KR100900308B1 - Method for classifying downstream packet in head-end Cable Modem Termination System providing channel bonding - Google Patents

Abstract

The present invention provides a method of extracting a destination media access control (MAC) address of a received data packet, the media access control (MAC) address of a cable modem to receive the data packet in a first classification table corresponding to the destination address, Obtaining memory address information of cable modem classifier identifiers (CLIDs) corresponding to a media access control (MAC) address, extracting cable modem classifier identifiers (CLIDs) information present in the memory address; Extracting a classifier pattern according to the extracted cable modem classifier identifier (CLIDs) information, generating a result pattern by combining the cable modem's media access control (MAC) address and classifier pattern, and the result pattern Extracting a memory address including downlink service flow information from a second classification table corresponding to the memory address; A method of classifying a packet in a cable modem termination system (CMTS) supporting a channel combining method comprising extracting downlink service flow information corresponding to the subframe and generating an output packet corresponding to the downlink service flow information and data packets. To provide.

CMTS (cable modem termination system), channel bonding, classification

Description

Method for classifying downstream packet in head-end Cable Modem Termination System providing channel bonding}

1 is a diagram illustrating a configuration of a cable network to which the present invention is applied.

2 is a diagram schematically illustrating processing of a downlink data packet in a cable modem termination system (CMTS) according to an embodiment of the present invention.

3 is a diagram schematically illustrating a structure of a downlink packet classifier according to an embodiment of the present invention.

4 is a diagram illustrating a reference scheme of various tables referenced by a downlink packet classifier according to an embodiment of the present invention.

5 is a flowchart illustrating an operation sequence of a downlink packet classifier according to an embodiment of the present invention.

6 illustrates a header portion added in a downlink packet classifier according to an embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

301: Downlink Packet Classifier

303: First classification table

305: second classification table

307: memory

311 Classifier Identifier (CLIDs) Table for Each Cable Modem

313: Classifier Pattern Table

315: Downlink service flow table

317: Downward Quality of Service (QoS) Table

The present invention relates to a method for classifying downlink packets in a MAC layer of a DOCSIS standard headend cable modem termination system (CMTS) supporting channel combining.

In a cable network conforming to the DOCSIS standard, downlink data packets input to a head-end cable modem termination system (CMTS) through a network interface must be transmitted on a channel that the cable modem can receive in order to be transmitted to a specific cable modem. . One downlink channel that can be transmitted to the cable modem can be a plurality of channels when supporting channel combining, and the downlink packets are scheduled into channels that can be transmitted to the cable modem by being divided into service flows according to respective service characteristics.

Therefore, the Headend Cable Modem Termination System (CMTS) must define and manage a classifier that can allocate service flows and classify service flows according to quality of service (QoS). In addition, according to a predefined classification rule, it is necessary to be able to quickly and effectively schedule data packets coming in through the downlink service flow to a transport channel reachable to the cable modem.

An object of the present invention is to classify a downlink packet in a cable modem termination system (CMTS) of a head end supporting a channel combining scheme.

In addition, the present invention finds the cable modem to which the packet is to be transmitted with the destination MAC address of the data packets input to the CMTS from the network interface, and the input packet according to the service flow classification rules of the cable modem to the characteristics per service flow Another object is to provide a method of classifying a specific service flow so that it can be delivered through a downlink channel.

In order to achieve the above object, according to an aspect of the present invention, extracting a destination MAC (Media Access Control) address of the received data packet, receiving the data packet in the first classification table corresponding to the destination address Acquiring memory address information of cable modem classifier identifiers (CLIDs) corresponding to a media access control (MAC) address of a cable modem to be connected and a media access control (MAC) address of the cable modem, and present in the memory address; Extracting the cable modem classifier identifier (CLIDs) information; extracting a classifier pattern corresponding to the extracted cable modem classifier identifier (CLIDs) information; Access Control) combining the address and the classifier pattern to generate a result pattern, corresponding to the result pattern Extracting a memory address including downlink service flow information from the second classification table, extracting downlink service flow information corresponding to the memory address, and outputting the output packet corresponding to the downlink service flow information and the data packet A method of classifying a packet in a cable modem termination system (CMTS) that supports a channel combining scheme including generating may be provided.

