WO2014083960A1

WO2014083960A1 - Packet transfer control device and communications system

Info

Publication number: WO2014083960A1
Application number: PCT/JP2013/078396
Authority: WO
Inventors: 一範小澤
Original assignee: 日本電気株式会社
Priority date: 2012-11-29
Filing date: 2013-10-11
Publication date: 2014-06-05

Abstract

A packet transfer control device that, in order to avoid deterioration in Quality of Experience (QoE), connects a terminal via a network and transfers packets storing media data, using a request from the terminal, comprises: a congestion detection unit that detects network congestion; and a transfer control unit that, if the congestion detection unit has detected network congestion, sends in the upstream direction a notification requesting content having an appropriate rate or a notification requesting content having an appropriate file size, on the basis of at least either user profile information or Quality of Service (QoS) information, and also controls the transfer of packets on the basis of the QoS information.

Description

Packet transfer control device and communication system

The present invention relates to a packet transfer control device that performs packet transfer while controlling communication quality for each packet, and a communication system including the same.

In recent years, the capacity and speed of mobile networks have been increased, and systems such as LTE (Long Term Evolution) and EPC (Evolved Packet Core) have begun to be introduced.
In conventional communication systems, circuit switching for voice calls and videophone calls and packet switching for sending data are configured as separate systems. In contrast, in the LTE / EPC system, voice call data, videophone data, content distribution data, and so-called data signals (application data, document data, photo data, etc.) are sent together on the same packet communication path. It is characterized by. Furthermore, as mobile terminals, the spread of so-called smart devices such as smartphones and tablets as well as conventional so-called Galapagos mobiles is accelerating.
Thereby, in the LTE / EPC system, a packet with a huge amount of data that cannot be compared with the conventional communication system flows through the packet communication path.
Therefore, in the LTE / EPC system, it is necessary to perform packet transfer rate control. For example, Japanese Patent Laying-Open No. 2004-320452 (Patent Document 1) discloses a packet transfer control device that performs packet transfer rate control.
The packet transfer control device disclosed in Patent Document 1 includes a line congestion state determination unit, a transfer rate control determination unit, and a packet processing unit. The line congestion state determination unit determines whether the backbone line is congested based on the accumulated packet total amount that is the accumulated value of the packet size for a plurality of packets. When determining that the backbone line is in a congested state, the transfer rate control determination unit selects one or more IP (Internet Protocol) flows having a hop count value lower than the threshold value. The packet processing unit determines whether the IP flow selected by the transfer rate control determination unit is a TCP (Transmission Control Protocol) packet. In the case of a TCP packet, the packet processing unit performs the following three types of packet processing. Apply.
Specifically, 1) In the case of an outgoing packet from the server, the CE (Consultation Experience) bit of ECN (Explicit Connection Notification) is set in the TCP header. 2) In the case of a reply packet returned from the client, the advertisement window size of the TCP header is reduced and changed. 3) In the case of an acknowledgment (Ack) packet, the transmission timing of the packet to the backbone line is delayed. If it is not a TCP packet, the packet is discarded.

JP 2004-320452 A ([0051] to [0057])

Until now, packet transfer control devices (for example, EPC P-GW: Packet data network Gateway and S-GW: Serving Gateway), QCI (Quality Class Identifier Bit), MBR (Maximum Bit RateRit, GitRiteGitRite, Git ) And the like are set to control QoS (Quality of Service) for each packet.
However, since the network bandwidth of the entire LTE / EPC system varies with time depending on the temporal variation of the traffic volume, the network may be congested due to traffic concentration or the like.
Therefore, conventionally, by using a statistical method, the day of the week and the time zone in which the network is congested is examined, and the QoS parameter setting for a specific packet is changed when the day of the week or time zone information is applicable ( In particular, attempts have been made to avoid congestion by lowering the priority of QCI or narrowing down MBR and GBR.
However, such control cannot handle cases where traffic changes significantly or increases compared to statistical values due to sudden events, popular content postings, or new use by heavy users. There was a problem. As a result, there has been a problem relating to quality of experience (QoE) degradation, such as, for example, a very long content download time, or, in the worst case, the screen freezes on the terminal or the sound is interrupted.
Further, in the future, when the network is congested in a situation where it is started as a real-time communication service such as high-quality VoIP (Voice Over IP) or high-resolution videophone using the packet communication path of the LTE / EPC system, the worst case is VoIP. There is a risk of problems relating to deterioration of QoE on the terminal side, such as sound being interrupted at the terminal during a voice call, or video being disturbed or frozen at the terminal during a videophone call.
The packet transfer control device disclosed in Patent Document 1 merely discloses a technical idea of selecting one or more IP flows having a hop count value lower than a threshold value when the backbone line is congested. . That is, Patent Document 1 does not recognize the above-described problem relating to the deterioration of QoE.
An object of the present invention is to provide a packet transfer control device capable of avoiding QoE degradation.

One aspect of the present invention is a packet transfer control device for connecting a terminal via a network and transferring a packet storing media data in response to a request from the terminal, the congestion detecting unit detecting congestion of the network, And when the congestion detection unit detects congestion of the network, based on at least one of the user profile information and the QoS information, a notification requesting an appropriate rate of content is sent in the upstream direction, and the QoS information And a transfer control unit that controls packet transfer based on
Another embodiment of the present invention is a packet transfer control device for connecting a terminal via a network and transferring a packet storing media data in response to a request from the terminal, the congestion detecting unit detecting congestion of the network And when the congestion detection unit detects congestion of the network, based on at least one of the user profile information and the QoS information, a notification requesting content of an appropriate file size is sent in the upstream direction, and And a transfer control unit that controls packet transfer based on QoS information.

According to the present invention, it is possible to avoid a congestion state even when the traffic changes significantly compared to the statistical value.

