KR102161014B1 - Method and apparatus for scheduling of packet - Google Patents

Abstract

The present invention relates to a packet scheduling method and apparatus for flexibly performing Delay Based Scheduling according to a configuration ratio of a VoIP packet (Voice over Internet Protocol Packet) and a MBB packet (Mobile Broadband Packet). The packet scheduling apparatus of the present invention calculates the configuration ratio of the received VoIP packet (Voice over Internet Protocol Packet) and the MBB packet (Mobile Broadband Packet), and compares the calculated configuration ratio to allow delay due to the buffering of the VoIP packet. Changes the PDB value (Packet Delay Budget Value) representing the maximum time available, and performs the VoIP packet scheduling using the changed PDB value.

Description

Packet scheduling method and apparatus {METHOD AND APPARATUS FOR SCHEDULING OF PACKET}

The present invention relates to the LTE field, and in particular, to a packet scheduling method and apparatus for flexibly performing delay-based scheduling according to a configuration ratio of a VoIP packet (Voice over Internet Protocol Packet) and a MBB packet (Mobile Broadband Packet). About.

Recently, due to the rapid development of telecommunications, computer networks, and semiconductor technologies, various services are being provided using wireless communication networks, as well as demands of consumers are increasing day by day, and the worldwide wireless Internet service market is exploding. It is a trend. Accordingly, services provided by a mobile communication system using a wireless communication network are developing not only a voice service, but also a multimedia communication service transmitting various data. With the recent increase in smartphones and the increase in demand for data traffic, mobile communication providers are making investments in facilities and technologies in consideration of system load or impact in order to accommodate increased data traffic in various ways.

LTE (Long Term Evolution) is a network for realizing the requirements of 　high data rate, low-latency, and packet optimized radio access for an access network. It is designed to accommodate high-speed and rich media while ensuring backward compatibility for the existing 3GPP/non-3GPP access network. LTE is an All-IP-based network that excludes the existing 　circuit-switched-based communication, and 　Reinforces the quality of service (OoS) management function to provide real-time services (such as voice communication, video communication) and By providing differentiated QoS for real-time services (eg, web browsing, store and forward data transmission), the efficiency of network resources is improved. In addition, the bandwidth for wireless communication has been expanded by introducing smart antenna technology (ie, MIMO: multiple input multiple output).

Conventionally, the base station (eNode-B) uses a fixed Packet Delay Budget (PDB) value without considering the configuration ratio of VoIP packets (Voice over Internet Protocol Packet) and MBB packets (Mobile Broadband Packet) expected at a specific time. Delay Based Scheduling was performed.

In the case of VoIP packets, unlike MBB packets, there is no need to perform scheduling for each TTI (Transmit Time Interval) representing the scheduling unit of LTE, so the base station can buffer VoIP packets received for a certain period of time and then perform scheduling. , PDB value means the maximum (max.) time that can allow delay due to buffering of VoIP packets.

In the LTE system, the system administrator can set the PDB value to a fixed value. The PDB value is a parameter for setting the PDB value for QCI (QoS Class Indicator) defined for each service in order to implement differentiated enhancement of QoS (Quality of Service) in LTE, and is delayed in the transport network. Excluding time, it means the delay outside the base station. If the scheduler performing the scheduling at the base station (eNodeB) determines that the VoIP packet should be scheduled, the scheduling proceeds with the VoIP packet priority over the MBB packet. In this case, if the PDB value is set larger, the VoIP quality of the user is degraded. Conversely, if the PDB value is set to be small, the uplink and downlink throughput of the MBB packet is reduced. The number of MBB packets and the number of VoIP packets received by a base station of a commercial network fluctuate. If the delay-based scheduling is performed using a fixed PDB value without reflecting the network conditions, scaling may be inefficient.

In addition, when multiple VoIP packets are received, the delay times of each VoIP packet may be different. Conventionally, scheduling is performed by bundling all received VoIP packets without considering different delay times for each VoIP packet. In this case, there is a problem in that the delay time of a specific VoIP packet is significantly increased and the VoIP service quality is deteriorated. .

