KR970008679B1 - Method for determining and adding pad variable in broadband communication type5 - Google Patents

Abstract

A method for determining and adding a pad parameter in a wide band telecommunication type 5. The pad parameter is determined by a present CPCS data, so that the pad is easily added at CPCS(Common Part Convergence Sublayer) area of the AAL(Asynchronous Transfer Mode Adaptation Layer) of the transmitter.

Description

Pad Variable Determination and Pad Addition Method in Broadband Communication Type 5

1 is a schematic diagram of a broadband communication system in which a method for determining pad parameters and adding pads is performed according to the present invention.

2A to 2C are diagrams showing the configuration of transmission data of a common part convergence sublayer (CPCS) used in the pad adding method according to the present invention.

3A to 3D are flowcharts illustrating a pad adding method according to the present invention.

* Explanation of symbols for main parts of the drawings

121,321: higher layer processor 123: CPCS layer processor

127: ATM layer processor 130: physical layer processor

140,340: Interface processor for the first and second ATM communication

150, 350: terminal 160, 360: first and second data transmission block

200: ATM relay network

The present invention relates to a method of adding a pad in an asynchronous transfer mode adaptation layer (ALL) of broadband communication, and in particular, a common part of a transmitting side by adaptively changing a pad variable according to transmission data. A pad variable determination and pad addition method in a wideband communication type 5 which enables easy addition of pads to a common part convergence sublayer (CPCS) region.

BISDN was formed under the influence of optical communication standardization while expanding to accommodate various broadband signals by taking advantage of the basic purpose of ISDN standardization. Asynchronous Transfer Mode (ATM) communication method. In other words, ATM communication is a special type of jacket-type delivery using asynchronous time division multiplexing (ATDM) as a communication method for implementing BISDN. BISDN has a wide spectrum of continuity ranging from narrowband services such as remote metering, data terminal, telephone, and facsimile to wideband services such as video telephony, video conferencing, high speed data transmission and video signal transmission. Integrating both real-time signals and clustered data signals. Therefore, there is a need for an effective processing method that can handle such various services in common, and the solution is ATM communication.

Using ATM communication, the following advantages can be obtained. That is, a highly flexible network connection is possible, and variable bandwidth allocation is possible. In addition, the ATM communication method is defined independently of the transport of the physical layer, and can be transmitted through various physical media and transport networks.

The ATM communication method can be said to be a mixture of the conventional line mode digital communication method and packet mode communication method. In other words, the ATM communication method is close to the packet communication method in that an ATM cell which has been unified so that various service signals have the same appearance as the basic transmission means is close to the packet communication method. The difference is that they can be treated equally. In addition, the packet method was generally used locally in a local area network (LAN). However, since the ATM communication method is used for a huge notary network, there are various difficulties in addressing, accessing and controlling flow, exchange, and transmission. On the other hand, in comparison with the circuit mode communication method, in the channel mode, after allocating a channel for each service, the information signal is transmitted as a continuous bit string through this channel. However, in the ATM communication method, the information signal is cut and put into an ATM cell. There is a fundamental difference in delivering through channels. Accordingly, several new problems arise in connection establishment, signal processing, data transmission, and exchange.

In the present invention, in realizing the ATM communication scheme, among the problems raised as described above, in particular, a pad variable is first obtained in order to add a pad in the data transmission at the transmitting side, that is, the AAL layer at the transmitting side. It relates to the technique of the pad portion. The pad technique refers to a process of adding a meaningless symbol (eg, "0") at the end of a data area so as to conform to the data format. However, in the broadband communication, the pad addition technique in the ALL layer is a type of the ALL layer in the ATM communication system. Since the recommendations from 5 are currently disclosed, the devices and algorithms that embody them are based on such recommendations. Development has been required.

Accordingly, an object of the present invention is to meet the above-described requirements, and an object of the present invention is to determine a pad variable according to transmission data and to add a pad to a CPCS region in a transmitting AAL layer according to the determined pad variable. The pad variable determination and pad addition in 5 provide a method.

