KR100204486B1 - Method of controlling call and connection in atm user network interface - Google Patents

Abstract

The present invention is a sequence of detecting received narrowband bearer capability (NBC) information elements, and the present invention comprises the steps of: storing the received information elements in a memory area (S1); Determining whether it is a narrowband bearer capability information element identifier (S2); Detecting a bit value corresponding to a coding standard, a flag, and an information element action indicator in the case of the narrowband bearer capability information element identifier (S3); Detecting a length of narrowband bearer capability content (S4); Detecting an information transmission capability bit (S5); Detecting a transmission mode and an information transmission rate (S6); Detecting a structure, a form, and a setting bit (S7); detecting a symmetry and information rate (S8); Detecting a user information layer 1 protocol (S9); detecting a synchronous / asynchronous, compromise and user rate (S10), an adjustment rate, an originating network independent clock, a receiving network independent clock, an originating flow control, a receiving side Detecting bit values corresponding to flow control or header / nonheader, multi-frame support, mode, logical link identification compromise, assigner / quantifier and in-band / out-band negotiation bit (S11); number of stop bits, data bits Detecting number and parity (S12); Detecting a duplex mode and a modem type (S13); Detecting a user information layer 2 protocol (S14); In step S15, the user information layer 3 protocol is detected, and according to the present invention, since the Q.2931 protocol can be applied in the ATM user network interface, it is possible to easily establish a channel connection for transmitting data in the ATM method. have.

Description

Method of controlling call and connection in ATM user network interface

1 is a conceptual diagram illustrating a general ATM protocol reference model.

2 illustrates a typical B-ISDN call control protocol stack.

3 is a format diagram showing the structure of an ATM cell.

4 is a diagram showing an example of a flow of call processing related messages in an ATM user network interface UN1.

5 illustrates the general format of call processing related messages in an ATM UNI.

FIG. 6 is a diagram showing a format for a narrowband bearer capability (NBC) information element of the information elements shown in FIG.

7 is a block diagram showing a configuration of hardware for performing the method according to the present invention.

8 is a flowchart of a method for detecting a received narrowband bearer capability information element among information elements included in a call processing related message according to the present invention.

* Explanation of symbols for main parts of the drawings

1: Calling Party 2: Network

3: Called Party 10: Message Generator

11: Host CPU 12: Storage

12-1: DRAM 12-2: DRAM control unit

12-3: ROM 12-4: Nonvolatile RAM

20: ATM card 21: packet memory

22: control memory 23: AAL unit

23-1: AAL cutout 23-2: AAL recombination

24: ATM layer and physical layer unit

The present invention provides a method for controlling calls and connections in a user-network interface (hereinafter referred to as UNI) in an asynchronous transfer mode (hereinafter, referred to as ATM). In particular, the present invention relates to a method for detecting an information element regarding narrowband bearer capability (NBC) received from an information element (IE) included in a call processing related message in an ATM user network interface. .

Due to the rapid development of information society, users' communication service demand has increased, and Broadband Integrated Services Digital Network (hereinafter referred to as B-ISDN) has emerged as the next generation communication network. The ATM method, which is an asynchronous delivery mode, can be used as a basic delivery means to accommodate various services regardless of bandwidth and speed.For the ATM processing, the signal adaptation layer (Signalling AAL), Q.2931, B-ISUP, etc. The same draft is proposed.

That is, in the conventional ISDN (also referred to as narrowband N-ISDN), the transmission rate of a channel carrying user information was about 64 Kbps to about 2 Mbps, so it was difficult to satisfy broadband services such as moving pictures.

On the other hand, B-ISDN can transmit data at high speed of 100 Mbps or more, and can process various information sources such as voice, data, document image using ATM technology.

In the conventional N-ISDN, the signaling method for realizing access control uses Digital Subscriber Signaling System 1 (DSS1) in the subscriber line section and the No.7 common line signaling method in the inter-station relay section. DSS1 implements Layer 2 and Layer 3 protocols on the D-channel, also called Link Access Procedure on the D-channel (LAPD), and is recommended by ITU-T specifications Q.921 and Q.931. In the current B-ISDN, Q.2931 has been proposed into the draft by adding functional elements of Asynchronous Transfer Mode (ATM) to Q.931 as the signaling procedure of the user network interface (UNI), and the network-node interface (NNI) As a signaling procedure, B-ISUP (ISDN User Part) was proposed into the draft.

On the other hand, apart from the standardization of B-ISDN, which is centered on ITU-T, the computer and telecommunications industry, academia, government agencies and research institutes participate to promote the development of ATM technology and accelerate the development of ATM products and services. The ATM Forum was established in October 1991 and worked closely with standardization organizations (ANSI, IEEE, ITU-T, etc.) to support ATM UNI specification V3.0 (93.9) and ATM B-ICI Specification V1.0 ( 93.8), draft proposals such as ATM DXI Specication V1.0 (93.8) were established.

The role of the ATM Forum is not to duplicate the work of international standards bodies, but to complement and accelerate the standardization process by establishing standards that can be implemented in a short period of time.

The present invention is to realize the call and access control in the ATM (User-Network Interface) in accordance with the Q.2931 standard of call / access control in the user network proposed by the International Organization for Standardization as described above. It is an object of the present invention to provide a method for detecting an information element on Narrowband Bearer Capability (NBC) received among information elements (IE) included in a call processing related message.

