KR100704845B1 - Method And System for Providing Connection Admission Control for Use in Portable Internet - Google Patents

Abstract

The present invention relates to a call admission control method and system in a portable Internet system.

The present invention relates to a system for performing call admission control in a portable Internet system, comprising: a RT-VR (Real Time Access) that includes a Video On Demand (VOD) and a Music On Demand (MOD) from a packet data server connected to the portable Internet system. It is equipped with a mobile internet platform that receives and uses a Best-Effort (BE) service including time-variable rate service, file download, and web browsing, and runs various applications. A portable internet terminal having a browser for internet access; A wireless access network that transmits and receives a signal wirelessly with the portable Internet terminal and performs handoff and wireless resource management functions of the portable Internet terminal; An edge router (ER) for managing a session to provide a packet data service and relaying transmission and reception of packet data between the packet data server and the wireless access network; A home agent (HA) for routing the packet data transmitted from the packet data server connected to a network including the Internet; An AAA (Authentication, Authorization, Accounting) for performing charging for the packet data used in the portable Internet terminal in connection with the ER and authenticating a connection from the portable Internet terminal; A backbone network interconnecting the ER, the HA, and the AAA, receiving the packet data from the external packet data server, and transmitting the packet data to the wireless access network; And a content server that accesses the portable internet system and requests a multimedia service including a video service by searching for a stored database and providing the packet data to the portable internet terminal. The access network measures a Video Packet Buffer Empty Ratio (VER), which is a ratio in which the buffers of the portable Internet terminals corresponding to the RT-VR service are empty among the currently available portable Internet terminals. A call admission control system is provided in a portable Internet system characterized by accepting a new call only when the buffer vacancy rate can be maintained below a predetermined value.

According to the present invention, a call admission control method for classifying and estimating various resources occupied by a service request or a call by traffic type satisfies QoS of RT-VR service and BE service and efficiently manages radio resources. Improve the quality of service In the case of a system supporting mobility, a seamless service can be received even when moving by packet scheduling considering handoff. In addition, according to the present invention, it is possible to reduce the investment cost by increasing the efficiency of the system.

Mobile Internet, Wibro, Call Admission Control, Packet Scheduler, QoS

Description

Method and System for Providing Connection Admission Control for Use in Portable Internet}

1 is a view schematically showing a portable internet system according to a preferred embodiment of the present invention;

2 is a flowchart illustrating a call admission control method for guaranteeing a quality of service of a portable Internet system according to an embodiment of the present invention;

3 is a flowchart illustrating a packet scheduling method for guaranteeing a quality of service of a portable Internet system according to an exemplary embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

110: portable internet terminal 120: wireless access network

122: radio access station 124: access control router

130: edge router 140: backbone network

142: home agent 144: authentication server

150: content server

The present invention relates to a call admission control method and system in a portable Internet system. More specifically, to maximize the system performance in the portable Internet system, to efficiently manage the radio resources of the system in order to guarantee the QoS of the main service types RT-VR service and BE service, and to consider the hand-off when moving The present invention relates to a call admission control method and system for guaranteeing a service quality of a portable Internet system in consideration of system characteristics and provided service characteristics in order to provide a seamless service.

With the rapid development of computer, electronic and communication technologies, various wireless communication services using a wireless network have been provided. The most basic wireless communication service is a wireless voice call service that provides a voice call to a mobile terminal user wirelessly, which can provide a service regardless of time and place. In addition, while supplementing a voice call service by providing a text message, a wireless Internet service has recently emerged, which provides an Internet service to a user of a mobile communication terminal through a wireless communication network.

As a result of the development of communication technology, a service provided by a code division multiple access (CDMA) system is not only a voice service but also a multimedia communication service that transmits data such as circuit data and packet data. Is developing.

In recent years, IMT-2000 (International Mobile Telecommunication 2000), a third generation mobile communication system that has been established as a standard by ITU-R due to the development of information and communication, has been commercialized.

However, the existing mobile communication system is expensive to use the base station because of the high base station construction cost, and because the screen size of the mobile communication terminal is limited to provide high-speed wireless Internet, such as limited content available. In addition, wireless local area network (WLAN) technology has limitations in providing it as a public service due to problems such as radio wave interference and narrowness of coverage. As a result, a mobile Internet (Wibro: Wireless Broadband Internet or PI: Portable Internet) system that can use a high-speed wireless Internet service at a low price while moving has emerged.

