KR20060083051A - Method for input/output based game-synchronization for the network game and the moblie phone thereof - Google Patents

Abstract

The present invention relates to an I / O-based game synchronization method of a network game and a mobile communication terminal for the same. In particular, the buffer delay time is calculated through a connectionless protocol packet including a timestamp, key input information, and a 32-bit checksum. The present invention relates to an I / O-based game synchronization method for a network game that outputs game information late by a delay time, and a mobile communication terminal for the same.

To this end, the present invention includes a first step of calculating a buffer delay time for compensating for a signal transmission delay generated on a network from time stamp information included in a connectionless protocol packet received from a mobile communication terminal of a game opponent connected through a network; If there is a first key input by the user to proceed with the game, the second key included in the connectionless protocol packet received from the terminal of the game by delaying the information corresponding to the key input by the calculated buffer delay time. And a second step of synchronizing with information corresponding to an input and outputting the same to a game in progress.

Buffer delay time, connectionless protocol, repetitive transmission

Description

I / O based game synchronization method of network game and mobile communication terminal for same {method for input / output based game-synchronization for the network game and the moblie phone

1 is a conceptual diagram according to a synchronization system of a mobile network game according to an embodiment of the present invention.

2 is a block diagram illustrating a configuration of the first mobile communication terminal shown in FIG. 1 according to an embodiment of the present invention.

3 is a detailed configuration diagram of the control unit shown in FIG. 2 according to the present invention.

4 is a block diagram of a UDP packet according to the present invention.

5 is a flowchart illustrating a method for synchronizing a mobile network game according to an embodiment of the present invention.

6 is a flowchart of a buffer time value calculation method according to the present invention.

7 is a flowchart illustrating a fault overcoming method according to the present invention.

8A and 8B are flowcharts illustrating a repetitive transmission method of a UDP datagram according to the present invention.

The present invention relates to an I / O-based game synchronization method of a network game and a mobile communication terminal for the same. In particular, the buffer delay time is calculated through a connectionless protocol packet including a timestamp, key input information, and a 32-bit checksum. The present invention relates to an I / O-based game synchronization method for a network game that outputs game information late by a delay time, and a mobile communication terminal for the same.

Recently, the mobile network market is exploding, and board games, RPG games, and large current games are emerging. Turn-based games such as board games do not have much difficulty in implementing network games because there is not much information exchange per hour. On the other hand, games that require synchronization of games in real time, such as large current games, and have a relatively large amount of information exchange per hour, are being turned away from developers due to the limitations of their environment, such as mobile network transmission speeds. There are many problems in this regard.

Conventional mobile network games are approaching the same method as the method for the networking of mobile games in the development method. That is, most data constituting game data such as screen data and key input data is exchanged for synchronization. In addition, the synchronization is implemented in a state where the reliability is guaranteed by using a connection protocol, such as TCP / IP protocol for the synchronization of the game.

The above approach does not have a problem when the network environment is good, such as the network bandwidth is guaranteed to be above a certain level, but the mobile network environment is much weaker than the general network environment, so synchronization is required in a large current game that requires real-time synchronization. There is a problem that the packet transmission amount is too large for slowing down the game speed and losing the packet for synchronization.

In order to solve the above problem, a packet skip algorithm or a packet that has already received information of a lost packet or a packet skip algorithm that maintains synchronization by slowing motion by reducing frames per second corresponding to a lost packet Dead reckoning algorithms are inferred from the information contained in and reflected in the game. However, in the packet skip method, the user feels a break in the game screen as the frame rate decreases, and the dead reckoning method adds excessive overhead to the processor to infer the information contained in the lost packet. There was this.

An object of the present invention is to solve the above problems, and the speed of the mobile game using the connectionless protocol and the buffer time value for the synchronization of the game to synchronize only the remote key input value, not various objects. To improve.

Another object of the present invention is to increase the capacity of the entire network by reducing the amount of information transmitted through the network for the synchronization of the game.

Another object of the present invention is to provide a system development kit (SDK) and an application program interface (API) for implementing the above algorithm to simplify game development.

According to an aspect of the present invention for achieving the above object, to compensate for the signal transmission delay generated in the network from the time stamp information contained in the connectionless protocol packet periodically received from the mobile communication terminal of the game opponent connected via the network Calculating a buffer delay time for the first step; If there is a first key input by the user to proceed with the game, the second key included in the connectionless protocol packet received from the terminal of the game by delaying the information corresponding to the key input by the calculated buffer delay time. And a second step of synchronizing with information corresponding to an input and outputting the same to a game in progress.

According to another aspect of the present invention for achieving the above object, a storage unit for storing a mobile network game; An input unit configured to receive data regarding the progress of the game; A display unit which displays the progress of the game; Calculate a buffer delay time for compensating for a signal propagation delay occurring on a network from time stamp information included in a connectionless protocol packet received from a mobile communication terminal of a game opponent connected through a network and providing a user's information to proceed with a game. When there is one key input, the information corresponding to the key input is delayed by the calculated buffer delay time to synchronize with the information corresponding to the second key input included in the connectionless protocol packet received from the terminal of the game opponent. And a controller for controlling to output to a game in progress.                     

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

1 is a conceptual diagram according to a synchronization system of a mobile network game according to an embodiment of the present invention.

Referring to Figure 1, the mobile network game synchronization system according to the present invention is a game server 100, time synchronization server 200, the first mobile communication terminal 300, the second mobile communication terminal 400, And the Internet 500.

The game server 100 may download to the first mobile communication terminal 300 or the second mobile communication terminal 400 when requested by the first mobile communication terminal 300 or the second mobile communication terminal 400. Save mobile network games.