The method of the present invention for achieving the above object is to detect an information element included in the user network interface message to communicate by ATM method from one end connected to the ATM network to another terminal connected to the network. A method, comprising: a first step of storing in a received information element memory area; Determining whether the information element identifier stored in the memory area is a narrowband bearer capability information element identifier; A third step of detecting a bit value corresponding to a coding standard, a flag, and an information element action indicator when the information element identifier stored in the memory area is a narrowband bearer capability information element identifier as a result of the determination in the second step; Detecting a bit value corresponding to the length of the narrowband bearer capability content; Detecting a bit value corresponding to the information transmission capability; Detecting a bit value corresponding to a transmission mode and an information transmission rate; A seventh step of detecting bit values corresponding to the structure, form, and setting; An eighth step of detecting bit values corresponding to symmetry and information rate; Detecting a bit value corresponding to the user information layer 1 protocol; Detecting a bit value corresponding to a synchronization / asynchronous bit, a compromise bit, and a user rate according to the user information layer 1 protocol detected in the ninth step; According to the user information layer 1 protocol detected in the ninth step, the adjustment rate, the calling network independent clock, the receiving network independent clock, the calling side flow control and the receiving side flow control or header / beheader, multiple frame support, mode, logic An eleventh step of detecting bit values corresponding to link identification compromise, assignor / quantizer, and in-band / out-band negotiation bits; Detecting a bit value corresponding to the number of stop bits, the number of data bits, and the parity; Detecting a bit value corresponding to a dual mode and a modem type bit; Detecting a bit value corresponding to the user information layer 2 protocol; And a fifteenth step of detecting a bit value corresponding to the user information layer 3 protocol.

That is, according to the present invention, the received narrowband bearer capability information element is detected among the information elements included in the call processing related message in order to realize call and access control in the ATM user network interface.

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

First, to explain the ATM system to which the present invention is applied in order to facilitate understanding of the present invention.

1 is a conceptual diagram illustrating an ATM protocol reference model, and is composed of a management plane, a control plane, and a user plane, and the management plane is divided into hierarchical management and plane management.

Here, the plan management refers to the overall management of the system, and the hierarchical management refers to management and operation and maintenance (OAM) information management of resources and usage variables.

In addition, the control plane observes call control and connection control information, and the user plane manages the transfer of user information.

Protocols of the control plane and user plane are divided into upper layer, ATM adaptation layer, ATM layer, and physical layer. The functions of each layer are shown in Table 1 below.

As shown in Table 1, the ATM scheme is divided into vertical structures such as a physical layer, an ATM layer, an ATM adaptation layer (AAL), and a higher protocol layer, and the AAL layer is divided and reconstructed sublayer (SAR). Segmentation And Reassembly sub layer (CS) and Convergence Sublayer (CS) are divided into physical layer (PM) and Transmission Convergence (TC) sub-layer.

In addition, the user network interface (UNI) is implemented as Q.2931 in Layer 3 of the control plane to control calls and connections between ATM networks and users, and Q.2931 is an ISDN layer. As a higher standard of Q.93B, which extends Q.931, which is 3 protocols, the basic call / connection control standard proposed by ITU-T used in User-Network Interface (UNI) Layer 3 for B-ISDN (User Network). Interface Layer 3 Specification for Basic Call / Connection Control).

In addition, the network interface (NNI) is implemented as B-ISUP in Layer 3 of the control plane, and the relevant ITU-T standard is Q.2761-Q.2764.

Next, look at the call control protocol standards of the B-ISDN to which the present invention is applied.

As shown in FIG. 2, the UNI call control protocol in the User Network Interface (UNI) is defined as Q.2931, and the Service Specific Connection Oriented Protocol (SAAL SSCOP) of the signaling AAL layer is defined as Q.2931. 2130 and Q.2110. The AAL Service Specific Coordination Function (SSCF) is defined as I.363, the ATM layer is defined as I.361, the physical layer is defined as I.432, and the network node interface (NNI). ), The user part (B-ISUP: B-ISDN User Part) is Q.2761-Q.2764, and the message transfer part 3 (B-MTP: B-ISDN Message Transfer Part 3) is Q.2210, SAAL SSCOP is defined as Q.2140 and Q.2110, respectively, AAL SSCF layer is set as I.363, ATM layer is I.361 and physical layer is I.432.

Comparing these protocols with the corresponding layer of Open System Interconnection (OSI), Q.2931 and Q.2761-Q.2764 correspond to OSI layer 3, SAAL SSCOP, AAL SSCF correspond to OSI layer 2, and ATM layer. The physical layer corresponds to OSI layer 1.

In other words, the Q.2931 message of layer 3 is segmented into 48 bytes (hereinafter referred to as octets) through the SSCOP, SSCF, and CPCS of the signaling adaptation layer (Signalling AAL5). After a 5 byte header is added, it is mapped and transmitted to a plurality of 53 byte ATM cells.

3 is a diagram illustrating a general ATM cell format, and is divided into a 5-byte header and a 48-byte payload. The 5-byte header structure used in the user network interface (UNI) is shown in FIG. One byte consists of four bits of Generic Flow Control (GFC) and four bits of Virtual Path Identifier (VPI), and the second byte consists of four bits of Virtual Path Identifier (VPI) and four bits. It consists of a Virtual Channel Identifier (VCI), the third byte is composed of an 8-bit virtual channel identifier (VCI), the fourth byte is a 4-bit virtual channel identifier (VCI) and 3 bits paid It consists of a load type (PT: Payload Type) and a 1-bit cell loss priority (CLP: Cell Loss Priority), and the fifth byte consists of 8 bits of header error control (HEC).

4 is a diagram illustrating an example of a call processing related message flow in an ATM user network interface (UNI), which is a call between a calling party (1), a network (2), and a called party. Indicates call processing.

First, a virtual channel connection (VCC) is always established through a signal adaptation layer (Signalling ALL) for call and access control, and call / access control messages are transferred to and from the virtual channel. data) To control access for forwarding, the message used for call access control is a message for B-ISDN call / access control as shown in Table 2 and a call / connection between N-ISDN and B-ISDN as shown in Table 3 below. The messages used for control and the messages used for the global call reference are shown in Table 4 below.

In FIG. 4, the messages of Tables 2-4 generated according to Q.2931 are transmitted using the 'AAL-DATA-REQUEST' primitive of the signal AAL (SAAL).

After setting up the setup message to set up the call of the calling party (1), it transmits to the network through the assigned signal virtual channel (VCI = 5) and simultaneously starts the timer T303 and calls the initialized state (Call Initiated state). Becomes

At this time, the setup message includes a call reference, various information elements required for call processing (for example, called part number, ATM user cell speed, broadband bearer capability, and service quality parameters). QoSP), etc.).

If there is no response for the time set by timer T303, the setup message is retransmitted, and if there is no response even after repeating the predetermined number of times, call processing is stopped.

