KR20080035129A - The method and apparatus for classification according to the service flow of the ip packet - Google Patents

Abstract

A method and an apparatus for classifying packet data of each service flow in a communication system are provided to provide a service by service flows according to a service class included in an IP(Internet Protocol) header or a service label. When an IP packet arrives from an upper layer of a terminal, a classifier performs the first classification according to the first classification information of a header of the IP packet(500,502). The classifier checks whether the IP packet includes the second classification information(504). If the IP packet includes the second classification information, the classifier performs the second classification(506). The classifier checks whether detailed QoS(Quality of Service) information has been received from the upper layer(508). If there is detailed QoS information received from the upper layer, the classifier performs the third classification according to the detailed QoS(512) and transfers the IP packet together with a control message including the detailed QoS information to the second layer of the terminal.

Description

Method and Apparatus for Classification of Packet Data by Service Flow in Communication System

 Is a diagram illustrating a header structure of IPv4 according to the prior art.

 1B is a diagram illustrating a header structure of IPv6 according to the prior art.

2 illustrates a classifier according to a preferred embodiment of the present invention.

3 is a diagram illustrating an operation between a terminal and a network node when detailed QoS information arrives from an upper layer according to the first embodiment of the present invention.

4 is a diagram illustrating an operation between a terminal and a network node when detailed QoS information is requested from a classifier according to a second embodiment of the present invention.

5 is a packet classification procedure diagram of a classifier according to an exemplary embodiment of the present invention.

The present invention relates to a method and apparatus for classifying packets in a communication system, and more particularly, to a method and apparatus for efficiently classifying packets for a specific service.

In general, a service for a terminal in a wireless access network is provided by a scheduler according to a Quality of Service (QoS) class (calss) indicated in each packet.

Specifically, the base station is an example of information displayed on a packet received through an access network. For example, a base station may use a service type or a traffic class indicated in a header of an IP packet as an inter-layer primitive from an upper node or an upper layer. Or it is delivered through a message between nodes. Thereafter, the base station finally inputs the corresponding information to the scheduler so that the terminal performs the corresponding service.

Hereinafter, the IP packet header structure according to the prior art will be described with reference to FIGS. 1A and B.

Here, suppose that a terminal uses a differentiated service according to a higher quality of service (QoS), and a packet reaches a wireless access network through an IP (internet protocol) network.

1A is a diagram illustrating a header structure of IPv4 according to the prior art.

Referring to FIG. 1A, IPv4 includes version, IHL, Type of Service (ToS) 102, total length, identification and flags, fragment offset, presence Time to live, protocol 104, header checksum, source address, destination address, options. It consists of fields for padding.

The Type of Service 102 field includes an IP service type, which is information for quality of service that can be included in each packet. Here, since the remaining components except for the ToS 102 field and the protocol 104 field are parts not related to the present invention, description thereof is omitted, and each IP packet is regarded as a different session and session control is performed. Let's assume

The ToS 102 field of the IP header includes information such as one byte, that is, six bits of session control information representing a differentiated service code point (DSCP).

1.Expedited Forwarding Per Hop Behavior (PHF): Premium service, DSCP = 101110

2. AF Assured Forwarding PHB:

The AF forwarding PHB is classified as shown in Table 1 below according to three Drop Precedence (DP) and classes.

2-1.Table 1

Sub-Classes in AF Service

Drop Precedence Class 1 Class 2 Class 3 Class 4 Low 001010 010010 011010 100010 Medium 001100 010100 011100 100100 High 001110 010110 011110 100110

3. Best Effort:

 DSCP = 000000

1B is a diagram illustrating a header structure of IPv6 according to the prior art.

Referring to FIG. 1B, the IPv6 version includes a traffic class 106, a flow label 108, a payload length, a next header, and a hop limit. ), A source address, and a field for a destination address.

In the case of IPv6, it is possible to grasp information for the quality of service that can be included in each packet through the traffic class 106 field used in the same manner as the ToS 102 field of the IPv4. The flow label 108 is on the order of 20 bits. Here, the flow is used to receive a specific service by attaching a specific label to the IP packet or a continuous packet transmitted from the same sender. The specific service includes non-default QoS or real-time service.

 However, since a specific value defined like DSCP in IPv4 does not exist and a pseudo random number is used, it may vary from implementation to implementation.

