KR19990053979A - Service Quality Control Method for Improving Transmission Service of Multimedia Communication - Google Patents

Abstract

The present invention relates to a service quality control method for improving a transmission service of multimedia communication.

In order to perform multimedia communication such as audio and video by forming a group of geographically dispersed entities, it is necessary to control the quality of service during data transmission so as to make use of the continuity of media data to be transmitted. Do. Conventionally, when data is transmitted and received in a group consisting of a plurality of sending objects and a plurality of receiving objects, a combination of one-to-one or one-to-n is realized. In this case, the user must manage the combination. There is a burden to perform separate quality of service control for each connection in the combination, and when the objects involved in group communication join or leave the group, the group configuration object is changed dynamically to reduce the quality of service. there was.

In order to solve this problem, in the present invention, all entities constituting the group collectively control the transmission quality of service of all data packet streams transmitted on the channel in performing multimedia data communication through the multicast channel. A service quality control method for improving a transmission service of a multimedia communication that can effectively control a service quality even in the dynamic change of the present invention is presented.

Description

Quality of Service Control Method for Improving Transmission Service of Multimedia Communication

The present invention relates to a method of controlling a quality of service for improving a transmission service of a multimedia communication. In particular, when a plurality of geographically dispersed entities form a group to perform many-to-many communication, all the entities constituting the group are multicast. In case of performing multimedia data communication through channel, it is possible to control the quality of service of all data packet streams transmitted to the panel as a whole. The present invention relates to a service quality control method.

Conventionally, a quality of service control method for improving the quality of service of data transmission when one side is a transmission entity and the other side is a reception entity through a one-to-one connection, and by extending it, one transmission in a one-to-N connection Quality of service control schemes for one-way data transmission in entities and multiple (N) receiving entities are centrally linked. Accordingly, using this method, data transmission / reception in a group consisting of N to M, that is, a plurality of transmitting objects and a plurality of receiving objects is realized by configuring a combination of one to one or one to N. However, in this case, the user who uses it has to manage such a combination, and there is a burden to perform separate quality of service control for each connection in the combination. If the group configuration entity is dynamically changed by attempting to leave or join the service, the burden on service control becomes more and more complicated.

Accordingly, the present invention utilizes a negotiation procedure for determining a reference value of quality of service elements to be maintained in a channel between entities within a group, and a service quality monitoring procedure for monitoring whether a packet stream transmitted after the reference value negotiation maintains a negotiation value. To provide a service quality control method for improving the transmission service of the multimedia communication that can improve the transmission service quality of the data packet stream transmitted to the channel when all the objects constituting the multi-media communication through the multicast channel There is this.

According to an aspect of the present invention, there is provided a method of controlling a quality of service for improving a transmission service of a multimedia communication according to the present invention, when all the objects constituting a group perform multimedia communication through a multicast channel. The negotiation procedure for determining the reference values of the quality of service factors for defining each of the steps includes defining a quality of service element, transmitting the quality of service elements from the connection initiation entity to the connection response entity, and the connection response entity receiving the quality of service element. Checking whether the quality of service element value proposed by the connection initiation entity is acceptable, and if the value proposed by the connection initiation entity is unacceptable as a result of checking whether the quality of service element value proposed by the connection initiation entity is acceptable, specifying a reason. To leave the group Terminating the negotiation; and checking that the quality of service element proposed by the connection initiation entity is acceptable, and if the value proposed by the connection initiation entity is acceptable, the values of quality of service elements that the connection response entity can accept. Transmitting to the connection initiating entity, checking whether the connection initiation entity that has received the response value from the connection initiation entity is whether the response entity is the sender, and if the response entity is the sender as a result of determining whether the response entity is the sender. After reducing the maximum number of senders, checking whether the current received response is the last response; and if the current received response is the last response, if it is not the last response, the response value is obtained from the connection response entity. Intermediate negotiation until proceeding to receive and return response values from all connection response objects. And determining whether the currently received response is the last response, and in the case of the final response, determining a final negotiation value of the quality of service factor, and determining the final quality of service factor determined by the connection initiating entity. Transmitting a negotiation value to the connection response entity, and the connection response entity receiving the final negotiation value of the connection initiation entity and the quality of service element stores the final negotiation value of the service element to complete negotiation with the connection response entity. Checking whether the additional start object has occurred, and if the additional participant has occurred as a result of the step of checking whether the additional start object has occurred, checking whether the additional start object has been allowed to transmit. And checking whether the additional participating entity is an entity that is allowed to transmit. If it is a non-participating additional entity, checking that the inclusion of this entity exceeds the maximum number of senders currently being applied to the multicast channel when the total number of entities currently authorized to transmit is exceeded; If it is determined that the total number of senders exceeds the maximum number of senders, rejecting an additional participant; and if the total number of senders has the maximum number of senders, If it is determined that the total number of entities that have the authority to send does not exceed the maximum number of senders, the connection initiating entity presents the quality of service element value to the additional participating entity; and the quality of service element from the connection initiating entity. The additional participating entity that receives the value accepts the quality of service element values proposed by the connection initiating entity. And checking whether the connection initiation entity can accept the proposed quality of service element value, if not, informing the connection initiation group of the group refusal to join the group, and if the connection initiation entity proposes As a result of checking whether the quality of service element value can be accepted, if the acceptance is possible, the notification is accepted by the connection initiating entity, and the connection initiation entity receives the acceptance notification.