The object of the present invention described above is to transmit data in units of a predetermined partition among all the data to be transmitted, and to sequentially transmit data of a predetermined amount first among the predetermined partition units, and to transmit all of the predetermined data amounts. After that, the preset area is secured so that trailer information is added and transmitted, and the transmission-side asynchronous delivery mode adaptation layer (AAL) processor according to the transmitted data (common part convergence sublayer (CPCS) data). A pad variable is determined to add a pad to the CPCS region of the pad, and a pad is added according to the determined pad variable. The pad variable includes: a first variable representing a size of previously transmitted data among the total transmission data to be transmitted; a pad and a first variable for initializing a third variable indicating whether the portion of data to be transmitted is the last portion of all the data to be transmitted; And a second step of determining whether the first variable value is less than or equal to the total data to be transmitted and whether or not the third variable value is the last part after the first step, and the whole to be transmitted in the second step. A second step of determining whether a difference (residual data) value between the data and the first variable value is smaller than the predetermined division area unit, and whether or not the third variable value is the last part or the second step; In the case where the difference (residual data) between the total data to be transmitted and the value of the first variable is smaller than the predetermined division area unit and indicates that the value of the third variable is not the last part, the residual data and the Calculating a residual value and a quotient value by calculating data of a predetermined amount in a predetermined partition unit, and determining first and second pad variables in response to the measured residual value and the quotient value. For the first pad variable determined in step 3 and the third step, the first pad unit measured using the preset partition area unit and the measured residual value is continuously and sequentially numbered by the number corresponding to the area. And a fourth step of sequentially and sequentially adding pads to the second pad variable determined in the third step by the number corresponding to the area of the second pad unit excluding the trailer information in the size of the preset partition unit. It can achieve by providing.

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

FIG. 1 is a block diagram showing a schematic connection diagram of an ATM communication system in which a pad variable determination and pad addition method in the broadband communication type 5 according to the present invention are executed. FIG. 1 is a first data transmission block 160 and an ATM relay network. And a second data transmission block 360. The first and second data transmission blocks 160 and 360 may include the first and second ATM communication interface processors 140 and 150 for high performance and high efficiency data communication between the terminals 150 and 350 and the ATM relay network 200. 340. In addition, the first and second ATM communication interface processors 140 and 340 may include a physical layer processor 130, an ATM layer processor 127, an AAL layer processor 123, and a higher layer processor for systematic and flexible information transfer. 121) each.

In the description of the present invention, the first data transmission block 160 is called a transmission system, and the second data transmission block 360 is called a reception system. In the transmission direction, first, the upper layer processor 121 is for matching between the terminal 150 and the first ATM interface processor 140, and is pre-stored in a storage device (not shown) in the terminal 150. When transmitting data, it is responsible for controlling this interface processor such as reading it and delivering it to the AAL layer processor 123 which will be described later. As shown, the AAL layer processor 123 includes a buffer 124 that stores transmission data from the upper layer processor 121 for a predetermined time, a CPCS layer processor 125, and a SAR layer processor 126. The ATM layer processor 127 includes an overhead processor 128 for adding header information to the transmission data from the AAL layer processor 123, and a buffer 129 for storing such data and header information for a predetermined time. That is, the ATM layer processor 127 controls the general signal flow and is responsible for generating and extracting headers of the ATM cell.

On the other hand, the physical layer processor 130 is composed of a circuit for transmitting the transmission information received from the ATM layer processor 127 to the ATM relay network 200. That is, the physical layer processor 121 is composed of a transmission convergency (TC) sublayer and a physical medium sublayer processor (not shown). The former functions include separation of cell rates, generation of header error control bytes, and It is in charge of checking and detecting cell boundary points. In addition, when transmitting on the synchronous digital system, the transmission frame is generated and confirmed. And the latter is the final transmission step through optical fiber or coaxial cable. If the above-described first data transmission block 160 is a reception side instead of a transmission side, that is, when receiving the data transmitted from the second data transmission block 360, those skilled in the art will appreciate that the signal processing procedure It will be appreciated that this will be the reverse of the process described above.