As a result, in the case of the IPv6 according to the prior art operating as described above, when the service type is not used a well-known value which is frequently used in advance between the terminal and the base station, there is a problem that accurate information cannot be detected. .

Accordingly, an object of the present invention, which was devised to solve the problems of the prior art operating as described above, is more accurate in order to reduce resource waste on the air interface and not reduce the quality of service provided to the terminal. It is to provide a classification method and apparatus for each service flow that can grasp IP session information.

Still another object of the present invention is to provide a method and apparatus for classifying services by service flows to perform services according to service flows according to service labels having different values for each service class or implementation included in an IP header.

The method according to the embodiment of the present invention, which was created to achieve the above object, in a communication system, in a method for classifying packets,

Receiving packet data from an upper layer and acquiring classification information for receiving a specific service from the packet data;

And classifying the packet data for each service flow according to the classification information.

According to another aspect of the present invention, an apparatus for classifying a packet in a communication system includes:

Receiving packet data from the upper layer, to obtain the classification information to receive a specific service from the header of the packet data, and including a classifier for classifying the packet data by service flow according to the obtained classification information It features.

Hereinafter, with reference to the accompanying drawings will be described in detail the operating principle of the preferred embodiment of the present invention. Like reference numerals are used to designate like elements even though they are shown in different drawings, and detailed descriptions of related well-known functions or configurations are not required to describe the present invention. If it is determined that it can be blurred, the detailed description thereof will be omitted. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

The present invention configures a classifier for each service flow to perform a service for each service flow according to a service label included in an IP header or a service label having a different value for each implementation. That is, the classifier for each service flow extracts classification information for identifying a service flow through inter-layer primitives or inter-node message exchanges, and guarantees a specific service for consecutive packets. To this end, the classifier for each service flow is placed in an existing IP convergence layer, and inter-layer primitives of nodes including the IP convergence layer and messages exchanged between nodes are changed.

2 is a view showing a classifier according to a preferred embodiment of the present invention.

Referring to FIG. 2, the classifier 200 is located at the IP convergence layer corresponding to the layer 2.5. The IP convergence layer is a layer that performs an operation required for an IP related service to an existing media access control (MAC) layer to provide a current IP service.

The classifier 200 classifies the service flow of packets arriving in the access network in order to provide accurate services to terminals existing in the wireless access network.

● Primary classification:

After the classifier 200 performs a primary classification to determine whether to classify the packet into the same flow using the primary classification information included in the IP header of the received packet, the classifier 200 outputs output data A. FIG. At this time, the sender address information of the output data A on which the primary classification is performed is basically used as an identifier to classify the flow. The primary classification information is obtained through the service type field of the IP header when the IP header is IPv4, and through traffic class information of the IP header when the IP header is IPv6.

● Secondary classification:

 The classifier performs classification through the secondary classification information included in the IP header of the received packet, and then outputs output data B. The secondary classification information is obtained through a protocol field of the IP header when the IP header is IPv4 and from a service label field of the IP header when the IP header is IPv6.

In this case, the classifier performs the primary classification, and then performs the secondary classification when the protocol and the service label information is present in the IP header of the packet instead of sequentially performing the secondary classification. In the absence of information, tertiary classification is performed.

● Tertiary classification:

The classifier performs tertiary classification based on detailed QoS information.

That is, the primary classification and the secondary classification of the classifier perform the classification process based on the QoS information included in the IP header of the packet, and in the case of the third classification process, the classification process is performed by detailed QoS information not included in the header. Do this. In this case, the detailed QoS information is included when the data is delivered from the upper layer, or when the detailed QoS information does not arrive from the upper layer, the detailed QoS information is obtained by requesting the detailed QoS information from the layer where the classifier exists to the upper layer, and then tertiary classification. Perform the process.

3 is a diagram illustrating an operation between a terminal and a network node when detailed QoS information arrives from an upper layer according to the first embodiment of the present invention.

Referring to FIG. 3, the terminal is composed of layer 1 (300a), layer 2 (302a), layer 3 (306a), the network node is layer 1 (300b), layer 2 (302b), Layer 2.5 (304b) and layer 3 (306b). In this case, the network node includes a base station and a gateway.

In step 310, the layer 3 306b of the network transmits the data packet received from the upper layer to the classifier located in its layer 2.5 304b through a primitive. Then, the classifier located in the layer 2.5 (304b) extracts the classification information from the packet received from the layer 3 (306b). The classification information includes primary classification information including service type or traffic class information, secondary classification information including protocol or service label information, and tertiary classification information which is QoS information of a service received from an upper layer. do.