When the time synchronization server 200 receives time information from the first mobile communication terminal 300 and the second mobile communication terminal 400, the first mobile communication terminal 300 and the second mobile communication terminal. Time information for synchronizing the clock of 400 is transmitted.

The first mobile communication terminal 300 and the second mobile communication terminal 400 may store the mobile network game in advance or download and store the mobile network game from the game server 100.

In addition, when the game is executed, time information is transmitted from the time synchronization server 200 for synchronization between the mobile communication terminals, and then a UDP packet including a time stamp and a 32-bit checksum is transmitted to the mobile communication device. Send to the terminal.

If there is a key input of the mobile communication terminal when generating the packet, key input information is added to the UDP packet and transmitted.

2 is a block diagram illustrating a configuration of the first mobile communication terminal shown in FIG. 1 according to an embodiment of the present invention.

Referring to FIG. 2, the first mobile communication terminal 300 shown in FIG. 1 according to an embodiment of the present invention may include a wireless communication unit 302, a storage unit 304, an input unit 306, and a display unit 308. ) And the controller 310.

The wireless communication unit 302 is controlled by the control unit 310, and transmits and receives a voice signal for a telephone call with the other party, the connectionless input and output information for the execution of the mobile network game program and mobile network game. It transmits and receives using UDP (user datagram protocol).

The storage unit 304 stores operation programs and system programs necessary for the control of the controller 310, and in particular, the mobile network game program and various device drivers and programs necessary for executing the mobile network game.

The input unit 306 is composed of a plurality of numeric keys, menu keys, and function keys for performing various functions, and generates key input signals corresponding to keys input by a user to output key input information to the controller 310. . In particular, the user inputs a key input necessary for the progress of the mobile network game and outputs it to the controller 310.

The display unit 308 is a display device such as a liquid crystal display (LCD). The display unit 308 displays the state of the first mobile communication terminal 300 or the progress of the game under the control of the controller 310. In particular, the screen objects of the network game are displayed in correspondence with the key input information of the mobile network game transmitted through the input unit 306 and the wireless communication unit 302.

The control unit 310 controls the overall operation of the first mobile communication terminal 300 and at the same time a mobile network game stored in the storage unit 304 of the first mobile communication terminal 300 through the game and the network. Control to run in sync with other connected mobile network games.

In detail, the controller 310 calculates a predetermined buffer delay time for synchronizing a mobile network game that is executed in the first mobile communication terminal 300 and the second mobile communication terminal 400 of the game opponent. Delay the key input information about the mobile network game of the mobile communication terminal input through the input unit 306 by the time and to the game of the mobile communication terminal of the game opponent received through the wireless communication unit 302. A packet which is a time required for transmitting a UDP packet including key input information related to the key input information from the buffer delay time to the first mobile communication terminal 300 from the second mobile communication terminal 400. By delaying the reception time by a value less, it is controlled to be reflected in the game executed in the first mobile communication terminal (300). That is, the key inputs related to the progress of the game of the first mobile communication terminal 300 and the second mobile communication terminal 400 are reflected in the game after the buffer delay time has passed from the input time. Synchronize games between

In addition, game data other than the key input information of the game executed in the first mobile communication terminal is also reflected in the game executed in the first mobile communication terminal 300 after a time corresponding to the buffer delay time. To control the output.

In addition, the controller 310 controls to execute a failure overcoming algorithm, which will be described later, for overcoming a failure in the packet including the key input information received through the wireless communication unit 302.

The configuration of the second mobile communication terminal 400 shown in FIG. 1 is the same as that of the first mobile communication terminal, and thus a detailed description thereof will be omitted.

3 is a detailed configuration diagram of the control unit shown in FIG. 2 according to the present invention.

Referring to FIG. 3, the detailed configuration of the control unit 310 shown in FIG. 2 according to the present invention will be described. The control unit 310 of the mobile communication terminal according to the present invention is a mobile communication processing unit 311, a buffer time value calculation. The unit 312 includes an input delay processing unit 313, an output delay processing unit 314, and a fail over processing unit 315.

The mobile communication processing unit 311 is configured to operate using a known mobile communication technology as a module for performing a mobile communication service using a radio resource in the mobile communication terminal, and thus detailed description thereof will be omitted.

The buffer delay time calculation unit 312 delays the key input information included in the UDP packet received from the mobile communication terminal of the mobile network game opponent and the key input information related to the progress of the game input through the input unit 306. A predetermined buffer delay time to be reflected in the game is calculated.

The input delay processing unit 313 delays the key input information related to the progress of the game input through the input unit 306 by the calculated buffer delay time and converts the key input information included in the UDP packet into the calculated buffer. The delay time is controlled by reflecting the game by delaying the packet reception time of the corresponding packet. This is because the key input information from the second mobile communication terminal 400 of the game opponent is reflected in the game after the buffer delay time from when the key input is input to the second mobile communication terminal. The key input information input from the mobile communication terminal 300 is also delayed by the same time for synchronization of the game and reflected in the game.

The output delay processing unit 314 controls other data such as screen object information other than the key input information of the game to be delayed by the calculated buffer delay time to be reflected to the game and outputted to the display unit 308. This is because the key input information about the game is reflected in the game after the buffer delay time, so that the remaining information about the game is reflected thereafter.

Information about the game other than the key input information of the game is not transmitted through the network. It synchronizes only key input information so that the first mobile communication terminal 300 and the second mobile communication terminal 400 can be synchronized in the game progress even if they proceed, respectively, and reduce the amount of transmission of information through the network. This is because the speed can be progressed seamlessly.

