KR950012324B1 - Call setup method of partialy centeralized aim switching node - Google Patents

Abstract

The method comprises the steps of controlling a connection by classifying and assigning the traffic of a service command from a user; looking for an output port of a corresponding switch network to which a user information is transmitted, the user information being obtained by translating a logic terminalling subscriber number inputted in a call set; and assigning an information transmission path of transmission and terminalling parts.

Description

Call setup method of partially centralized ATM switching node

1 is a hardware diagram of an ASM switched node.

2 is a diagram illustrating a traffic control process to be performed in an ASM network.

3 is a flow chart for connection consignment control for band allocation in an ASM network.

4 is a flowchart of a number translation function of a called subscriber.

5 is a process flow diagram for assigning information transmission paths of a calling party and a called party.

The present invention relates to a call setup method of a calling party and a called party for continuously and stably providing a service required from a subscriber station among functions to be performed at each node of an exchange in an ASM exchange.

ATM (Asychronous Transfer Mode) technology exchanges communication information with various speeds and attributes by unit of 53 octets of cell units, and logical channel numbers assigned to links between nodes during call establishment through statistical multiplexing. It operates at a line speed of 155Mb / s or more in a way that the network is exchanged at high speed by a virtual line based on the Therefore, it is desirable to design the system to be easy to structure and control while satisfying various communication requirements.

The services provided in the ASM environment exhibit various traffic characteristics such as the maximum generation rate and average generation rate of information, burst index, and average length of burst intervals. Therefore, the ASM network is designed to satisfy the efficient operation of network resources and the quality of service requirements. There is a need for highly effective traffic control techniques such as predicting traffic changes and preventing congestion. Therefore, it is necessary to perform a traffic control function to prevent the congestion condition and to minimize the effect of congestion when congestion occurs by continuously performing call admission control, priority control, and congestion control functions from the entrance of the network to the completion of the call.

Existing call processing technology mainly used to process voice and continuous zeta, but modern society provides communication network of high speed communication including high speed data communication, still picture, and dynamic picture transmission service according to the development of information communication. This is required.

Accordingly, an object of the present invention is to provide a basic processing method for call setup for satisfying a service request of a user in an ASM exchange.

In order to achieve the above object, the present invention provides a call setup method applied to an ASM switching system having a plurality of subscriber switching modules performing a aggregation function and a central access module performing a connection function between the subscriber switching modules. The first step of performing the connection admission control by classifying the traffic of the service for the service request of the fixed speed traffic and the variable speed traffic to allocate the use band for the service request, and after performing the first step, A second step of finding a physical output port of the Hidin switch network to which the user information is transmitted by translating the logical called party number entered during the relay call setup process; and after performing the second step, transmitting information of the originating and called party And a third step of allocating a path.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention;

1 is a hardware configuration diagram of an ASM switching system, and includes a central access module 2 (CIM) that performs a connection function between an access switching module (ASM) and an ASM 1 performing basic aggregation functions. It has a modular structure consisting of Central Interconnection Moldule.

ASM can operate independently with minimal system configuration, in large systems many ASMs act as concentrators with constant concentrating ratios, and CIM acts as a dispensing unit for large systems.

ASM has built-in single stage N × N magnetic routing switch module, and the call processor part (CPP) (3) and signal processor (SHP) (SHP) 4) and the matching master IP (Interface Part: SIM, TIM) (5).

ASM, a concentrator, is a non-blocking magnetic routing switch that performs a concentrator function with a constant concentrating ratio according to the system configuration.One-to-one service is controlled by SCP / TCP and multiple Servicon CIM Access Switch Nerwork Module (ASNM) (6), which is connected under BCP control of BCP and destination ASM, terminates information cells on UNI / NNI protocol and handles signaling information along with SCP, TCP, and BCP. Subsrider Call Procssor that performs overall traffic control such as call admission control, user / network parameter control, priority control, and congestion control along with subscriber matching circuit. (7), a processor that performs call processing with a network using a protocol, performs call connection control for I / O calls with a relay line matching circuit, and matches with a network. TCP (Trunk Call Processor) (8) to manage the necessary functions, Broadcasting Call Processor (BCP) (9) to control call access for providing multiple access-related (broadcast) services, ASM (1) and CIM (2) in the system It is composed of a Link Interface Module (LIM) 10 that provides an Inter Module Interface (IMI) protocol dedicated to an internal cell format as a Wrinkle Matching Module between Rx.

