KR100579139B1 - IP Packet Forwarding Method and Apparatus for ATM Switch-based IP Router, And Routing System using them - Google Patents

Abstract

1. TECHNICAL FIELD OF THE INVENTION

The present invention relates to a high speed internet protocol packet forwarding apparatus for asynchronous transmission mode based switching system, a method thereof, and a routing system using the same.

2. The technical problem to be solved by the invention

The present invention provides a high speed internet protocol packet forwarding apparatus and method for an asynchronous transmission mode based switching system capable of reducing traffic bottlenecks and improving switching performance by introducing a fixed-length switching function and distributing an IP forwarding function. , To provide a routing system using them.

3. Summary of the Solution of the Invention

The present invention, in the asynchronous transmission mode (ATM) -based routing system, separates the Internet Protocol (IP) packet from the data frame input through the Ethernet / frame relay network, retrieves the destination address for the IP packet, Ethernet / frame relay (FR) input port processing means for splitting the packet into ATM cells and transmitting the packet to the switching means; An ATM input port processing means for extracting an ATM cell from a data frame input through an ATM network, searching for a destination address of an ATM cell according to the type of the extracted ATM cell, and transmitting the ATM address to the switching means; The switching means for switching the ATM cell transmitted from the Ethernet / frame relay input port processing means and the ATM input port processing means and transferring the same to an output port; Ethernet / frame relay output port processing means for combining and generating an ATM packet by combining the ATM cells transmitted from the switching means, and generating a data frame from the stored IP packet and transmitting the data frame to the destination address; ATM output port processing means for combining the ATM cell transmitted from the switching means to transmit to the destination address through a transmission line frame; And network processing means for distributing IP packet forwarding by distributing the IP forwarding information table to all input ports of the router.

4. Important uses of the invention

The present invention is used for IP address search and router.

Forwarding, routing device, IP packet, ATM network, Ethernet, frame relay network.

Description

High Speed Internet Protocol Packet Forwarding Apparatus for Asynchronous Transfer Mode Based Switching System and Its Routing System {IP Packet Forwarding Method and Apparatus for ATM Switch-based IP Router, And Routing System using them}

1 is a block diagram of an ATM-LAN backbone network using an ATM-based Layer 3 router to which the present invention is applied.

2 is a diagram illustrating an embodiment of an ATM based routing system according to the present invention;

Figure 3 is an embodiment configuration of an Ethernet / frame relay line input / output port processing apparatus according to the present invention.

Figure 4 is a block diagram of an embodiment of an ATM line input / output port processing apparatus according to the present invention.

Figure 5 is a structure diagram of the Ethernet / frame relay input / output port processing protocol stack applied to the present invention.

6 is a diagram illustrating a connection protocol stack structure from the ATM to the Ethernet / frame relay direction according to the present invention.

7 is a diagram illustrating a protocol stack structure in an Ethernet / frame relay to ATM connection direction according to the present invention.

8 is a block diagram of an embodiment of an IP packet forwarding apparatus according to the present invention;

9 is an IP packet forwarding function block diagram applied to the present invention.

FIG. 10 is a flowchart illustrating a high speed internet protocol packet forwarding method for an asynchronous transmission mode based switching system according to the present invention. FIG.

The present invention relates to an Internet Protocol (IP) packet forwarding apparatus in a router (hereinafter referred to as IP), a method thereof, and an input / output port processing apparatus of a router using the same. In particular, a fixed length switching function is introduced. The present invention relates to a high speed internet protocol packet forwarding apparatus and method for asynchronous transmission mode based switching system for distributing IP forwarding functions, and a routing system using the same.