The portable internet system can use various types of information and contents by accessing the internet in indoor and outdoor stationary environments and mobile environments of walking speed and low to medium speed using various types of portable internet terminals such as laptops, PDAs and handheld PCs. It is a service. In addition, it provides mobility of 60 km / h per hour, and has a downlink transmission speed of 24.8 Mbps, but an uplink transmission speed of 5.2 Mbps, which is an IP (Internet Protocol) based wireless data system having up and down asymmetric transmission characteristics.

In addition, the mobile Internet system uses a 2.3 GHz frequency band, and in order to effectively use the allocated frequency spectrum, a time division duplex (TDD) is drawn by a duplex method, and a multiple access method is used. Uses Orthogonal Frequency Division Multiple Access (OFDMA).

With the advent of such a portable Internet system, a higher quality internet service than the existing CDMA2000 1x and 1x EV-DO is possible, and various kinds of internet services will be provided based on this.

Representative mobile internet services include real-time (RT-VR) services represented by streaming video (RT-VR), HTTP (Hypertext Transfer Protocol) and FTP (File Transfer Protocol). ) And Non Real Time Best Effort (BE) service. RT-VR services, such as Video On Demand (VOD) and Music On Demand (MOD), which cause a large amount of data traffic, are sensitive to delay and jitter, resulting in interruptions or low quality video or audio. Serviced. In contrast, BE services such as file downloads and web browsing are relatively unaffected by time lag.

Due to the characteristics of these services, in the multimedia communication system in which the RT-VR service and the BE service coexist, it is common to transmit the RT-VR service with a higher priority than the BE service among the calls already accepted with each portable Internet terminal.

Connection Admission Control, which operates at the stage of determining whether to establish a connection, prevents the base station from serving more terminals than the terminal currently providing services, or provides current services to provide more terminals. If it is estimated that serious adverse effects on the performance of the terminals receiving the overall or the base station performance will be degraded, it is common to reject the request of the new terminals requesting service. In the case of circuit service, since the amount of resources used by each terminal is constant, in order to accept a new request or call, the number of service calls simply needs to be kept lower than the total number of service calls. However, due to the rapid increase of mobile Internet users and the provision of various services, the types of resources occupied by calls have to be diversified.

On the other hand, when a base station needs to transmit downlink traffic to a plurality of mobile communication terminals or when a plurality of mobile communication terminals need to transmit uplink traffic to a base station, the base station should determine the transmission priority. This role is called the packet scheduler.

Conventional packet scheduling methods give unconditional priority to real-time services over non-real-time services. This method can guarantee the quality of real-time service, but can cause excessive packet delay of non-real-time service quality. Since the concept of real time means that the processing should be completed within a predetermined 'time limit', the performance of the entire system can be improved by scheduling while giving appropriate relative priority to the non-real time service if there is a margin up to the predetermined limit. By adjusting the relative size of the priority of real-time traffic according to the constantly changing traffic or transmission situation, there is a need to increase the quality of non-real-time service while maintaining the time limit of the real-time service. Therefore, there is a need to design a packet scheduling method that varies according to channel quality, video buffer status of a portable Internet terminal without fixing the packet transmission priority of the RT-VR service.

In addition, the portable Internet system supports both fixed users and high-speed mobile users of more than 60 km / h. In addition, since a high system capacity is required to provide a multimedia service, a small cell is usually used. In other words, the portable Internet system should operate even in an environment in which a user moves at a high speed and transfers data between relatively small cells. In this case, since handoff occurs frequently, the performance at the time of handoff greatly affects the overall performance. An efficient handoff must be able to handle the handoff procedure quickly and the resource allocation for the handoff must be efficient. So we need a packet scheduler that allocates resources efficiently during handoff.

In order to solve the above problems, the present invention, to maximize the system performance in the portable Internet system, to efficiently manage the radio resources of the system to ensure the QoS of the main service type RT-VR service and BE service, hand It is an object of the present invention to provide a call admission control method and system for guaranteeing a service quality of a portable Internet system in consideration of system characteristics and provided service characteristics in order to provide a seamless service even when mobile is considered.