In addition, the service quality control method for improving the transmission service of the multimedia communication according to the present invention for achieving the above object is that when all the entities constituting the group performs the multimedia communication through the multicast channel in the channel between the objects in the group The quality of service monitoring method for monitoring whether a packet stream transmitted after maintaining a negotiation value after negotiating a reference value of quality of service elements to maintain maintains a transmission monitor timer at a time point at which a transmitting entity starts transmitting a packet, and receives the receiving entity. Setting up and receiving a reception monitor timer each time the packet starts receiving, and the sending entity measures quality of service factors for transmission rate, delay, delay deviation, and error rate, and the receiving entity measures the reception rate, delay deviation, and error rate. Measuring quality of service factors Storing each of the measured quality of service elements to retain their value until the next measurement, checking whether the current measurement is in violation of the negotiation value, and wherein the current measurement is in violation of the negotiation value. If the current measurement value violates the negotiation value, and if the current measurement value does not violate the negotiation value, and if the current measurement value does not violate the negotiation value. Checking whether transmission or reception of data is completed; and if the transmission or reception of data is not completed, measuring quality of service factors in each of the transmitting entity and the receiving entity. A progress monitor and a transmission monitor when the transmission and reception of the data is completed as a result of And terminating the monitoring by terminating the ring timer and the reception monitoring timer, respectively.

1 is a block diagram illustrating the relationship between a quality of service controller and hardware;

2 is a block diagram illustrating the operation of a quality of service controller according to the present invention;

3 (a) and 3 (b) is a flowchart illustrating a service quality negotiation method of the service quality control method according to the present invention.

4 is a flowchart illustrating a service quality monitoring method of the service quality control method according to the present invention.

<Description of the symbols for the main parts of the drawings>

11: host processor 12: main memory

13 network connection device 14 service quality controller

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

1 is a block diagram illustrating a relationship between a quality of service controller and hardware.

The host processor 11 is connected to the main memory 12 through a system bus, while connected to the communication network connection device 13 through an input / output (I / O) bus and stored in the main memory 12. (14) to execute quality of service control for multi-party data transmission. In addition, the quality of service controller 14 is embedded in the main memory 12 to control quality of service such as negotiation and monitoring of the quality of service elements for the packet stream transmitted or received from the network connection device 14. On the other hand, the communication network connection device 13 performs a data service from the external communication network to the receiver of the data and the external communication network.

2 is a block diagram illustrating the operation of the quality of service controller according to the present invention, which is composed of a quality of service negotiation module 21 and a quality of service monitoring module 22.