In step 312, the classifier determines whether the packet is the same flow (or session) based on the classification information extracted from the IP header of the data packet. In this case, when the classifier determines that the information received from the upper layer is insufficient, the classifier requests detailed QoS information from the upper layer.

In step 314, the classifier generates a control message necessary for session control to the service according to the QoS according to the determination result and transmits the control message to layer 2 302a of the terminal. In this case, the classifier identifies whether the packet is the same flow as the previously received packet or a new flow, and services the same session in the case of continuous flow. On the other hand, when classified as a new flow, the control message is identified as a new session and delivered to the terminal. The control message also includes layer 3 data, layer 2.5 data and QoS making parameters. The procedure for determining the flow of the packet by the classifier and the parameters are described in detail below.

In step 316, the classifier maintains an existing service session if the flow is the same as the previous packet according to the control message, and if the flow is different from the previous packet, establishes a new session with the terminal in the corresponding service and transmits data to be actually transmitted. To layer 2 302a of the terminal.

Hereinafter, a procedure of determining the packet flow of the classifier will be described in detail.

First, the classifier performs a primary classification based on the service type and traffic class information included in the IP header according to the IP version of the packet received from the upper layer. That is, the classifier classifies the packet as the same flow as the previous packet when the IP header includes service type (IPv4) or traffic class information (IPv6) according to the version of the IP packet. Otherwise, perform a primary classification to determine new flows. In this case, the sender address information of the packet is basically used as an identifier for classifying a flow.

Next, the classifier classifies the packet into the same flow through a protocol ID (for IPv4) or service label information (for IPv6) included in the IP header according to a version of the IP packet or a new flow. Perform secondary classification to determine whether to classify as.

Finally, the classifier performs the third classification using the host protocol and port information included in the upper header or detailed QoS information received from the upper layer. That is, if the classifier is classified into the same flow in the secondary classification process, even if the packet classified into the same flow through the primary classification process, the classifier is the host protocol and port information (QoS), which is QoS information delivered by the higher layer protocol. Performs a tertiary classification by being delivered by a higher protocol, such as the session initiation protocol.

Hereinafter, the parameters of the control message will be described in detail.

The layer 3 data is transmitted to layer 3 (306a) of the terminal in a data packet including the QoS information for service to the terminal. The 2.5 layer data is data including QoS information.

The QoS making parameter is a control message required for session control based on QoS information received from an upper layer in a classifier for each service flow located in layer 2.5. In addition, on the basis of the classifier located in the 2.5 layer, whether the same flow as the previous packet or a new flow is identified, and in the case of continuous flow, the service is regarded as the same session.

4 is a diagram illustrating an operation between a terminal and a network node when detailed QoS information is requested from a classifier according to a second embodiment of the present invention.

4, the terminal is composed of layer 1 (400a), layer 2 (402a), layer 3 (406a), the network node is layer 1 (400b), layer 2 (402b), Layer 2.5 (404b) and Layer 3 (406b). In this case, the network node includes a base station and a gateway. In this case, it is assumed that the network layer 2.5 (404b) receives an IP packet not including QoS information from an upper layer.

In step 410, the layer 2.5 404b of the network requests QoS information of the IP packet from the classifier 3 when the detailed information on the QoS of the IP packet is requested from the classifier. In step 411, the layer 3 406b transmits a response message including QoS information according to the request to the 2.5 layer 404b.

In step 412, the classifier generates a control message for controlling a corresponding service session based on the QoS information of the received response message and transmits the control message to layer 2 402a of the terminal. In this case, the classifier identifies whether the packet is the same flow as the previously received packet or a new flow, and services the same session in the case of continuous flow. On the other hand, when classified as a new flow, the control message is identified as a new session and delivered to the terminal. The control message also includes layer 3 data, layer 2.5 data and QoS making parameters. Since the classifier determines the flow of the corresponding packet and the parameters are the same as those of FIG. 3, detailed description thereof will be omitted.

In step 416, the classifier maintains an existing service session if the flow is the same as the previous packet according to the control message, and if the flow is different from the previous packet, establishes a new session with the terminal in the corresponding service and transmits data to be actually transmitted. To layer 2 402a of the terminal.