After receiving the setup message, the network 2 selects and assigns a valid connection identifier (VPCI / VCI), and then sends a setup message to the called party 3 again. Send it to 1).

At this time, the caller 1 is in response to receiving the call procedure message and stops T303, starts the timer T310, and then goes to the outgoing call procedure state.

The called party 3 receives the setup message and then transmits a call procedure (CALL PROCEEDING_ and ALERTING) message to the network 2, and the network 2 receives the alerting message, and then sends it to the caller 1 ), The call forwarder (Call Delivered) state, the caller (1) is received when the alert message is received and stops T303 or T310 and enters the call forwarding state.

When the called party 3 generates a CONNECT message to allow the connection and transmits the message to the network 2, the network 2 transmits the message to the caller 1 as well as the CONNECT ACK message. Is transmitted to the called party 3 side, and a connect acknowledgment message is received from the caller 1.

Through the call processing process as described above, a communication path (connection) given as a connection identifier (VPCI / VCI) is formed between the originator 1 and the called party 2 so that data can be transmitted and received.

On the other hand, the user (receiver or sender) who wants to disconnect from the end of the data transmission or during the transmission generates RELEASE message and starts the timer T308 to request the network to disconnect and then release the request. (Release Request state), when the network receives the release message, it releases the virtual channel connection, sends the release message to the other party, informs it, delivers a RELEASE COMPLE TE message to the release request side, and returns null. ) State.

When the user (sender or called party) requesting the connection release receives the RELEASE COMPLETE message, the timer T308 is stopped, the virtual channel, the call number, etc. are released, and the status is null.

At this time, the user or the network can generate a (STATUS ENQUIRY) message at any time and request information about the network or other user's status, and the user or the network receiving the status request message is the status (STATUS). Create a message to let you know your status.

5 is a diagram illustrating a general format of a call processing control related message in an ATM user network interface (UNI), in which 1, ..., 8 at the top represent bits, and 1, 2, ... 0. at the right side. etc indicates octets (bytes).

As shown in FIG. 5, the first octet is a Protocol Discrimina tor, Q.2931 is 00001001b, bits 8 to 5 of the second octet are 0000b, and bits 4 to 1 are call reference values ( call reference value) in length in octets, typically 0011b.

The third to fifth octets represent a call reference value, and in particular, bit 8 of the third octet is a reference flag, which is 0, from the side (usually, the caller side) that generates a call reference. 1 indicates a message to be sent, and a value of 1 indicates a message sent to the side (usually the sender) that generates the conference. If the call reference values are all 0b, it represents a global call reference, and if it is all 1b, it represents a dummy call reference for semi-permanent virtual channel connection (SPC). .

The sixth and seventh octets indicate message type related information, and messages are classified according to the sixth octet value as shown in Table 5 below.

In addition, bit 8 of the seventh octet indicating message type related information is normally an extension, bits 7 and 6 are 00b as a spare, and bit 5 is 0b as a message type flag (Flag). Indicates that the message instruction field is not important, with 1b followed by an explicit instruction.

Bits 4 and 3 are spares, respectively 0b, bits 2 and 1 are message action indicators, 00b indicates a clear call, and 01b indicates Discard and ignore. 10b represents Discard and report status, and 11b represents Reserved.

In addition, the eighth and ninth octets represent a message length and may have a maximum length of 64K (2 ¹⁶ ) octets, followed by a variable length information element (IE) from the tenth octet (etc).

FIG. 6 is a diagram illustrating the format of a narrowband bearer capability information element among information elements (IE) included in an ATM UNI message, wherein 1, ..., 8 at the top represent bits, and 1, 2, 3 at the right side. , 4,5,6, ... represent octets (bytes).

In FIG. 6, the first octet is an information element identifier, and information elements are classified as shown in Table 6 according to the value. The present invention detects the received narrowband bearer capability information element. Since the information element identifier (IE Id.) Of the first octet is 00000100b, that is, the narrowband bearer capability information element identifier (NBC IE Id.) Is checked.

The narrowband bearer capability information element (NBC IE) is intended to indicate the required circuit mode N-ISDN bearer service provided by the network, which contains only the information used by the network. NBC) is clearly transmitted over B-ISDN.

Also, in the second octet, bit 8 is 1b as an extension, bits 7 and 6 are coding standards (CS), and bits 5 to 1 are information element command fields (IE Instruction Fields).

Herein, the coding standard (CS) is classified into four types according to bits 7 and 6 of the second octet. An ITU-T standard for 00b, an ISO / IED standard for 01b, and a national standard for 10b. 11b indicates a defined standard.

Bit 5 of the information element command field is a flag, 0b means that the information element command field is not important, and 1b means that an explicit command follows.

Bit 4 of the information element command field is a reserved bit, which is used to indicate a pass along request.

In addition, in the information element command field, bits 3 to 1 indicate an information element action indicator (IE Action Indicator), for example, 000b indicates a clear call, and 001b indicates a Discard and Proceed 010b. (Discard, Proceed and Report Status), 101b (Discard and Ignore), and 110b (Discard message, and repost status).

The third and fourth octets indicate Length of the Narrowband Bearer Capability (L).

Bit 8 of the fifth octet is 1b as an extension, bits 7 to 6 of the fifth octet are the same as the coding standard (CS) of the second octet as a coding standard, and bit 5 of the fifth octet Bits 1 to 1 are Information Transfer Capability (ITC) information, and when the bit value is 00000b, it indicates information on speech, and when it is 01000b, it indicates unrestricted digital information. Indicates limited digital information, 3.1kHz audio information for 10000b, 7kHz audio information for 10001b, and video information for 11000b.

Bit 8 of the sixth octet is 1b or 0b as an extension, and bits 7 to 6 of the sixth octet are transfer mode bits (TM), and if the bit value is 00b, circuit mode is selected. In case of 10b, the packet mode is shown, and bit 5 to bit 1 of the sixth octet are information transfer rate (ITR) information, and if the bit value is 00000b, the packet mode packet is used. code used for mode calls), 10000b for 64 kbit / s in circuit mode, 10001b for 2 * 64 kbit / s in circuit mode, and 10011b for 384 in circuit mode. In the case of 10101b, it represents 1536 kbit / s in circuit mode, and in case of 10111b, it represents 1920 kbit / s in circuit mode.