The quality of service negotiation module 21 is a module for determining a negotiation value that all entities agree on a quality of service element so that all members of a group formed of a plurality of entities receive the same level of service. Quality factors include transmission rate, delay, delay deviation, and error rate. The transmission rate is the number of valid bytes transmitted per unit time, and the delay is defined as the time taken to transmit a packet and reach the receiver. In addition, the delay deviation is a deviation of the time that elapses before the transmitting packet reaches the receiving buffer, and the error rate is defined as the ratio of the number of retransmitted or lost packets to the number of transmitted packets per unit time. Quality of service negotiation is initiated by the connection initiating entity, which initially establishes a connection between the entities in the group.

The connection initiation entity first defines a proposed value for the quality of service elements that it wants to use in the multicast channel (211), and presents this element value to all connection response entities in the group (212). When the connection response entities that receive the proposed values of the quality of service elements from the connection initiation entity determine the acceptable values and respond to the connection initiation entity, the connection initiation entity receives the response values from all the connection response entities (213). ). The connection initiation entity determines a final negotiation value by calculating a common value among the proposal values proposed by the connection entity and the response values received from all the connection response entities. After that, the connection initiating entity notifies all the connection response entities of the determined negotiation value and provides the final negotiation value for the quality of service factors so that all the entities participating in the group can manage the negotiation values of the same quality of service factors. Thereafter, the service quality negotiation process is performed by storing the final negotiation value (216).

After the negotiation value is determined by the quality of service negotiation module 21, the quality of service monitoring module 22 collects transmission information such as transmission amount and transmission error amount while transmitting data, and collects statistical values about delay and delay deviation. It is measured (221). In addition, while receiving data, reception information such as a reception amount and a reception error amount is collected, and a statistical value of the deviation of the arrival time between packets of the received packet is measured (222). In order to monitor data transmission and reception status using collected information, rate and error rate are measured at regular intervals. At this time, the transmission monitor timer is started to periodically monitor the transmission state of the data (223), and the reception monitor timer is started (224) to periodically monitor the reception state. Whenever the transmission monitor timer expires, statistical values such as transmission transmission rate and transmission error rate during the timer interval are measured (225), and when the reception monitor timer expires, statistical values such as reception rate and reception error rate during the timer interval are measured. (226). The values of the measured quality of service factors are stored in the statistics store (227) and checked if the measurements violate the negotiation value (228). If a violation of the quality of service negotiation value is found, the user is notified of the violation (229).

3 (a) and 3 (b) is a flowchart illustrating a service quality negotiation method of the service quality control method according to the present invention, the operation of the connection start entity 31 for the connection response entity 32, Initiating a connection to the additional participating entity 34 shows the operation 33 of the entity.

Multimedia applications have various user requirements depending on the type of data used in the application, such as text, audio, and video. In order to accommodate the various demands of the user, quality of service factors such as transmission rate, delay, delay deviation, and error rate are represented as a range of values instead of a specific single value. The transfer rate is expressed as the maximum and minimum transfer rates, the delay as the maximum delay, the delay deviation as the maximum delay deviation, and the error rate as the maximum error rate, which are the maximum or minimum values for each quality of service by the user when transmitting data. This is an expression of user requirements that can be accepted. Each quality of service factor has a function that determines specific negotiation value according to their type. In one N-to-M multicast channel, various user requirements can be provided for each sender, but the transmission rate value of all entities transmitting Simplify the negotiation process by matching them to the transmission rate of the initiating entity.

The negotiation of the transmission rate is negotiated using the minimum transmission rate (I_Throughput _min ), the maximum transmission rate (I_Throughput _max ), and the maximum number of senders (Sender _max ) that can be simultaneously maintained between the connection initiation entity and the connection response entity. do. The I_Throughput values are the desired transmission rates when the number of senders is maximum Sender _max . In this case, the Sender _max value is used to predict the required transmission rate per single sender. Delay negotiation is achieved using the maximum allowable delay value (Delay _max ) between the connection initiation entity and the connection response entity to maintain on the multicast channel. In addition, the negotiation of delay deviation is negotiated using the maximum allowable delay deviation value (I_Jitter _max ) suggested by the connection initiation entity. The error rate, which specifies the tolerance of the transmission errors allowed for the connection, is negotiated using the maximum allowed error_rate _max . The error rate is used as a tool for detecting the status of the multicast channel and early detection of abnormalities during data transmission (301). ).