FIG. 1 is a block diagram showing a connection configuration of a communication system according to the first embodiment of the present invention.
FIG. 2 is a block diagram showing a configuration of a packet transfer control device used in the communication system shown in FIG.
FIG. 3 is a block diagram showing a configuration of a rate control unit used in the packet transfer control device shown in FIG.
FIG. 4 is a block diagram showing a connection configuration of a communication system according to the second embodiment of the present invention.
FIG. 5 is a block diagram showing a configuration of a packet transfer control device used in the communication system shown in FIG.
FIG. 6 is a block diagram showing a configuration of a mobile terminal used in the communication system shown in FIG.

Hereinafter, embodiments and operations of the present invention will be described in detail with reference to the drawings.
[First Embodiment]
FIG. 1 is a block diagram showing a configuration of a communication system according to the first embodiment of the present invention. Here, a configuration in which the mobile LTE / EPC packet network 150 is used as the network is shown.
Further, in the communication system of FIG. 1, a packet transfer control device 190 (to be described later) shows a configuration using P-GW (Packet data network Gateway) or S-GW (Serving Gateway) or both. The mobile terminal is assumed to be a so-called Galapagos mobile phone, a smartphone, or a tablet.
In the communication system of FIG. 1, an example is shown in which user A and user B communicate within the same outdoor LTE radio base station apparatus (eNodeB apparatus) 194. Here, for the sake of simplicity, the number of users is two, but it goes without saying that the same configuration can be used for both one and three or more users.
In the communication system of FIG. 1, a user A uses a first mobile terminal 170 </ b> _ <b> 1 through a mobile network 150 and an IMS (IP Multimedia Subsystem) network 130 via a counterpart network (not shown). VoIP voice communication with a terminal (not shown). In addition, a configuration in which the user B downloads Web content from the Web server using the second portable terminal 170_2 during the same time period is illustrated. A TV phone may be used in place of the voice communication (voice call), but in FIG.
As an example of congestion detection, FIG. 1 shows a configuration for detecting congestion by receiving congestion information by ECN (Explicit Congestion Notification) for an upstream packet sent from a terminal. Here, when the eNodeB device 194 detects a congestion state in the wireless network, the eNodeB device 194 sets a predetermined value in the ECN field of the IP (internet protocol) header of the downlink packet from the eNodeB device to the mobile terminal, and Send to terminal. When the mobile terminal detects that the CE (Congestion Experience) bit is set in the ECN field of the IP header part in the packet received from the eNodeB, the ECN of the IP header part of the upstream packet from the mobile terminal to the packet transfer control device It is assumed that the packet transfer control device is notified of the congestion state by setting the CE bit in the field.
In the communication system of FIG. 1, when the first mobile terminal 170_1 sends out the IP address and RTP (real-time transport protocol) port number of the partner terminal from the first mobile terminal 170_1 as a connection request signal for a voice call. The connection request signal is transmitted via the eNodeB device 194 and the packet transfer control device 190 to the SIP (Session Initiation Protocol) server 110 disposed in the IMS (IP Multimedia Subsystem) network 130 and the PCRF (Policy and Charging Rules Function). ) Is transferred to at least one of the devices 191. Further, the first mobile terminal 170_1 adds at least one parameter of parameters such as voice call traffic, desired QoS class, MBR (Maximum Bit Rate), GBR (Guaranteed Bit Rate) to the connection request signal, The connection request signal to which the parameter is added can be notified to at least one of the SIP server 110 and the PCRF device 191 via the packet transfer control device 190.
The SIP server 110 receives a connection request signal for a voice call and sends a connection request signal to a partner terminal (not shown) via a partner network (not shown). When the SIP server 110 receives the Ack signal from the counterpart terminal, the SIP server 110 transmits the Ack signal to the first portable terminal 170_1 via the packet transfer control device 190 and the eNodeB device 194. When the first portable terminal 170_1 receives this, control signals for voice call are exchanged. Here, from the destination terminal, not only the IP address and RTP port number of the first portable terminal 170_1 but also the parameters of voice call traffic, desired QoS class, MBR (Maximum Bit Rate), GBR (Guaranteed Bit Rate) At least one can be added and sent out. These parameters can be transmitted not only to the SIP server 110 but also to the PCRF device 191.
The PCRF device 191 inputs the voice call traffic, the IP address of the first portable terminal 170_1, and the port number from the packet transfer control device 190 for at least one of the upstream and downstream directions. If necessary, the PCRF device 191 also inputs parameters such as a desired QoS class, MBR (Maximum Bit Rate), GBR (Guaranteed Bit Rate), etc. from the packet transfer control device 190 as QoS information. Furthermore, the PCRF device 191 identifies a user from the IP address of the mobile terminal, and reads user profile information from the user database owned by the PCRF device 191. Here, the user profile information includes, for example, user contract information. Here, the user contract information includes, as an example, a signal indicating whether the member is a premium member or a standard member, a signal indicating whether or not QoS can be downgraded during network congestion, the model name of the terminal used, and the terminal screen Information such as resolution is used. However, other information such as the upper limit value of the packet data amount, terminal capability information, and the like can be used as the user contract information.
Next, the PCRF device 191 generates a QoS parameter for QoS control based on the user profile information and the QoS information. The QoS parameter for QoS control is at least one of QCI (Quality Class Identifier) which is a value for identifying a QoS class, ARP (Allocation and Retention Priority) indicating the priority of resource reservation and retention, MBR, and GBR. is there. Here, the MBR and the GBR are used as they are when received from the packet transfer control device 190, and are generated by the PCRF device 191 when there is no reception.
The PCRF device 191 generates at least one of these four types of QoS parameters for each of the uplink direction and the downlink direction, and sends the generated parameter to the packet transfer control device 190. For the first mobile terminal 170_1, the user profile is “Premier Member”, “QoS is not allowed to be downgraded during network congestion”, and the traffic is a voice call. Specifically, for example, QCI = 1 (Conversational Voice), ARP = 2, GBR = 12.2 kbps, and MBR = 22.8 kbps are set for both uplink and downlink. Here, as an example, assuming that an AMR-NB (Adaptive Multi-Rate Narrowband) audio codec is used in a mobile terminal, the above parameter values are used. As another configuration, an AMR-WB (Adaptive Multi-Rate Wideband) audio codec can be used. In this case, the value of GBR can be changed.