In order to achieve the above object, the present invention provides a system for performing call admission control in a portable Internet system, which is connected to the portable Internet system and is provided with a Video On Demand (VOD) and a Music On Demand (MOD) from a packet data server. RT-VR (Real Time-Variable Rate) service and the BE (Best Effort) service including file download and web browsing are provided and used, and is equipped with a mobile Internet platform to drive a variety of applications (Application), A portable internet terminal including a portable internet access browser for accessing the portable internet; A wireless access network that transmits and receives a signal wirelessly with the portable Internet terminal and performs handoff and wireless resource management functions of the portable Internet terminal; An edge router (ER) for managing a session to provide a packet data service and relaying transmission and reception of packet data between the packet data server and the wireless access network; A home agent (HA) for routing the packet data transmitted from the packet data server connected to a network including the Internet; An AAA (Authentication, Authorization, Accounting) for performing charging for the packet data used in the portable Internet terminal in connection with the ER and authenticating a connection from the portable Internet terminal; A backbone network interconnecting the ER, the HA, and the AAA, receiving the packet data from the external packet data server, and transmitting the packet data to the wireless access network; And a content server that accesses the portable internet system and requests a multimedia service including a video service by searching for a stored database and providing the packet data to the portable internet terminal. The access network measures a Video Packet Buffer Empty Ratio (VER), which is a ratio in which the buffers of the portable Internet terminals corresponding to the RT-VR service are empty among the currently available portable Internet terminals. A call admission control system is provided in a portable Internet system characterized by accepting a new call only when the buffer vacancy rate can be maintained below a predetermined value.

In addition, according to another object of the present invention, even after accepting a new call in the portable Internet system, the system usage rate does not exceed the preset system usage rate, and RT-VR (Real Time-Variable Rate) among the currently available portable Internet terminals. A mobile Internet system that accepts the new call when the video packet buffer empty ratio (VER) of the mobile Internet terminals corresponding to the service can be maintained below a preset VER value. A call admission control method for guaranteeing a quality of service, the method comprising: (a) calculating an average of the VERs of the mobile Internet terminals provided with a service in the mobile Internet system; (b) It is determined whether there is a request for connection of the new call, and when there is a request, the system utilization rate and the resource requirement estimate of the new call are calculated, and the system utilization rate and the estimated resource utilization rate of the system at the time of call acceptance are calculated using the resource requirement estimate of the new call. Calculating; (c) reject the acceptance of the new call if the estimated utilization of the system at the time of call acceptance is greater than the system utilization parameter by comparing the estimated utilization of the system at the time of call acceptance with a predefined system utilization parameter; Calculating an Exponentially Weighted Video Packet Buffer Empty Ratio (EWVER) if the estimated utilization rate of the system upon acceptance is less than or equal to the system utilization parameter; And (d) comparing the EWVER with a predefined VER parameter for each service type, if the EWVER is greater than the VER parameter, rejecting the acceptance of the new call, and if it is less than or equal to, accepting the new call. Provided is a call admission control method in a portable internet system.

delete

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are used as much as possible even if displayed on different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

1 is a view schematically showing a portable internet system according to a preferred embodiment of the present invention.

In accordance with a preferred embodiment of the present invention, a portable Internet system includes a portable Internet terminal 110, a wireless access network 120, a radio access station (RAS) 122, and an access control router. ACR: Access Control Router (hereinafter referred to as 'ACR') 124, Edge Router (ER: Edge Router, hereinafter referred to as 'ER') 130, Backbone network 140, Home Agent (HA: Home Agent, Hereinafter referred to as 'HA' 142, an authentication server (AAA: Authentication, Authorization, Accounting, hereinafter referred to as 'AAA') 144 and a content server 150.

The portable Internet terminal 110 according to an embodiment of the present invention is a notebook computer, a PDA (Personal Digital Assistant), a cellular (Cellular) phone, a PCS (Personal Communication Service) phone, a handheld PC (Hand-Held Personal) Computer), Global System for Mobile (GSM) phones, Mobile Broadband System (MBS) phones, and the like. MBS phone refers to a mobile phone to be used in the fourth generation system currently being discussed.