Korean Patent Application Publication No. 10-2010-0068450 (published on June 23, 2010)

The present invention provides a packet scheduling method and apparatus for flexibly performing Delay Based Scheduling according to a configuration ratio of a VoIP packet (Voice over Internet Protocol Packet) and a File Transfer Protocol Packet (MBB).

The packet scheduling method of the present invention comprises the steps of: a) calculating a configuration ratio of a received VoIP packet (Voice over Internet Protocol Packet) and a MBB packet (Mobile Broadband Packet), and b) comparing the calculated configuration ratio of the VoIP packet. And changing a packet delay budget value (PDB) indicating a maximum time to which a delay due to buffering can be allowed, and c) scheduling the VoIP packet using the changed PDB value.

In addition, the packet scheduling apparatus of the present invention uses the configuration ratio of the received VoIP packet (Voice over Internet Protocol Packet) and MBB packet (Mobile Broadband Packet) to indicate the maximum time that can allow the delay due to buffering of the VoIP packet. And a processor that changes a packet delay budget value (PDB) and performs scheduling of the VoIP packet by using the changed PDB value, and a storage unit that stores the PDB value.

According to the present invention, mobile communication service quality is performed by flexible scheduling in consideration of the composition ratio of the received VoIP packet (Voice over Internet Protocol Packet) and the MBB packet (Mobile Broadband Packet) and the delay time of the received VoIP packet. Can improve.

1 is a diagram showing the configuration of a mobile communication network according to an embodiment of the present invention.
2 is an exemplary diagram showing the configuration of an EPC network according to an embodiment of the present invention.
3 is an exemplary view showing the configuration of a packet scheduling apparatus according to an embodiment of the present invention.
4 is a flow chart showing a procedure of a packet scheduling method according to an embodiment of the present invention.
5 is a flow chart showing a procedure of a packet scheduling method according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, in the following description, when there is a possibility that the subject matter of the present invention may be unnecessarily obscure, detailed descriptions of widely known functions or configurations will be omitted.

In one embodiment, the mobile communication network is, for example, a 2G wireless communication network such as Global System for Mobile communication (GSM), Code Divisoin Multiple Access (CDMA), a Long Term Evolution Network (LTE), a wireless Internet such as WiFi, and WiBro ( Mobile Internet networks such as Wireless Broadband Internet) and WiMax (World Interoperability for Microwave Access) or mobile communication networks supporting packet transmission (e.g., 3G mobile communication networks such as WCDMA or CDMA2000, High Speed Downlink Packet Access (HSDPA) or High Speed Downlink Packet Access (HSUPA)) 3.5G mobile communication network such as Speed Uplink Packet Access), or 4G mobile communication network currently in service), macro base station (macro eNodeB), micro base station (Pico eNodeB, Home-eNodeB), and user equipment (UE: User Equipment) Any other mobile communication network included as an element may be included, but is not limited thereto. Hereinafter, the LTE radio access network E-UTRAN (Evolved Universal Terrestrial Radio Access Network) will be mainly described.

As shown in FIG. 1, a mobile communication network may be composed of one or more network cells, and includes a HetNet (Heterogeneous Network) environment in which different types of network cells may be mixed in the mobile communication network. The mobile communication network is a micro base station (Pico eNodeB, Home-eNodeB, relay, etc.) that manages small network cells (e.g.,'small cells' such as pico cells and femtocells) (11~15, 21~23, 31~33), macro eNodeB (10, 20, 30) that manages a wide range of cells (e.g.,'macro cell'), user terminal 40, SON (Self Organizing & Optimizing) Networks) Server (50), Mobility Management Entity (MME) (60), Serving Gateway (S-GW) (80), Packet Data Network (PDN) Gateway (P-GW) (90), and Home Subscriber Server (HSS) It may include (100). Each component shown in FIG. 1 is exemplary, and each component of a mobile communication network in which the present invention can be implemented is not limited to that shown in the drawing.