Next, the second portable terminal 170_2 designates the URL (uniform resource locator) of the Web server 145 and sends a connection request signal. When the connection request signal is transferred to the Web server 145 via the eNodeB device 194 and the packet transfer control device 190, the second portable terminal 170_2 starts downloading desired content data from the Web server. At this time, the packet transfer control device 190 can also send the connection request signal with parameters such as Web traffic, desired QoS class, MBR, and GBR added to the PCRF device 191.
In addition to the IP address and port number of the mobile terminal, the PCRF device 191 provides Web traffic, desired QoS class, MBR (Maximum Bit Rate), GBR to the user B using the second mobile terminal 170_2, if necessary. Parameters such as (Guaranteed Bit Rate) are input from the packet transfer control device 190. The PCRF device 191 reads the user profile information of the second portable terminal 170_2 from the user database, and generates a QoS parameter for QoS control.
Specifically, the QoS parameters are QCI (Quality Class Identifier) which is a value for identifying a QoS class, ARP (Allocation and Retention Priority) indicating the priority of resource reservation and retention, MBR, and GBR. Here, the MBR and GBR are used as they are when received from the packet transfer control device 190, and are generated by the PCRF device 191 when there is no reception.
The PCRF device 191 generates at least one of these four types of QoS parameters in the downlink direction, and sends the generated QoS parameters to the packet transfer control device 190. For the second portable terminal 170_2, since the user profile is “standard member”, “allows QoS downgrade during network congestion”, and because it is Web traffic, the PCRF device 191 As the values of these QoS parameters in the downlink direction, for example, QCI = 6 (TCP-based www), ARP = 6, GBR = 512 kbps, and MBR = 1 Mbps are set.
Next, the configuration of the packet transfer control device 190 will be described with reference to FIG. As shown in FIG. 2, the packet transfer control device 190 includes a packet transfer unit 176, a transfer control unit 188, a congestion detection unit 200, a control unit 211, and a rate control unit 230.
In FIG. 2, the control unit 211 relays a control signal from the first mobile terminal 170_1 to the SIP server 110, and relays a control signal and an Ack signal from the SIP server 110 to the first mobile terminal 170_1. In addition, the control unit 211 receives a connection request signal from the second portable terminal 170_2, and exchanges a control signal with the Web server 145. Further, the control unit 211 inputs at least one of four types of QoS parameters of QCI, ARP, MBR, and GBR for each traffic data from the PCRF device 191.
Here, in the first embodiment, since two types of traffic, that is, voice call traffic and Web content download data traffic, are generated, the control unit 211 controls the uplink and downlink directions of the voice call traffic. At least one of the four types of QoS parameters and at least one of the four types of QoS parameters for the downlink direction of the download data traffic are input from the PCRF device 191. The control unit 211 sends these QoS parameters to the rate control unit 230.
The congestion detection unit 200 checks the ECN (Explicit Congestion Notification) field of the IP header for the upstream packet transmitted from the first mobile terminal 170_1 and the second mobile terminal 170_2 via the packet transfer unit 176. . When the ECN field has a predetermined value, the congestion detection unit 200 detects that the downlink direction from the eNodeB device 194 to the mobile terminal is in a congestion state, and provides downlink detection information indicating the detection result. To the control unit 211 and the rate control unit 230. The control unit 211 sends the congestion detection information to the PCRF device 191 in FIG.
When the PCRF device 191 in FIG. 1 inputs the congestion detection information from the control unit 211 in FIG. 2, the user profile for each of the first mobile terminal 170_1 and the second mobile terminal 170_2 currently connected to the eNodeB device 194 is obtained. Check at least one of information and QoS information. Here, the case where both are checked is shown as an example.
According to the user profile information, the PCRF device 191 recognizes that the first portable terminal 170_1 is a “premier member” and “does not allow downgrade during network congestion”. As described above, the QoS parameters of the first mobile terminal 170_1 are QCI = 1 (Conversational Voice), ARP = 2, GBR = 12.2 kbps, and MBR = 22.8 kbps for both uplink and downlink. On the other hand, for the second mobile terminal 170_2, according to the user profile information, the PCRF device 191 confirms that the second mobile terminal 170_2 is a “standard member” and “downgrade QoS when network congestion occurs. Recognize that you allow. As described above, the QoS parameters of the second portable terminal 170_2 are the downlink direction, QCI = 6 (TCP-based www), ARP = 6, and MBR = 1 Mbps.
Therefore, by comparing QCI and ARP among user profile information and QoS information, in particular, the PCRF device 191 sets the change flag = 0 without changing the QoS parameter for the first mobile terminal 170_1, It is determined to change the QoS parameter for the second portable terminal 170_2. Here, as an example, QCI = 6 (TCP-based www), ARP = 6, BBR = 256 kbps, MBR = 512 bps are changed and the change flag = 1 is set for the second portable terminal 170_2. Then, the PCRF device 191 sends the QoS parameter and the change flag related to the first mobile terminal 170_1 to the control unit 211 of the packet transfer control device 190. Furthermore, the PCRF device 191 sends the QoS parameter and the change flag related to the second portable terminal 170_2 to the control unit 211 of the packet transfer control device 190.
Returning to FIG. 2, the rate control unit 230 inputs congestion detection information from the congestion detection unit 200, and inputs a QoS parameter and a change flag from the control unit 211.
Here, the configuration of the rate control unit 230 will be described with reference to FIG. The rate control unit 230 includes a congestion identification unit 231, a flag identification unit 232, a QoS parameter identification unit 233, and a rate change setting unit 234.
In FIG. 3, the congestion identifying unit 231 receives the congestion detection information, identifies that congestion has occurred in the downlink direction, and sends an instruction to change the rate setting in the downlink direction to the rate change setting unit 234.
The flag identifying unit 232 inputs a change flag related to the QoS parameter for the first mobile terminal 170_1 and a change flag related to the QoS parameter for the second mobile terminal 170_2, and indicates that there is a change in the QoS parameter for the second mobile terminal 170_2. Recognizing and sending an instruction to change the rate setting for the second portable terminal 170_2 to the rate change setting unit 234.
The QoS parameter identification unit 233 inputs the QoS parameter for the first mobile terminal 170_1 and the QoS parameter for the second mobile terminal 170_2, and there is no change in the QoS parameter for the first mobile terminal 170_1. Of the QoS parameters for portable terminal 170_2, it is recognized that GBR and MBR have been changed (reduced). Then, the QoS parameter identification unit 233 sends these QoS parameters for the second portable terminal 170_2 to the rate change setting unit 234.
In this example, it is assumed that the request for an appropriate rate is a rate reduction request.