The mobile Internet terminal 110 not only makes a phone call with the other party through a mobile communication network by wireless communication, but also accesses the mobile Internet system and connects the video on demand (VOD) or the music on demand (MOD) from the content server 150. It is a terminal that receives and receives the RT-VR (Real Time-Variable Rate) service and BE (Best Effort) service such as file download or web browsing. The portable internet terminal 110 includes a portable internet platform for driving portable internet related applications, and has a built-in browser for accessing the portable internet.

The wireless access network 120 transmits and receives a signal wirelessly with the portable internet terminal 110 and performs handoff and wireless resource management functions of the portable internet terminal 110.

The radio access network 120 includes a RAS 122 and an ACR 124.

The RAS 122 is a base station of the portable Internet system, and wirelessly transmits data received from the ACR 124 to the portable Internet terminal 110, and provides a low power RF / IF module and controller function, OFDMA / TDD packet scheduling and channel multiplexing. It has call admission control function, 50 Mbps high-speed traffic real-time control function, handoff function according to function, service characteristics and propagation environment. The ACR 124 is a packet access router that accommodates a plurality of RAS 122 and connects the RAS 122 with each other. The handoff control function between the RAS 122, the handoff control function between the ACR 124, the packet routing function, It has a connection management function and the like, and is connected to the Beckbone network 140 through the ER 130.

The ER 130 relays the transmission and reception of the packet data to perform both the upper and lower interfaces through the wireless communication through the IP so that the data can be serviced wirelessly.

The backbone network 140 connects the ER 130, the content server 150, the HA 142, the AAA 144, and the like, and receives the packet data from an external packet data service such as the Internet. To the ACR 124.

The HA 150 performs routing for transmitting a packet transmitted from an external packet data service server such as the Internet, and the AAA 160 interworks with the ER 130 to transmit packet data used by the portable Internet terminal 110. Charges for and authenticates the connection from the portable Internet terminal 110.

When the mobile internet terminal 110 requests various multimedia services including a video service by accessing the mobile internet system, the content server 150 searches the stored database and provides data to the mobile internet terminal 110. Here, the multimedia service refers to providing information such as news, weather, maps and travel as well as entertainment services such as movies, music, music videos, and dramas by video and voice.

2 is a flowchart illustrating a call admission control method for guaranteeing a service quality of a portable Internet service according to an exemplary embodiment of the present invention.

In the call admission control method proposed by the present invention, the RAS 122 continuously checks the video packet buffer empty ratio (VER) of all the mobile Internet terminals 110 in service. Figure out. The RAS 122 may receive its own state from each terminal and calculate the VER based on this.

프레임마다 RT-VR 서비스의 휴대인터넷 단말기(110)들의 VER 평균을 계산한다. k번째 프레임의 VER 평균

를 수학식 1을 이용하여 계산한다(S210).The RAS 122 divides the total system time into slots of a certain length in order to calculate the VER and represents the time using the slot number. Every cycle defined by RAS 122

The VER average of the mobile Internet terminals 110 of the RT-VR service is calculated for each frame. VER mean of kth frame

Is calculated using Equation 1 (S210).

는 RAS(120)가 서비스하는 휴대인터넷 단말기(110)의 총 수를 나타낸다. 각 프레임에서, RAS(122)는 휴대인터넷 단말기(110)의 버퍼가 비어있는지 확인할 수 있는데,

는 k개의 프레임 중에 휴대인터넷 단말기 i의 버퍼가 비어있는 것으로 RAS(122)가 확인한 프레임의 수이다.

Represents the total number of mobile Internet terminals 110 serviced by the RAS 120. In each frame, the RAS 122 may check whether the buffer of the mobile Internet terminal 110 is empty.

Is the number of frames that the RAS 122 determines that the buffer of the portable Internet terminal i is empty among k frames.

를 사용하여 수학식 2를 이용해 계산한다(S230).In operation S220, if there is a request for a call, the RAS 122 weights the current system utilization.

Calculate using Equation 2 using (S230).

는 호의 요청이 있는 프레임 t 동안 전송 트래픽으로 사용된 RA(Resource Allocation) 유닛의 수이고,

은 프레임 t 동안 RA 유닛의 총 수를 나타낸다.

Is the number of Resource Allocation (RA) units used as transport traffic during frame t upon request of the call,

Denotes the total number of RA units during frame t.