In a preferred embodiment, the first classification table and the second classification table may be stored in a memory of a CAM (Content Address Memory) method. In addition, when the memory address information of the cable modem classification identifiers (CLIDs) corresponding to the media access control (MAC) addresses of the cable modems cannot be obtained from the first classification table, a service for broadcasting the data packet is provided. The output packet may be generated according to the flow information.

In addition, when there is no classifier pattern corresponding to the extracted Cable Modem Identifier (CLID) information, the MAC (Media Access Control) address of the cable modem and the Null | Generating a result pattern, extracting a memory address including downlink service flow information from a second classification table according to the result pattern, and extracting downlink service flow information corresponding to the memory address; can do. In addition, when the downlink service flow information does not exist in the second classification table corresponding to the result pattern, the output packet may be generated according to the broadcast service flow information.

In addition, if the downlink service flow information does not exist in the second classification table corresponding to the result pattern, check whether there is a cable modem classification identifier (CLIIDs) of the next priority in the result pattern, and if so, again. It may be characterized by extracting a result pattern of cable modem classifier identifiers (CLIDs) of next priority.

In addition, if there is a cable modem Classifier Identifier (CLIDs) of the next priority in the result pattern, and if it does not exist, the MAC (Media Access Control) address and the null | Generating a result pattern, extracting a memory address including downlink service flow information from a second classification table according to the result pattern, and extracting downlink service flow information corresponding to the memory address; can do. Further, the cable modem classifier identifier (CLIDs) information, the classifier pattern, and the downlink service flow information may include a media access control (MAC) address, a cable modem classifier identifier (CLIDs), and the cable modem of the cable modem, respectively. It may be characterized in that it is predetermined according to the result pattern. The downlink service flow information may include a downlink service flow identifier (SFID), a cable modem media access control (MAC) address, a downstream channel identifier (DSID), a downstream channel list (DS Lists), a packet type, It may be characterized by including a priority (priority) and quality of service (QoS).

 In addition, the Quality of Service (QoS) may include a maximum sustained traffic rate, a minimum reserved traffic rate, an assorted minimum reserved traffic rate, and a maximum standby time. It may be characterized by including the time (Maximum Latency) and the maximum rage (Peak Rage). The first classification table, the second classification table, the cable modem classifier identifier (CLIDs) information, the classifier pattern, and the downlink service flow information may be preset, an initial registration process of a cable modem, and a dynamic service. It may be characterized by the fact that it can be changed by address learning through change and musk data packet monitoring.

According to another aspect of the present invention, a downlink packet classifier for classifying the data packet and generating an output packet according to a classification rule of a preset service flow by receiving the data packet, and receiving the received data packet in the downlink packet classifier. Cable modem termination including a first classification table memory and a second classification table memory to refer to retrieve corresponding service flow information, and a general memory for extracting service flow information with reference to the first and second classification table memories. A system can be provided.

In a preferred embodiment, the general memory may include a cable modem classifier identifier (CLIDs) table, a classifier pattern table, a downlink service flow table, and downlink quality of service (QoS) table information. . In addition, the first classification table memory and the second classification table memory may be characterized in that the memory of the CAM (Content Address Memory) method.

According to another aspect of the present invention, a channel comprising extracting a destination address of a received data packet, and obtaining output service flow information of the data packet corresponding to the destination address to generate an output packet. In a combining scheme, a downlink packet classification method may be provided.

In a preferred embodiment, obtaining the address information of the memory including the intermediate identifier information in the first classification table corresponding to the destination address, downlink service flow information information in the second classification table corresponding to the intermediate identifier information The method may further include acquiring address information of a memory included in the memory and extracting downlink service flow information corresponding to the memory address of the second classification table. The intermediate identifier information may be a result pattern in which a classifier pattern corresponding to classifier identifier (CLID) information of the cable modem and a media access control (MAC) address of the cable modem are combined. .

According to another aspect of the present invention, a computer-readable recording medium having recorded thereon a program for classifying a downlink packet, wherein the program includes a program for executing the method of any one of claims 1 and 15. A computer readable recording medium can be provided.