Based on the input values from the congestion control unit 231, the flag identification unit 232, and the QoS parameter identification unit 233, the rate change setting unit 234 has a downlink rate for the second portable terminal 170_2 exceeding 256 kbps set by GBR. The rate reduction request is output to the transfer control unit 188 in FIG. 2 so that the maximum rate does not exceed 512 kbps set by the MBR.
The transfer control unit 188 in FIG. 2 issues an instruction to perform transfer control as it is to the packet of the first portable terminal 170_1 because there is no change in the QoS parameter, and the packet of the second portable terminal 170_2 Thus, in order to adapt to the change (reduction) of the GRB in the downlink direction and the change (reduction) of the MBR, the packet transfer unit 176 sets the content rate for the uplink request of the second portable terminal 170_2. Change to 256 kbps or less. For example, when the SIP / SDP (Session Description Protocol) or the RTSP (Real Time Streaming Protocol) / SDP is used for the content request from the second portable terminal 170_2, the transfer control unit 188 uses “B = "The packet transfer unit 176 is instructed to change the field to a numerical value of 256 kbps or less.
In addition, the transfer control unit 188 specifies an appropriate file when specifying a bit rate of 256 kbps or less in the case of a request by, for example, HTTP (Hyper Text Transfer Protocol), or holding a plurality of files having different bit rates for the same content The packet transfer unit 176 is instructed to specify a file name having a bit rate of 256 kbps or less as a size specification or to notify a file name having a file size of 256 kbps or less.
The packet transfer unit 176 in FIG. 2 receives the instruction signal from the transfer control unit 188 and operates as follows.
That is, the packet transfer unit 176 does not change the first portable terminal 170_1, and for the uplink and downlink packets, QCI = 1 (Conversational Voice), ARP = 2, GBR = 12.2 kbps. , MBR = 22.8 kbps is preferentially transferred.
On the other hand, for the second mobile terminal 170_2, the packet transfer unit 176, for the upstream packet, for the packet relayed by the packet transfer unit 176, for example, SIP / SDP or RTSP / When SDP is used, it is transmitted after rewriting the “b =” field of the SDP portion to a numerical value of 256 kbps or less. Also, the packet transfer unit 176 has been rewritten to specify a bit rate of 256 kbps or less in the case of, for example, an HTTP request, or to specify a file name having a bit rate of 256 kbps or less when the file name differs depending on the bit rate. Send out above.
Further, the packet transfer unit 176 changes QBR = MB (256-kbps, MBR = 512 bps) with QCI = 6 (TCP-based www) and ARP = 6 as it is for the downstream packet. After that, the packet is transferred.
Although the description of the configuration of the first embodiment of the present invention has been completed above, various modifications are possible.
In the first embodiment, the case of performing a voice call and downloading Web contents has been described, but real-time communication and data download can be used for other services with the same configuration. For example, the same configuration can be applied to a TV phone and content download.
In the first embodiment, ECN information is used to detect congestion, but other information can also be used. As another configuration, the packet transfer control device 190 can input congestion information directly from the eNodeB device 194. Specifically, when the eNodeB device 194 detects downlink congestion, an egress packet from the first mobile terminal 170_1 or the second mobile terminal 170_2 is stored in the ECN field of the IP header of the packet. By setting the CE bit and sending it to the packet transfer control device 190, the congestion detection unit 200 of the packet transfer control device 190 can detect congestion.
Although the congestion detection unit 200 and the rate control unit 230 are built in the packet transfer control device 190, they can be external devices.
Further, the function of the PCRF device 191 can be built in the packet transfer device 190.
The mobile network 150 may be a 3G network, and the packet transfer control device 190 may be an SGSN (Serving GPRS Support Node) or a GGSN (Gateway GPRS Support Node).
The packet transfer control device 190 can be realized by a program executed by a computer. That is, the packet transfer control device 190 may be composed of a packet transfer control processor (not shown) and a storage device (not shown). The storage device stores a packet transfer control program. In this case, the packet transfer control processor performs the above-described packet transfer control operation according to the packet transfer control program stored in the storage device.
Next, effects of the first exemplary embodiment of the present invention will be described.
According to the first embodiment of the present invention, when the bandwidth of the LTE / EPC network changes in time depending on the change in the amount of traffic over time, and when an unexpected event or popular content is When the traffic changes significantly compared to the statistical value due to the input or the start of new use by the heavy user, it becomes possible to avoid a congestion state that is difficult to avoid with the conventional control method. As a result, there is an effect that it is possible to avoid QoE (Quality of Experience) degradation such as sound being interrupted or screen being frozen at a terminal for a preferential user. Furthermore, even if services such as high sound quality VoIP and high resolution TV phone are started in the future using the packet communication path of the LTE / EPC system, it is possible to avoid deterioration of QoE on the terminal side. is there.
[Second Embodiment]
Next, the configuration of a communication system according to the second embodiment of the present invention will be described with reference to FIG. As will be described later, the illustrated communication system is different only in the packet transfer control device, and the other configuration is the same as the configuration of the communication system according to the first embodiment shown in FIG. Accordingly, reference numeral 190A is assigned to the packet transfer control device.
FIG. 5 is a block diagram showing a configuration of the packet transfer control device 190A. In FIG. 5, the constituent elements having the same numbers as those in FIG. 2 perform the same operations as those in FIG.
The packet transfer control device 190A is the same as the packet transfer control device 190 shown in FIG. 2 except that the bandwidth measuring unit 205 is added and the operation of the congestion detection unit is changed as will be described later. It has a configuration. Accordingly, reference numeral 210 is assigned to the congestion detection unit.
In FIG. 5, the bandwidth measuring unit 205 calculates at least one bandwidth of the network to which the first mobile terminal 170_1 and the second mobile terminal 170_2 are connected at the time of session connection or at predetermined time intervals. .
The bandwidth measuring unit 205 uses the transmission packet from the packet transfer unit 176 and the return packet from the mobile terminal 170 to determine the upstream bandwidth and the downstream bandwidth for the network connected to the mobile terminal 170. At least one is measured. In the present embodiment, a configuration in the case of measuring both upstream and downstream bands will be described.