In the conventional router, since the layer 3 processing function of IP forwarding is concentrated in one place in the system, when there is a lot of traffic forwarding the IP packet, a traffic bottleneck occurs and the packet processing time can be processed at the speed of the line. There is a problem that there is no problem, and the packet exchange performance as a high-speed router cannot be satisfied by adopting a method of exchanging IP packets of variable length.
As an example of a similar prior art related to the present invention, in the Internet protocol over asynchronous transmission mode approach, the IP protocol data transmission scheme in the "Internet protocol over asynchronous transmission mode approach for transmitting IP data from a terminal to a local / remote forwarding method. (Korean Patent Registration No. 1999-0048608, registered on July 5, 1999) (hereinafter referred to as "first prior art"), wherein the first prior art determines whether the received IP data is registered in a predetermined forwarding table. Therefore, if not registered in the forwarding table, by selecting the local / remote forwarding method according to the service type of the IP data, it is possible to efficiently use the network resources in the IP over ATM approach.
However, in view of the present invention, while the first prior art is a method of local / remote forwarding IP data from a terminal, the present invention provides a high-performance ATM based ATM switch including a fast layer 3 processing function. Regarding the router structure, a line card is used to route IP packets with a forwarding table. In addition, although the first prior art has an effect of efficiently using the network resources of the IP over ATM, the present invention is to configure a medium-sized Internet and data communication network requiring high-speed layer 3 processing rather than the efficiency of network resources. It has the effect of establishing a structural basis for the system.
As another example, "Ethernet access device for accommodating IP router function using ATM switch" provides an Ethernet access device for accommodating IP router function using ATM switch (Korean Patent Registration No. 1998-153944, registered on July 7, 1998) (Hereinafter referred to as a second prior art), wherein the second prior art can provide an IP multicasting function to a plurality of ATM subscribers by using a cell multicasting function of an ATM switch. Leave it open and provide ATM access for users who require new high-speed data transfer and processing.
However, in view of the present invention, the second prior art is a small size general ATM router structure in an ATM switch, which encapsulates an IP packet without having a separate forwarding table in the Ethernet subscriber card of the ATM switch. On the contrary, the present invention is an ATM switch-based high performance ATM-based router structure including a fast layer 3 processing function, which encapsulates an IP packet with a forwarding table in a line card. In addition, although the second prior art has an effect of providing an ATM switch access function to an existing Ethernet user, the present invention provides a system capable of constructing a large-scale Internet and data communication network requiring high-speed Layer 3 processing. It has the effect of laying a structural foundation.
As another example, a router device of an "Asynchronous Transfer Mode (ATM) network" for a DS1E class ATM router for providing a multi-point interconnection function of a distributed computer network, a host computer, a personal computer, etc. (Korean Patent Registration No. 1996-008509 (Registered on August 13, 1998) (hereinafter referred to as "third prior art"), which describes the general structure of a small router of DS1E class. On the contrary, the present invention includes a separate layer 3 processing function, and proposes a system structure for the optimal configuration and structure therebetween, so that a system capable of constructing a large-scale Internet and data communication network requiring high speed layer 3 processing is required. It has the effect of laying a structural foundation.
Accordingly, there is an urgent need for a method for efficiently processing Internet traffic by distributing and processing an IP forwarding function in a system.

The present invention has been proposed in order to meet the above requirements, by introducing a fixed-length switching function and distributed processing IP forwarding function, asynchronous transmission mode-based switching that can reduce the traffic bottlenecks and improve the switching performance An object of the present invention is to provide a high speed internet protocol packet forwarding apparatus for a system, a method thereof, and a routing system using the same.

That is, the present invention applies the EXACT-matching algorithm and the LPM-matching algorithm simultaneously when an IP packet is input from the input port of the high-speed router, searches the forwarding information table, and divides it into ATM cells. It forwards to the ATM switch fabric, and at the output port, IP packets are recombined by combining the cells received from the ATM switch fabric, stored in a queue by IP quality of service (QoS) class, and service of IP packets through a separate IP packet scheduler. An object of the present invention is to provide a high-speed Internet protocol packet forwarding apparatus and method and a routing system using the same for an asynchronous transmission mode-based switching system that delivers IP packets according to quality (QoS).

In order to achieve the above object, the present invention provides an Internet Protocol (IP) packet forwarding apparatus for an asynchronous transmission mode (ATM) based routing system, comprising: a payload for an IP packet (received IP packet) received from the outside; Storage means for storing destination header information, information on the encapsulation header, and IP forwarding information; IP decapsulation means for analyzing the encapsulation header information to separate data to be delivered to a receiving IP processing means; Receiving IP processing means for taking the destination header (DH) information and delivering it to IP forwarding means; The IP forwarding means for retrieving the IP forwarding information by using the destination header (DH) information transmitted from the receiving IP processing means to find IP address information (destination IP address information) for a destination and transmitting the same to the transmitting IP processing means. ; The transmission IP processing means for delivering an IP encapsulation value for the destination IP address information transmitted from the IP forwarding means to IP encapsulation means; And converting the encapsulation header (EH) information into encapsulation header (EH) information that can be processed at the destination, converting the received IP packet, and transmitting the converted IP packet to the destination. Characterized in that it comprises a migration means.