Referring to another aspect of the present invention. An apparatus capable of operation including a memory, comprising: a processing unit and a memory storage device coupled to the processing unit, the memory storage device comprising: a plurality of memory devices for executing the method of claim 1; It is possible to provide a device capable of operation including a memory, characterized in that it is suitable for storing instructions.

Next, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram illustrating a configuration of a cable network to which the present invention is applied.

Referring to FIG. 1, a cable network according to the present invention receives data from a cable modem termination system (CMTS) 100 within a head-end of a cable network, thereby receiving a cable network (Hybrid Fiber Coaxial cable: HFC). It is delivered to the subscriber residence 140 through.

In this case, in the case of a cable modem termination system (CMTS) supporting the channel combining method according to the present invention, the data packets received through the network are classified by priority through the downlink packet classifier 101 and the classified data packets are classified by the scheduler. It is distributed through several channels.

Each packet data is then sent to the cable network 110 via a frequency divider / synthesizer, which is sent to the cable modem 120 of the subscriber's residence 140.

The frequency transmitter and tuner 121 of the cable modem 120 receiving the data packet receives the transmitted signal, and the downlink modulator 123 of the cable modem demodulates the modulated signal. Thereafter, the data packet processor 127 of the cable modem transmits the data packet to the data receiving terminal 130 of the subscriber's residence.

In the case of uplink transmission, the downlink transmission process is reversed using the uplink modulator 125 of the cable modem and the uplink demodulator 105 of the cable modem termination system (CMTS).

In this manner, one cable modem termination system (CMTS) device operates in conjunction with a plurality of cable modems. However, in the channel combining method, each cable modem does not use the same channel, and when the cable modem is initialized, the downlink packet classifier 101 of the cable modem termination system (CMTS) should classify the packets by channel.

2 is a diagram schematically illustrating the processing of a downlink data packet in a cable modem termination system (CMTS) according to an embodiment of the present invention.

Referring to FIG. 2, when a data packet is received, the downlink packet classifier 201 refers to data information included in a memory 203 including a packet classification table, according to a service flow set in advance in an input data packet. It is further included to transmit to the downlink MAC (Media Access Control) scheduler (205).

The downlink packet classifier 201 sets a new header in the input packet to include classification information of the data packet inside the header. In addition, the information included in the header according to the service flow set by the downlink packet classifier 201 includes information about whether a channel combining method is used, a set of transmittable channels, a downstream service identifier (DSID), and a service flow identifier (SFID). And priority information.

The downlink media access control (MAC) packet scheduler 205 stores the data packet transmitted from the downlink service flow processing unit 301 into a packet type, a downstream identifier (DSID) to which the packet belongs, a priority, and a transmittable channel set. Therefore, it determines the channel through which the packet can be transmitted and plays the role of delivering data packet.

Through this process, the data packet is distributed and transmitted for each channel 207, and the data packet is sent again according to the priority for each channel 207, thereby enabling efficient data packet transmission in the channel combining scheme.

3 is a diagram schematically illustrating a structure of a downlink packet classifier according to an exemplary embodiment of the present invention.

Referring to FIG. 3, the downlink packet classifier 301 classifies a packet according to a classification rule of a preset service flow with respect to an input data packet, and includes classification information as internal header information of the packet, thereby downlinking MAC (Media Access Control). ) To the scheduler 205.

In order to classify the input data packet into the corresponding service flow, the first classification table 303 and the second classification table 305 are referred to in the present invention. The first and second classification tables are configured as a memory of a CAM (Content Address Memory) method to enable faster memory reference.

Information included in the general memory 307 may be quickly found by referring to the first and second classification tables, and the information included in the general memory 307 may be classified as a cable modem classifier identifier (CLIDs) table 311. , A classifier pattern table 313, a downlink service flow table 315, and a downlink quality of service (QoS) table 317.

These tables are all preset values according to the association of the media packet address of the data packet with the MAC address of the cable modem and the service flow information, and the media access control (MAC) address included in the data packet. The first and second classification tables may be used to determine a service flow identifier corresponding to the data packet, a priority for transmitting the packet, and a channel.

4 is a diagram illustrating a reference scheme of various tables referenced by a downlink packet classifier according to an embodiment of the present invention.