5 is a packet classification procedure diagram of a classifier according to an exemplary embodiment of the present invention.

Referring to FIG. 5, if an IP packet arrives from an upper layer in step 500, the classifier performs first classification based on primary classification information in a header of the IP packet in step 502.

In step 504, the classifier determines whether secondary classification information is included in the IP packet. Here, the secondary classification information is included in the protocol field or the flow label field according to the version of the IP packet. If the second classification information is not included as a result of the determination, the IP packet is delivered to the terminal 2 of the terminal together with the control message including the primary classification information of the IP packet.

If the classification result includes the secondary classification information, in step 506, the classifier performs the secondary classification according to the secondary classification information in the header of the IP packet, and proceeds to step 508.

In step 508, the classifier checks whether there is detailed QoS information received from a higher level. If there is no detailed QoS information, the process proceeds to step 510.

If there is detailed QoS information as a result of the checking, in step 512, the classifier performs the third classification according to the detailed QoS information, and in step 510, the IP packet together with the control message including the third classification information of the IP packet. To the layer 2 of the terminal. In this case, the classifier is a value that has already received detailed QoS information to a higher layer, or a value received by the classifier to a higher layer.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the scope of the following claims, but also by those equivalent to the scope of the claims.

In the present invention operating as described in detail above, the effects obtained by the representative ones of the disclosed inventions will be briefly described as follows.

In order to solve the problem of not being contiguous and not guaranteeing the correct quality of service, the present invention can identify packets having the same service flow in a network node as one flow, and the same and continuous service is provided for the same flow. By providing a classifier for transmitting the corresponding information in the control message so that the terminal can be provided with continuous and continuous service for the same flow.

Claims (14)

In a communication system, a method for classifying a packet, Receiving packet data from an upper layer and acquiring classification information for receiving a specific service from the packet data; And classifying the packet data for each service flow according to the classification information. The method of claim 1, wherein the service flow, The packet classification method of claim 1, wherein the packet data is transmitted from the same sender, and a specific label is attached to the packet data so that a specific service (non-default QoS or real-time service) can be provided. The method of claim 2, wherein the service flow, The packet classification method of claim 13, wherein a pseudo random number is used. The method of claim 1, wherein the classifying process comprises: If the received packet data is the same flow as the previous packet data, the existing service session is maintained, and if the flow is different from the previous packet, the session is newly established in the corresponding service and the data to be actually transmitted is transmitted to the terminal. The packet classification method, characterized in that. The method of claim 1, wherein the classification information, Primary classification information including service type or traffic class information included in the packet data header according to the IP version of the packet data, and a protocol or service included in the header of the packet data according to the IP version of the packet data. The packet classification method comprising secondary classification information including label information and tertiary classification information which is quality information of a service received from an upper layer. The method of claim 4, wherein the classification process comprises: Classifying the packet data according to primary classification information; And classifying the packet data secondly, when the second classification information is included in the header of the packet data. The method of claim 6, And if the results of the primary classification and the secondary classification are the same, classifying the packet data in a third manner. In a communication system, an apparatus for classifying a packet, Receiving packet data from the upper layer, to obtain the classification information to receive a specific service from the header of the packet data, and including a classifier for classifying the packet data by service flow according to the obtained classification information And said packet classification device. The method of claim 8, wherein the service flow, The packet classification apparatus of claim 1, wherein the packet data is transmitted from the same sender, and a specific label is attached to the packet data so that a specific service (non-default QoS or real-time service) can be provided. The method of claim 9, wherein the service flow, And a pseudo random number is used. The method of claim 8, wherein the classifier, If the received packet data is the same flow as the previous packet data, the existing service session is maintained, and if the flow is different from the previous packet, the session is newly established in the corresponding service and the data to be actually transmitted is transmitted to the terminal. The packet classification apparatus, characterized in that. The method of claim 8, wherein the classifier, Primary classification information including service type or traffic class information included in the packet data header according to the IP version of the packet data, and a protocol or service included in the header of the packet data according to the IP version of the packet data. And second classification information including label information and third classification information which is quality information of a service received from an upper layer. The method of claim 12, wherein the classifier, And classifying the packet data according to the primary classification information, and classifying the packet data in the case where the header classification of the packet data includes the secondary classification information. The method of claim 12, wherein the classifier, And when the result of the primary classification and the secondary classification is the same, classify the packet data in the third manner.

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