The macro base station (10, 20, 30) is, for example, a cell having a radius of about 1 km, which can be used in an LTE network, a WiFi network, a WiBro network, a WiMax network, a WCDMA network, a CDMA network, a UMTS network, a GSM network, etc. It may include the features of the macro cell base station that manages, but is not limited thereto.

Micro base stations (11-15, 21-23, 31-33) can be used in, for example, LTE network, WiFi network, WiBro network, WiMax network, WCDMA network, CDMA network, UMTS network, GSM network, etc. It may include features of a pico base station, an indoor base station or a femto base station, and a relay that manages cells having a radius of m to several tens of m, but is not limited thereto.

Subminiature base stations (11~15, 21~23, 31~33) and macro base stations (10, 20, 30) each have their own SON server (50), MME (60), S-GW (80), P-GW (90), the HSS (100) may have connectivity with a core network.

The user terminal 40 is a mobile network used in a 2G wireless communication network such as a GSM network and a CDMA network, a wireless Internet network such as an LTE network and a WiFi network, a mobile Internet network such as a WiBro network and a WiMax network, or a mobile communication network supporting packet transmission. The characteristics of the terminal may be included, but the present invention is not limited thereto.

The management server (O&M server) 70, which is a network management device of a micro base station, is in charge of configuration information and management of micro base stations (11 to 15, 21 to 23, 31 to 33) and macro base stations (10, 20, 30). . The management server 70 may perform all of the functions of the SON server 50, the MME 60, and the HSS 100. The SON server 50 may include an arbitrary server that performs macro/micro base station installation and optimization and provides basic parameters or data required for each base station. The MME 60 may include any entity used to manage the mobility of the user terminal 40 or the like. In addition, MME (60) performs the function of a base station controller (BSC: Base Station Controller), resource allocation, call control, handover control for the base station (pico eNodeB, Home-eNodeB, macro eNodeB, etc.) connected to itself, Voice and packet processing control, etc. can be performed. The HSS 100 is a kind of database for service/authentication of subscribers.

In one embodiment, one management server 70 can perform all of the functions of the SON server 50, the MME 60, and the HSS 100, and the SON server 50, the MME 60, and the HSS 100 can manage one or more macro base stations 10, 20, 30 and one or more micro base stations 11 to 15, 21 to 23, and 31 to 33.

In the mobile communication network, a network cell in which a macro cell, a pico cell, and a femto cell are mixed is assumed, but the network cell can be configured with only a macro cell-pico cell and a macro cell-femto cell.

Specifically, micro base stations (11~15, 21~23, 31~33) can broadcast the system information SIB (System Information Block) to the femtocell area they manage, and the SIB has access to the femtocell. Includes a CSG indicator (Closed Subscriber Group indicator) indicating whether or not it is restricted. SIB is a message in which a base station (HeNB, macro eNB) broadcasts information on its own cell to all user terminals 40, and is a CGI (Cell Global Identity) (the only cell identification factor in the network), CSG indication (micro eNB). A factor indicating that it is a base station), CSG ID (ID for a specific subscriber group), etc. may be included.

When the mobile communication network is assumed to be an LTE network, the LTE network is linked to an inter-RAT network (WiFi network, WiBro network, WiMax network, WCDMA network, CDMA network, UMTS network, GSM network, etc.). When one of the inter-RAT networks (eg, WiBro network) is the mobile communication network, it is also linked to other networks (LTE network, WiFi network, WiMax network, WCDMA network, CDMA network, UMTS network, GSM network, etc.). In the drawing, one network (e.g., LTE network) and other networks (WiFi network, WiBro network, WiMax network, WCDMA network, CDMA network, UMTS network, GSM network, etc.) are shown separately, but one network and the other network are overlaid. (overlay) is assumed.