Connecting the start object is a I_Throughput _min, I_Throughput _max, Sender _max value for the transmission rate according to the service quality parameters received from the users, the Delay _max values for the delay, the I_Jitter _max values for the delay deviation, the Error_rate _max value for the error rates Send to connection response entity (302).

Connection response entities that have received I_Throughput _min , I_Throughput _max , Sender _max, Delay _max , I_Jitter _{max, and} Error_rate _max values from the originating entity (303) check if the quality of service element proposed by the initiating entity is acceptable (304). If the initiating entity is unable to accept the proposed value, it specifies the reason to request 305 to leave the group, and if so, responds to the initiating entity with the values of the quality of service elements it can tolerate. Determination of response values for each quality of service element is different for each quality of service element and follows the following rules.

First, the connection response entity responds with R_Throughput _min and R_Throughput _max for the transmission rate. R_Throughput _min and R_Throughput _max represent the minimum and maximum data rates that the responder can accept.Equation 1 cannot accept the rate negotiation and Equation 2 can accept the rate negotiation. Is the same as

R_Throughput _max > I_Throughput _max or R_Throughput _min <I_Throughput _min

R_Throughput _max ≤ I_Throughput _max and R_Throughput _min ≥ I_Throughput _min

Second, with regard to delay and error rate, the Delay _max and Error_rate _max suggested by the connection initiating entity leave the group if the connection responding entity accepts or cannot.

Third, for the delayed deviation, when the connection response entity can accept the I_Jitter _max suggested by the connection initiating entity, the connection response entity responds to the connection initiation object with the allowable delay deviation value (R_Jitter _max ). R_Jitter _max is a value considering delay delay buffer capacity such as I_Jitter _max received from the connection initiating entity and its own buffer capacity, and the condition that cannot accept delay deviation negotiation is shown in [Equation 3]. The possible conditions are as shown in [Equation 4].

I_Jitter _{max 〈} R_Jitter _max

I_Jitter _max ≥ R_Jitter _max

According to this rule, when the connection response entity determines and receives a response value from the chronological response entity (307), the connection initiation entity checks whether the response entity is the sender (308). As a result of determining whether the response entity is the sender, when the response entity is the sender, the maximum number of senders is reduced (309), and then it is checked whether the response currently received is the last response (310). If the result of the check is not the last response, the intermediate negotiation value is determined until the response value is returned from all the connection response entities (311). If the check result is the last response, the connection initiation entity determines the final negotiation value when receiving the response value from all the connection response entities (312). Determination of the negotiation value for each quality of service factor follows the following rules for each quality of service factor.

First, for the transmission rate, the connection initiation entity uses the R_Throughput _min and R_Throughput _max values received from the connection response entity, and calculates the negotiated values of the transmission rate N_Throughput _{min and} N_Throughput _max from Equation 5 as shown in Equation 5 below. ] Is determined as follows.

N_Throughput _min = MAX (R_Throughput _min (i), I_Throughput _min )

N_Throughput _max = MIN (R_Throughput _max (i), I_Throughput _max )

Where i represents each connection response entity.

Through the rate negotiation process, the transmission rate (R_Throughput) of the connection response entities is determined as N_Throughput, and the individually allowed transmission rate (S_Throughput) for the connection response entity with sending authority is the value reflecting the number of senders in N_Throughput. Equation 6] is used to monitor the packet transmission rate for each sender at the time of packet transmission and the sender of the receiver at packet reception based on this value.

S_Throughput _max = N_Throughput _max / Sender _max

S_Throughput _min = N_Throughput _min / Sender _max

Second, the connection initiation entity receiving the delay deviation allowance (R_Jitter _max ) of the connection response entities from the connection response entities uses the R_Jitter _max value to negotiate the minimum value among the allowable delay deviations allowed by the connection response entities. N_Jitter _max ), and is represented by Equation 7.

N_jitter _max = MIN (R_jitter _max (i))

Where i represents each connection response entity.

Third, the delay and error rate are determined as the negotiation value by the initial proposed value of the connection initiating entity, and is expressed as shown in [Equation 8].