First, the bandwidth measuring unit 205 instructs the packet transfer unit 176 to send a plurality of specific packets (probe packets) at a predetermined timing. In accordance with the instruction, the packet transfer unit 176 directs a plurality of specific packets to the first portable terminal 170_1 or the second portable terminal 170_2 at the timing when the instruction is received, and continuously in a predetermined order. And send it out.
Here, the plurality of packets indicates two or more packets. The sending order is a predetermined order. For example, packets are sent in order from a packet having a small data size to a packet having a large data size. Further, the time interval between the packet and the next packet is a predetermined time interval. Here, for example, RTP / UDP (user datagram protocol) / IP is used as the protocol.
Next, the packet transfer unit 176 receives a reply packet from the first portable terminal 170_1 or the second portable terminal 170_2 as a result of sending the plurality of packets. Hereinafter, the reply packet from the first portable terminal 170_1 will be described, but the reply packet from the second portable terminal 170_2 has the same configuration.
Here, the reply packet includes, for example, the first mobile terminal 170_1, the packet number that can be received below the threshold with respect to the differential delay, the data size of the packet, the time when the packet was transmitted from the server, Information such as the time when the packet is received by the mobile terminal is included.
The packet transfer unit 176, from the reply signal received from the first mobile terminal 170_1, the number of the packet that the first mobile terminal 170_1 has received below the delay difference threshold, the transmission time from the server, the mobile terminal Are received, and are sent to the bandwidth measuring unit 205.
The bandwidth measuring unit 205 receives the above information from the packet transfer unit 176 and calculates the network bandwidth.
The bandwidth measuring unit 205 uses the first mobile terminal 170_1 to receive the packet number that has been received below the delay difference threshold, the data size of the packet, the transmission time of the packet from the server, and the mobile terminal of the packet. Is received, and the downstream bandwidth W_d is calculated according to the following equation (1).
D (N) / W_d = R (N) -R (N-1) (1)
In the above equation (1), D (N) represents the data size of the Nth packet transmitted from the packet transfer unit 176. Here, N and D (N) indicate the number and data size of a packet that can be received by the first portable terminal 170_1 below the delay difference threshold value, respectively. R (N) is the reception time at the first portable terminal 170_1 of the Nth packet sent from the server, and R (N-1) is the number of the (N-1) th packet sent from the server. Each reception time at one mobile terminal 170_1 is shown.
Next, the bandwidth measuring unit 205 smoothes the downstream bandwidth measurement value W_d temporally according to the following equation (2) to calculate B (n) _d.
B (n) _d = (l−β) * B (n−1) _d + βW_d (2)
Here, B (n) _d indicates a downstream band measurement value after smoothing at the nth time, and β is a constant in a range of 0 <β <1. Note that the time direction smoothing according to the equation (2) may not be performed if unnecessary.
Next, from the first portable terminal 170_1, a plurality of specific packets are directed to the packet transfer control device 190A at any timing after the connection request or when the reply signal is transmitted. Thus, by continuously sending out in time, the upstream band is measured in the packet transfer control device 190A. Here, the plurality of packets indicates two or more packets. The sending order is a predetermined order. For example, packets are sent in order from a packet having a small data size to a packet having a large data size. Further, the time interval between the packet and the next packet is a predetermined time interval. Here, for example, RTP / UDP / IP is used as the protocol.
The bandwidth measuring unit 205 receives a plurality of packets sent from the first portable terminal 170_1 from the packet transfer unit 176, and receives the packet number that has been received below the delay difference threshold, the data size of the packet, Information on the transmission time of the packet from the portable terminal and the reception time of the packet at the packet transfer unit 176 is input, and the upstream bandwidth W_u is calculated according to the following equation (3).
D (M) / W_u = P (M) -P (M-1) (3)
Next, the bandwidth measuring unit 205 smoothes the bandwidth measurement value W_u in the upstream direction temporally according to the following equation (4) to calculate B (n) _u.
B (n) _u = (l−β) * B (n−1) _u + βW_u (4)
The packet transfer unit 176 sends information necessary for network bandwidth measurement to the portable terminal 170 only at the time of session connection or at predetermined time intervals based on the time of session connection and session connection, for example. A response signal is received from the mobile terminal.
The bandwidth measuring unit 205 calculates B (n) _d and B (n) _u, for example, at predetermined time intervals, and outputs these to the congestion detection unit 210.
The congestion detection unit 210 performs the following determination to detect congestion.
1) Downlink bandwidth calculation B (n) _d ≧ If GBR + α in the downlink direction of the voice call by the first portable terminal 170_1, the congestion detection unit 210 determines what is the downlink QoS parameter for the first portable terminal 170_1. Is also notified to the PCRF apparatus 191 in FIG. 4 via the control unit 211. Here, α is a margin, and a predetermined value is used. In this case, the congestion detection unit 210 notifies the PCRF device 191 that the QoS parameter is not changed even for the second portable terminal 170_2.
2) Congestion detection in the case of GBR + α <B (n) _d <GBR + γ related to Web content by the second portable terminal 170_2 (where γ is a predetermined value) in the downlink direction of voice call by the first portable terminal 170_1 The unit 210 determines that the second portable terminal 170_2 is congested, and notifies the PCRF device 191.
3) If B (n) _d <GBR + α in the downlink direction of the voice call, the congestion detection unit 210 detects the congestion and notifies the PCRF device 191 of the information indicating the congestion.
4) Concerning the uplink direction, the congestion detection unit 210 determines the same as in 1) and 3) above, and notifies the PCRP device 191 whether or not congestion is detected.
Returning to FIG. 4, when the PCRP apparatus 191 receives the congestion detection information from the congestion detection unit 210 in FIG. 5, the user profile information and the QoS parameter of each of the first portable terminal 170_1 and the second portable terminal 170_2. Check at least one.
As described above, the QoS parameters for the first mobile terminal 170_1 are QCI = 1 (Conversational Voice), ARP = 2, GBR = 12.2 kbps, MBR = 22.8 kbps for both the uplink and downlink, As described above, the QoS parameters for the portable terminal 170_2 are the downlink direction, QCI = 6 (TCP-based www), ARP = 6, and MBR = 1 Mbps. Among these parameters, in particular, when QCI and ARP are compared, the PCRP device 191 shows that the first mobile terminal 170_1 has priority over the second mobile terminal 170_2.