In addition, the present invention provides an IP packet forwarding method applied to an internet protocol (IP) packet forwarding apparatus for an asynchronous transmission mode (ATM) based switching system, by using a destination header (DH) of an IP packet received from the outside. Confirming whether the EXACT matching is successful by searching the EXACT matching table and the Longest Prefix Matching (LPM) matching table; As a result of the checking in the confirming step, if the EXACT matching is successful, the search of the LPM matching table is stopped, the forwarding information is obtained by using the destination address stored in the EXACT matching table, and then the received IP packet is converted into the destination address. An EXACT matching processing step of transferring to a; And when the EXACT matching fails, after performing the LPM matching table search, completing the LPM matching check, and obtaining forwarding information using the destination address stored in the LPM matching table. And an LPM matching processing step of forwarding the received IP packet to the destination address and registering an LPM matching result in the EXACT matching table.

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On the other hand, the present invention in the asynchronous transmission mode (ATM) -based routing system, by separating the Internet Protocol (IP) packet from the data frame input through the Ethernet / frame relay network, to search for the destination address for the IP packet, Ethernet / frame relay (FR) input port processing means for dividing the IP packet into ATM cells and transmitting the same to the switching means; An ATM input port processing means for extracting an ATM cell from a data frame input through an ATM network, searching for a destination address of an ATM cell according to the type of the extracted ATM cell, and transmitting the ATM address to the switching means; The switching means for switching the ATM cell transmitted from the Ethernet / frame relay input port processing means and the ATM input port processing means and transferring the same to an output port; Ethernet / frame relay output port processing means for combining and generating an ATM packet by combining the ATM cells transmitted from the switching means, and generating a data frame from the stored IP packet and transmitting the data frame to the destination address; ATM output port processing means for combining the ATM cell transmitted from the switching means to transmit to the destination address through a transmission line frame; And network processing means for distributing the IP packet forwarding by distributing the IP forwarding information table to all input ports of the router.

The present invention is to distribute and process the IP forwarding function in the system, and to distribute the IP packet forwarding by distributing the IP forwarding information table configured in the dedicated network processor performing the routing protocol function to all the input ports of the router. have. In other words, when an IP packet is input from the high-speed router, the forwarding information table is searched by applying the EXACT-matching algorithm and the LPM-matching algorithm at the same time, divided into ATM cells, and delivered to the ATM switch fabric. After recombining the cells to be received from the fabric, IP packets are constructed, stored in a queue for each IP QoS class, and the IP packets are forwarded according to the QoS of the IP packets through a separate IP packet scheduler.
According to the present invention, it is possible to provide a function as a high speed ATM-based IP router while providing the existing ATM switch function as it is.
The above objects, features and advantages will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram of an ATM-LAN backbone network using an ATM-based layer 3 router to which the present invention is applied, and shows the configuration of an ATM-LAN backbone network 101 using an ATM-based router 102.

The ATM-LAN backbone network 101 may be connected to various LAN domains such as the ATM-LAN 103, the Ethernet LAN 104, and the frame relay network 105.

It is a main function of the ATM-based router 102 for the ATM-LAN backbone network 101 to smoothly support the connection of the IP host 106 between the IP domains 103 to 105. In order to provide such a function, the ATM-based router 102 should basically have a routing protocol function and an IP forwarding function of the conventional router.

In the case of the conventional backbone LAN router, since the amount of IP traffic to be handled by a single router was not large, the IP forwarding function could be centralized and processed, but as the IP traffic to be handled by a single backbone router has recently increased rapidly, The centralized IP forwarding method cannot handle IP forwarding properly.