The failover processing unit 315 controls to transmit a copy UDP packet of the packet after a predetermined time after transmitting the original UDP packet related to the game. This is to allow the game to proceed using the copy UDP packet when there is an error in the original UDP packet.                     

In addition, after receiving the original UDP packet from the second mobile communication terminal 400 of the game opponent, if there is an error by checking whether there is an error in the original UDP packet, a copy of the original UDP packet exists in a buffer. Determine whether or not. If the copy UDP packet exists in the buffer, it is checked whether there is an error in the copy UDP packet, and if there is no error, the original UDP packet is replaced with the copy UDP packet. If the copy UDP packet does not exist in the buffer or there is an error in the copy UDP packet, an algorithm such as packet skipping or dead reckoning is used to control a failure caused by the lost packet.

4 is a block diagram of a UDP packet according to the present invention.

Referring to FIG. 4, a UDP packet transmitted by a mobile communication terminal for executing a mobile network game includes a UDP header and a data portion.

The UDP header consists of a source port number, a destination port number, a message length, and a 16-bit checksum of a packet, the specific function of which is defined in a known request for comment (RFC) 768 document. Will be omitted.

The data portion is composed of an original portion consisting of time stamp 1, key input information 1, and 32 bit checksum 1, and a copy portion consisting of time stamp 2, key input information 2, and 32 bit checksum 2.

The time stamp 1 indicates a time at which a packet including corresponding time stamp information is transmitted. The time stamp is used as information for calculating a transmission time between the mobile communication terminal that has transmitted the packet and the mobile communication terminal which has received the packet. In addition, the mobile communication terminal receiving the packet is used to determine the order of the received packet.

The key input information 1 relates to a mobile network game that is executed in the mobile communication terminal that generated the packet and is included only when there is a key input related to the game at the time of generating the packet.

The 32-bit checksum 1 is a part for checking whether there is an error in the time stamp 1 and the key input information 1 item, and can improve performance over the 16-bit checksum of the existing UDP packet.

The timestamp 2, the key input information 2, and the 32-bit checksum 2 portion are for the implementation of the failover algorithm described below.

The time stamp 2 includes time stamp information included in a time stamp 1 item of a UDP packet transmitted before a predetermined time.

The key input information 2 includes contents contained in the key input information 1 item of the packet generated at the time indicated in the time stamp 2.

The 32-bit checksum 2 is a part for checking whether there is an error in the time stamp 2 and the key input information 2 item, and can improve performance than the 16-bit checksum of the existing UDP packet.

The reason for sending and receiving a packet using UDP, which is a connectionless protocol, is that a packet is successfully transmitted after packet transmission when a packet is transmitted and received using a TCP protocol that is guaranteed in a network with a small bandwidth and an unstable state. This is because the game slows down too much because it has to go through the process of checking whether it is.

On the other hand, it is also possible to implement the present invention by building a new protocol corresponding to the UDP protocol including the information corresponding to the data portion of the UDP packet in the header portion.

5 is a flowchart illustrating a method for synchronizing a mobile network game according to an embodiment of the present invention.

First, a mobile network game is stored in a storage unit of a mobile communication terminal.

Referring to FIG. 5, the user executes a network game stored in the storage unit 304 of the first mobile communication terminal 300 (S100).

Thereafter, the first mobile communication terminal 300 receives time information from the time synchronization server 100 of the second mobile communication terminal 400 of the mobile network game partner connected through a remote network such as the Internet 500. The clock and the clock of the second mobile communication terminal 300 are synchronized (S102).

Thereafter, the first mobile communication terminal 300 includes timestamp information included in a packet that has received an initial packet transmission time and an initial packet reception time, and an application layer level of the second mobile communication terminal 400 of the game opponent. Based on the software ping time, that is, packet reciprocating time, the initial value of the buffer delay time, that is, the initial buffer delay time, is calculated based on the two values. In addition, the initial value of the packet transmission jitter indicating the instability of the network path for transmitting a packet from the first mobile communication terminal 300 to the second mobile communication terminal 400 of the game opponent, that is, the initial packet transmission jitter rate and The initial value of the packet reception jitter rate, that is, the initial packet reception jitter rate indicating the instability of the network path for transmitting a packet from the first mobile communication terminal 300 to the second mobile communication terminal 400 of the game opponent, is a reference value. It is set to 1 (S104).

Thereafter, the first mobile communication terminal 300 has a key input related to the game progress from the input unit 306 of the first mobile communication terminal 300 or the wireless communication unit 302 of the first mobile communication terminal 300. Receiving a packet including the key input information related to the game progress (S106), the key input information is reflected to the game after the initial buffer delay time from the key input of the key input to the first mobile communication. The display unit 308 outputs the terminal 300 (S108).

Further, the first mobile communication terminal 300 calculates the reset value of the packet transmission time, that is, the reset packet transmission time and the reset value of the packet reception time, that is, the reset packet reception time, and the initial packet transmission time and the initial packet reception time. Based on the reset packet transmission time, reset packet reception time, timestamp period, and human cognitive response time value, that is, reset packet transmission jitter rate, that is, reset packet transmission jitter and packet reception jitter Calculate packet reception jitter. Then, a reset buffer delay time based on the reset packet transmission time, the reset packet reception time, the reset packet transmission jitter rate, the reset packet reception jitter rate, the time spam period, and the basic overhead required for network transmission and information processing. Calculate the (S110).

Thereafter, as the speed of the network decreases, the first mobile communication terminal 300 speeds up the output of the packet to the game program rather than the speed of receiving the packet through the wireless communication unit 302, thus exhausting the buffer. It is determined whether or not (S112).