Bit 8 of the 6th octet is 1b or 0b as an extension, and bits 7 to 5 of the 6th octet represent a structure bit, which indicates a default value when the bit value is 000b. If this structure is omitted or a structure bit corresponding to bits 7 to 5 of the 6th octet is coded 000b, the structure characteristic value is shown in Table 7 below.

Subsequently, when the structure bits corresponding to bits 7 to 5 of the octet 6a are 001b, this indicates an 8 kHz integrity, and the information rate bit of the sixth octet is 2 * 64 kbit /. When set to s, an 8 kHz integrity with limited differential time delay (RDTD) is provided, and the structure bits corresponding to bits 7 to 5 of the 6th octet are 100b. The case indicates service data unit integrity, and the case 111b indicates that it is not structured. If the configuration bit corresponding to bits 4 to 3 of the 6th octet is 00b, this indicates a point-to-point shape. If the 6th octet is omitted, point-to-point is indicated. to-point). In addition, if the establishment bit corresponding to bits 2 to bit 1 of the 6th octet is 00b, it means that there is a demand. If the 6th octet is omitted, the establishment method has a request. It is estimated.

Bit 6 of the 6th octet is 1b as an extension, bits 7 to 6 of the 6b octet are symmetry bits, and when the bit value is 00b, it indicates bidirectional symmetric. Bits 5 through 1 of the 6b octet are information transfer rate (ITR) bits from the destination to the origin, and if the 6b octet is omitted, the bearer capability is determined in the 6a octet. If the sixth octet is bidirectionally symmetric at the specified rate, then the sixth b octet's information rate is directed from the origin to the destination.

Bit 8 of the seventh octet is 1b or 0b as an extension, bits 7 to bit 6 of the seventh octet are 01b, which is a bit value representing a Layer 1 identifier, and bits 5 to bit 1 of the seventh octet are User Information Layer 1 Protocol (UILIP), if its bit value is 00001b, it conforms to CCITT standard rate adaptation V.110 / X.30, which is the 7th octet and optionally the 7b octet, Means that the 7c octet and the 7d octet are present, and even if the bit value is 00010b, it is in accordance with the recommended G.711 μ-law (10), and in the case of 00100b, the recommendation G.711 A-law [10] In accordance with Recommendation G.721 [11] 32 kbit / s ADPCM and Recommendation I.460 for 00100b, and Recommendations G.722 [12] and G.725 [35] 7KHz audio for 00101b. In accordance with Recommendation H.261 [B] for 384 kbit / s video, and in case of 00111b non-CCITT standard rate adaptation. Octets and optionally 7b octets, 7c octets, and 7d octets, and in the case of 01000b, is in accordance with CCITT standard rate adaptation V.120 [9], which corresponds to the 7a and 7b octets, Optionally, there is a 7c octet and a 7d octet, and in the case of 01001b, it is according to CCITT standard rate adaptation V.31 [14].

In the case where the seventh octet is omitted, the transmission mode is the circuit mode, the information transmission capability (ITC) is not limited digital information or limited digital information, and the user information layer 1 protocol (UILIP) is not identified in the network. to be. In the case where the transmission mode is the packet mode, the seventh octet is omitted.

Bit 8 of the 7a octet is 1b or 0b as an extension, and bit 7 of the 7a octet is a synchronous and asynchronous (S / A) bit. When the bit value is 0b, it represents synchronous (S). , 1b, indicates asynchronous (A).

As the bit negotiation bit (Negotiation) of the seventh octet, when the bit value is 0b, in-band negotiation is impossible, and in the case of 1b, in-band negotiation is possible. In addition, bits 5 through 1 of octet 7a are User Rate (UR) bits. If the bit value is 00000b, the user rate is indicated by the E-bits specified in Recommendation I.460 [15]. For 00001b, follow 0.6 kbit / s Recommendations V.6 and X.1; for 00010b, follow 1.2 kbit / s Recommendation V.6; for 00011b, 2.4 kbit / s Recommendations V.6 and X.1. According to Recommendation 1, 3.6 kbit / s Recommendation V.6 for 00100b; 4.8 kbit / s Recommendations V.6 and X.1 for 00101b; 7.2 kbit / s Recommendation V.6 for 00110b. Per 00111b for 8 kbit / s Recommendation I.460, for 01000b for 9.6 kbit / s Recommendations V.6 and X.1, for 01001b for 14.4 kbit / s Recommendation V.6 For 01010b, 16 kbit / s Recommendation I.460; for 01010b; 19.2 Recommendation V.6; for 01100b; 32 kbit / s Recommendation I.460; for 01110b; 48 kbit / s Recommendations V.6 and X.1, in accordance with 56 kbit / s Recommendation V.6 for 01111b, 0.1345 kbit / s Recommendation X.1 for 10101b, and 0.100 kbits / s Recommendations for 10110b. According to X.1, in the case of 10111b, 0.075 / 1.2 kbit / s recommendation V.6 and X.1 indicate the transmission rate in the forward direction of the call; in the case of 11000b, 1.2 / 0.075 kbit / s recommendation V.6 And in accordance with X.1, which indicates the transmission rate in the backward direction of the call, in the case of 11001b, in accordance with 0.050 kbit / s Recommendations V.6 and X.1; in the case of 11010b, 0.075 kbit / s Recommendations V.6 and X According to .1, 0.110 kbit / s for 11011b V.6 and X.1; for 11100b, 0.150 kbit / s in accordance with Recommendations V.6 and X.1; and 0.200 kbit / s for 11101b. In accordance with V.6 and X.1, in accordance with Recommendation 0.300 kbit / s for 11110b and in accordance with Recommendation V.6 and X.1 for 11111b, in accordance with 12 kbit / s Recommendation V.6.

The 7b octet depends on whether it is a V.110 / X.30 rate adaptation or a V.120 rate adaptation.