2 is a diagram illustrating an embodiment of an ATM based routing system according to the present invention.
As shown in FIG. 2, the ATM-based routing system according to the present invention separates an IP packet from a data frame input through an Ethernet / frame relay network, searches for a destination address for the IP packet, and retrieves an IP packet. ATM cells extracted from the frame relay (FR) / Ethernet input port processors 202 and 204 for segmenting the ATM cells and transmitting them to the cell-based ATM switch fabric 205 and data frames input through the ATM network. ATM input port processor 203, frame relay / Ethernet input port processor 202, 204, and ATM input port processor 203 for retrieving the destination address of the ATM cell and transmitting to the cell-based ATM switch fabric 205 according to the type Cell-based ATM switch for switching the ATM cell forwarded from Ethernet port) to Ethernet / Frame Relay output port processor (210,211) or ATM output port processor (209). An Ethernet / frame relay output for combining the brick 205 and the ATM cells delivered from the cell-based ATM switch fabric 205 to generate and store IP packets, and to generate data frames from the stored IP packets and transmit them to a destination address. Port outputs (210, 211), ATM output port processor (209) for combining the ATM cells delivered from the cell-based ATM switch fabric 205 to the destination address through the transmission line frame, IP forwarding information table of the router A network processor 201 for distributing IP packet forwarding by distributing to all input ports is included.

Since the routing protocol of the ATM-based router 102 does not need to be processed in real time, it is performed through a separate network processor 201, and the network processor 201 performs a next hop of an IP packet received by the ATM-based router 102. After obtaining a routing information table (RIB) 207 representing Next-Hop information by performing a routing protocol, the frame relay input port processor 202 serving as each line matching device through the IPC path 206. The routing information of the routing information table (RIB) is distributed to the ATM input port processor 203 and the Ethernet input port processor 204.

The routing information table (RIB) 207 transmitted to each input port processor 202 to 204 is a forwarding information base (FIB) in the form of an IP look-up table for performing actual IP forwarding. Stored at 208.

Each input port processor 202-204 of the ATM-based router 102 can use the forwarding information table (FIB) 208 to process the IP packets received at the maximum line speed, so that an efficient IP lookup ( Look-Up) function.

The cell-based ATM switch fabric 205 switches a fixed length cell transmitted from the input port processors 202 to 204 corresponding to the line matching card and transmits the fixed length cell to the output port processors 209 to 211.

3 is a diagram illustrating an embodiment of an Ethernet / frame relay line input / output port processing apparatus according to the present invention.

As shown in FIG. 3, the Ethernet / Frame Relay (FR) input port processing apparatus 301 is an input for separating an IP packet encapsulated in a data frame for each Ethernet or Frame Relay (FR) line. Outputs an IP packet that has completed the processing of the IP header for the next-hop line connection unit 302, an IP route search unit 303 for finding a next-hop of a received IP packet ATM cell partitioning and input queue control unit providing a function of sequentially accessing an IP packet queue 304 for each output port to be stored for each port and a queue for each output port to sequentially divide the ATM port into ATM cells, and then transfer the same to the cell-based switch fabric 306. 305).

The Ethernet / Frame Relay (FR) output port processing unit 307 recombines the ATM packets by recombining the ATM cells transmitted from the cell-based switch fabric 306, and then receives the received IP packets into the quality of service of the IP packets. QoS cell recombination unit 308 that provides a function of storing the IP packet class queue 309 according to the Quality of Service (QoS), an IP packet class queue 309 that stores IP for each IP quality of service (QoS), and IP. The IP packet scheduler 310 provides a function of scheduling the packet class queue 309 and delivering the packet class queue 309 to the output line connection unit 311, and encapsulating the IP packet in a frame of media for each Ethernet or frame relay (FR) line. It consists of an output line connection part 311 which performs a function.

4 is a configuration diagram of an embodiment of an ATM line input / output port processing apparatus according to the present invention.

As shown in FIG. 4, the ATM input port processing apparatus 401 includes an input line connection unit 402 that provides a function of extracting a cell from an ATM transmission line frame and transferring the cell to the ATM cell filtering unit 403. ATM cell filtering unit 403 and ATM cell filtering unit 403, which provide a function of separating a cell requiring IP packet processing and a cell requiring only ATM processing among ATM cells, recombine the cells transmitted from the ATM cell filtering unit 403 to form an IP packet. IP recombination unit 404 that provides the function of recombination, IP path retrieval unit 405 that finds the next hop of the recombined IP packet, and the IP header for the next hop. An ATM cell providing a function of sequentially accessing an IP packet queue 406 for each output port for storing the processed IP packet for each output port, and sequentially dividing the queue for each output port into an ATM cell, and then delivering the packet to the input queue controller 409. The division unit 407 and the ATM cell filtering unit 403 A cell-based switch fabric by alternately accessing the ATM cell queue 408 for each output port and the ATM cell partitioner 407 and the ATM cell queue for each output port alternately providing the function of storing the on-cell for each output port. The input queue control unit 409 provides a function of delivering an ATM cell to the 410.