을 수학식 3을 이용하여 계산한다(S240). 가중치는 단계 S230에서와 같다.Next, the RAS 122 estimates the resources required for the new call for each service type (HTTP: Hypertext Transfer Protocol, FTP: File Transfer Protocol, Video) in every frame. Resource Requirements Estimates for New Issues

It is calculated using Equation 3 (S240). The weight is the same as in step S230.

는 프레임 t 동안 각 서비스 영역의 전송 트래픽으로 사용된 RA 유닛의 수이고,

는 프레임 t 동안 각 서비스 영역의 트래픽을 수신한 휴대인터 넷 단말기(110)의 수이다.

Is the number of RA units used as transport traffic of each service area during frame t,

Is the number of portable Internet terminals 110 that have received traffic in each service area during frame t.

를 수학식 4를 이용하여 계산한다(S250).The RAS 122 then calculates the utilization of the system after the call is accepted. Estimated utilization of system at call acceptance

Is calculated using Equation 4 (S250).

은 단계 S230의 프레임 t 동안 RA 유닛의 총 수이고,

는 단계 S240의 신규 호의 자원 소요 추정치이다.

Is the total number of RA units during frame t of step S230,

Is the resource requirement estimate of the new call of step S240.

와 비교하여(S260), 호 수락 후의 시스템 사용률이

보다 클 경우는 호 수락을 거절한다(S292).And the RAS 122 is a parameter defined in advance in the call admission control method of the present invention the estimated utilization rate at the time of call acceptance

Compared with (S260), the system utilization rate after call acceptance is

If greater, the call is rejected (S292).

를 넘지 않도록 하여 시스템의 효율성을 항상 설정된 수준 이상으로 유지하는 것이다.That is, the RAS 122 sets a value for the system load even after accepting a new call.

The efficiency of the system is always kept above the set level by not exceeding.

가

보다 작거나 같을 경우, 최근의 버퍼 공실율에 좀더 큰 가중치를 두기 위해 가중치 버퍼 공실율(EWVER: Exponentially Weighted Video Packet Buffer Empty Ratio, 이하 'EWVER'이라 칭함)

를 가중치

를 사용하고 수학식 5를 이용하여 계 산한다(S270).If the condition is satisfied at step S260, that is,

end

If less than or equal to, the weighted buffer vacancy rate (EWVER) is used to give greater weight to the recent buffer vacancy rate (EWVER).

Weight

And calculate using (5) (S270).

)(S280), EWVER이

보다 클 경우에는 신규 호의 수락을 거절하고(S292), EWVER이

보다 작을 경우, 즉, EWVER을 설정된 수준

이하로 유지할 수 있을 때만 신규 호를 수락한다(S290).The RAS 122 compares the EWVER obtained in step S270 with the parameters for each service type (

) (S280), EWVER

If it is larger than the rejection of accepting a new call (S292), EWVER

If less than, that is, the level at which EWVER is set

Accept the new call only when it can be maintained below (S290).

,

,

가 정의된다. 예를 들어, HTTP 서비스를 이용하는 단말기가 연결요청을 하면

와 비교한다.Parameters for each service type are set values of the call admission control method of the present invention for each service of HTTP, FTP, and Video.

,

,

Is defined. For example, if a terminal using the HTTP service makes a connection request,

Compare with

Since the call admission control method according to the preferred embodiment of the present invention described above has various types of resources occupied by each service request or call, there are two methods for accepting a new service request or call in order to classify and estimate them by traffic type. Consider the conditions. First, considering the system load, the system load does not exceed the set value even after accepting a new call. Second, make sure that new calls do not degrade the quality of the RT-VR service. To this end, the base station measures a new call only when the buffer of the terminals corresponding to the RT-VR service among the terminals currently serving can measure the empty ratio (EWVER) and maintain it below a predetermined value.

3 is a flowchart illustrating a packet scheduling method for guaranteeing a quality of service of a portable Internet service according to a preferred embodiment of the present invention.

There is a high priority and a low priority in the transmission priority, and the BE service always has a low priority. The RT-VR service basically has a low priority, but is changed to a high priority according to the video buffer state and handoff of the portable Internet terminal 110.