When subminiature base stations (11 to 15, 21 to 23, 31 to 33) or/and macro base stations (10, 20, 30) are collectively referred to as'base station device', the base station device of LTE (eNB in FIG. 2) ( 25-n), E-UTRAN (Evolved UMTS Terrestrial Radio Access Network) has an IP-based flat structure and processes data traffic between the user terminal 40 and the core network. The signal control between them is in charge of the MME (60). The MME 60 is responsible for signal control between the eNB 25-n and the S-GW 80, and determines where to route data incoming from the user terminal 40. The S-GW (80) is in charge of an anchor function for the movement of user terminals between the eNBs (25-n) and between the 3GPP network and the E-UTRAN, and to the IP network 110 through the P-GW (90). Connect. The core network equipment MME (60)/S-GW (80) manages a number of eNBs (25-n), and each eNB (25-n) is composed of several cells. The S1 interface ("S1-MME" and "S1-U" in FIG. 2) is used between the eNB (25-n) and the MME (60)/S-GW (80), and the hand between the eNBs 25-n X2 interface (not shown) is used for over and SON functions.

The network interface is set up by setting an S1 interface that connects with the MME 60 at the center of the system and an X2 interface, which is a network line for direct communication with the eNBs 25-n of other cells present in the current system. The S1 interface exchanges signals with the MME 60 to exchange OAM (Operation and Management) information for supporting the movement of the user terminal 40. In addition, the X2 interface serves to exchange signals for fast handover, load indicator information, and information for self-optimization between the eNBs 25-n.

2 is an exemplary diagram showing the configuration of an EPC network according to an embodiment of the present invention.

E-UTRAN (25) is an LTE radio access network consisting of eNBs (25-1,...25-n,...), IP-based, and between the UE (40) and the wireless communication core network (Core Network). It is located in and carries data and control information. In addition, when a terminal using the LTE system uses a voice service, a paging request for the purpose of a circuit switch (CS) fallback and an SMS message to be provided with a voice service by moving to an existing 2G/3G mobile communication network are sent to the UE 40. ) And direct connection to a target cell where CS service is available.

In FIG. 2, "LTE-Uu" represents a radio interface between the E-UTRAN 25 and the UE 40, and "S1-MME" represents an interface between the MME 60 and the E-UTRAN 25, "S1-U" represents the interface between the S-GW (80) and E-UTRAN (25), "S11" represents the interface between the S-GW (80) and the MME (60), and "S5/S8" "" represents the interface between the P-GW (90) and the S-GW (80), "SGi" may represent the interface between the IP network 110 and the P-GW (90). And "S6a" may represent an interface between the HSS (100) and the MME (60).

The UE 40 and the eNB (25-1,...25-n,...) of the E-UTRAN (25) communicate through the Radio Resource Control (RRC) protocol, and the eNB (25-n) The broadcasting message to the controlled cell area is defined as an RRC message. The RRC message may include control messages descending from the NAS (Non-Access Stratum) protocol, and the control messages are not read in the E-UTRAN 25 and are transparently transmitted to the UE 40 or the core network. .

The eNB (25-n) is an endpoint for the radio signal of the E-UTRAN (25), the control signal is interlocked with the MME (60) through the S1-MME interface, and the data traffic is S-GW through the S1-U interface. It is linked with (80). The S-GW 80 performs an anchor for mobility in the E-UTRAN 25 and a buffering function for downlink traffic. The P-GW 90 is a connection point of the external IP network 110 and performs IP allocation and billing for mobile subscribers and traffic control functions for user data.

The IP network 110 provides an IP Multimedia Subsystem (IMS) service to the UE 40 in the EPC network, and provides a Policy & Charging Rule Function (PCRF), IMS nodes (for example, Proxy Call Session Control Function (P-CSCF)). ), I-CSCF (Interrogating Call Session Control Function), S-CSCF (Serving Call Session Control Function), AF (Application Function)), and the like.