And, the ATM output port processing unit 411, the output queue control unit 412, which provides a function for storing the ATM cell transmitted from the cell-based switch fabric 410 to the output queue 413 for each ATM connection, for each ATM connection Output line connection unit 415 by scheduling an output queue 413 for each ATM connection and a cell stored in the output queue 413 for each ATM connection according to the quality of service (QoS) for each ATM connection. An ATM cell scheduler 414 provides a function of delivering an ATM cell, and an output line connection unit 415 performing a function of delivering an ATM cell to an ATM transmission line frame.

FIG. 5 is a diagram illustrating the structure of an Ethernet / frame relay input / output port processing protocol stack applied to the present invention, and illustrates a function performed by the Ethernet / frame relay input / output port processors 301 and 307 using the protocol stack.

As shown in FIG. 5, referring to a processing protocol stack 501 of an Ethernet / frame relay input port, a signal received from an Ethernet / FR line may include physical layer processing, data link layer processing, and IP decapsulation function 502. After sequentially passing through the IP packet, the decapsulated IP packet is processed through the IP look-up of the IP forwarding function 503 and the IP header processing for the next hop is completed. After encapsulation via the IP encapsulation function 504 on the ATM, the encapsulated IP packet is transmitted through an ATM Adaptation Layer (AAL) function (hereinafter referred to as "AAL"). After being divided into ATM cells, they are transferred to a cell-based ATM switch fabric 505 through an ATM function.

In addition, referring to the processing protocol stack 506 of the Ethernet / frame relay output port, the ATM cell delivered from the cell-based ATM switch fabric 505 undergoes the ATM layer processing and the AAL layer processing, and then the IP decapsulation function ( The IP packet transmitted to the ATM is extracted through 507, and the extracted IP packet information is processed through the IP interworking function 508 to perform the IP encapsulation function 509 on Ethernet / FR. After the IP encapsulation function 509 is completed, the IP packet undergoes a series of processes transmitted through the Ethernet / Frame Relay (FR) data link layer processing and the physical layer processing to the physical transmission line.

6 is a diagram illustrating a connection protocol stack structure in the ATM / Ethernet / Frame Relay direction according to the present invention, and illustrates a function for performing IP packet routing in the ATM / Ethernet / Relay frame direction using the protocol stack.

As shown in FIG. 6, referring to the processing function stack 601 of the ATM input port, an ATM cell received from an ATM line undergoes a physical layer process, an ATM layer process, and an AAL process, and then an IP decapsulation function. 602, which is configured in the form of an IP packet via an IP decapsulation function 602, and then is transmitted to an IP forwarding function 603.

Then, after the processing of the IP header for the next hop through the IP look-up of the IP forwarding function 603 is completed, the IP encapsulation function to the ATM via the IP encapsulation function (604) The encapsulated, encapsulated IP packet is divided into ATM cells through the AAL function and then transferred to the cell-based ATM switch fabric 605 via the ATM function.

The processing protocol stack 606 of the Ethernet / frame relay output port is the same as the processing protocol stack 506 of the Ethernet / frame relay output port of FIG. 5.

7 is a diagram illustrating a protocol stack structure from the Ethernet / frame relay to the ATM connection direction according to the present invention, and illustrates a function for performing IP packet routing from the Ethernet / frame relay to the ATM direction using the protocol stack.

The processing protocol stack 701 of the Ethernet / frame relay input port is the same as the processing protocol stack 501 of the Ethernet / frame relay input port of FIG.

Referring to the processing protocol stack 703 of the ATM output port, the ATM cell transmitted from the cell-based ATM switch fabric 702 undergoes the ATM layer processing and the physical layer processing functions and then undergoes a series of processes transmitted to the line.