As a result of the determination of S112, when the buffer is exhausted, the process moves to step S104. When the buffer is exhausted, the reason for moving back to step S104 and recalculating the initial values is that the current network state becomes significantly slower and unstable than the initial value and reset values. This is to calculate the buffer delay time.

On the other hand, if it is determined in S112 that the buffer is not exhausted, it is determined whether the reset buffer delay value is larger than the afterimage effect time value which is a reverse threshold value (S114).

As a result of the determination in S114, when the reset buffer delay time is not greater than the afterimage effect time value of the reverse threshold value, the first mobile communication terminal 300 sets the reset buffer delay time to the reverse threshold value (S118). Go to step S120. The reason for setting the reset buffer delay time to the afterimage effect allowable time value, which is a reverse threshold value, is that the user may be used when one or two buffers are exhausted when the buffer delay time is set within the afterimage allowable time when the human being does not feel the disconnection of the output screen. This is because the game can proceed without feeling flickering on the screen.

The afterimage effect time is experimentally known as 0.0625 seconds.

As a result of the determination of S114, when the reset buffer delay time is larger than the afterimage effect allowable time value, which is a reverse threshold value, the first mobile communication terminal 300 determines whether the reset buffer delay time is a human threshold response time which is a forward threshold value. It is determined whether or not it is smaller (S116).                     

The average time value of human cognitive response is 0.64 seconds according to the research results of various scholars.

As a result of the determination of S116, when the reset buffer delay time is smaller than the average human cognitive response time value, the first mobile communication terminal 300 sets all the reset values as initial values (S120). Move on to step S106.

On the other hand, if it is determined in S116 that the reset buffer delay time is not smaller than the average human cognitive response time value, the first mobile communication terminal 300 applies a packet skip algorithm to the game within the forward threshold value. Skip the information that is not reflected in the game or proceed with a dead reckoning algorithm to infer the information not reflected in the game in the forward threshold value to reflect the game to proceed with the game (S117) and at the same time the S118 Go to step. In addition to the packet skipping algorithm or the dead reckoning algorithm, the game may be progressed by employing various algorithms to solve the case where the network condition is poor.

6 is a flowchart of a buffer time value calculation method according to the present invention.

First, a mobile network game is executed in the first mobile communication terminal 300.

Referring to FIG. 6, the first mobile communication terminal 300 receives the time information from the time synchronization server 200 and moves a second mobile opponent of the mobile network game connected through a remote network such as the Internet 500. The clock of the communication terminal 400 and the clock of the mobile communication terminal 300 are synchronized. In this process, the time synchronization server 200, the first mobile communication terminal 300, the second mobile communication terminal 400 of the game opponent while pinging the initial of the first mobile communication terminal 300 A packet transmission time and an initial packet reception time are obtained (S200). The method is a known method and detailed description thereof will be omitted herein.

Thereafter, the first mobile communication terminal 300 sets an initial packet transmission jitter rate and an initial packet reception jitter rate to 1, which is a reference value (S202), to calculate the initial packet transmission time and the initial packet reception time. Make it.

Thereafter, the first mobile communication terminal 300 calculates an initial buffer delay time based on the following equation (S204).

Td (n) = max (T1, T2) + Elim + min (T1, T2, Ov) + S

Where Td is the initial buffer delay time, T1 is the initial packet transmission time, T2 is the initial packet reception time, Elim is a preset reverse threshold value, S is the period of the timestamp, and Ov is the basic for the network and information processing. Is overhead.

Thereafter, the first mobile communication terminal 300 receives a packet relating to the game including timestamp information from the mobile communication terminal 400 of the game opponent, obtains the transmission and reception time of the packet, and receives the game. Send a software ping to the opponent's second mobile communication terminal 400 to obtain a ping time, that is, a time for the packet to return from the first mobile communication terminal 300 to the game's second mobile communication terminal 400. do. Based on the packet transmission, reception time and the ping time, the reset packet transmission time and the reset packet reception time are calculated based on Equations 1 and 2, respectively (S206).                     

Equation 1) T1 (n + 1) = Ts-T2 (n + 1)

Where T1 (n + 1) is the reset packet transmission time, Ts is the round trip time of the ping obtained by sending a software ping to the mobile communication terminal of the game, and T2 (n + 1) is the reset packet reception time.

Equation 2) T2 (n + 1) = Ta-Tu

Here, T2 (n + 1) is a reset packet reception time, Ta is a time when the packet is received by the mobile communication terminal, Tu is a time indicated by the time stamp included in the packet, that is, a time when the packet is transmitted.

Thereafter, the first mobile communication terminal 300 sets the reset packet transmission jitter rate and the reset packet reception jitter rate indicating the change of the network state after setting an initial value such as the speed of the network based on Equations 3 and 4, respectively. It calculates by (S208).

Equation 3) J1 (n + 1) = J1 (n) * (1-S / Elim) + [(T1 (n + 1) -T1 (n)) / T1 (n + 1)] * (S / Elim )

Where J1 (n + 1) is the reset packet transmission jitter, J1 (n) is the initial packet transmission jitter rate, T1 (n + 1) is the reset packet transmission time, T1 (n) is the initial packet transmission time, and S is the time The period of the stamp, Elim, is a preset reverse threshold.

Equation 4) J2 (n + 1) = J2 (n) * (1-S / Elim) + [(T2 (n + 1) -T2 (n)) / T2 (n + 1)] * (S / Elim )

Where J2 (n + 1) is the reset packet reception jitter rate, J2 (n) is the initial packet reception jitter rate, T2 (n + 1) is the reset packet reception time, T2 (n) is the initial packet reception time, and S is the time The period of the stamp, Elim, is a preset reverse threshold.