Referring first to the 7b octet for V.110 / X.30 rate adaptation, bit 8 of the 7b octet is 0b or 1b as an extension, and bits 7 to 6 of the 7b octet are the intermadiate rate (IR). As a bit, it is not used when the bit value is 00b, the adjustment rate (IR) is 8 kbit / s in case of 01b, the adjustment rate (IR) is 16 kbit / s in case of 10b, and the adjustment rate (IR in case of 11b). ) Is 32 kbit / s. Bit 5 of octet 7b is a Network Independent Clock on Tx (NT) bit. If the bit value is 0b, it is not required to send data having a network independent clock (NIC). In that case it is required to send data with a network independent clock (NIC). Bit 4 of octet 7b is a Network Independent Clock on Rx (NR) bit. If the bit value is 0b, data having a network independent clock (NIC) cannot be received. Receive data with an independent clock (NIC). Bit 3 of the 7b octet is a flow control on Tx (FCT) bit. If the bit value is 0b, it is not required to send data having a flow control mechanism. It is required to send data with. Bit 2 of the 7th octet is a flow control on Rx (FCR) bit. If the bit value is 0b, the data having the flow control mechanism can be received. If the bit is 1b, the data has the flow control mechanism. Can be received.

Bit 1 of the 7b octet is a spare, which is 0b.

Subsequently, referring to the 7b octet for V.120 rate adaptation, bit 8 of the 7b octet is 0b or 1b as an extension, and bit 7 of the 7b octet is a header / non-header (H / NH: Heater / No Header). Bit, the rate adaptation header is not included when the bit value is 0b, and the rate adaptation header is included when the bit value is 1b.

Bit 6 of the seventh octet is a Multiple Frame establishment Support in Data Link (MFS) bit. If the bit value is 0b, the multiple frame setting is not supported. The frame setting is supported. Bit 5 of the seventh octet is an operation mode bit, and when the bit value is 0b, it indicates a bit transparent mode of operation, and when it is 1b, a protocol sensitive mode of operation is performed. )). Bit 4 of octet 7b is a Logical Link identifier Negotiation (LN) bit. If the bit value is 0b, the default is Logical Link identifier (LLI) = 256. . Bit 3 of octet 7b is the assignor / assignee (A / A: Assignor / Assignee) bit. If the bit value is 0b, it indicates that the origin of the message is the default assignee. Indicates that this is an assignor only.

Bit 2 of octet 7b is an in-band / out-band bit. If the bit value is 0b, the negotiation is performed together with a user information message on a temporary signal connection. The compromise is performed in the band using logical link zero, and bit 1 of octet 7b is a spare, 0b.

Bit 8 of the 7c octet is 0b or 1b as an extension, and bits 7 to 6 of the 7c octet represent the number of stop bits (NSB), and are not used when the bit value is 00b. , 01b indicates 1 bit, 10b indicates 1.5 bits, and 11b indicates 2 bits. Bits 5 to 4 of the 7th octet indicate the number of data bits (NDB) excluding parity bits, and are not used when the bit value is 00b, and indicate 5 bits when 01b. 10b indicates 7 bits, and 11b indicates 8 bits. Bits 3 through 1 of the 7th octet are bits indicating parity information. If the bit value is 000b, it indicates odd number, and if it is 010b, it indicates even number. There is no parity information (None), and 0 is 100b, and 1 is 101b.

Bit 8 of the 7th octet is 1b as an extension, and bit 7 of the 7th octet indicates a duplex mode (DM). When the bit value is 0b, it indicates half duplex and 1b. The case represents full duplex. Bits 6 through 1 of the 7th octet are modem type (MT) bits, and are coded according to network specification rules.

Bit 8 of the eighth octet is 1b as an extension, bits 7 through 6 of the eighth octet are layer 2 indentifier bits, and its bit value is 10b, and bits 5 through 1 of the eighth octet are user information. User Information Layer 2 Protocol (UIL2P) bits. If the bit value is 00010b, follow Recommendation Q.921 (I.441); if it is 00110b, follow Recommendation X25 and the link layer. If the transmission mode is packet mode, the eighth octet exists, and if the user information layer 2 protocol (UIL2P) is identified in the network, then the eighth octet exists.

Finally, looking at the ninth octet, bit 8 of the ninth octet is 1b as an extension, and bits 7 to 6 of the ninth octet are layer 3 identifier bits, whose bit value is 11b, and the ninth octet. Bits 5 through 1 of the octet are User Information Layer 3 Protocol (UIL3P) bits, which are in accordance with Recommendation Q.921 (I.451) if the bit value is 00010b and 00110b. Follow Recommendation X.25, Packet Layer. If the User Information Layer 3 protocol (UIL3P) is identified on the network, the ninth octet is present.

7 is a block diagram showing the configuration of hardware for performing the method according to the present invention. The hardware for performing the method of the present invention includes a message generation unit 10 of a higher layer that generates a message for call and connection. ; Receives the message generated by the message generator 10 through the CPU bus, performs the function of mapping the service signals to the effective load space of the ATM cell, performs the function related to the ATM cell header, and transmits the ATM cells bit The ATM card 20 transfers heat by heat.

Here, the message generator 10 is implemented as a computer system including a host CPU 11 and a storage 12, wherein the storage 12 is a DRAM for storing messages. 12-1), a DRAM controller 12-2 for controlling the DRAM 12-1, a ROM 12-3 for storing a call processing program, and the like, and storing information that is not desired to be destroyed when the power is turned off. It consists of a nonvolatile RAM 12-4.

The ATM card 20 converts a packet memory 21 for temporarily storing an ATM cell, a control memory 22 for storing a control program for making data into a required form, and transfers data into an ATM cell form. Conversely, it consists of an AAL unit 23 for extracting only data from an ATM cell, an ATM cell header-related function, and an ATM layer and a physical layer unit 24 that transfer ATM cells into bit strings.

Next, operation of hardware for performing the method of the present invention will be described.

The host central processing unit 11 of the message generating unit 10 secures an area for generating a message in the DRAM 12-1 of the storage unit 12 while performing a predetermined sequence according to a request of an application or a client. A message is generated in the area according to a predetermined format.