CIM (2) is a module for managing the traffic state of all links, the TFCP (Traffic Control Processor) (11) for selecting and notifying the optimal information transmission path according to the request of the originating ASM (1), NTP for number translation (Number Transnation Processor) 12, BCP (Broadcasting Call Processor) to control call connection for providing multiple access related (broadcast) service, GSP (Global Service Processor) 13 to control recording announcement, CIM (2) A non-blocking self-routing switch composed of a single path as a switch network, used as an interconnector with ASNM, and performs multiple access functions under the control of BCP for broadcast call processing. 14).

2 is a flowchart of interworking of the traffic control function to be performed in a call processing block in an ASM network. When a call establishment request is received from the terminal 15, the switching node determines a bandwidth or loss required by the switching node. Call reception control (16) considering the current flow rate, flow average, bit, burst length measurement, and loss tag of excess cell from matching unit. If the call connection is possible by receiving the line capacity and routing control of the traffic data being managed (17), it is compared with the result of the flow monitoring (18) and transmitted to the output buffer (20) through the magnetic routing switch (19) of the node. During the call processing, the output buffer is acknowledged by quality control for quality assurance for service quality assurance and quality control such as dropping of marked cells in case of congestion. The call proceeds. In order to efficiently control various types of traffic in the ASM network, it is necessary to divide and operate the network level, the call level, and the cell level. At the network level, path setting and band allocation for a virtual path (VP), which is an in-network resource, are performed, and at the call level, call admission control is performed using parameters notified to the network by the terminal at the time of call establishment and a virtual channel (VC Path setting) is performed. In addition, it has a monitoring function that determines whether the traffic of the call being communicated at the entrance of the network operates within the prescribed value declared at the call setup, and in order to satisfy the required quality according to the traffic situation in the network when the regulation is violated. It performs functions such as discarding, priority control of the traffic flow, and cell buffer management.

FIG. 3 shows the entire network because the ASM network needs to combine the bandwidth of the connection path between the calling party and the called party and the state of the connection node in order to control connection admission for allocating a use band for the service request of the user. It is necessary to manage the resources and nodes of the entire network because the status of resources and nodes must be comprehensively performed.The traffic of required services is classified into constant-speed traffic and variable-speed traffic. It is a flow chart to decide whether to do it.

The total bandwidth accommodated in the network is allocated to the constant speed traffic band (Cc), the variable speed traffic band (Cv), and the spare band (Cp) by using statistics on the ASM traffic (21).

The B-ISDN terminals report the traffic descriptors to the network using the virtual path and virtual channel allocated through the meta-signalling procedure (22).

The network uses the reported traffic descriptor to determine whether the type of traffic is constant speed or variable speed traffic (23).

In the case of constant / variable speed traffic, it is determined whether the quality of service requirements (QOS) are satisfied within the constant / variable speed band (Cc / Cv) (24), and if the fox band exists, the connection is accepted (25). Band extension analysis is performed through the spare band Cp in the block 26.

If band extension is possible, accept the connection (27). Otherwise, it determines whether the call is for a high-priority service (26). If it is a high-priority service, it accepts the connection if it can be allocated within the free band threshold (29). If it refuses the connection (30).

4 is an algorithm for finding a physical output port address of a corresponding switch network to which user information is transmitted by translating a logical called party number inputted during a subscriber call or relay call setup process.

When the called party's translation request is received for the middle call or the local call according to the request of the ASM (1) control unit, the call processing processor (CPP) of the aggregation group receives the call type (outgoing call, own station) through the called party's subscriber number. After identifying the call (or incoming call) (32), number translation is performed according to the following procedure.

Analysis of the called party number (33) distinguishes international calls, long distance calls and local calls (34).

For international calls (35), find the ASM number to which the corresponding route for the country code (CC) belongs in the called party number, and for the out-of-country (36), refer to the Nation Destination Code (NDC) among the called party numbers. Find the ASM (1) number to which the corresponding route of) belongs, and find the ASM (1) number to which the corresponding route of national data (prefix) belongs among the called subscriber number in the case of a local call (37).

The physical link ID corresponding to the CC (or NDC, prefix) is obtained from the ASM 1 to which each loop belongs (38).