The present invention relates to a method of adding a pad in the above-mentioned first and second data transmission blocks 160 and 360, namely, among the layer processors at the transmitting and receiving side, in particular, as described above, in the transmitting AAL layer processor 123. In the following description, only the pad variable determination and the pad addition method in the first data transmission block 160, particularly the CPCS layer processor 125 in the AAL layer processor 123, will be described in detail. A detailed description of the other layer on the side and the signal processing for the second data transmission block 300 will be omitted.

In the case where data is to be transmitted from the storage in the transmitting terminal 150 to the receiving terminal 340 via the ATM relay network 200, the AAL layer processor 123 is described in more detail above. CPCS layer processor 125 which stores the transmission information from 126 into buffer 124 and reads it if necessary into protocol data unit (PDU); Segmentation and Reassembly (SAR) sublayer processor 126 forming a user information section of an ATM cell.

Referring now to FIG. 2, FIG. 2 illustrates in detail the CPCS data structure representing the recommendations from AAL Type. 5 described above. One ATM cell is formed of a total of 53 octets as a header section of 5 octets (or bytes) and an information section of 48 octets. Transmission of data and trailer information in the CPCS information section (48 octets) always requires an area for allocating trailer information of 8 octets. Among the considerable amount of data to be transmitted, first, it is always 48 octets (0 to 47). After sequentially dividing and transmitting data units, trailer information should always be allocated in 8 octets (40 to 47) of the last remaining data. The additional work of 5 octets of header information is performed by the ATM layer processor 122.

On the other hand, the padding unit according to the present invention is composed of the unoccupied octets (0 to 39) in the above 48 octets (0 to 47) information intervals, that is, the data divided into predetermined units as described above. If all the data is transmitted and the data of the last area is less than 40 octets, for example, as shown in FIG. 2A, type AAL. In the 5 recommendation, since the data is contained within the 39 octet period (0 to 38), it is 8 octets. CPCS trailer information can be added and transmitted through the intervals 40 to 47. Therefore, the pad operation is performed only in one octet area (i.e., 39 octets), that is, "0" is added. In the case of FIG. 2B, data is filled in all 40 octet sections 0 to 39. In this case, pad work is not required. In the same case, when the transmission data exceeds 40 octets (0 to 39), the CPCS trailer area is not 8 octets. In such a case, according to the recommendation, the remaining area, that is, 7 octet areas (as shown) 41 to 47), and continue to the first region in a preset partition unit, that is, 40 octets (0 to 39), and the remaining 8 octets (40 to 47). In the following description, CPCS trailer information is allocated and transmitted in the same manner as described above.

Referring now to FIG. 3, FIG. 3 shows a flow chart according to a preferred embodiment of the method for determining pad parameters and adding pads in broadband communications of the present invention based on the recommendations described with reference to FIG. FIG. 3A illustrates the main processing control flow executed by the upper layer processor 121 described above to control the entire first ATM network interface processor 140.

First, after the program of the upper layer processor 121 is started in step S8, step S10 is performed, which is performed by the first ATM communication interface processor 140 to execute a method of determining a pad variable. Initializing the execution variables of the variable, Subtotal.data representing the size of the data already transmitted, and a variable for determining the number of cases for the PAD of the type as described with reference to FIG. pad) and variables indicating whether the data of the area to be transmitted are the last part are set to a state of "0". In the next step S12, it is determined whether the value of the above-mentioned variable (Subtotal data) is smaller than or equal to the value of the variable (Total data) indicating the total length of the data of the preset amount to be transmitted, Is "0", that is, it is not the last part of the preset amount of data, and if neither of them is established, that is, the value of the Subtotal data is less than or equal to the value of the Tota data, and the variable (Last). If it is determined that the value of data) is " 0 ", the process proceeds to block S13 where the main process control execution ends, and if it is discriminated against the above-described result, the process proceeds to the next step S14.