N_Delay _max = I_Delay _max

N_Errorate _max = I_Errorate _max

When the connection initiating entity informs all connection response entities that have successfully negotiated, the final determined values of N_Throughput _min , N_Throughput _max , N_Delay _max , N_jitter _max , and N_Errorrate _max (313), the connection response entity receives the final negotiation value from the connection initiating entity. 314), the connection initiation entity stores the determined final negotiation value (315) and then completes the negotiation by indicating completion of negotiation. The connection response entity also ends the negotiation by storing the final negotiation value received from the connection initiation entity (315).

After the negotiation with the connection response entity is completed, it is necessary to respond to the dynamic change of the entities in the group, such as joining or leaving a new entity in the group, and ensuring transmission authority of the entities that can only be received. Is done.

First, the connection start entity checks whether an additional participant has occurred (316), and if the additional participant has occurred, checks whether the generated additional participant is an entity that is allowed to transmit (317). Test results, by checking whether the case of additional participating entity that is transmitted is not acceptable to exceed the number Sender _max up to the sender that you want to include this object, the total population that has the current transmission rights to the multicast channel, the transmission rights If the total number of objects with the maximum number of senders exceeds the maximum number of senders, the additional participating objects are rejected. If the total number of objects with sending rights does not exceed the maximum number of senders, the initiating object is applied on the multicast channel. Present quality of service factor values (N_Throughput _min , N_Throughput _max, N_Delay _max, N_jitter _max, N_Errorrate _max ) are presented to the additional participating entity (320). An additional participant that receives such a quality of service element value from the connection initiation object (321) checks whether the connection initiation object can accept the proposed quality of service element value (322), and denies joining the group to the connection initiation object if it is not possible. Notification 323 is made. If the allow is possible, the negotiation is terminated by the accept notification 324 of the connection initiating entity, and the connection initiation entity receives the accept notification 325.

If the receiving object requests sending permission to the connection initiation object, the connection initiation object compares the maximum number of senders (Sender _max ) set at the time of negotiation. Send permission is granted only if the number of objects that can be sent is currently less than Sender _max ;

4 is a flowchart illustrating a service quality monitoring method of the service quality control method according to the present invention.

Multimedia data having the property of continuity should be transmitted to satisfy the value of quality of service elements required by the application, and measurement of quality of service elements is necessary to confirm that quality of service elements are guaranteed. When the negotiation about the service quality factor is completed from the service quality negotiation procedure, data is transmitted. During the data transmission, the data is periodically monitored to maintain the negotiated value. Monitoring is performed separately from the sending entity and the receiving entity according to the type of quality of service factors. On the sending entity side, service quality factors for transmission rate, delay, delay deviation, and error rate are measured. On the receiving entity side, quality of service factors for reception rate, delay deviation, and error rate are measured.

First, the transmitting entity installs and operates a transmission monitor timer at the time of starting packet transmission to measure transmission rate and error rate, and the receiving entity installs a reception monitor timer at the time of starting packet reception to measure reception rate and error rate. Operation (401). These two timers are started periodically at regular time intervals, i.e. timer intervals, until data transmission and reception is completed. The sending entity then measures the quality of service factors for transmission rate, delay, delay and error rate, and the receiving entity measures quality of service factors for reception rate, delay and error rate (402). That is, in order to measure the transmission rate, the sender calculates the amount of packets successfully transmitted for all receiving objects from the moment the timer is started to the interval of the timer in bytes, and divides the calculated value by the monitor timer interval per unit time. The measurement value (M_Send_Throughput) for the average transmission rate is obtained, and the measurement value (M_Send_Error) for the error rate is calculated by dividing the number of retransmitted packets by the total number of transmitted packets in order to measure the error rate. In addition, the measurement of the delay of the transmitting object is performed by recording the current timestamp in the packet transmitted by the transmitting object and transmitting the received response including the same timestamp value for the data transmitted from the receiving objects. Calculate the instantaneous delay value by calculating the difference (Instant_Delay) between the timestamp value included in the response and the received response, and assign the weight to reduce the effect of the instantaneous delay value on the overall delay average as follows: Calculate the value.