Thereafter, the first mobile communication terminal 300 determines whether the calculated reset packet transmission jitter rate or the reset packet reception jitter rate is less than two (S210).

That is, it is determined whether the network state is significantly slowed down after calculating the initial buffer delay time.

As a result of the determination of S210, when the calculated reset packet transmission jitter rate and the reset packet reception jitter rate are less than 2, the first mobile communication terminal 300 multiplies the initial packet transmission jitter rate by the initial packet transmission time. It is determined whether the packet reception jitter rate is greater than a value multiplied by the initial packet reception time (S214).

As a result of the determination of S214, when the value obtained by multiplying the initial packet transmission jitter rate and the initial packet transmission time is larger than the value obtained by multiplying the initial packet reception jitter rate and the initial packet reception time, the mobile communication terminal 300 is reset by Equation 5 below. After calculating the buffer delay time (S216), the process moves to step S218 to be described later.

Equation 5) Td (n + 1) = T1 (n + 1) * J1 (n + 1) + T1 (n + 1) * [J1 (n + 1) -1] + Elim + S + min (T1 ( n + 1) * J1 (n + 1), T2 (n + 1) * J2 (n + 1), Ov)

Where Td (n + 1) is the reset buffer delay time, T1 (n + 1) is the reset packet transmission time, J1 (n + 1) is the reset packet transmission jitter rate, Elim is the preset reverse threshold, S is the timestamp The period of, Ov is the basic overhead of the network and information processing.

On the other hand, when the result of the determination S214, if the value of the initial packet transmission jitter rate and the initial packet transmission time is not greater than the value of the initial packet reception jitter rate and the initial packet reception time, the mobile terminal 300 is expressed by Equation 6 After calculating the reset buffer delay time (S217), the process moves to step S218 to be described later.                     

Equation 5) Td (n + 1) = T2 (n + 1) * J2 (n + 1) + T2 (n + 1) * [J2 (n + 1) -1] + Elim + S + min (T1 ( n + 1) * J1 (n + 1), T2 (n + 1) * J2 (n + 1), Ov)

Where Td (n + 1) is the reset buffer delay time, T1 (n + 1) is the reset packet transmission time, J1 (n + 1) is the reset packet transmission jitter rate, Elim is the preset reverse threshold, and S is the time The period of the stamp, Ov, is the basic overhead of the network and information processing.

If the packet transmission jitter rate or the packet reception jitter rate is not less than 2, the first mobile communication terminal 300 determines whether the buffer is exhausted (S211).

If the buffer is not exhausted as a result of the determination of S211, the first mobile communication terminal 300 sets a value greater than 2 of the jitter rate to 2 (S213) and moves to step S214.

On the other hand, if the buffer is exhausted as a result of the determination of S212, the first mobile communication terminal 300 applies a packet skip or dead reckoning algorithm (S212) and proceeds to step S213.

Thereafter, as the speed of the network decreases, the first mobile communication terminal 300 determines whether the buffer is exhausted because the speed at which the packet is output to the game program is faster than the speed at which the packet is received through the wireless communication unit. (S218).

As a result of the determination of S218, when the buffer is exhausted, the flow proceeds to step S200. The reason for recalculating the initial values by moving to step S200 when the buffer is exhausted is based on the current network state as the current network state becomes considerably slower and unstable compared to the initial value and reset values. This is to calculate the initial buffer delay time.

On the other hand, if it is determined in S218 that the buffer is not exhausted, it is determined whether the reset buffer delay value is greater than the afterimage effect time value, which is a reverse threshold value (S220).

As a result of the determination in S220, when the reset buffer delay time is not greater than the afterimage effect time value, which is a reverse threshold value, the first mobile communication terminal 300 sets the reset buffer delay time as a reverse threshold value (S224). It moves to step S226 below.

As a result of the determination in S220, when the reset buffer delay time is greater than the afterimage effect time value of the reverse threshold value, it is determined whether the reset buffer delay time is human or less than the response average time value of the forward threshold value (S222).

As a result of the determination in S222, when the reset buffer delay time is smaller than the human cognitive response average time value, which is a forward threshold value, all reset values are set as initial values (S226), and then the process proceeds to step S206.

On the other hand, if it is determined in S222 that the reset buffer delay time is not smaller than the average human cognitive response time value, the packet skip algorithm is applied to skip the information not reflected in the game in the forward threshold value and play the game. By proceeding or applying a dead reckoning algorithm infers the information that is not reflected in the game in the forward threshold value to reflect the game proceeds to the game (S223) and at the same time moves to step S226. In addition to the packet skip algorithm or the dead reckoning algorithm, the game may be performed by using various algorithms for solving a bad network condition.

7 is a flowchart illustrating a fault overcoming method according to the present invention.

Referring to FIG. 7, the first mobile communication terminal 300 undergoing a mobile network game includes an original including a time stamp, key input information, and a 32-bit checksum from the second mobile communication terminal 400 of the game opponent. Receive a UDP packet (S300).

Thereafter, the first mobile communication terminal 300 is connected to the mobile communication terminal within a time corresponding to half of the buffer delay time calculated by the mobile communication terminal of the game opponent from the second mobile communication terminal 400 of the game opponent. The contents of time stamp 1 and key input information 1 shown in FIG. 4 of the original UDP packet transmitted at the packet retransmission time Tr estimated to arrive are included in the time stamp 2 and key input information 2 shown in FIG. 4, respectively. A copy UDP packet is received (S302).