The data input via the CPU bus is stored in the packet memory 21 of the ATM card 20, and the data is input to the AAL cutting unit 23-1 of the AAL unit 23 constituting the ATM card 20. The AAL recombination unit 23-2 of the AAL unit 23 constituting the ATM card 20 extracts only data from ATM cells input from the ATM layer and the physical layer unit 20. . At this time, the role of the packet memory 21 and the control memory 22 is necessary.

That is, the AAL layer makes user information of a higher layer into a protocol data unit (PDU), and also performs a function of cutting a protocol data unit to form a user information section of an ATM cell and recombining it.

Here, the AAL unit 923 of the ATM card 20 has an AAL5 function for Q.2931, and AAL-3 / 4 for connection and connectionless data communication complies with the protocol and is suitable for high speed data communication. This raises the need for AAL5, which is similar to AAL-3 / 4 but with a greatly simplified functionality.

That is, AAL has sublayers of segmentation and reassembly (SAR), common part convergence sublayer (CPCS), and service specific convergence sublayer (SSCS), and the service mode is divided into message mode and stream mode. There is a non-delivery method of delivery. The difference from AAL-3 / 4 is that multiplexing is not supported at first, and if multiplexing is in the AAL layer, this happens in SSCS.

Meanwhile, the ATM layer and the physical layer unit 20 of the ATM card 20 are divided into an ATM layer and a physical layer. Looking at each function, the ATM layer utilizes a general flow control interval (GEC) to interface only a user (UNI). Control access and information flow, and translate virtual path identification number (VPI) / virtual channel identification number (VCI) to connect with service access points (SAP), and multiplex and demultiplex cells Let's do it. In addition, it handles payload type (PT) or cell abandonment rank (CLP) sections and generates and extracts headers of ATM cells.

In addition, the physical layer performs separation of cell rates, generation and confirmation of header error control bytes, detection of cell boundary points, and generation and confirmation of transmission frames in the case of transmission based on synchronous digital hierarchy (SDH). It is also responsible for the final transmission over optical fiber or coaxial cable.

8 is a sequence of detecting the received narrowband bearer capability information elements among the information elements included in the call processing related message according to the present invention. Referring to the method of the present invention, the received information elements are received in step S1. Is stored in the memory area m [.], And in the second step S2, it is determined whether the information element identifier stored in the memory area m [0] is the narrowband bearer capability information element identifier NBC IE Id. In the third step S3, as a result of the determination in the second step S2, the information element identifier IE Id. Stored in the memory area m [0] is determined as the narrowband bearer capability information element identifier (I). NBC IE Id.), Coding standard (CS),. Detects the bit value corresponding to the flag and the information element action indicator (IE AI), and detects the bit value corresponding to the length L of the NBC content in the fourth step S4. In the fifth step S5, the bit value corresponding to the information transmission capability ICT is detected, and in the sixth step S6, the bit value corresponding to the transmission mode TM and the information transmission rate ITR is detected. In the seventh step S7, bit values corresponding to the structure, configuration, and establishment are detected. In the eighth step S8, the bit values corresponding to symmetry and information transmission rate (ITR) are detected. Detects a bit value, and detects a bit value corresponding to the user information layer 1 protocol (UILIP) in the ninth step (S9), user information detected in the ninth step (S9) in the tenth step (S10) Non-corresponding to synchronous (S) / asynchronous (A) bits, negotiation bits, and user rate (UR) according to Layer 1 protocol (UILIP) Value is detected, and in the eleventh step S11, in accordance with the user information layer 1 protocol UILIP detected in the ninth step S9, the adjustment ratio IR, the originating network independent clock NT, and the receiving network independent Clock (NR), Originating Flow Control (FCT), Receiving Flow Control (FCR), or Header / Beheader (H / NH), Multiple Frame Support (MFS), Mode, Logical Link Identification Negotiation (LN) ), The bit values corresponding to the assignor / quantizer (A / A) and the in-band / out-band negotiation (ION) bits are detected. In the twelfth step S12, the number of maintenance bits (NSB) and the number of data bits (NDB) are detected. And detecting a bit value corresponding to parity, and detecting a bit value corresponding to a dual mode (DM) and a modem type (MT) bit in a thirteenth step (S13), and a user in a fourteenth step (S14). A bit value corresponding to the information layer 2 protocol UIL2P is detected, and in step 15, a bit value corresponding to the user information layer 3 protocol UIL2P is detected.

Referring to FIG. 8, the steps of the present invention will be described in detail.

In the first step S1, a memory area m [.] Is secured in an array form to store the received information element, and the secured memory area m [.] Is n from the first octet. Up to the first octet, each is represented by a zero memory area-an nth memory area m [0], m [1], ..., m [n].

In the second step S2, the bit value of the zero memory area m [0] corresponding to the information element identifier IEId of the first octet (shown in FIG. 6) is the narrowband bearer capability information element identifier. Determine whether it is (NBC IE Id.). If the bit value of the information element identifier (IE Id.) Is 00000100b, refer to Table 6), since the bit value corresponding to the narrowband bearer capability information element identifier (NBC IE Id.) Is represented, the following third step (S3). If other bit values correspond to other information elements, the process branches to processing for other information elements (not shown in FIG. 8) without going through the steps of the present invention.

In the third step S3, the coding standard CS corresponding to the second octet of the format of the information element shown in FIG. 6 and the flag and information element action indicator AI of the information element command field are shown. Bit values are detected. In detail, the steps of detecting each bit value are described in detail. In step 3-1, a first memory area m is detected to detect bits 7 and 6 corresponding to coding standard (CS) bits. Performs a logical AND on the bit value stored in [1]) and 01100000b. In step S3-2, a first memory area is used to detect bit 5 corresponding to a flag bit. Logical AND is performed on the bit value stored in (m [1]) and 00010000b. In step S3-3, bits 3 and 2 corresponding to the information element action indicator bits AI are performed. And a logical product of 00000111b with the bit value stored in the first memory area m [1] to detect bit 1.