The UE 40 exchanges call control messages for multimedia services with IMS nodes through the EPC bearer (provided by E-UTRAN/S-GW/P-GW) using the Gm Interface.

The E-UTRAN 25 provides a radio communication function to the UE 40 and performs a function of managing radio resources for this purpose.

The MME 60 may perform authentication of the UE 40 by receiving authentication information for authenticating the UE 40 from the HSS 100. In addition, the MME (60) manages the mobility of the UE (40) and the eNB (25-n) from the top of the eNB (25-n), and the establishment / release of the EPS (Evolved Packet System) session and bearer (Bearer) The same call control function can be performed. The UE 40 and inter-network mobility and session control are handled by the NAS protocol at the NAS (Non-Access Stratum) layer located in the control plane of the UE 40 and the MME 60, and the UE 40 And MME 60 communicate with each other through NAS messages. NAS functions are largely divided into EMM (EPS Mobility Management) and ESM (EPS Session Management) functions. In addition, the MME 60 may be directly connected to the IP network 110 through the S-GW 80 and the P-GW 90. The call processing control signal of the eNB (25-n) is transmitted to the S-GW (80) through the MME (60), and a message for requesting work required for call processing is transmitted to the P-GW (90) according to the call processing control signal. Can be transferred to. The EMM is a sub-layer located in the NAS layer. As the EMM procedure is performed, the UE 40 has 7 EMM states and the MME 60 has 4 EMM states. In order for the UE 40 and the MME 60 to exchange NAS messages, a signaling connection through which NAS messages can be transmitted between the UE 40 and the MME 60 must be created, which is called an EPS Connection Management (ECM) connection. . The ECM connection is a logical connection and is actually composed of an RRC connection established between the UE 40 and the eNB 25-n and an S1 signaling connection established between the eNB 25-n and the MME 60. That is, when the ECM connection is established/released, it means that both the RRC connection and the S1 signaling connection have been established/released. When the ECM connection is established, the RRC connection is established when viewed from the UE 40, and the S1 signaling connection is established when viewed from the MME 60. The ECM connection has a NAS signaling connection, that is, ECM-Connected (connection establishment) and ECM-Idle (connection release) status depending on whether or not ECM connection is established. According to the EMM procedure, the ECM-Connected state and the ECM-Idle state are frequently moved. This change process is called a state transition.

The S-GW 80 serves as a gateway between the 3GPP network and the E-UTRAN 25, and the handover between the eNBs 25-n and the mobility of the UE 40 between the 3GPP network-3GPP networks (inter-3GPP) A mobility anchor function for provision may be performed. The S-GW 80 may transmit a task required for call processing to the P-GW 90 according to a control signal from the eNB 25-n.

The P-GW 90 may allocate an IP address to the UE 40 and apply different QoS policies for each UE 40. In addition, the P-GW 90 serves as a gateway to a packet data network (PDN) so that the UE 40 can access the Internet or a data network such as the Internet to receive a service.

As an embodiment, the S-GW 80 and the P-GW 90 are separated and shown to communicate with the S5/S8 interface, but the S-GW 80 and the P-GW 90 are connected to one gateway ( It can be implemented as a single gateway).

The HSS 100 may manage authentication information for authenticating the UE 40, location information of the UE 40, and a profile of the UE 40. The profile of the UE 40 may include QoS class information (eg, priority, maximum usable bandwidth, etc.) suitable for a service product to which each UE 40 subscribes. As an embodiment, authentication information for authenticating the UE 40 and a profile of the UE 40 may be transmitted from the HSS 100 to the MME 60 when the UE 40 accesses the network.

PCRF (not shown) manages the rules for policy and charging, and the P-GW 90 and S-GW 80 provide and use appropriate QoS to the UE 40. It allows you to perform the charging function for the bearer.

The IMS node (not shown) is composed of nodes such as P-CSCF, I-CSCF, S-CSCF, AF in detail, and the UE 40 provides multimedia services such as VoIP (Voice over IP) and video calls. give.