In step S14, after the step S12 is executed, the value of the total data of the data to be transmitted is subtracted from the total data value that has already been transmitted, and this subtracted value is subtracted. A variable size value indicating the size of data to be transmitted at one time, that is, the packet size defined in the embodiment according to the present invention (for example, in the embodiment of the present invention, one packet size is set to a size of 48 octets x 26). Is judged to be smaller or greater than < RTI ID = 0.0 >). ≪ / RTI > if the latter, the process proceeds to step S16. Step S16 is executed when the remaining data is not smaller than the above-mentioned one packet size AALSIZE as a result of the determination in step S14, as described above. In this case, the already transmitted data variable (Subtotal data) Subtract one packet size and reset it back to a new variable (Subtoatal data) value, and at the same time return to step S12 described above to allow the operation of the above steps to continue.

On the other hand, in step S18, as described above, when the residual data is smaller than one packet size (AALSIZE) as a result of the determination in step S14, in this case, the residual data subtracted above is used. Divide the remaining data by 48 octets to find the remainder. After dividing by 48 octets to obtain a quotient, the process proceeds to the next step S20.

Step S20 is a step of determining whether the quotient obtained in the above-described step S18 is less than or greater than 25, namely, which of the cases illustrated in FIGS. In order to judge the comparison, it is determined. In this case, if the quotient is less than 25, the process proceeds to step S22, and when the opposite is the case, the process proceeds to step S24. Step S22 determines whether the remainder is greater than or less than 40 secondly following the aforementioned step to obtain the pad variable pad as described above, and if the remainder is greater than 40, proceed to the next step S26. If it is the contrary, the process proceeds to step S28. In the same manner, after determining this in step S24, if it is the former, the process proceeds to step S30, and in the opposite case, proceeds to step S28.

Steps S26, S28, and S30 are steps of determining final pad variables according to the results determined in the above-described steps S22 and S24, respectively. After determining the variables with pads 2, 1 and 2, respectively, The process proceeds to steps S32 and S34, respectively. The variable values thus determined are transferred to the CPCS layer processor 125 to be described later, and the pad unit executes the operation. Step S32 is a case where the quotient is less than 25 as a result of the determination in step S20 described above. After determining the pad variable (that is, pads 1 and 2) in steps S26 and S28 described above, the transmission is now performed. When the last data is set to "1" indicating that the area of the data to be lasted is set to "1", the process proceeds to the next step S34, and the quotient of the above-described step S20 is not less than 25. Thereafter, after passing only the above-described process of steps S24 and S30 without the process of step S32, the process proceeds directly to step S34.

In step S34, a variable data value indicating the remaining data left so far is transmitted to the CPCS layer processor block 123 described above, and a variable dato value representing the data transmitted so far and After adding the left data value indicating the residual data, resetting it to the data variable transmitted again, that is, the new variable (Subtotal data), and returning it to the above-described step (S12) to repeat the program continuously. Make it work.

FIG. 3B illustrates an execution operation in the processor 123 that performs the CPCS layer processor in the first ATM communication interface processor 140 using the processing result in FIG. 3A described above. As shown, first, the execution of the CPCS layer processor 125 is started in step S42, and then the process proceeds to step S44 to receive the pad variables obtained from the main processor of the upper layer described above. After that, the process proceeds to the next step S46.

Step S46 is a step of determining whether the pad variable is "0" or not "0". The determination result is "0", and as shown, the process proceeds to step S60 described later and "0". If not, the process proceeds to the next step S48. In step S48, if the pad variable is not " 0 ", then it is determined whether it is " 1 " or " 1 ", i.e., 2, and if it is not " 1 ", the process proceeds to step S52. If "1", go to step S50. In step S50, after step S48, it is determined whether the left data value indicating the remaining data size value remaining after transmission is "0" or "0", and if it is determined as "0", , The process proceeds to step S56, and if not " 0 ", proceeds to step S54.

In step S52, when the result of the determination in step S48 is not "1", that is, the pad variable is "2", the step is executed. , For example, a process as shown in FIG. 3C), and then proceeds to step S58. Step S58 is a step of determining whether the quotient is greater than or less than 25. If the quotient is less than 25, the process proceeds to the next step S56, and vice versa. Step S54 is executed when the pad variable is " 1 " and the size variable value of the remaining data is not " 0 " in step S48. After performing, the process proceeds to the next step (S60).