M_Send_Delay = (1 -α) M_Send_Delay + α × Instant_Delay

At this time, 0 <α <1.

In order to measure the reception rate, the receiving entity calculates the amount of packets successfully received in the unit of bytes from the moment the timer is started to the interval of the timer, and divides the calculated value by the monitor timer interval to measure the average reception rate per unit time. To obtain (M_Receive_Throughput), and to measure the error rate, calculate the measurement value (M_Receive_Error) for the error rate by dividing the number of packets that require retransmission by the total number of received packets. The measurement of the delay deviation of the receiving object is made by measuring the time difference between arriving packets. This is measured by each sender. In order to reduce the effect of instantaneous deviations between specific packets on the overall average value, weights are assigned to instantaneous deviations (InterArrival_Jitter) and estimated as follows.

M_Receive_Jitter = (1-β) M_Receive_Jitter + β × InterArrival_Jitter

At this time, 0 <β <1.

After the measurement of each quality of service element is completed, the measured quality of service elements are stored to retain their values until the next measurement (403), and then the current measurement values by the criteria shown in [Table 1] and [Table 2]. Check if it violates this negotiation value (404).

Measure negotiation value Transfer rate M_Send_Throughput> S_Throughput _max M_Send_Throughput <S_Throughput _min delay M_Send_Delay> N_Delay _max, Delay deviation M_Send_Jitter> N_jitter _max Error rate _Send_Error> N_Errorrate _max

Measure negotiation value Reception M_Receive_Throughput> S_Throughput _max M_Receive_Throughput <S_Throughput _min Delay deviation M_Receive_Jitter> N_jitter _max Error rate M_Receive_Error> N_Errorrate _max

If the measurement violates the negotiated value, the user is informed of this (405). In other words, if the sending object finds a negotiated value violation, the user is notified of the violated quality of service element and its value. If the receiving object finds the negotiated value violation, the violating quality of service element and its value and the negotiated value violation and The identifier of the relevant sending entity is informed to the user so as to determine whether the reception status from which sender is bad. Thereafter, the operation 406 checks whether the transmission or reception of the data is completed, and if the transmission or reception of the data is not completed, proceed to step 402 of measuring quality of service factors at each of the transmitting entity and the receiving entity. When this is completed, monitoring is terminated by terminating the transmission monitoring timer and the reception monitoring timer, respectively (407).

As described above, according to the present invention, each entity in the group exchanging multimedia information negotiates the transmission amount, delay, delay deviation and error rate to a specific range value and monitors whether the packet stream maintains the negotiation value during data transmission and reception, When the network fails to maintain the negotiated range due to the dynamically changing load, the user is informed of the fact that the service quality is excellent.

Claims (13)