Referring to FIG. 4, first, a table referred to in a downlink packet classifier includes a first classification table 401, a second classification table 409, a cable modem classification identifier (CLIDs) table 403, and a classifier pattern table ( 405, a downlink service flow table 411, and a downlink quality of service (QoS) table 413.

The method of referring to these tables may be performed by first referring to the first classification table 401 through the destination media access control (MAC) address 421 of the data packet included in the input data packet. The classifier identifier according to the cable modem MAC (Media Access Control) address of the MAC (Media Access Control) address 423 and the cable modem MACID present in the general memory. The address 425 is obtained. Then, the cable modem classifier identifier (CLIDs) table 403 existing in the general memory according to the classifier identifier (CLIDs) address 425 of the cable modem found in the first classification table 401 is obtained. Reference to the Class Identifier (CLID) information 427 corresponding to the MAC (Media Access Control) address 425 of the cable modem is obtained. This Classifier Identifier (CLIDs) information 427 indicates the position of the classifier pattern table 403 and has a value of 0 to 63556.

When classifier identifier (CLIDs) information 427 is obtained as described above, a classifier pattern value applied to a service flow according to each packet is obtained accordingly. The classifier pattern is a value in which the classification criteria are formed into one bit pattern according to a grammar preset in the DOCSIS standard according to a quality of service (QoS) of the service flow.

When the classifier pattern is obtained by the classifier identifier (CLIDs) information 427, the media access control (MAC) address 423 and the classifier identifier (CLIDs) information 427 of the cable modem are obtained. Correspondingly, a result pattern 407 is generated, and this result pattern 407 is used to refer to the second classification table 409.

In the second classification table 409, the memory address 429 value of the downlink service flow information according to the result pattern 407 of the downlink service flow table 411 included in the general memory is determined according to the result pattern 407 value. Can be.

Using the memory address 429 value, the downlink service flow information matching the result pattern 407 is obtained from the downlink service flow table 411 stored in the general memory.

The downlink service flow information includes a downlink service flow identifier (SFID), a cable modem media access control (MAC) address, a downstream channel identifier (DSID), a downstream channel list (DS Lists: Downstream Lists), and a packet type. , Priority (priority) and quality of service (QoS),

Information included in the Quality of Service (QoS) is provided in detail in the downlink Quality of Service (QoS) attribute table 413, which includes the maximum sustained traffic rate and minimum retained traffic rate (QoS). There is a Minimum Reserved Traffic Rate, an Assumed Minimum Reserved Traffic Rate, a Maximum Latency, and a Peak Rage. However, this is not fixed. In some cases, a service pattern may be added with a new pattern syntax by defining additional service characteristics.

5 is a flowchart illustrating an operation sequence of a downlink packet classifier according to an exemplary embodiment of the present invention.

5, first, a packet is received (step 501). Thereafter, the destination MAC (Media Access Control) address included in the packet is extracted (step 503). Thereafter, a first classification table is referred to using the destination Media Access Control (MAC) address (step 505). As shown in FIG. 4, when the first classification table knows the destination media access control (MAC) address of the packet, the media access control (MAC) address and the cable modem classifier identifier of the destination cable modem to which the packet is transmitted are: You can get the address of the memory that contains the CLIDs information.

When the address information of the cable modem classifier identifiers (CLIDs) is obtained by using the first classification table, it is checked whether the cable modem classifier identifiers (CLIDs) exist by referring to the address (step 507). Cable modem Classifier Identifiers (CLIDs) are extracted (step 509). These cable modem classifier identifiers (CLIDs) indicate where the corresponding classifier pattern values exist. Accordingly, the classifier pattern value may be checked using the cable modem classifier identifiers (CLIDs) (step 511), and if present, the classifier pattern value may be extracted (step 513).

Thereafter, the extracted classifier pattern value and the MAC (Media Access Control) address of the cable modem are combined (step 515). The second classification table is searched using the combined result pattern (step 517). As shown in FIG. 4, the second classification table may know the address of the downlink service flow identifier value when the result pattern is known.

In this way, if the address of the downlink service flow identifier is extracted from the second classification table, it is checked whether there is information corresponding to the address (step 521), and if it exists, the corresponding downlink service flow information is extracted (step 521). Thereafter, a new header is added to the input data packet using the extracted downlink service flow information to generate an output packet (step 523), and the generated packet is transmitted to the outside (step 525).