Accordingly, the PCRF device 191 further refers to the user profile information, recognizes that the first portable terminal 170_1 is a “premier member”, and “does not allow downgrade at the time of network congestion”. The QoS parameter for the portable terminal 170_1 is not changed. On the other hand, the PCRF device 191 changes the QoS parameter for the second mobile terminal 170_2 because it recognizes that the second mobile terminal 170_2 is a “standard member” and “allows downgrade when network congestion occurs. Here, as an example, the PCRF device 191 changes the QCI = 6 (TCP-based www), ARP = 6, GBR = 256 kbps, MBR = 512 bbs with respect to the second portable terminal 170_2. The changed QoS parameters are sent to the packet transfer control device 190 A. Specifically, the changed QoS parameters are sent to the rate control unit 230 via the control unit 211 of FIG.
FIG. 6 is a block diagram illustrating a configuration of the first mobile terminal 170_1. The second portable terminal 170_2 has the same configuration, and thus description thereof is omitted.
The first portable terminal 170_1 includes a packet transmission / reception unit 250, a text decoder 251, an image codec 252, an audio codec 253, a delay difference determination unit 255, and a screen display unit 256.
In FIG. 6, the packet transmitting / receiving unit 250 generates a reply packet for the received probe packet and sends the generated reply packet to the network. Here, the reply packet is generated as follows, for example.
The packet transmission / reception unit 250 receives each of the plurality of probe packets transmitted from the packet transfer unit 176 in FIG. 5 and outputs the received packet to the delay difference determination unit 255.
The delay difference determination unit 255 measures the delay time T (n) for each packet by the following equation (5).
T (n) = R (n) -S (n) (5)
Here, T (n), R (n), and S (n) indicate the delay time of the nth packet, the reception time of the nth packet, and the transmission time of the nth packet, respectively. .
Further, the delay difference determination unit 255 calculates the delay difference τ (n) between the packets by the following equation (6).
τ (n) = T (n) −T (n−1) (6)
Here, τ (n) represents the delay difference of the nth packet.
Next, the delay difference determination unit 255 uses τ (n) to determine whether or not the delay difference exceeds a predetermined threshold value. If τ (n) ≧ Th3, the delay difference determination unit 255 determines that the delay difference has exceeded the threshold value in the nth packet. Here, Th3 is a predetermined threshold value. Then, the delay difference determination unit 255 sends the packet number N immediately after the delay difference exceeds the threshold value to the packet transmitting / receiving unit 250.
The packet transmission / reception unit 250 receives the packet number N from the delay difference determination unit 255, the packet number N immediately after the delay difference exceeds the threshold, the data size of the Nth packet, the (N−1) th The data size of each packet, the reception time and transmission time of each packet are stored in the payload of the reply packet, and then transmitted to the packet transfer control device 190A via the eNodeB device 194 in FIG.
Here, the threshold value Th3 may be determined in advance, or may be determined each time after looking at a series of values of τ (n).
Also, other methods can be used as the discrimination method. For example, T (n) may be compared with a threshold value, and n when the threshold value is exceeded may be set to N.
In FIG. 6, a voice codec 253 is used during a voice call. The text decoder 251 and the image codec 252 are used for decoding Web contents in which text and images are mixed. The text decoder 251 and the image codec 252 decode the text and images and output them to the screen display unit 256. The screen display unit 256 displays on the mobile terminal display. To do.
This is the end of the description of the configuration of the second exemplary embodiment of the present invention, but various modifications are possible.
For example, another algorithm can be used as the band measurement algorithm in the band measurement unit 205 of FIG. In the above embodiment, the bandwidth measuring unit 205 calculates the bandwidth based on the response signal from the mobile terminal, but the bandwidth measuring unit 205 measures the amount of delay with the mobile terminal and based on this, It can also be calculated.
The bandwidth measuring unit 205 does not measure the bandwidth by sending a probe packet for bandwidth measurement from the packet transfer unit, but uses a response signal from the mobile terminal without using the probe packet. It can also be used. In this case, the delay difference determination unit 255 in FIG. 6 is unnecessary.
In the second embodiment, the bandwidth measurement unit 205, the congestion detection unit 210, and the rate control unit 230 are built in the packet transfer control device 190A, but at least one of them is an external device. You can also.
The packet transfer control device 190A can be realized by a program executed by a computer. That is, the packet transfer control device 190A may be composed of a packet transfer control processor (not shown) and a storage device (not shown). The storage device stores a packet transfer control program. In this case, the packet transfer control processor performs the above-described packet transfer control operation according to the packet transfer control program stored in the storage device.
Next, effects of the second exemplary embodiment of the present invention will be described.
According to the second embodiment of the present invention, when the bandwidth of the LTE / EPC network changes in time depending on the change in the amount of traffic over time, and when an unexpected event or popular content When the traffic changes significantly compared to the statistical value due to the input or the start of new use by the heavy user, it becomes possible to avoid a congestion state that is difficult to avoid with the conventional control method. As a result, there is an effect that it is possible to avoid QoE (Quality of Experience) degradation such as sound being interrupted or screen being frozen at a terminal for a preferential user. Furthermore, even if services such as high sound quality VoIP and high resolution TV phone are started in the future using the packet communication path of the LTE / EPC system, it is possible to avoid deterioration of QoE on the terminal side. is there.
Although the present invention has been described with reference to the embodiments, the present invention is not limited to the above embodiments. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention.
A part or all of the above-described embodiment can be described as in the following supplementary notes, but is not limited thereto.
(Appendix 1)
A packet transfer control device for connecting a terminal via a network and transferring a packet storing media data in response to a request from the terminal,
A congestion detection unit for detecting congestion of the network;
When the congestion detection unit detects congestion of the network, based on at least one of the user profile information and QoS information, a notification requesting an appropriate rate of content is sent in the upstream direction, and the QoS information is included in the QoS information. A transfer control unit for controlling the transfer of the packet based on;
A packet transfer control device comprising:
(Appendix 2)
The packet transfer control device according to appendix 1, wherein the congestion detection unit extracts congestion information from an upstream packet and detects congestion of the network.
(Appendix 3)
Based on a reply response signal from the terminal to the packet sent from the packet transfer control device, further comprising a bandwidth measuring unit that calculates the bandwidth of the network as a calculated value,
The packet transfer control device according to appendix 1, wherein the congestion detection unit detects congestion of the network based on the calculated value.