Thereafter, the controller 310 of the first mobile communication terminal 300 determines whether or not there is an error in the original UDP packet by a 32-bit checksum 1 included in the original UDP packet (S304).

As a result of the determination of S304, if there is an error in the original UDP packet, it is determined whether a copy UDP packet for the original UDP packet exists in the buffer (S306).

As a result of the determination in S304, when a copy UDP packet for the original UDP packet exists in the buffer, it is determined by the 32-bit checksum 2 included in the copy UDP packet whether or not there is an error in the copy UDP packet (S308).

As a result of the determination in S308, when there is no error in the copy UDP packet, the contents of the time stamp 1 and the key input information 1 of the original UDP packet in error are included and the contents of the time stamp 2 and the key input information 2 of the copy UDP packet. Replace it to reflect the game and end the procedure. (S310).

On the other hand, if it is determined in S308 that there is an error in the copy UDP packet, the related key input information lost is resolved by packet skipping or dead reckoning algorithm without reflecting the packet in the game and the procedure is terminated (S309).

As a result of the determination of S308, if there is no error in the original UDP packet, the original UDP packet is reflected in the game and the procedure is terminated (S312).

8A and 8B are flowcharts illustrating a repetitive transmission method of a UDP datagram according to the present invention.

Referring to FIGS. 8A and 8B, about 1% of UDP packet errors are detected in an ADSL network environment. In order to improve such a packet error, a repetitive transmission method is adopted in addition to the 32-bit checksum in the UDP packet.

When the packet is retransmitted at regular intervals, when the error is detected through the 32-bit checksum, it is possible to implement a game incessantly by obtaining a reliable packet in the copy UDP packet without requiring retransmission. Theoretically, the probability of UDP packets going through an error is greatly reduced to 1% * 1% = 0.01%.

In case of repetitive transmission, there may be a concern that the amount of UDP packets is doubled and inefficient. However, since only the key input information is transmitted and received, it does not cause any problem because it occupies almost no bandwidth of the network.                     

As shown in FIG. 8A, the first mobile communication terminal 300 executing the mobile network game transmits the original UDP packet, and after a predetermined retransmission time passes, the second mobile communication terminal 400 of the game opponent. Send a copy UDP packet. The retransmission time is calculated as the time that can reach the second mobile communication terminal within half of the buffer delay time calculated by the first mobile communication terminal 300. In this case, it is because the second mobile communication terminal 400 can receive the copy UDP packet within the buffer delay time even when the network transmission becomes unstable after the packet transmission and the packet transmission jitter becomes 2.

As shown in FIG. 8B, when the network condition is improved after transmitting the original UDP packet, the copy UDP packet arrives at the second mobile communication terminal within the buffer delay time to implement a seamless game.

The present invention is of course not limited to mobile network games, but can be applied to other computer network games.

The present invention is not limited to the embodiments described above, and various modifications and changes can be made by those skilled in the art, which are included in the spirit and scope of the present invention as defined in the appended claims.

According to the present invention as described above, in order to synchronize the network game that is being progressed in the various remote terminals, only the key input related to the game can be synchronized to improve the speed of the game.                     

In addition, according to the present invention as described above, the amount of information transmitted through the network for the synchronization of the game is reduced, thereby increasing the capacity of the entire network.

In addition, according to the present invention as described above, by providing an SDK (system development kit) and API (application program interface) for implementing the algorithm there is an effect that can simplify the game development.

Claims (31)