On the other hand, if the classifier pattern value does not exist in step 511, the resultant pattern is generated by combining a media access control (MAC) address of the cable modem and a null classifier (step 533), and using the result pattern. In step 535, the second classification table is searched. At this time, if there is matching information, the process goes to step 521 to extract the downlink service flow information, and otherwise generates an output packet according to the broadcast service flow information (step 539).

In addition, if the information corresponding to the address value of the second classification table does not exist in step 519, it is checked whether the next-order cable modem classification identifier information exists among the cable modem classification identifier information (step 531). Proceeds from step 513 again, otherwise proceeds in the manner of reference step 533.

If no classification identifier information exists at step 507, the flow proceeds directly to step 539 to generate a broadcast service flow.

6 is a diagram illustrating a header portion added in a downlink packet classifier according to an embodiment of the present invention.

Referring to FIG. 6, the data packet received in the downlink service flow processor includes an 802.3 Media Access Control (MAC) packet 620. This is a data transmission standard set by the IEEE as a standard.

Upon receiving such a data packet, the downlink service flow processor adds a header 610 to be used inside the data packet processing apparatus to the packet.

The header 610 includes a data type part 601 for determining a data packet transmission method, a priority part 603 for indicating the priority of the packet, and a DSID (for downlink channel through which the packet can be transmitted). Downstream Identifier (605) portion, a List Mark portion 607 indicating a list of downlink channels to which a packet is to be transmitted, and a Service Flow Identifier (SFID) portion 609 indicating a service flow corresponding to the packet. Include.

The data type portion 601 consists of 8 bits and the priority portion 603 consists of 4 bits.

Priority portion 603 has a value of 0-7 and the larger the number, the higher the priority.

The Downstream Identifier (DSID) portion 605 is composed of 24 bits and is an identifier indicating a set of downlink channels that can be transmitted by the service flow processor.

The list mark portion 607 is composed of the same bits as the number of the downlink channel and displays a list of the downstream channel (DC). Each bit represents one channel and, for example, if it is desired to include the eighth downlink channel among all 32 channels, the bit of the eighth digit of the 32 bits is represented by one.

The SFID (Service Flow Identifier) portion 609 is an identifier of a service flow of an input packet.

The present invention is not limited to the above embodiments, and many variations are possible by those skilled in the art within the spirit of the present invention.

According to the present invention, it is possible to provide a method for classifying downlink packets in a cable modem termination system (CMTS) of a headend supporting a channel combining scheme.

In addition, the present invention finds a cable modem to which a packet is to be transmitted with destination MAC addresses of data packets inputted from the network interface to the CMTS, and sets the input packet according to service flow classification rules of the corresponding cable modem. In this way, a specific service flow may be classified and provided to be transmitted through a downlink channel.

Claims (19)