In the fourth step S4, the OR is performed on the bit value obtained by shifting the bit value stored in the second memory area m [2] by 8 bits to the left and the bit value stored in the third memory area m [3]. The length of the narrowband bearer capability content is determined by

In step 5-1 (S5-1) of the fifth stage (S5), the variable n value is set to 4. The reason for this setting is the bit value of the fourth memory area m [4], that is, the first value. In order to detect the bit value of the fifth octet shown in FIG. 6, in step 5-2 (S5-2), the bit value of bits 5 to 1 corresponding to the information transfer capability (ITC) bit is detected. The AND is performed on the bit value designated in the four memory areas m [4] and 00011111b.

In step 6-1 (S6-1) of the sixth step (S6), 1 is added to the variable n value of the fifth step (S5), and the resultant value is set to a new variable n value, that is, 5; The reason is to detect a bit value corresponding to the sixth octet of the fifth memory area shown in FIG. In step 6-2, the bit value stored in the fifth memory area m [5] and 01100000b are used to detect the bit value of bit 7 to bit 6 corresponding to the transfer mode (TM) bit. To the fifth memory area m [5] in order to detect a bit value of bit 5 to bit 1 corresponding to an information rate (ITR) bit in step S6-3. The AND is performed on the stored bit value and 00011111b.

In the seventh step S7-1 of the seventh step S7, a comparison is made to determine whether the bit value stored in the fifth memory area m [5] is smaller than 10000000b. If it is small, the process goes to the next step 7-2 (S7-2). In step 7-2, after adding 1 to the variable n value of the sixth step S6, the result value, that is, 6 is set as the new variable n value. In step S7-3, a logical AND operation is performed on the bit value of the sixth memory area m [6] corresponding to the sixth octet and 01110000b to bits 7 to 6 bits of the sixth octet. Detects a structure bit value corresponding to 5 and performs a logical AND on the bit value of the sixth memory area m [6] corresponding to the sixth octet and 00001100b, thereby performing the bit of the sixth octet. Detects a configuration bit value corresponding to 4 to bit 3, and performs a logical AND on the bit value of the sixth memory area m [6] corresponding to the sixth octet and 00000011b. Detect a setup bit value corresponding to bits 2 through 1 of an octet.

In the eighth step S8-1 of the eighth step S8, a comparison is made to determine whether the bit value stored in the sixth memory area m [6] is smaller than 10000000b. The process proceeds to S9 and, if small, the process goes to the next step 8-2 (S8-2). In the eighth step (S8-2), 1 is added to the variable n value of the seventh step (S7), and the result value, that is, seven is set as the new variable value. In step S8-3, a logical product AND of the bit value of the seventh memory area m [7] corresponding to the sixth octet and 01100000b is performed to perform bits 7 to bit of the sixth octet. Detects a symmetry bit value corresponding to 6 and performs a logical AND on the bit value of the seventh memory area m [7] corresponding to the sixth octet and 00011111b, thereby performing the bit of the sixth octet A bit rate (1TR) bit value of information from the destination corresponding to 5 to bit 1 to the source is detected.

In step 9-1 (S9-1) of the ninth step S9, after adding 1 to the variable n value of the sixth step S6, the seventh step S7, or the eighth step S8, The result, i.e., 6, 7, or 8, is set to the new variable n value. In this case, it is assumed that the new variable n is set to 8 in step 9-1. In step 9-2, the bit value of the eighth memory area m [8] corresponding to the seventh octet and 00011111b are determined. The AND is performed to detect a user information layer 1 protocol (UILIP) bit value corresponding to bits 5 to bit 1 of the seventh octet.

In step 10-1 (S10-1) of the tenth step (S10), a user information layer 1 protocol (UILIP) bit value of the eighth memory area m [8] detected in the ninth step (S9). If it is determined that this corresponds to V.110 / X30 or V.120, and if it does not correspond to V.110 / X30 or V.120, the process proceeds to step 14 (S14) and V.110 / X30 or V.120. If it corresponds to 120, the process proceeds to the next step 10-2 (S10-2). In step 10-2 (S10-2), 1 is added to the variable n value of the ninth step S9, and the result value, that is, 9 is set as a new variable value.

In step S10-3, a logical AND operation is performed on the bit value of the ninth memory area m [9] corresponding to the seventh octet and 01000000b to bit 7 of the octet of the seventh octet. The corresponding sync / asynchronous (S / A) bit value is detected, and the logical product (AND) is performed on the bit value of the ninth memory area m [9] corresponding to the seventh octet and 00100000b to the seventh octet Detects a negotiation bit value corresponding to bit 6 of the second bit and performs a logical AND on the bit value of the ninth memory area m [9] corresponding to the seventh octet and 0001 1111b. The user rate (UR) bit value corresponding to bit 5 to bit 1 of an octet is detected.

In step 11-1 (S11-1) of the eleventh step S11, after adding 1 to the variable n value of the tenth step, the result value, that is, 10 is set as a new variable n value, In step -2 (S11-2), it is determined whether the bit value of the user information layer 1 protocol bit of the eighth memory area m [8] detected in the ninth step S9 corresponds to V.110 / X30, If not, the process proceeds to the next step 11-4 (S11-4), and if applicable, the process goes to the next step 11-3 (S11-3). In step S11-3, a logical product AND of the bit value of the tenth memory area m [10] corresponding to the seventh octet and 01100000b is performed to perform bits 7 to bit of the seventh octet. Detects an adjustment rate 1R bit value corresponding to 6 and performs a logical AND on the bit value of the tenth memory area m [10] corresponding to the seventh octet and 00010000b, thereby performing the bit of the seventh octet. Detects the originating network independent clock bit value corresponding to 5, and performs a logical AND on the bit value of the tenth memory area m [10] corresponding to the seventh octet and 00001000b to perform the seventh octet Detecting the reception side network independent clock bit value corresponding to bit 4, and performing a logical AND on the bit value of the tenth memory area m [10] corresponding to the seventh octet and 00000100b, the seventh octet Detects the source-side flow control (FCT) bit value corresponding to bit 3 of < RTI ID = 0.0 >, and < / RTI > The AND is performed to detect a reception flow control (FCR) bit value corresponding to bit 2 of the seventh octet. In operation S11-4, a logical AND operation is performed on the bit value of the tenth memory area m [10] corresponding to the seventh octet and 0100 0000b to bit 7 of the seventh octet. The header / non-header (H / NH) bit value is detected, and the logical product AND is performed on the bit value of the tenth memory area m [10] corresponding to the seventh octet and 00100000b to perform the seventh b. Detects the MFS bit value corresponding to bit 6 of the octet and performs a logical AND on the bit value of the tenth memory area m [10] corresponding to the seventh octet and 00010000b. Detects an operation mode bit value corresponding to bit 5 of the seventh octet and performs a logical AND on the bit value of the tenth memory area m [10] corresponding to the seventh octet and 00001000b. Detects the logical link identifier compromise (LN) bit value corresponding to bit 4 of the 7b octet, and logically multiplies the bit value of the tenth memory area m [10] corresponding to the seventh octet by 00000100b. AND) to detect the assignor / quantizer (A / A) bit value corresponding to bit 3 of the 7th octet, and to the bit value of the tenth memory area (m [10]) corresponding to the 7th octet and 00000010b. An AND is performed to detect an in-band / out-band compromise bit value corresponding to bit 2 of the seventh octet.