가

보다 작고

보다는 큰 단말, 마지막으로

가

보다 작은 단말의 세 가지 유형으로 나뉘고, 각각에 해당하는 단말의 데이터 중 우선 순위 전송 큐(PQ)에 넣을 패킷의 수가 각각 h, n, m 이다. 그리고 패킷의 크기(큐 크기)의 임계치로 사용할

,

값을 설정한다(S320).The RSA 122 defines a transmission priority queue PQ for performing packet scheduling, and sets h, n, and m values (S310). Here, the h, n, m values indicate the number of packets to be transmitted to the priority queue among the data of the terminal when priority is applied for each terminal type. Here, the types of priority are classified into three types. Firstly, a terminal that has data to be transmitted and is going to handoff, that is, has transmitted a HO_REQ (Handoff_Request Message) and has not yet received a HO_IND (Handoff_Indication Message).

end

Less than

Larger than terminal, finally

end

It is divided into three types of smaller terminals, and the number of packets to be put in the priority transmission queue (PQ) among the data of the corresponding terminal is h, n, and m, respectively. And use it as a threshold for packet size (queue size)

,

A value is set (S320).

Then, the RAS 122 calculates the size (queue size) of the remaining amount of data in the video buffer for each portable Internet terminal i using Equation 6 (S330).

은 시간 (t-1)에서 휴대인터넷 단말기 i의 큐 크기이고,

는 (t-1) 시간 동안 전송된 데이터의 량이고,

는 데이터의 재생률(속도)이다.

는 프레임의 길이이다. max{a, b}는 a와 b 중 큰 수를 선택하는 함수이다.

Is the queue size of the mobile Internet terminal i at time (t-1),

Is the amount of data transmitted in (t-1) hours,

Is the refresh rate (speed) of the data.

Is the length of the frame. max {a, b} is a function that selects the larger of a and b.

Based on the calculation result of step S330, the RAS 122 determines whether there is data to be transmitted (S340), and when there is data to be transmitted, the RAS 122 determines that all of the portable Internet terminals 110 are in the handoff state. It is determined whether there is a (S350).

가

보다 작거나 같은지 판단한다(S360). If the portable Internet terminal 110 in the handoff state exists in step S350, the corresponding RAS 122 moves the h packet of the traffic of the portable internet terminal i to the PQ (S352). If the portable Internet terminal 110 in the handoff state does not exist

end

It is determined whether it is smaller than or equal to (S360).

가

보다 작거나 같으면서

보다 큰 휴대인터넷 단말기(110)가 존재하는지 판단한다(S360).

가

보다 작거나 같으면서

보다 큰 휴대인터넷 단말기(110)가 존재한다면 RAS(122)는 해당 휴대인터넷 단말기 i의 트래픽 중 n 패킷을 PQ로 이동한다(S362).After performing step S352, the RAS 122 performs all the portable Internet terminal 110

end

Less than or equal to

It is determined whether a larger portable Internet terminal 110 exists (S360).

end

Less than or equal to

If there is a larger portable internet terminal 110, the RAS 122 moves n packets of the traffic of the portable internet terminal i to the PQ (S362).

가

보다 작거나 같은 휴대인터넷 단말기(110)가 존재하는지 판단한다(S370).

가

보다 작거나 같은 휴대인터넷 단말기(110)가 존재한다면 RAS(122)는 해당 휴대인터넷 단말기 i의 트래픽 중 m 패킷을 PQ로 이동한다(S372).After performing step S362, the RAS 122 performs all the portable Internet terminal 110

end

It is determined whether there is a smaller or equal portable Internet terminal 110 (S370).

end

If there is a smaller or equal portable Internet terminal 110, the RAS 122 moves the m packet of the traffic of the portable Internet terminal i to the PQ (S372).

After performing step S372, the RAS 122 first transmits the data in the transmission queue PQ in a frame (S380).

는 수학식 7을 이용하여 계산한다.Data to be sent to each terminal i in the corresponding frame t

Is calculated using Equation 7.

는 단말 i에게 전송되어야 할 우선 순위 데이 터를 전부 보내기 위해 필요한 RA의 수를 나타내며,

는 모든 단말의

의 합이다. 이때,

는 단말 i에게 전송할 높은 우선 순위 데이터의 양뿐만 아니라 단말 i의 채널 품질에 의해 결정된다. 즉, 채널의 품질이 좋으면 높은 MSC(Modulation and Coding Scheme)를 적용할 수 있기 때문에 같은 양의 데이터를 상대적으로 적은 RA로 보낼 수 있다.Here, RA is the minimum transmission unit that can be allocated to the terminal to determine the data to be carried in the frame,

Denotes the number of RAs needed to send all priority data to be transmitted to UE i.