(Appendix 4)
The packet transfer control device according to any one of appendices 1 to 3, wherein the media data includes at least one of audio data, video data, text data, and content data.
(Appendix 5)
A communication system comprising: the packet transfer control device according to any one of appendices 1 to 4; and the terminal connected to the packet transfer control device via the network.
(Appendix 6)
A PCRF device for generating a QoS parameter for QoS control based on at least one of the user profile information and the QoS information;
When the congestion detection unit detects congestion in the network, the transfer control unit sends a notification requesting the content with the appropriate rate based on the QoS parameter in the upstream direction, and sets the QoS parameter to 6. The communication system according to appendix 5, which controls transfer of the packet based on the above.
(Appendix 7)
The communication system according to appendix 6, wherein the QoS parameter is at least one of QCI, ARP, MBR, and GBR.
(Appendix 8)
A packet transfer control device for connecting a terminal via a network and transferring a packet storing media data in response to a request from the terminal,
A congestion detection unit for detecting congestion of the network;
When the congestion detection unit detects congestion of the network, based on at least one of the user profile information and the QoS information, a notification requesting content having an appropriate file size is sent in the upstream direction, and the QoS information A transfer control unit for controlling the transfer of the packet based on:
A packet transfer control device comprising:
(Appendix 9)
9. The packet transfer control device according to appendix 8, wherein the congestion detection unit extracts congestion information from an upstream packet and detects congestion of the network.
(Appendix 10)
Based on a reply response signal from the terminal to the packet sent from the packet transfer control device, further comprising a bandwidth measuring unit that calculates the bandwidth of the network as a calculated value,
9. The packet transfer control device according to appendix 8, wherein the congestion detection unit detects congestion of the network based on the calculated value.
(Appendix 11)
The packet transfer control device according to any one of appendices 8 to 10, wherein the media data includes at least one of audio data, video data, text data, and content data.
(Appendix 12)
A communication system including the packet transfer control device according to any one of appendices 8 to 11 and the terminal connected to the packet transfer control device via the network.
(Appendix 13)
A PCRF device for generating a QoS parameter for QoS control based on at least one of the user profile information and the QoS information;
When the congestion detection unit detects congestion of the network, the transfer control unit sends a notification requesting the content of the appropriate file size based on the QoS parameter in the upstream direction, and the QoS parameter 13. The communication system according to appendix 12, which controls transfer of the packet based on
(Appendix 14)
The communication system according to attachment 13, wherein the QoS parameter is at least one of QCI, ARP, MBR, and GBR.
(Appendix 15)
A packet transfer control method in a packet transfer control device for connecting a terminal via a network and transferring a packet storing media data in response to a request from the terminal,
A congestion detection step of detecting congestion of the network;
When congestion of the network is detected, a notification requesting an appropriate content rate is sent based on at least one of the user profile information and QoS information, and the packet information is sent based on the QoS information. A transfer control step for controlling the transfer;
A packet transfer control method including:
(Appendix 16)
16. The packet transfer control method according to supplementary note 15, wherein the congestion detection step extracts congestion information from an upstream packet and detects congestion of the network.
(Appendix 17)
Based on a reply response signal from the terminal to the packet transmitted by the packet transfer control device, further comprising a bandwidth measuring step for calculating the bandwidth of the network as a calculated value,
The packet transfer control method according to appendix 15, wherein the congestion detection step detects congestion of the network based on the calculated value.
(Appendix 18)
18. The packet transfer control method according to any one of appendices 15 to 17, wherein the media data includes at least one of audio data, video data, text data, and content data.
(Appendix 19)
A packet transfer control method in a packet transfer control device for connecting a terminal via a network and transferring a packet storing media data in response to a request from the terminal,
A congestion detection step of detecting congestion of the network;
When the congestion of the network is detected, a notification requesting content of an appropriate file size is sent in the upstream direction based on at least one of the user profile information and the QoS information, and the packet based on the QoS information is sent A transfer control step for controlling the transfer of
A packet transfer control method including:
(Appendix 20)
20. The packet transfer control method according to appendix 19, wherein the congestion detection step detects congestion of the network by extracting congestion information from an upstream packet.
(Appendix 21)
Based on a reply response signal from the terminal to the packet transmitted from the packet transfer control device, further comprising a bandwidth measurement step of calculating the bandwidth of the network as a calculated value,
The packet transfer control method according to appendix 19, wherein the congestion detection step detects congestion of the network based on the calculated value.
(Appendix 22)
The packet transfer control method according to any one of appendices 19 to 21, wherein the media data includes at least one of audio data, video data, text data, and content data.
(Appendix 23)
A computer-readable recording medium recorded with a packet transfer control program for transferring a packet storing media data in response to a request from the terminal to a computer connected to the terminal via a network, the packet transfer control program comprising: To the computer,
A congestion detection procedure for detecting congestion of the network;
When congestion of the network is detected, a notification requesting an appropriate content rate is sent based on at least one of the user profile information and QoS information, and the packet information is sent based on the QoS information. A transfer control procedure for controlling the transfer;
A computer-readable recording medium for executing
(Appendix 24)
A computer-readable recording medium recording a packet transfer control program for transferring a packet storing media data in response to a request from the terminal to a computer connected to the terminal via a network, wherein the packet transfer control program is To the computer,
A congestion detection procedure for detecting congestion of the network;
When the congestion of the network is detected, a notification requesting content of an appropriate file size is sent in the upstream direction based on at least one of the user profile information and the QoS information, and the packet based on the QoS information is sent A transfer control procedure that controls the transfer of
A computer-readable recording medium for executing