On the other hand, step S56 is executed when the remaining data variable value is "0" in step S50 and the quotient of the determination result of step S58 is less than 25. After the pad unit according to the pad variable 1 of FIG. 3D performs the operation, the process proceeds to the next step S60. Step S60 is a step of determining whether the data to be transmitted currently is data of the last part after going through the above-described steps. If the result is not the last step, the process proceeds to step S68 of terminating the CPCS layer processor operation. If it is the last part, the process proceeds to step S62.

Step S62 is a step of determining whether the quotient is greater or less than 25 if the data to be transmitted is the last part. If the quotient is not less than 25, the process proceeds to step S64 and vice versa. If is, the process proceeds to step S66. In this case, step S64 is executed only when the quotient of the determination result in step S62 is not less than 25. After performing the PAD1 work routine described later, the process proceeds to step S66.

Step S66 is a step of finally adding the CPCS trailer after performing the steps S62 and S64 (since this process is not directly related to the present invention, detailed descriptions are omitted). Proceeding to S68, the operation is terminated.

3C is a diagram illustrating a process of adding a PAD according to the present invention, which is also performed by the CPCS layer processor 125 described above. First, in step S70, the task is executed, and the flow proceeds to step S72, in which the counting variable (i) value for performing the work, i.e., the number of pads required by the pad portion, is added to the first variable ( i) is set to " 0 ", and the pad unit sets the variable temp to the value obtained by subtracting the remaining value obtained at 48 octets, and then proceeds to the next step S74.

Step (S74) is a step of comparing the value of the variable (i) obtained by the step with the value of the variable (i) which is sequentially increased by 1 through the step (S72) and step (S74) to be described later, that is, the It is determined whether the value of the counting variable (i) is larger or smaller than the value of the pad part. If the counting variable value is not smaller than the value of the variable part, the process proceeds to step S76 to end the operation. In the opposite case, the process proceeds to the next step S78. In step S78, as described above, 1 is sequentially added to the counting variable, and then, this value is set again as a new counting variable i so that the pad unit can continue the operation by the value of the temp. ) And simultaneously fill the PAD area with " 0 " by the predetermined number (temp).

Referring now to FIG. 3D, there is shown a process for executing a PAD1 task. That is, this routine is a routine to be executed after steps S50 and S58 and after execution of step S64, as described with reference to FIG. First, the operation is started through step S80, and then, in step S82, a value of the counting variable i, which is different from that described above, is assigned to "0". The reason for allocating this is as described above. Step S84 is a step for determining whether the value of the variable is greater than or less than 40 octets, i.e., 40 octets, after the step S82. The process proceeds to S86) to end the operation, and in the opposite case, the process proceeds to the next step S88.

Lastly, in step S88, when the counting variable value reaches 40, the value of the counting variable is reset to a new counting variable by adding "1" to the counting variable value to return to the step S84 to continue the operation. Up to "0" is continuously and sequentially added to the area to which the corresponding pad is to be added.

As described above, according to the present invention, the pad variable can be easily added to the CPCS region in the transmitting AAL layer by determining its pad variable according to the CPCS data currently transmitted by the work routine proposed by the present invention. There is an advantage.

Claims (4)