Of all terminals

Sum of At this time,

Is determined by the channel quality of the terminal i as well as the amount of high priority data to send to the terminal i. In other words, if the quality of the channel is good, a high modulation and coding scheme (MSC) can be applied, so that the same amount of data can be sent with a relatively small RA.

의 크기가 프레임 RA보다 적을 경우에는 프레임의 남은 RA를 사용하여 낮은 우선 순위 데이터를 전송한다. 만약

가 프레임 RA보다 클 경우에는 전송하지 못한 데이터는 다음 프레임에서 전송하게 된다.In step S380

If the size of P is smaller than the frame RA, low priority data is transmitted using the remaining RA of the frame. if

If is larger than the frame RA, the untransmitted data is transmitted in the next frame.

If the RA remaining in the frame exists after the transmission of the PQ is completed, the low priority data is transmitted (S390).

The priority between terminals applied when the RA is allocated to each terminal in steps S380 and S390 may be differently applied according to a policy used by the system.

가

보다 크면 휴대인터넷 단말기(110) i로 전송될 모든 RT-VR 서비스의 패킷은 낮은 우선 순위가 된다.

가 정해진 임계치

이하가 되면 이 휴대인터넷 단말기(110)로 전달될 송신 큐의 맨 앞에 있는 n 개의 패킷의 우선 순위가 낮은 상태에서 높은 우선 순위로 변경된다. 또한,

가

이하인 동안은 휴대 인터넷 단말기로 전달될 송신 큐의 처음 m 패킷의 우선 순위가 높은 우선 순위로 변경된다.In other words,

end

If larger, packets of all RT-VR services to be transmitted to the portable Internet terminal 110 i have a lower priority.

Threshold

In the following case, the priority of the n packets at the beginning of the transmission queue to be delivered to the portable Internet terminal 110 is changed from the low priority to the high priority. Also,

end

During this time, the priority of the first m packets of the transmission queue to be delivered to the portable Internet terminal is changed to a high priority.

The user's portable Internet terminal 110 stores a larger amount of data than necessary for actual playback in order to service a seamless video or audio by managing a buffer in an application for RT-VR service. It can cope with delay caused by channel condition or load of application server. Therefore, when the buffer of the terminal receiving the RT-VR service is full, the base station estimates the buffer amount of the RT-VR service without transmitting the data for the RT-VT service more preferentially than the data for the BE service. That is, only a call estimated to be placed in a situation where a video or audio stream is to be cut off by the user is characterized in that the priority of the RT-VR service is higher than that of the BE service.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention pertains may make various modifications and changes without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

As described above, the present invention provides a call admission control method for classifying and estimating various resources occupied by a service request or a call by traffic type to satisfy the QoS of the RT-VR service and the BE service and to efficiently use the radio resources. By managing, the quality of service felt by the user can be improved.

In the case of a system supporting mobility, a seamless service can be received even when moving by packet scheduling considering handoff.

In addition, according to the present invention, it is possible to reduce the investment cost by increasing the efficiency of the system.

Claims (14)