When all the entities constituting the group perform multimedia communication through the multicast channel, the negotiation procedure for determining the reference values of the quality of service factors to be maintained in the channel between the entities in the group includes defining the quality of service elements, respectively; Transmitting the quality of service element from a connection originating entity to a connection response entity; Checking, by the connection response entity that has received the quality of service element, whether the quality of service element value proposed by the connection initiation entity is acceptable; Checking that the quality of service element value proposed by the connection initiation entity is acceptable and specifying the reason why the connection initiation entity cannot accept the proposed value, requesting to leave the group and ending negotiation; Checking the quality of service element values suggested by the connection initiating entity and transmitting the values of quality of service elements allowed by the connection response entity to the connection initiation entity if the value of the service originating entity is acceptable. Wow, Checking, by the connection initiation entity receiving the response value from the connection response entity, whether the response entity is a sender; Determining whether the response entity is the sender, if the response entity is the sender, reducing the maximum number of senders, and then checking whether the currently received response is the last response; As a result of checking whether the presently received response is the last response, if it is not the last response, proceeding to receiving a response value from the connection response entity until the response value is returned from all connection response entities. Making the decision, Determining whether the currently received response is the last response, and when the final response is determined, determining a final negotiation value of the quality of service factor; Transmitting a final negotiation value of a quality of service factor determined in the connection initiation entity to a connection response entity; The connection response entity receiving the final negotiation value of the connection initiation entity and the quality of service element and storing the final negotiation value of the service element to complete negotiation with the connection response entity; Checking whether the connection initiating entity has an additional participating entity; If the additional participant has occurred as a result of checking whether the additional participant has occurred, checking whether the generated additional participant is an entity that is allowed to transmit; If the additional participant is an additional participant that is not allowed to be transmitted, it is determined that the total number of entities currently having transmission authority when including this object is applied to the multicast channel. Checking if the number of senders is exceeded, Rejecting an additional participant if the total number of individuals with the transmission right exceeds the maximum number of senders as a result of checking that the total number of individuals with the transmission right exceeds the maximum number of senders; As a result of checking that the total number of entities having the transmission authority exceeds the maximum number of senders, if the total number of entities having the transmission authority does not exceed the maximum number of senders, the connection initiating entity adds the quality of service element value to the additional participants. To present, Checking whether an additional participant receiving the quality of service element value from the connection initiation entity can accept the quality of service element value proposed by the connection initiation entity; Checking whether the connection initiation entity can accept the proposed quality of service element value, and if not, notifying the connection initiation object of group initiation denial; Checking whether the connection initiation entity can accept the proposed quality of service element value, and if the acceptance is allowed, the notification of acceptance is made to the connection initiation entity, and the connection initiation entity receives the acceptance notification. Quality of service control method for improving the transmission service of multimedia communication, characterized in that. 2. The method of claim 1, wherein the quality of service element is a rate negotiated using a minimum rate, a maximum rate, and a maximum allowable number of senders simultaneously to maintain a multicast channel between the connection initiation entity and the connection response entity; A delay value negotiated between the initiation entity and the connection-response entity using the maximum allowable delay value to maintain on the multicast channel, A delay deviation value negotiated using the maximum allowable delay deviation value presented by the initiating entity; Quality of service for improving the transmission service of the multimedia communication, characterized in that the error rate negotiated using the maximum allowable error rate between the connection start object and the connection response object. The method of claim 1, wherein the determination of the response values of the quality of service elements received by the connection response entity from the connection initiation entity is not acceptable when the rate negotiation is not acceptable. [Maximum rate allowed by responder> Maximum rate Or the minimum rate allowed by the responder <minimum rate If the rate negotiation is acceptable, [Maximum rate allowed by responder ≤ maximum rate Transfer rate ≥ minimum transfer rate] If the delayed negotiation is not acceptable, Maximum allowable delay deviation value <Allowable delay deviation allowance If the delayed deviation negotiation is acceptable, A maximum allowable delay deviation value ≥ a delay deviation allowable value of a responder, which is a quality of service control method for improving a transmission service of a multimedia communication. The method of claim 1, wherein the determination of the final negotiation value of the initiation entity for the response to the quality of service factors, [Minimum rate negotiated value = MAX (Minimum rate (i), minimum rate allowed by responder]] [Maximum rate negotiated value = MIN (maximum rate (i), maximum rate allowed by the responder)] For a rate that is allowed individually for a connection response entity that has permission to send, Maximum Rate Permitted Individually for Connection Response Objects with Sending Privileges = Maximum rate negotiation value / maximum number of senders] Minimum baud rate allowed individually for connection response objects