8 is a block diagram of an IP packet forwarding apparatus according to an embodiment of the present invention, and illustrates an IP packet forwarding apparatus performed by each line card of the ATM-based router 102. Referring to FIG.
As shown in FIG. 8, the IP packet forwarding apparatus according to the present invention includes a payload 802, destination header information 803, and encapsulation for an IP packet (receive IP packet) received from the outside. A packet memory 801 that stores information about the encapsulated header 804, IP forwarding information (which may be configured as a separate forwarding information table) 808, and encapsulation header information 804. ), The IP decapsulation unit 805 for separating the data to be delivered to the receiving IP processing unit 806, and the destination header (DH) information 803 is obtained and delivered to the IP forwarder 807. IP forwarding information 808 is retrieved using the destination IP processing unit 806 and the destination header (DH) information 803 transmitted from the reception IP processing unit 806 to obtain IP address information (destination IP address information) for the destination. IP forwarder 807 for locating and forwarding to the transmitting IP processing unit 809, and A transmission IP processing unit 809 for transmitting the IP encapsulation value of the destination IP address information transmitted from the P forwarder 807 to the IP encapsulation unit 810, and the encapsulation header (EH) information 804. ) Is converted into encapsulation header (EH) information that can be processed at the destination, and converts the received IP packet to transmit the converted IP packet to the destination.

The received IP packet is stored in the packet memory 801, wherein the main content of the IP packet stored in the packet memory 801 is an IP packet payload 802, a destination header (DH: Destination address value) of a destination address of the IP packet. Header) (803), and encapsulated header information (EH: Encapsulated Header) 804 attached when the IP is encapsulated.

The IP decapsulation unit 805 analyzes the encapsulation header (EH) 804 value among the stored IP packet information, and then separates and transmits data to be transmitted to the upper receiving IP processing unit 806. to provide.

The receiving IP processing unit 806 obtains a destination header (DH) 803 value among the stored IP packet information and delivers the value to the IP forwarder 807, and the IP forwarder 807 uses the destination header (DH) 803 value. Then, the IP forwarding information table (FIB) 808 is searched for and found in the next hop, and then forwarded to the transmission IP processing unit 809.

The transmitting IP processor 809 transmits an IP encapsulation value for Next-Hop IP address information to the IP encapsulation unit 810, and the IP encapsulation unit 810 transmits a packet memory 801. Replaces the encapsulation header (EH) 804 value of the received IP packet with a new encapsulation header (EH) 804 value for proper processing in the next hop. .

The IP packet having completed the forwarding process for the IP header is forwarded to the next hop.

As shown in the figure, the received IP packet is processed without being copied separately from the packet memory 801, so that IP packet forwarding can be processed at high speed.

9 is a block diagram of an IP packet forwarding function applied to the present invention, and shows an IP packet forwarding processing function in each line card of the ATM-based router 102. Referring to FIG.

The payload 901 and the destination header (DH) 902 of the received IP packet are transferred to the payload 903 and the destination header (DH) 904 of the transmitting IP packet without change.

The IP forwarder 905 simultaneously transfers the destination header (DH) 902 value, which is the destination address of the received IP packet, to the EXACT matching algorithm processing block 906 and the LPM matching algorithm processing block 910. To pass.

The EXACT matching algorithm processing block 906 determines whether an entry equal to the destination header (DH) 902 value of the received IP packet is registered among the EXACT matching IP lookup table 907 entries. .

If an entry equal to the destination header (DH) 902 value of the received IP packet is registered in the EXACT matching IP lookup table 907, the EXACT matching IP lookup table 907 The entry outputs an IP address of the IP forwarding information table 908, which stores encapsulation information for forwarding the received IP packet. In practice, a commercial CAM may be used to perform the above process.

The LPM matching algorithm processing block 910 registers an entry matching the maximum length with a destination header (DH) value 902 of the received IP packet among the LPM matching IP lookup table 911 entries. IP address of the IP forwarding information table 908, which stores the encapsulation information for forwarding the received IP packet. Print the address.

When the EXACT matching algorithm 906 is successfully executed, the IP forwarding information table 908 includes an IP forwarding information table corresponding to an address address input from the EXACT matching IP lookup table 907. The IP forwarding information 909 in 908 is transmitted to the IP forwarder 905, and when the EXACT matching algorithm 906 fails, an address input from the LPM matching IP lookup table 911. The IP forwarding information 909 in the IP forwarding information table 908 corresponding to the address is transmitted to the IP forwarder 905.

The IP forwarder 905 uses the IP forwarding information 909 delivered from the IP forwarding information table 908 to construct and deliver an encapsulation header value 913 for encapsulating an IP packet. In addition, the IP forwarder 905 is a result of the LPM matching algorithm 910 in the EXACT matching IP lookup table 907 when the EXACT matching algorithm 906 fails. By registering the address of the IP forwarding information table 908 and the DH value 902 of the received IP packet in the EXACT matching IP lookup table 907, the EXACT for received IP packets continuously delivered. The IP packet is forwarded at high speed through a matching algorithm 906.