110 SIP server 130 IMS network 140 Internet network 145 Web server 150 Mobile network 170_1, 170_2 Portable terminal 176 Packet transfer unit 188 Transfer control unit 190, 190A Packet transfer control device 191 PCRF device 194 eNodeB device 205

Bandwidth measurement unit

200, 210 Congestion detection Unit 211 control unit 230 rate control unit 250 packet transmission / reception unit 251 text decoder 252 image codec 253 audio codec 255 delay difference determination unit 256 screen display unit This application is filed on November 29, 2012, Japanese Patent Application No. 2012 Claims priority based on -260635, the entire disclosure of which is incorporated herein.

Claims

A packet transfer control device for connecting a terminal via a network and transferring a packet storing media data in response to a request from the terminal,
A congestion detection unit for detecting congestion of the network;
When the congestion detection unit detects congestion of the network, based on at least one of the user profile information and QoS information, a notification requesting an appropriate rate of content is sent in the upstream direction, and the QoS information is included in the QoS information. A transfer control unit for controlling the transfer of the packet based on;
A packet transfer control device comprising:
2. The packet transfer control device according to claim 1, wherein the congestion detection unit extracts congestion information from an upstream packet and detects congestion of the network.
Based on a reply response signal from the terminal to the packet sent from the packet transfer control device, further comprising a bandwidth measuring unit that calculates the bandwidth of the network as a calculated value,
The packet transfer control device according to claim 1, wherein the congestion detection unit detects congestion of the network based on the calculated value.
The packet transfer control device according to any one of claims 1 to 3, wherein the media data includes at least one of audio data, video data, text data, and content data.
A communication system including the packet transfer control device according to any one of claims 1 to 4 and the terminal connected to the packet transfer control device via the network.
A packet transfer control device for connecting a terminal via a network and transferring a packet storing media data in response to a request from the terminal,
A congestion detection unit for detecting congestion of the network;
When the congestion detection unit detects congestion of the network, based on at least one of the user profile information and the QoS information, a notification requesting content having an appropriate file size is sent in the upstream direction, and the QoS information A transfer control unit for controlling the transfer of the packet based on:
A packet transfer control device comprising:
The packet transfer control device according to claim 6, wherein the congestion detection unit extracts congestion information from an uplink packet and detects congestion of the network.
Based on a reply response signal from the terminal to the packet sent from the packet transfer control device, further comprising a bandwidth measuring unit that calculates the bandwidth of the network as a calculated value,
The packet transfer control device according to claim 6, wherein the congestion detection unit detects congestion of the network based on the calculated value.
The packet transfer control device according to any one of claims 6 to 8, wherein the media data includes at least one of audio data, video data, text data, and content data.
A communication system including the packet transfer control device according to any one of claims 6 to 8 and the terminal connected to the packet transfer control device via the network.