with send permission = Minimum rate negotiation value / maximum number of senders] In case of delayed deviation [Negotiated delay deviation = MIN (maximum delay deviation allowed by responder)] In case of delay, [Negotiated delay = maximum negotiated maximum delay] For error rates, A quality of service control method for improving a transmission service of a multimedia communication, characterized in that [negotiated error rate = maximum error rate negotiated at first]. Where i is each connection response entity. When all the members of the group perform multimedia communication through the multicast channel, after negotiating the reference values of the quality of service elements to be maintained in the channel between the objects in the group, the group checks whether the transmitted packet stream maintains the negotiation value. How to monitor quality of service Installing and starting a transmission monitor timer at the time when the sending entity starts packet transmission, and installing and starting a reception monitor timer at the time when the receiving entity starts packet reception; The transmitting entity measures quality of service factors for transmission rate, delay, delay deviation and error rate, and the receiving entity measures quality of service factors for reception rate, delay deviation and error rate; Storing each of the measured quality of service factors to retain its value until the next measurement; Checking if the current measurement violates the negotiated value, Checking that the current measurement value violates the negotiation value, and notifying the user when the current measurement value violates the negotiation value; Checking whether the current measurement value violates the negotiation value and, if the current measurement value does not violate the negotiation value, checking whether data transmission or reception is completed; Checking whether the transmission and reception of the data is completed, and if the transmission and reception of the data are not completed, proceeding to measuring the quality of service factors at each of the transmitting entity and the receiving entity; When the transmission and reception of the data is completed as a result of checking whether the transmission and reception of data is completed, the step of terminating the monitoring by ending the transmission monitoring timer and the reception monitoring timer respectively, characterized in that for the transmission service enhancement of the multimedia communication How to control quality of service The transmission rate of the transmitting entity is calculated by calculating the amount of packets successfully transmitted for all receiving entities from the moment the timer is started to the interval of the timer in bytes, and dividing the calculated value by the monitor timer interval. A service quality control method for improving a transmission service of a multimedia communication, characterized in that measured by obtaining a measurement value for the average rate per hour. 6. The method of claim 5, wherein the error rate of the transmitting object is measured by dividing the number of retransmitted packets by the total number of transmitted packets. 6. The method of claim 5, wherein the measurement of the delay of the transmitting object includes receiving a response including the same time stamp value for data transmitted from the receiving objects after recording and transmitting the current time stamp in the packet transmitted by the transmitting object. On receipt, the instantaneous delay value is calculated by calculating the difference between the current time and the timestamp value included in the incoming response, and the average delay value is assigned by assigning weights to reduce the effect of the instantaneous delay value on the overall delay average value. Quality of service for improving the transmission service of the multimedia communication, characterized in that for calculating the. 10. The method of claim 8, wherein the average delay value is calculated using Equation 9 below. [Average delay value = (1-α) average delay value + α × difference between the current time and the time stamp value included in the reception response At this time, 0 <α <1. The method of claim 5, wherein the reception rate of the receiving entity is measured by calculating the amount of packets successfully received from the moment the timer is started until the interval of the timer in bytes and dividing the calculated value by the monitor timer interval. Quality of service for improving the transmission service of the multimedia communication. 6. The method of claim 5, wherein the error rate is measured by dividing the number of packets requesting retransmission by the total number of received packets. 6. The method of claim 5, wherein the measurement of the delay deviation of the receiving object is measured by the time deviation between arriving packets, which is measured for each sender to reduce the effect of the instantaneous deviation between specific packets on the overall average value. A method of controlling a quality of service for improving a transmission service of a multimedia communication, wherein the weight is assigned and measured using Equation 10 below. [Delay Deviation of Recipient Object = (1-β) Delay Deviation of Receiver Object + β × Instant Deviation] At this time, 0 <β <1. 6. The method according to claim 5, wherein the condition for checking whether the current measured value violates the negotiated value is the transmission rate of the transmitting object. [Average transfer rate (measured value)> Maximum transfer rate (negotiated value) allowed individually for connection response entity with sending authority] [Average transfer rate (measured value) 〈Maximum transfer rate (negotiated value) allowed individually for connection response entity with sending authority] In case of delay value of sending object, [Mean delay (measured value)〉 maximum delay (negotiated value)] In case of delay deviation of the transmitting object, [Mean delay deviation (measured value)> Maximum delay deviation (negotiated value)] For error rates, [Average Error Rate (Measured Value)> Maximum Error Rate (Negotiated Value)] In case of receiving rate of receiving object, Average Receive Rate (measured value)> Maximum baud rate (negotiated value) allowed individually for a Connection Response entity with Send permission Average reception rate (measured value) <the minimum transmission rate (negotiated value) allowed individually for a connection response entity with sending permission] In the case of the delay of the receiving object, [Receive delay deviation (measured value)> Maximum delay deviation (negotiated value)] In case of error rate of receiving object, [Receive Error Rate (Measured Value)> Maximum Error Rate (Negotiated Value)]