The number of the output ASM 1 is obtained through the station data and the called number (39). The physical link ID of the station data and the called number is obtained from the output ASM 1 (40).

Figure 5 shows that in the CCITT I.361, a cell defined as a 5-octet header and a 48-octet information area is used for routing within the ASM switching system to switch it to the called party according to the signal information. Additional information is converted into the added internal cell form.

When the user requests a call, the call processing processor (CPP) performs connection admission control and requests path allocation to the TMCP in the CIM (41). The TFCP can satisfy the service request by considering the state of the virtual path and the virtual channels. The virtual path and the virtual channel for the calling party and the called party are allocated (42) and notified to the CPP of the calling party (43) and the called party (944). Routing information of the switch network is attached through the internal signaling channel with the destination ASM 1 in the switching system (45), and the CPP at the source side updates the input header conversion table for VPI ₁ / VCI ₁ (46), The output side CPP updates the output header translation table to VPI ₀ / VCI ₀ (47).

Cells with VCI ₁ inputted from the user are converted into an internal cell structure having routing information by the input header conversion table, and then reached by the destination header aggregation table according to the routing information. It is converted into an external cell structure (structure defined in CCITT) having an output VPI ₀ / VCI ₀ , and information is transmitted 48 to the network to complete call setup.

The present invention carried out by the above processing procedure has the effect of contributing to the performance improvement and realization of the call processing function of the ASM system by providing a basic call setup algorithm that is easy for efficient management of network resources and additional functions.

Claims (4)

A call applied to an ASM switching system having a plurality of subscriber exchange modules (ASM; 1) that perform aggregation functions and a central access module (CIM; 2) that performs a connection function between the subscriber exchange modules (ASM; 1). A setting method comprising: a first step (21 to 30) of classifying traffic of services for a user's service request into constant speed traffic and variable speed traffic, and allocating a use band for the service request to perform connection admission control; After performing the first step 21 to 30, the second step of finding the physical output port of the corresponding switch network to which the user information is transmitted by translating the logical called party number entered in the subscriber call and the relay call setup process. (31 to 40), and after performing the second step (31 to 40), the third step (41 to 48) for allocating the information transmission path of the calling party and the called party Chung way. The method of claim 1, wherein the first steps 21 to 30 allocate a constant speed traffic band Cc, a variable speed traffic band Cv, and a spare band Cp to the total band accommodated in the ASM network. If the descriptor is reported, the network determines the type of traffic (21 to 23), and after performing the steps (21 to 23), in the case of constant variable speed traffic, the service is provided in a constant / variable speed band (Cc / Cv). Determining whether the required quality is satisfied and accepting the connection if there is a free band, otherwise performing band extension analysis through the free band Cp in the network (24 to 26), and the steps (24 to 26). After execution, accept the connection if bandwidth expansion is possible, otherwise, determine whether the priority is high, and if the priority is high, accept the connection if it can be allocated within the threshold of the free band, and for services that are not high priority, Decline connection Call setting method characterized in that it is carried out with a step (27 to 30). The call processing processor (CPP) of the concentrating group is set to be international if the called party's translation request for the outgoing call is received at the request of the ASM (1) call controller. Steps 31 to 34 for distinguishing a call, a long distance call, and a city call, and after performing the steps 31 to 34, in case of an international call, an ASM (1) to which a corresponding root for a country code (CC) of the called party number belongs. ) If it is a long distance call, find the ASM (1) number to which the corresponding route of the area code (NDC) belongs to the outbound subscriber number. (35 to 38) to find the physical link identifier, and when the called party's translation request for the local call and the incoming call comes in according to the request of the ASM (1) call controller, Find out the number of output ASM (1) And (31, 32, 39, 40) obtaining a physical linkage identifier of the station data and the called number. The method according to claim 1, wherein the third steps 41 to 48 allocate a virtual path and a virtual channel to the calling party and the called party when a path allocation request is received from the traffic control processor (TFCP) in the CIM (2). (41 to 44) of notifying the calling processor and the called party's processing processor (CPP), and after performing the steps 41 to 44, routing information of the switch network is attached, and the calling and output call processing processors are attached. Update (45 to 47) the most common path identifier (the input header conversion table for the most channel identifier), and after performing the steps (45 to 47), the information is converted into an external cell structure according to routing information and transmitted to the network. And a step (48).