Extracting a destination media access control (MAC) address of the received data packet; A cable modem classifier identifier corresponding to a media access control (MAC) address of a cable modem to receive the data packet in a first classification table and a media access control (MAC) address of the cable modem corresponding to the destination address; Obtaining memory address information of CLIDs); Extracting the cable modem classifier identifier (CLIDs) information present in the memory address; Extracting a classifier pattern corresponding to the extracted cable modem classifier identifier (CLIDs) information; Generating a result pattern by combining a media access control (MAC) address of the cable modem and the classifier pattern; Extracting a memory address including downlink service flow information from a second classification table according to the result pattern; Extracting downlink service flow information corresponding to the memory address; And Adding a header including the downlink service flow information to the data packet Downlink packet classification method in the channel combining method comprising a. The method of claim 1, The first classification table and the second classification table are stored in a memory of a CAM (Content Address Memory) method. Downlink packet classification method in the channel combining method characterized in that. The method of claim 1, If the memory address information of the cable modem classifier identifier (CLIDs) corresponding to the media access control (MAC) address of the cable modem is not obtained from the first classification table, a header corresponding to the broadcast service flow information may be obtained. Adding to the data packet Downlink packet classification method in the channel combining method characterized in that. The method of claim 1, If there is no classifier pattern corresponding to the extracted Cable Modem Identifier (CLID) information, the result is obtained by combining the Media Mode Control (MAC) address of the cable modem and a null | Generating a pattern; Extracting a memory address including downlink service flow information from a second classification table according to the result pattern; And Extracting downlink service flow information corresponding to the memory address; Downlink packet classification method in the channel combining method further comprising. The method of claim 4, wherein If there is no downlink service flow information in the second classification table corresponding to the result pattern, adding a header corresponding to the broadcast service flow information to the data packet; Downlink packet classification method in the channel combining method characterized in that. The method of claim 1, If the downlink service flow information does not exist in the second classification table corresponding to the result pattern, check whether there is a cable modem classification identifier (CLIDs) having a next priority in the result pattern, and if so, the next priority Extract the resulting pattern of the cable modem Classifier Identifiers (CLIDs) of the ranks. Downlink packet classification method in the channel combining method characterized in that. The method of claim 6, In the result pattern, it is determined whether a cable modem Classifier Identifier (CLIDs) of a next priority is present. Generating a pattern; Extracting a memory address including downlink service flow information from a second classification table according to the result pattern; And Extracting downlink service flow information corresponding to the memory address; Downlink packet classification method in the channel combining method further comprising. The method of claim 1, The cable modem Classifier Identifier (CLIDs) information, the classifier pattern, and the downlink service flow information are respectively a media access control (MAC) address, a cable modem classifier identifier (CLIDs), and the result pattern of the cable modem. Predetermined according to Downlink packet classification method in the channel combining method characterized in that. The method of claim 1, The downlink service flow information includes a downlink service flow identifier (SFID), a cable modem media access control (MAC) address, a downstream channel identifier (DSID), a downstream channel list (DS Lists), a packet type, and a priority. including priority and quality of service (QoS) Downlink packet classification method in the channel combining method characterized in that. The method of claim 9, The quality of service (QoS) is Maximum Sustained Traffic Rate, Minimum Reserved Traffic Rate, Assumed Minimum Reserved Traffic Rate, Maximum Latency, and Peak Rage. Including Downlink packet classification method in the channel combining method characterized in that. The method of claim 1, The first classification table, the second classification table, the cable modem classifier identifier (CLIDs) information, the classifier pattern and the downlink service flow information may be preset, an initial registration process of a cable modem, a dynamic service change, and the like. Modifiable by address learning through musk data packet monitoring Downlink packet classification method in the channel combining method characterized in that. A downlink packet classifier configured to receive a data packet, classify the data packet according to a preset classification rule of a service flow, and add a header including service flow information to the data packet; A first classification table memory and a second classification table memory for referencing the received data packet by the downlink packet classifier to retrieve corresponding service flow information; General memory for extracting the service flow information with reference to the first and second classification table memory Cable modem termination system comprising a. The method of claim 12, The general memory includes a cable modem classifier identifier (CLIDs) table, a classifier pattern table, a downlink service flow table, and downlink quality of service (QoS) table information. Cable modem termination system characterized in that. The method of claim 12, The first classification table memory and the second classification table memory are CAM (Content Address Memory) type memory. Cable modem termination system characterized in that. Extracting a destination address of the received data packet; And Acquiring address information of a memory including intermediate identifier information in a first classification table corresponding to the destination address; Acquiring address information of a memory including downlink service flow information in a second classification table corresponding to the intermediate identifier information; Extracting downlink service flow information corresponding to a memory address of the second classification table; And Adding a header including the extracted downlink service flow information to the data packet; Downlink packet classification method in the channel combining method comprising a. delete The method of claim 15, The intermediate identifier information is A class pattern that combines the cable modem Class Identifier (CLIDs) information and the cable modem's Media Access Control (MAC) address. Downlink packet classification method in the channel combining method characterized in that. A computer-readable recording medium having recorded thereon a program for classifying downlink packets, The program, A computer-readable recording medium having recorded thereon a program for executing the method of claim 1. A device capable of operation including a memory, Processing unit and A memory storage device coupled to the processing unit, The memory storage device, An apparatus capable of operation comprising a memory storing a plurality of instructions for executing the method of claim 1.

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