3 is an exemplary diagram showing the configuration of a packet scheduling apparatus according to an embodiment of the present invention.

3, the packet scheduling apparatus 300 may include a storage unit 310, a processor 320, a transmission/reception unit 330, and a system bus 340. As an embodiment, the storage unit 310, the processor 320, and the transmission/reception unit 330 may be connected to each other using the system bus 340. As an embodiment, the packet scheduling apparatus 300 may be included in the macro base station 10, 20, 30 or the micro base station 11 to 15, 21 to 23, 31 to 33, and the macro base station 10, 20, 30) Or may be provided separately from the micro base station (11 ~ 15, 21 ~ 23, 31 ~ 33). As an embodiment, the packet scheduling device 300 may flexibly set a PDB value (Packet Delay Budget Value) in various ways, and the PDB value may indicate the maximum time to allow a delay due to buffering of a VoIP packet. have.

The storage unit 310 may store information on a minimum PDB value, a maximum PDB value, and a packet delay threshold. As an embodiment, the storage unit 310 receives and stores the minimum PDB value and the maximum PDB value from the administrator of the macro base station (10, 20, 30) or the micro base station (11 to 15, 21 to 23, 31 to 33). I can. For example, the minimum PDB value may have a value of 0 msec., the maximum PDB value may be set to a value of 1000 msec., and the VoIP packet delay threshold is 500 msec. It can be set to have a value of ~ 1000 msec. The storage unit 130 is a ROM (Read Only Memory), RAM (Random Access Memory), CD (Compact Disc)-ROM, Magnetic Tape, Floppy Disk, Optical Data storage device Alternatively, the implementation may include a carrier wave (for example, transmission through the Internet), but is not limited to such implementation.

The processor 320 calculates or predicts the composition ratio of a VoIP packet for a voice call using a mobile communication network and a Mobile Broadband Packet for wireless Internet access using a mobile communication network in addition to a voice call. You can change the PDB value. In other words, if the rate of VoIP packets is expected to be higher or higher than the rate of MBB packets, the PDB value can be reduced by a preset value, and when the rate of VoIP packets is lower than or equal to the rate of MBB packets, or lower or equal If expected, the PDB value can be increased by a preset value. In addition, the processor 320 may set the PDB value as the maximum PDB value when the number of VoIP packets is 0, and set the PDB value as the minimum PDB value when the number of VoIP packets is not 0 and the number of MBB packets is 0. I can. The administrator can set an offset in advance to change the weight for the VoIP packet or MBB packet. If you want to give VoIP more weight, you can set the offset as a negative number and reflect it in the calculated ratio of MBB packets. If you want to weight the MBB packets, set the offset as positive and reflect it in the calculated ratio of MBB packets. have. As an embodiment, the processor 320 uses a trend or queuing theory in which the composition ratio of VoIP packets and MBB packets has changed in the past (Queuing Theory) Thus, the composition ratio of VoIP packets and MBB packets can be estimated. For example, the ratio of VoIP packets and MBB packets (+ offset) was 20:80 before 100 TTI (Transmit Time Interval: LTE scheduling unit) from the current point of time, and before 200 TTI, VoIP packets and MBB Assuming that the ratio of packets (+ offset) was 30:70, and the ratio of VoIP packets and MBB packets (+ offset) before 300 TTI was 40:60, the ratio of VoIP packets and MBB packets has changed in the past. If considered, the ratio between VoIP packets and MBB packets (+ offset) at the current time can be predicted to be 10:90. That is, the processor 320 calculates a change in the composition ratio of the VoIP packet and the MBB packet for a predetermined time, and when the composition ratio of the VoIP packet increases compared to the MBB packet for a predetermined time, the PDB value can be increased. If the composition ratio of the VoIP packet is decreased compared to the MBB packet, the PDB value can be decreased. In addition, the processor 320 sets the PDB value to a preset value when the delay of the VoIP packet is expected to be greater than or greater than the packet delay threshold (eg, 500 msec. ~ 1000 msec.) in consideration of the delay of the VoIP packet. When the delay of the VoIP packet is less than or equal to the packet delay threshold or is expected to be less than or equal to the packet delay threshold, the delay of the VoIP packet after a predetermined time (for example, 20 msec. ~ 50 msec.) elapses. Can be compared again with the packet delay threshold. In addition, the processor 320 does not calculate the configuration ratio of the VoIP packet and the MBB packet when either the VoIP packet or the MBB packet is not received by the transceiver 330, and compares the delay of the VoIP packet and the packet delay threshold. It can also be set not to perform. In addition, the processor 320 may perform packet scheduling of the VoIP packet and the MBB packet by using the set PDB value.