FIG. 10 is a flowchart illustrating a method of forwarding a high-speed internet protocol packet forwarding for an asynchronous transmission mode based switching system according to the present invention, and illustrates a series of processes of forwarding a received IP packet.

First, when an IP packet is received, an IP packet path search is started (1001), and a header value (ie, a destination destination header value) of a received IP packet is first obtained (1002), and then an EXACT is performed. The matching table search operation and the LPM search table search are simultaneously started (1003, 1004) to confirm whether the EXACT matching is performed successfully (1005).

As a result of the verification, if the EXACT matching is successfully performed, the forwarding information is obtained from the forwarding table using the EXACT matching table output address (1006), and then the IP packet is moved to the next hop. Encapsulate and deliver (1007).

As a result of the verification, if the EXACT match fails, the LPM matching table search is continued (if the EXACT match is successfully performed during the search operation, the search is stopped) (1004) (LPM) Checks whether the match search operation completed without interruption (1008).

As a result of the check, if the LPM matching search is successfully completed, the forwarding information is obtained from the forwarding table using the LPM matching table output address (1009), and then the IP is next-hop. Encapsulates and forwards the packet (1007), and simultaneously registers the LPM (LPM) matching result in the EXACT matching search table (1010).

As a result of the check, if the LPM matching search is not completed, the process returns to step 1004 again to continuously perform the LPM matching search.

After performing all the above steps, the IP packet forwarding operation is terminated.
The method of the present invention as described above may be implemented as a program and stored in a computer-readable recording medium (CD-ROM, RAM, ROM, floppy disk, hard disk, magneto-optical disk, etc.).

The present invention described above is capable of various substitutions, modifications, and changes without departing from the technical spirit of the present invention for those skilled in the art to which the present invention pertains. It is not limited by the drawings.

As described above, the present invention uses an ATM cell switching fabric of fixed length, and efficiently distributes the IP forwarding function to all the line cards, and then performs the EXACT-matching in performing the IP forwarding function in each line card. By applying the algorithm and the LPM-matching algorithm simultaneously to process the IP packet at high speed, there is an effect that can reduce the traffic bottleneck and improve the switching performance.

In addition, the present invention has the effect that it can provide a function as a high-speed ATM-based IP router while providing the ATM switch function which is the original function of conventional ATM equipment.

Claims (9)