A first step of calculating a buffer delay time for compensating for a signal transmission delay occurring in a network from time stamp information included in a connectionless protocol packet received from a mobile communication terminal of a game opponent connected through a network; If there is a first key input by the user to proceed with the game, the second key included in the connectionless protocol packet received from the terminal of the game by delaying the information corresponding to the key input by the calculated buffer delay time. A second step of synchronizing with information corresponding to the input and outputting the same to the game in progress; Input / output-based game synchronization method of a network game comprising a. The method of claim 1, wherein before the first step A first packet transmission step of periodically transmitting a connectionless protocol packet including time stamp information to a mobile network game opponent terminal; A second packet transmission step of transmitting a connectionless protocol packet including the time stamp information and the corresponding key input information to a mobile communication terminal of the game opponent when there is any key input for proceeding with the game; Input / output-based game synchronization method of a network game, characterized in that it further comprises. The method according to claim 2, for failover of packets due to loss of packets during transmission on a network. I / O-based game synchronization method of the network game, characterized in that for retransmitting the packet after a predetermined time from the transmission of the arbitrary connectionless protocol packet. The method of claim 2, wherein the first packet transmission step After executing the mobile network game, the initial packet transmission time and the game required to receive the time information from the time synchronization server to synchronize the clock with the mobile communication terminal of the game opponent to send packets to the mobile communication terminal of the game opponent Obtaining an initial packet reception time required to receive a packet from a counterpart mobile communication terminal, and calculating an initial buffer delay time based on the obtained initial packet transmission time and the initial packet reception time; Input / output-based game synchronization method of a network game, characterized in that it further comprises. The input / output-based game synchronization method of claim 2, wherein the initial buffer delay time is obtained based on the following equation. Td = max (T1, T2) + Elim + min (T1, T2, Ov) + S (However, Td is the initial buffer delay time, T1 is the initial packet transmission time, T2 is the initial packet reception time, Elim is the preset reverse threshold value, S is the time stamp period value, and Ov is the basic overload for network and information processing. head) The method according to claim 2, wherein the first packet transmission step, Initial packet transmission jitter rate indicating the stability of the network path for transmitting packets to the mobile communication terminal of the game opponent and initial packet reception indicating the stability of the network path for receiving packets from the mobile communication terminal of the game opponent Setting the jitter rate as a reference value; Input / output-based game synchronization method of a network game, characterized in that it further comprises. The method of claim 1, wherein the first step calculates a reset packet transmission time, a reset packet reception time, a reset packet transmission jitter rate, a reset packet reception jitter rate changed from an initial value, and reset buffer delay time based on the calculated values. I / O-based game synchronization method of a network game, characterized in that for calculating. The method according to claim 7, wherein the reset packet transmission time, reset packet reception time, reset packet transmission jitter rate, reset packet reception jitter rate is obtained according to the following equations (1), (2), (3) and (4), respectively. I / O based game synchronization method for network games. Equation 1) T1 (n + 1) = Ts-T2 (n + 1) Equation 2) T2 (n + 1) = Ta-Tu Equation 3) J1 (n + 1) = J1 (n) * (1-S / Elim) + [(T1 (n + 1) -T1 (n)) / T1 (n + 1)] * (S / Elim ) Equation 4) J2 (n + 1) = J2 (n) * (1-S / Elim) + [(T2 (n + 1) -T2 (n)) / T2 (n + 1)] * (S / Elim ) (Where T1 (n + 1) is the reset packet transmission time, T2 (n + 1) is the reset packet reception time, Ts is the software ping round trip time obtained by sending a software ping to the mobile communication terminal of the game, Ta is The time at which the packet is received at the mobile communication terminal, Tu is the time indicated by the time stamp included in the packet, J1 (n) is the initial packet transmission jitter, J2 (n) is the initial packet reception jitter, J1 (n + 1) is the reset packet transmission jitter rate, J2 (n + 1) is the reset packet reception jitter rate, S is the period of timestamp, and Elim is the preset reverse threshold value.) The method according to claim 7, A reset jitter determination step of determining whether the reset packet transmission jitter rate or the reset packet reception jitter rate is greater than a preset threshold; Determining whether the buffer is exhausted when the reset packet transmission jitter rate or the reset packet reception jitter rate is greater than a preset threshold; A jitter resetting step of setting a larger value of the reset jitter rate as the threshold value when the buffer is not exhausted as a result of the determination; Input / output-based game synchronization method of a network game, characterized in that it further comprises. 10. The method of claim 9, wherein if the buffer is exhausted after determining whether the buffer is exhausted, the game is played by applying a packet skip or dead reckoning method. The method according to claim 7 or 8, wherein the reset buffer delay time is based on Equation 1) when the value obtained by multiplying the initial packet transmission jitter rate and the initial packet transmission time is larger than the value of the initial packet reception jitter rate and the initial packet reception time. , If it is not large, the input and output game synchronization method of the network game, characterized in that by the following equation 2). 1) Td (n + 1) = T1 (n + 1) * J1 (n + 1) + T1 (n + 1) * [J1 (n + 1) -1] + Elim + S + min (T1 ( n + 1) * J1 (n + 1), T2 (n + 1) * J2 (n + 1), Ov) 2) Td (n + 1) = T2 (n + 1) * J2 (n + 1) + T2 (n + 1) * [J2 (n + 1) -1] + Elim + S + min (T1 ( n + 1) * J1 (n + 1), T2 (n + 1) * J2 (n + 1), Ov) (Where Td (n + 1) is the reset buffer delay time, T1 (n + 1) is the reset packet transmission time, T2 (n + 1) is the reset packet reception time, and J1 (n + 1) is the reset packet transmission jitter Rate, J2 (n + 1) is the reset packet reception jitter rate, Elim is the preset reverse threshold value, S is the period of timestamp, Ov is the basic overhead for network and information processing) The method of claim 1, wherein after the second step A buffer exhaustion determining step of determining whether the buffer is exhausted; A reverse threshold value contrast step of determining whether the reset buffer delay time is greater than a preset reverse threshold value when the buffer is exhausted as a result of the determination; If the reset buffer delay time is larger than the reverse threshold value, determining whether the reset buffer delay time is smaller than a predetermined forward threshold value; A regression step of moving to the second step if the reset buffer delay time is smaller than the forward threshold value as a result of the determination; Input / output-based game synchronization method of a network game, characterized in that it further comprises. The method of claim 12, wherein the reset buffer delay time is set to a reverse threshold value when the reset buffer delay time is not greater than the reverse threshold value. The I / O-based game of a network game according to claim 12, wherein when the reset buffer delay time is not smaller than the forward threshold value, a packet skip or dead reckoning method is applied and the game proceeds to the second step. Synchronization method. The method of claim 1, wherein the packet is A first timestamp including generation time information of the packet, first key input information including key input information at the time of packet generation, a first 32-bit checksum for the first time stamp, and the first key input information Original section containing the information, A second timestamp including a first timestamp of a packet generated before a predetermined time from the generation of the packet, second key input information including first key input information of a packet generated before the predetermined time, and And a copy unit including a second timestamp and second 32-bit checksum information with respect to the second key input information. The method according to claim 15, Receiving, after a predetermined time, a second packet