the packet through the ATM switching system, and stopping the service; If there is no ATM address mapped to the destination subscriber IP address as a result of the determination in the first step, ATM address exchange request according to NHRP protocol is exchanged through a permanent virtual connection using a specific connection identifier initially determined for NHRP message delivery. After making a request to a VLAN server in the system and receiving an NHRP response while waiting for an NHRP response, an ATM address is added to the address storage cache table, an ATM address retention time timer is started, and an SVC call / connection control procedure is executed. 4 courses; A fifth step of deleting an ATM address from an address storage cache table and placing a dormant state when a timeout of the ATM address holding time timer occurs; When the connection maintenance timeout timeout occurs, the SVC connection information is deleted from the address storage cache table, and the call exchange request is notified to the ATM switching system. A method for controlling a wide area ATM VLAN service using B-ISDN signaling capability, comprising the sixth step. The method of claim 1, The second step includes a first step of checking whether an ATM address exists by checking an ATM address storage table when receiving an NHRP request for obtaining an ATM address corresponding to a called party IP address from an ATM client; A second step of storing an ATM address in an NHRP response message and transmitting the ATM address to an ATM client if the ATM address exists as a result of the investigation in the first step; If there is no ATM address corresponding to the requested IP address in the ATM address storage table, the NHRP request is transmitted to the adjacent ATM switching system by using the contents of the routing information storage table. A third step of, upon receiving the NHRP response notification, adding to the ATM address storage table, driving an ATM address holding time timer, and placing a dormant state; A fourth step of deleting an ATM address from an ATM address storage cache table and placing a dormant state when a timeout of the ATM address holding time timer occurs; When a call establishment request is received from an ATM client, the call / connection establishment process is performed, and when a call connection notification is received while waiting for call establishment, after a call establishment request is transmitted to the destination ATM client, the call can transmit data through the ATM network. A fifth process of becoming in a heavy state; A sixth step of, when the encapsulated IP packet is received in a busy state, the ATM switching system transparently forwards the incoming ATM client to the called ATM client; When a call recovery message is received from an ATM client in a busy state, a call recovery request is sent to the other ATM client. When a call recovery completion notification message is received while waiting for call recovery completion, a call recovery completion message is sent to the other ATM client. And a seventh process of going to a dormant state.

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