Data is transmitted in units of a predetermined partition among all data to be transmitted, and data of a predetermined amount is sequentially transmitted first among the predetermined partition units, and trailer information is transmitted after all of the predetermined data amount is transmitted. Add a pad to the CPCS region of a transmit-side asynchronous delivery mode adaptation layer (AAL) processor according to the data to be transmitted (common section convergence sublayer (CPCS) data) A method of determining a pad variable and adding a pad according to the determined pad variable, the method comprising: a first variable representing a size of data transmitted among the total transmission data to be transmitted, among the pad variable and the total data to be transmitted; A first step of initializing a third variable indicating whether the portion of data to be transmitted is the last part; and after the first step A second step of determining whether a first variable value is less than or equal to the total data to be transmitted and whether or not the third variable value is the last part; and the difference between the total data to be transmitted and the first variable value tube in the second step When the (residual data) value is smaller than the predetermined division area unit and indicates that the value of the third variable is not the last part, the remaining data and the data of the predetermined amount in the predetermined division area unit are calculated and remainder. And a quotient value, and determining the first and second pad variables (pad) in response to the measured remainder and the quotient value, and for the first pad variable determined in the third step, the preset division. The first pad unit measured using the area unit and the measured remaining value adds the pads continuously and sequentially in the number corresponding to the area, and is determined in the third step. The second pad variable has a fourth step of adding pads continuously and sequentially as many as the number corresponding to the area of the second pad unit excluding trailer information in the size of the preset partition unit. Pad parameter determination and pad addition method. The method of claim 1, wherein when the difference (residual data) between the total data to be transmitted and the value of the first variable is greater than the predetermined partition unit as a result of the determination in the third step, Add the size of the predetermined division area unit, reset the added value to a size variable (fourth variable) of new pre-transmitted data, and the fourth variable is continuously operated by the second and third steps. And further comprising a fourth step of returning to said second step so as to be executable. 3. The method of claim 2, wherein the determining of the pad variable in the third step comprises comparing the measured quotient with a first reference value obtained by dividing the preset transmission data by the predetermined division area unit, wherein the quotient value is the first reference value. The first pad variable is larger when the remaining value is larger than a preset data size excluding the trailer information area in the partition area unit, and the quotient value is larger than the first reference value, and the remaining value is the division. If the size is smaller than the preset data size except for the trailer information area, the third pad variable is determined as the second pad variable. In the third step, the quotient value is smaller than the first reference value, and the remaining value is divided. If it is larger than the preset data size except for the trailer information area in the area unit, the third pad variable is determined. Determining the second pad variable when the value is smaller than one reference value and the remaining value is smaller than a preset data size excluding the trailer information area in the partition unit; and after the third B step, the third variable After setting the value to a variable indicating that the data is the last region, and after performing step 3A, the measured residual data, the determined pad variables, and the newly set variable value are transmitted to the CPCS layer processor. And a third step of returning to the second step so that the pad variable determination step is continued by adding the residual data to a first variable and setting it as a new variable (a fifth variable) representing the size of the previously transmitted data. Pad variable determination and pad addition method in broadband communication type 5. The method of claim 3, wherein the pad addition method for the first pad variable in the fourth step comprises: by the number corresponding to the first pad addition area measured using the predetermined division area unit and the measured residual value. Step 4A of sequentially and sequentially adding pads, and after the step, a quotient value measured using CPCS data of the next preset partition unit following the preset partition unit is N of the preset partition unit. Step 4B, which determines whether or not less than or equal to -1 times (where N times the partition unit is the size of data to be transmitted at once); and when the quotient value is smaller than the size in step 4B, the preset division. Step 4C of adding the pad corresponding to the area in the second pad unit excluding the trailer information in the size of the area unit, and after the steps 4B and 4C, the third variable value is the last. In the case of indicating the data area of the portion, step 4D of determining whether the measured quotient value is smaller than N-1 times of the preset division area unit; and when the quotient value is larger than the size as a result of determination in the 4D step The second pad unit excluding the trailer information is continuously and sequentially added to the area in the size of the preset partition unit, and when the quotient value is smaller than the size, the CPCS trailer information is added and transmitted. In step 4E, the method of adding a pad to the second pad variable in the fourth step includes: determining whether the size of the remaining data is "0" or not "0"; If the size of the remaining data is not "0", the first pad unit measured by using the preset partition unit and the measured residual value is determined in the region. The pads are continuously and sequentially added as many as the corresponding number, and if the size of the remaining data is "0", the second pad unit excluding the trailer information in the size of the preset partition unit corresponds to the area. In step 4b, and after the steps 4a and 4b, determining whether the measured quotient value is smaller than N-1 times of the predetermined division area unit, and determining in step 4c. As a result, when the quotient value is larger than the size, the pad is continuously and sequentially added to the area of the preset partition unit except for the trailer information, corresponding to the area, and when the quotient value is smaller than the size. And a fourth step of adding and transmitting the CPCS trailer information.