including an original part of the received first packet; Determining whether there is an error in the first packet based on first 32-bit checksum information of the first packet; Determining whether the second packet exists in the buffer when the first packet has an error as a result of the determination; If the second packet exists in the buffer as a result of the determination, determining whether the second packet has an error based on second 32-bit checksum information included in the second packet; If there is no error in the second packet, replacing the first time stamp and first key input information of the first packet with a second time stamp and second key input information of the second packet; Input / output-based game synchronization method of a network game, characterized in that it further comprises. The method according to claim 14, wherein if the second packet has an error as a result of the determination, the game is played by applying a dead reckoning or a packet skip method. A storage unit for storing a program for running a network game; An input unit configured to receive data regarding the progress of the game; A display unit which displays the progress of the game; Calculate a buffer delay time for compensating for a signal propagation delay occurring on a network from time stamp information included in a connectionless protocol packet received from a mobile communication terminal of a game opponent connected through a network and providing a user's information to proceed with a game. When there is one key input, the information corresponding to the key input is delayed by the calculated buffer delay time to synchronize with the information corresponding to the second key input included in the connectionless protocol packet received from the terminal of the game opponent. A controller for controlling the output to the game in progress; Mobile communication terminal for input / output based game synchronization of a network game comprising a. 19. The apparatus of claim 18, wherein the controller periodically transmits a connectionless protocol packet including timestamp information to a mobile network counterpart terminal, and if there is any key input for proceeding with the game, the timestamp information and the corresponding key input. A mobile communication terminal for input / output based game synchronization of a network game, characterized by transmitting a connectionless protocol packet including information to the terminal of the game opponent. 20. The network game of claim 19, wherein the controller controls the packet to be retransmitted after a predetermined time elapses from when the random connectionless protocol packet is transmitted to overcome a failure due to the loss of the packet during transmission on the network. Mobile communication terminal for I / O based game synchronization. 20. The method of claim 19, wherein after executing the mobile network game, the controller receives time information from a time synchronization server, synchronizes a clock with the mobile communication terminal of the game partner, and transmits the packet to the mobile communication terminal of the game opponent. An initial packet transmission time and an initial packet reception time required to receive a packet from the mobile communication terminal of the game opponent, and an initial buffer delay time based on the obtained initial packet transmission time and the initial packet reception time. Mobile communication terminal for the input and output game synchronization of the network game, characterized in that the control to calculate. The network of claim 19, wherein the controller receives an initial packet transmission jitter rate indicating a stability of a network path for transmitting a packet to the mobile communication terminal of the game opponent, and a network for receiving a packet from the mobile communication terminal of the game opponent. A mobile communication terminal for I / O-based game synchronization of a network game, characterized by controlling to set an initial packet reception jitter rate indicating a path stability as a reference value. 20. The apparatus of claim 19, wherein the controller calculates a reset packet transmission time, a reset packet reception time, a reset packet transmission jitter rate, a reset packet reception jitter rate changed from an initial value, and calculates a reset buffer delay time based on the calculated values. A mobile communication terminal for input / output based game synchronization of a network game, characterized in that the control to control. 24. The method of claim 23, wherein the controller determines whether the reset packet transmission jitter rate or the reset packet reception jitter rate is greater than a preset threshold, and as a result of the determination, the reset packet transmission jitter rate or the reset packet reception jitter rate is preset. If it is greater than the threshold value, it is determined whether or not the buffer is exhausted, and if the buffer is not exhausted as a result of the determination, controlling to set a larger value than the threshold value among the reset jitter rate as a threshold value. Mobile communication terminal for input / output based game synchronization. 25. The I / O-based game synchronization of a network game according to claim 24, wherein the controller determines whether the buffer is exhausted and controls to proceed with the game by applying a packet skip or dead reckoning method when the buffer is exhausted. Mobile communication terminal for. 20. The method of claim 19, wherein the controller determines whether the buffer is exhausted, and when the buffer is exhausted as a result of the determination, the controller determines whether the reset buffer delay time is greater than a preset reverse threshold value, and the reset buffer delay time is determined. If it is larger than the reverse threshold value, it is determined whether the reset buffer delay time is smaller than the predetermined forward threshold value. If the reset buffer delay time is smaller than the forward threshold value, the reset buffer delay time is set as the initial buffer delay time. Mobile communication terminal for input and output game synchronization of the network game, characterized in that the control to set. 27. The method of claim 26, wherein when the reset buffer delay time is not greater than the reverse threshold value, after setting the reset buffer delay time to a reverse threshold value, and setting the reset buffer delay time to an initial buffer delay time. A mobile communication terminal for input / output based game synchronization of a network game, characterized in that the control to control. 27. The method of claim 26, wherein when the reset buffer delay time is not less than the forward threshold value, the controller controls to proceed with a game by applying a packet skip or dead reckoning method and to set the reset buffer delay time as an initial buffer delay time. Mobile communication terminal for input and output game synchronization of the network game, characterized in that. 19. The method of claim 18, wherein the packet includes a first timestamp including generation time information of the packet, first key input information including key input information when the packet is generated, the first timestamp and the first key input. A second timestamp including a source portion including first 32-bit checksum information for the information, a first timestamp of a packet generated a predetermined time before the packet is generated, and a packet generated before the predetermined time And a copy unit including second key input information including first key input information of the second key stamp, second copy of the second time stamp and second 32 bit checksum information of the second key input information. Mobile terminal for game synchronization. 30. The method of claim 29, wherein the control unit receives a second packet including the original portion of the received first first packet after a predetermined time and based on the first 32-bit checksum information of the first packet It is determined whether there is an error in the first packet, and if it is determined that the first packet has an error, it is determined whether the second packet exists in the buffer, and the determination result exists in the buffer. If it is determined that there is an error in the second packet, based on the second 32-bit checksum information included in the second packet, and if the second packet has no error, the first packet of the first packet is determined. I / O-based game synchronization of the network game, characterized in that the control to replace the first time stamp and the first key input information with the second time stamp and the second key input information of the second packet. Mobile communication terminal. 30. The mobile communication terminal of claim 29, wherein the controller controls to proceed with a game by applying a dead reckoning or a packet skip method when the second packet has an error.

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