In step 12-1 (S12-1) of the twelfth step S12, after adding 1 to the variable n value of the eleventh step S11, the result value, that is, 11 is set as a new variable value, In step 12-2, a stop bit corresponding to bits 7 to 6 of the 7c octet is performed by performing an AND on the bit value of the eleventh memory area m [11] corresponding to the 7c octet and 01100000b. Detects the number (NSB) bit value and performs AND on the bit value of the eleventh memory area m [11] corresponding to the seventh octet and 00011000b to bits 5 to 4 of the seventh octet. Detects the corresponding data bit number (NDB) bit value and performs logical multiplication on the bit value of the eleventh memory area m [11] corresponding to the seventh octet and 00000111b to bits 3 to 1 of the seventh octet. The corresponding parity bit value is detected.

In step 13-1 (S13-1) of the thirteenth step (S13), 1 is added to the variable n value of the twelfth step S12, and the resultant value is set to 12 as a new variable n value. In operation S13-2, a logical AND operation is performed on the bit value of the twelfth memory area m [12] corresponding to the seventh octet and 01000000b to bit 7 of the seventh octet. Bit 7 of the 7th octet is detected by performing a logical AND on the bit value of the twelfth memory area m [12] corresponding to the 7th octet and 00111111b. Detects a modem type (MT) bit value corresponding to the first through the second.

In step 14-1 (S14-1) of the fourteenth step S14, 1 is added to the variable n value of the thirteenth step S13, and the result value, that is, 13 is set as a new variable n value. In operation 14-2, a logical product AND of the bit value of the thirteenth memory area m [13] corresponding to the eighth octet and 00011111b is performed to correspond to bits 5 to bit 1 of the eighth octet. Detects a user information layer 2 protocol (UIL2P) bit value.

Finally, in step 15-1 (S15-1) of the fifteenth step (S15), 1 is added to the variable n value of the fourteenth step (S14), and the result value, that is, 14 is the new variable n value. In step 15-2, in operation S15-2, the AND of the bit value of the fourteenth memory area m [14] corresponding to the ninth octet and 00011111b is performed, thereby performing a bit of the ninth octet. Detects a user information layer 3 protocol (UIL3P) bit value corresponding to 5 to bit 1.

As a result, by sequentially operating the above steps, the received narrowband bearer capability information element is detected among the information elements included in the call processing related message in the ATM user interface (UNI).

As described above, according to the present invention, since the Q.2931 protocol can be applied to an ATM user network interface (UNI), it is possible to easily set up a channel connection for transmitting data by ATM.

Claims (3)

A method for detecting an information element included in a message of a received user network interface for establishing a call in accordance with an ATM method from one terminal connected to an ATM network to another terminal connected to the above word, comprising: a received information element memory area A first step (S1) to store in the; A second step (S2) of determining whether the information element identifier stored in the memory area is a narrowband bearer capability information element identifier; A third value for detecting a bit value corresponding to a coding standard, a flag, and an information element action indicator when the information element identifier stored in the memory area is a narrowband bearer capability information element identifier as a result of the determination in the second step S2; Step S3; Detecting a bit value corresponding to the length of the narrowband bearer capability content (S4); Detecting a bit value corresponding to the information transmission capability (S5); Detecting a bit value corresponding to a transmission mode and an information transmission rate (S6); A seventh step S7 of detecting a bit value corresponding to the structure, form, and setting; An eighth step S8 of detecting bit values corresponding to symmetry and information rate; Detecting a bit value corresponding to the user information layer 1 protocol (S9); A tenth step (S10) of detecting a bit value corresponding to a synchronous / asynchronous bit, a compromise bit, and a user rate according to the user information layer 1 protocol detected in the ninth step (S9); According to the user information layer 1 protocol detected in the ninth step (S9), the adjustment rate, the source network independent clock, the receiving network independent clock, the calling side flow control and the receiving side flow control or header / non-header, multiple frame support, An eleventh step (S11) of detecting bit values corresponding to mode, logical link identification compromise, assigner / quantizer, and in-band / out-band negotiation bits; A twelfth step (S12) of detecting bit values corresponding to the number of stop bits, the number of data bits, and the parity; Detecting a bit value corresponding to a dual mode and a modem type bit (S13); Detecting a bit value corresponding to the user information layer 2 protocol (S14); And a fifteenth step of detecting a bit value corresponding to the user information layer 3 protocol. The method of claim 1, wherein the third step (S3) comprises: a step 3-1 (S3-1) of detecting a coding standard by performing an AND operation on the bit value stored in the first memory area and 01100000b; Step 3-2 (S3-2) of detecting a flag by performing an AND operation on the bit value stored in the first memory area and 00010000b; Method 3 and step 3-3 (S3-3) of detecting an information element action indicator by performing a logical multiplication on the bit value stored in the first memory area and 0000011b. . 2. The method of claim 1, wherein in the fourth step S4, a narrow band is performed by performing an OR between the bit value of the bit value stored in the second memory area by 8 bits and the bit value stored in the third memory area. A call and access control method in an ATM user network interface, comprising obtaining a length of a bearer capability content.