The transceiver 330 can transmit/receive a VoIP packet and an MBB packet with a user terminal (see reference numeral 40 in FIG. 1), and also MME (see reference numeral 60 in FIG. 1) or S-GW (see reference numeral in FIG. 1). 80) and VoIP packets and MBB packets.

4 is a flow chart showing a procedure of a packet scheduling method according to an embodiment of the present invention.

As shown in FIG. 4, the packet scheduling apparatus 300 may calculate or predict a configuration ratio of a received VoIP packet and an MBB packet (S410). The packet scheduling apparatus 300 may check whether the number of VoIP packets is 0 by using the calculated or predicted configuration ratio, and if it is 0, set the PDB value as the maximum PDB value. In addition, when the number of VoIP packets is not 0, the packet scheduling apparatus 300 may check whether the number of MBB packets is 0, and when the number of VoIP packets is 0, set the PDB value as the minimum PDB value. In addition, when the number of MBB packets is not 0, the packet scheduling apparatus 300 compares the composition ratio of the calculated or predicted VoIP packet and MBB packet (S420), and the calculated VoIP packet is greater than the MBB packet (+ offset). The PDB value may be decreased by a predetermined value (S430), and when the VoIP packet is less than or equal to the MBB packet (+ offset), the PDB value may be increased by a predetermined value (S440). Thereafter, the packet scheduling apparatus 300 may perform scheduling of a VoIP packet using the set PDB value (S450).

5 is a flow chart showing a procedure of a packet scheduling method according to an embodiment of the present invention.

As shown in FIG. 5, the packet scheduling apparatus 300 may calculate a delay time of a received VoIP packet. As an embodiment, the packet scheduling apparatus 300 may calculate or predict a delay time using information on a time stamp included in a received VoIP packet or information on a transaction identification (ID). (S510). The packet scheduling apparatus 300 checks whether the delay time of the VoIP packet is greater than the packet delay threshold value using the calculated or predicted delay time of the VoIP packet (S520), and the delay time of the VoIP packet is less than the packet delay threshold value. In the same case, the procedures of S510 and S520 may be performed again after a predetermined time elapses. Meanwhile, when the calculated or predicted delay time of the VoIP packet is greater than the packet delay threshold value, the packet scheduling apparatus 300 may decrease the PDB value by a predetermined value (S530). Thereafter, the packet scheduling apparatus 300 may perform scheduling of a VoIP packet using the set PDB value (S540).

Although the method has been described through specific embodiments, the method can also be implemented as computer-readable code on a computer-readable recording medium. The computer-readable recording medium includes all types of recording devices that store data that can be read by a computer system. Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage, etc., and also implemented in the form of a carrier wave (for example, transmission through the Internet). Include. In addition, the computer-readable recording medium is distributed over a computer system connected through a network, so that computer-readable codes can be stored and executed in a distributed manner. In addition, functional programs, codes, and code segments for implementing the above embodiments can be easily inferred by programmers in the technical field to which the present invention belongs.

In the present specification, the present invention has been described in connection with some embodiments, but it should be understood that various modifications and changes can be made without departing from the spirit and scope of the present invention that can be understood by those skilled in the art to which the present invention belongs. something to do. In addition, such modifications and changes should be considered to fall within the scope of the claims appended to this specification.