A system for performing call admission control in a mobile Internet system, BE (Best) which includes Real Time-Variable Rate (RT-VR) service including video on demand (VOD) and music on demand (MOD) and file download and web browsing from a packet data server. A mobile Internet terminal equipped with a mobile Internet platform for receiving and using an Effort service and driving various applications, and having a built-in browser for connecting to the mobile Internet; A wireless access network that transmits and receives a signal wirelessly with the portable Internet terminal and performs handoff and wireless resource management functions of the portable Internet terminal; An edge router (ER) for managing a session to provide a packet data service and relaying transmission and reception of packet data between the packet data server and the wireless access network; A home agent (HA) for routing the packet data transmitted from the packet data server connected to a network including the Internet; An AAA (Authentication, Authorization, Accounting) for performing charging for the packet data used in the portable Internet terminal in connection with the ER and authenticating a connection from the portable Internet terminal; A backbone network interconnecting the ER, the HA, and the AAA, receiving the packet data from the external packet data server, and transmitting the packet data to the wireless access network; And When the portable internet terminal accesses the portable internet system and requests a multimedia service including a video service, the content server searches for a stored database and provides the packet data to the portable internet terminal. The wireless access network may include a Video Packet Buffer Empty Ratio (VER) which is a ratio of emptying buffers of the portable Internet terminals corresponding to the RT-VR service among the currently available portable Internet terminals. And a new call is accepted only when the measurement and the video packet buffer vacancy rate can be maintained below a predetermined value. delete The method of claim 1, The wireless access network is a base station of the portable Internet system, and wirelessly transmits the packet data to the portable Internet terminal, the low power RF / IF function and the controller function, the OFDMA / TDD packet scheduling and channel multiplexing function, service characteristics and propagation environment. A radio access station (RAS) having the call admission control function, a 50 Mbps fast traffic real-time control function, a handoff function, and the like; And an access control router (ACR) having a function of including a handoff control function, a packet routing function, and an internet access function between the RASs as a packet access router that connects the RASs by receiving a plurality of the RASs. Call admission control system in a mobile Internet system. The method of claim 1, The content server includes an entertainment service including movies, music, music videos, and dramas, and a database providing the multimedia service for providing various information including news, weather, maps, and trips by video and voice. Call admission control system in a mobile Internet system, characterized in that. After accepting a new call in the mobile Internet system, the system usage rate does not exceed the preset system usage rate, and the video of the mobile Internet terminals corresponding to RT-VR (Real Time-Variable Rate) service among the currently available mobile Internet terminals Call admission control to ensure the quality of service of the mobile Internet system accepting the new call when the packet packet vacancy ratio (VER) is kept below a preset VER value In the (Call Admission Control) method, (a) calculating an average of the VERs of the portable Internet terminals provided with a service in the portable internet system; (b) It is determined whether there is a request for connection of the new call, and when there is a request, the system utilization rate and the resource requirement estimate of the new call are calculated, and the system utilization rate and the estimated resource utilization rate of the system at the time of call acceptance are calculated using the resource requirement estimate of the new call. Calculating; (c) reject the acceptance of the new call if the estimated utilization of the system at the time of call acceptance is greater than the system utilization parameter by comparing the estimated utilization of the system at the time of call acceptance with a predefined system utilization parameter; Calculating an Exponentially Weighted Video Packet Buffer Empty Ratio (EWVER) if the estimated utilization rate of the system upon acceptance is less than or equal to the system utilization parameter; And (d) comparing the EWVER with a predefined VER parameter for each service type, if the EWVER is greater than the VER parameter, rejecting the acceptance of the new call, and accepting the new call if less than or equal to Call admission control method in a mobile Internet system comprising a. The method of claim 5, wherein in step (a), The total system time of the mobile Internet system is divided into time slots of a certain length, the time is represented using the slot number, and each cycle is arbitrarily defined.

And calculating the VER average of the portable Internet terminals for each frame. The method of claim 5, wherein in step (b), The system utilization rate is the number of Resource Allocation (RA) units used for transmission traffic during frame t in which a call request is made.

And the total number of RA units during the frame t

Using the ratio of

Call admission control method in a mobile Internet system, characterized in that the calculation by applying. The method of claim 5, wherein in step (b), The resource requirement estimate of the new call is the number of RA units used as transport traffic for each service area during frame t for each service type (HTTP: Hypertext Transfer Protocol, FTP: File Transfer Protocol, Video).

And the number of mobile Internet terminals that received traffic in each service area during frame t

Using the ratio of

Call admission control method in a mobile Internet system, characterized in that the calculation by applying. The method of claim 5, wherein in step (c), The system utilization parameter, which is a threshold value of the system utilization, is defined in advance, and when the system estimated usage rate at the call acceptance is less than or equal to the parameter of the system utilization compared with the estimated usage rate of the system at the call acceptance, the new A call admission control method in a mobile Internet system, characterized in that accepting a call request. The method of claim 5, wherein in step (d), And predefining the VER parameter, which is the threshold of the EWVER, and accepting the request of the new call if the EWVER is less than or equal to the VER parameter compared to the EWVER. delete delete delete delete

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