An internet protocol (IP) packet forwarding apparatus for an asynchronous transmission mode (ATM) based routing system, Storage means for storing payload, destination header information, encapsulation header information, and IP forwarding information for an IP packet (receive IP packet) received from the outside; IP decapsulation means for analyzing the encapsulation header information to separate data to be delivered to a receiving IP processing means; Receiving IP processing means for taking the destination header (DH) information and delivering it to IP forwarding means; The IP forwarding means for retrieving the IP forwarding information by using the destination header (DH) information transmitted from the receiving IP processing means to find IP address information (destination IP address information) for a destination and transmitting the same to the transmitting IP processing means. ; The transmission IP processing means for delivering an IP encapsulation value for the destination IP address information transmitted from the IP forwarding means to IP encapsulation means; And Converting the encapsulation header (EH) information into encapsulation header (EH) information that can be processed at the destination, converting the received IP packet, and transmitting the converted IP packet to the destination. Way High speed internet protocol packet forwarding device for asynchronous transmission mode based switching system comprising a. The method of claim 1, At the IP packet forwarding, In the process of obtaining an encapsulation header using the destination address of the IP packet, the high speed Internet protocol packet forwarding apparatus for the asynchronous transmission mode based switching system, characterized in that the payload information of the IP packet is processed without being copied separately. . An IP packet forwarding method applied to an internet protocol (IP) packet forwarding apparatus for an asynchronous transmission mode (ATM) based switching system, Confirming whether the EXACT matching is successful by searching the EXACT matching table and the Longest Prefix Matching (LPM) matching table using the destination header DH of the IP packet received from the outside; As a result of the checking in the confirming step, if the EXACT matching is successful, the search of the LPM matching table is stopped, the forwarding information is obtained by using the destination address stored in the EXACT matching table, and then the received IP packet is converted into the destination address. An EXACT matching processing step of transferring to a; And As a result of the checking in the checking step, if the EXACT matching fails, the LPM matching table search is continued to complete the LPM matching check, and after the forwarding information is obtained using the destination address stored in the LPM matching table, An LPM matching processing step of forwarding the received IP packet to the destination address and registering an LPM matching result in the EXACT matching table; High speed internet protocol packet forwarding method for asynchronous transmission mode based switching system comprising a. The method of claim 3, wherein The LPM matching processing step, Checking whether the LPM matching is completed by continuously searching the LPM matching table according to the failure of the EXACT matching; And As a result of the checking of the checking step, when the LPM matching is completed, after forwarding information is obtained using the destination address for the received IP packet stored in the LPM matching table, the received IP packet is encapsulated and the Forwarding to a destination address and registering an LPM matching result in the EXACT matching table High speed internet protocol packet forwarding method for asynchronous transmission mode based switching system comprising a. In the asynchronous transmission mode (ATM) based routing system, Ethernet / Frame Relay for separating the Internet Protocol (IP) packet from the data frame input through the Ethernet / Frame Relay network, searching for the destination address for the IP packet, dividing the IP packet into ATM cells, and transmitting the packet to the switching means. FR) input port processing means; An ATM input port processing means for extracting an ATM cell from a data frame input through an ATM network, searching for a destination address of an ATM cell according to the type of the extracted ATM cell, and transmitting the ATM address to the switching means; The switching means for switching the ATM cell transmitted from the Ethernet / frame relay input port processing means and the ATM input port processing means and transferring the same to an output port; Ethernet / frame relay output port processing means for combining and generating an ATM packet by combining the ATM cells transmitted from the switching means, and generating a data frame from the stored IP packet and transmitting the data frame to the destination address; ATM output port processing means for combining the ATM cell transmitted from the switching means to transmit to the destination address through a transmission line frame; And Network processing means for distributing IP packet forwarding by distributing IP forwarding information table to all input ports of router Routing system comprising a. The method of claim 5, wherein The Ethernet / frame relay (FR) input port processing means, First input line connecting means for separating an IP packet from a data frame input through an Ethernet / frame relay network; First IP path searching means for searching for a destination address of the separated IP packet; An IP packet storage means for each first output port for storing the IP packet for each output port using the destination address; And  ATM cell division and control means for sequentially accessing the IP packet storage means for each of the first output ports, dividing the IP packet into ATM cells, and delivering the IP packet to the switching means. Routing system comprising a. The method of claim 5, wherein The ATM input port processing means, Second input line connection means for extracting an ATM cell from a data frame input through the ATM network and transferring the extracted ATM cell to an ATM cell filtering means; The ATM cell filtering means for separating a cell requiring IP packet processing and a cell requiring ATM processing from the extracted ATM cells; IP packet recombination means for recombining the ATM cells delivered from the ATM cell filtering means into recombination into IP packets; Second IP path searching means for searching for a destination address of the recombined IP packet; IP packet storage means for each second output port for storing the IP packet for each output port by using the retrieved destination address; ATM cell dividing means for sequentially accessing the IP packet storing means for each second output port, dividing the stored IP packet into ATM cells, and transmitting the divided IP packets to the input control means; ATM cell storage means for each output port for storing the ATM cells transmitted from the ATM cell filtering means for each output port; And The input control means for alternately accessing the ATM cell dividing means and the ATM cell storing means for each output port to transfer the ATM cell to the switching means; Routing system comprising a. The method according to any one of claims 5 to 7, The Ethernet / frame relay output port processing means, ATM cell recombination means for combining the ATM cells delivered from the switching means to regenerate an IP packet; IP packet class storage means for storing the regenerated IP packet according to the quality of service (QoS); IP packet scheduling means for scheduling the stored IP packet to deliver it to the first output line connection means; And Means for connecting the first output line to generate a frame from a scheduled IP packet and transmit the frame to the Ethernet / frame relay network Routing system comprising a. The method of claim 8, The ATM output port processing means, Output control means for transferring the ATM cell coming from the switching means to output storage means for each ATM connection; Output storage means for each ATM connection for storing the ATM cell according to an ATM connection quality of service (QoS); ATM cell scheduling means for scheduling the stored ATM cell according to the quality of service (QoS) for each ATM connection and transferring the stored ATM cell to the second output line connection means; And A second output line connecting means for generating a frame from a scheduled ATM cell and transmitting the frame to the ATM network Routing system comprising a.

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