11~15,21~23,31~33: micro base station 10,20,30: macro base station
40: user terminal 50: SON server
60: MME 80: S-GW
90: P-GW 100: HSS
300: packet scheduling device 310: storage
320: processor 330: transceiver
340: system bus

Claims (12)

As a packet scheduling method,
a) calculating the composition ratio of the received VoIP packet (Voice over Internet Protocol Packet) and MBB packet (Mobile Broadband Packet) by the processor,
b) changing, by the processor, a packet delay budget value (PDB) indicating a maximum time that a delay due to buffering of the VoIP packet can be allowed by comparing the calculated configuration ratio; and
c) performing, by the processor, scheduling the VoIP packet using the changed PDB value,
Step b),
By the processor, when the number of VoIP packets is greater than the number of MBB packets, the PDB value is reduced by a predetermined value, and when the number of VoIP packets is less than or equal to the number of MBB packets, the PDB value is determined. And increasing by a value. delete The method of claim 1,
Step b),
And setting, by the processor, a maximum PDB value and a minimum PDB value,
The maximum PDB value is when the number of VoIP packets is 0, and the minimum PDB value is when the number of VoIP packets is not 0 and the number of MBB packets is 0. The method of claim 1,
Step c),
Setting, by the processor, an offset for different weights for the VoIP packet or the MBB packet; and
And comparing, by the processor, a configuration ratio of the VoIP packet and the MBB packet in consideration of the offset. The method of claim 1,
After step b) and before step c),
Calculating, by the processor, a delay time of the VoIP packet,
And reducing, by the processor, the PDB value by a predetermined value when the delay time of the VoIP packet is greater than a packet delay threshold. The method of claim 1,
Step a),
Calculating, by the processor, a change in the composition ratio of the VoIP packet and the MBB packet for a predetermined time; and
By the processor, when the configuration ratio of the VoIP packet increases compared to the MBB packet during the predetermined time, the PDB value is increased, and when the configuration ratio of the VoIP packet decreases compared to the MBB packet during the predetermined time, the PDB And decreasing the value. As a packet scheduling device,
Using the composition ratio of the received VoIP packet (Voice over Internet Protocol Packet) and MBB packet (Mobile Broadband Packet), the PDB value (Packet Delay Budget Value) indicating the maximum time to allow the delay due to buffering of the VoIP packet A processor that changes and performs scheduling of the VoIP packet by using the changed PDB value,
Including a storage unit for storing the PDB value,
The processor,
When the number of VoIP packets is greater than the number of MBB packets by comparing the configuration ratio of the VoIP packet and MBB packet, the PDB value is reduced by a predetermined value, and the number of VoIP packets is less than or equal to the number of MBB packets. In case, the PDB value is increased by a predetermined value. delete The method of claim 7,
The processor,
Set the maximum PDB value and the minimum PDB value,
The maximum PDB value is when the number of VoIP packets is 0, and the minimum PDB value is when the number of VoIP packets is not 0 and the number of MBB packets is 0,
The storage unit stores the maximum PDB value and the minimum PDB value. The method of claim 7,
The processor,
A packet scheduling apparatus that sets an offset for different weights for the VoIP packet or the MBB packet, and compares the configuration ratio of the VoIP packet and the MBB packet in consideration of the offset. The method of claim 7,
The processor,
A packet scheduling apparatus for calculating a delay time of the VoIP packet and decreasing the PDB value by a predetermined value when the delay time of the VoIP packet is greater than a packet delay threshold. The method of claim 7,
The processor,
Calculate a change in the composition ratio of the VoIP packet and the MBB packet for a predetermined time, increase the PDB value when the composition ratio of the VoIP packet increases compared to the MBB packet during the predetermined time, and increase the VoIP packet for the predetermined time. When the configuration ratio of is decreased compared to the MBB packet, the PDB value is decreased.

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