JP3671360B2 - Packet router processor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a protocol processing related to route information in a communication system and a packet router processing device (hereinafter referred to as “router processing device”) that performs a data packet transfer process based on the route information.
[0002]
[Prior art]
Generally, in a router processing device, roughly divided,
(1) Protocol processing related to route information
(2) Data packet transfer processing is performed.
In the conventional router processing apparatus, the protocol processing relating to the route information (1) is performed as follows.
(a) A path information packet is received via a communication line from a partner host that exchanges path information in the line corresponding unit.
(b) Perform protocol processing related to route information.
Conventionally, BGP, OSPF, RIP, or the like has been used as a protocol for route information. References: Nishida, TCP / IP internetworking (ISBN4-915778-23-1), etc.
(c) The protocol processing result is reflected in the path information storage table.
[0003]
In the conventional router processing apparatus, the data packet transfer process (2) is performed as follows.
(d) The data corresponding unit receives the data packet on the communication line and extracts the header portion of the data packet. In the header part, a destination address and a transmission source address are stored.
(e) A search process is performed from the path information storage table using the destination as a key, information such as a gateway address stored in the entry is obtained, and a transmission destination of the data packet is determined.
(f) A conversion process from the destination address to the link layer address is performed. If there is no link layer address on the route information storage table, the link layer address is obtained using ARP (Address Resolution Protocol) or the like. Reference: Above.
(g) A data packet is transmitted with the destination link layer address obtained above as a destination.
[0004]
[Problems to be solved by the invention]
A conventional router processing apparatus has a configuration as shown in FIG. In FIG. 7, 1 is a protocol processing unit, 2 to 5 are line correspondence units, and 11 to 14 are communication lines in units of 2 to 5 units. Here, it is assumed that the protocol processing unit 1 and the line corresponding units 2 to 5 are connected on the same bus and transfer each other. In this router processing apparatus, in order to determine a transfer destination of a data packet in each line corresponding unit, in order to perform a search process using a route information storage table managed in a centralized manner in the protocol processing unit 1, There were the following problems.
[0005]
(1) Processing related to data packet transfer control is delayed until the search processing is completed.
(2) When processing search requests from a plurality of line corresponding units at the same time, it takes CPU time to search for a specific line corresponding unit, and other search processes may be delayed irregularly. In particular, this problem becomes conspicuous when a plurality of connected lines become high speed like FDDI and B-ISDN.
(3) Every time a search request is input to the part that performs the search processing of route information, an interrupt is generated, CPU time is taken for the interrupt processing, and the real-time property of the entire system is lowered. When a plurality of connected lines become high-speed like FDDI, B-ISDN, one packet interval is shortened, which becomes particularly remarkable.
[0006]
In addition, there is an example in which search results are placed in a cache table held by each line correspondence unit so that frequent search processing requests do not occur, but this also has the following problems.
(4) The contents of the cache table and the latest route information managed by the protocol processing unit are inconsistent and it is necessary to frequently skip special messages in order to match. This message transmission / reception increases as the number of line-corresponding units increases, which makes management by the protocol processing unit difficult and increases the CPU usage rate of the protocol processing unit.
[0007]
In addition, the following problems also occur in the line correspondence section on the output side.
(5) In the line corresponding unit on the output side, a process for converting the destination address into a link layer address and a process for acquiring the link layer address are required. Therefore, CPU time is taken for the conversion process. In addition, for this processing, since data packets are accumulated and transferred to the output line correspondence unit, a delay occurs and a large amount of buffers are required.
[0008]
Furthermore, in the configuration example of the same bus connection as shown in FIG.
(6) When multiple line compatible units perform transfer processing simultaneously, due to bus contention,
Only one transfer process is performed and the other transfer processes are blocked.
FIG. 8 shows an operation example in the method (1). In FIG. 8, the vertical direction indicates the passage of time, and each vertical line indicates the elapsed operation time in each part. Hereinafter, an operation in the case where data packets are continuously input to the line corresponding unit 2 will be described.
[0009]
In the first data packet transfer process, the data packet {circle over (1)} is input from the communication line to the line corresponding unit 2 and a search request for the corresponding destination is issued to the protocol processing unit 1 based on the header information. Is done.
The search processing unit of the protocol processing unit 1 searches the path information table to which line corresponding unit the corresponding destination is to be transferred. The search result is transferred as a search response to the line corresponding unit that issued the search request.
The line corresponding unit 2 that has received the result that the search result is the line corresponding unit 3 transfers the corresponding data packet to the output side line corresponding unit 3 via the bus.
[0010]
The output line correspondence unit 3 searches the table for the link layer address of the received data packet. Here, if it is not on the table, the broadcast packet is transmitted on the line using ARP (Address Resolution Protocol) or the like, and the returned reply packet is analyzed to obtain the link layer address. . When the link layer address is determined, the data packet is output on the line with the address as the destination.
Thereafter, similarly, the second data packet is processed.
[0011]
As described above, the conventional router processing device cannot transfer to the output-side line correspondence unit unless the route information search result from the protocol processing unit is obtained in the input-side line correspondence unit, A process for converting to a link layer address is required, and it is difficult to obtain a high data packet transfer processing speed.
FIG. 9 shows a case where data packets are input simultaneously to the two line corresponding units 2 and 4. The line corresponding units 2 and 4 extract the destination field of the input data packet and issue a search request to the protocol processing unit, respectively.
[0012]
At this time, if the search request (1) issued from the line correspondence unit 2 arrives a little earlier, the search process (1) is performed first, and the search response (1) is returned to the line correspondence unit 2. Since the search request (2) is accepted, the search response (2) of the line corresponding unit 4 is delayed as a result.
The line corresponding unit 2 receives the search response {circle around (1)} and performs transfer processing to the line corresponding unit 3, and the line corresponding unit 3 performs destination link layer address conversion and line output processing. The line corresponding unit 4 receives the search response {circle around (2)} and performs transfer processing to the line corresponding unit 5, and the line corresponding unit 5 performs conversion of the destination link layer address and output processing to the line.
[0013]
As described above, in the conventional router processing apparatus, when a search request from a plurality of line corresponding units is processed at the same time, the search process of a specific line corresponding unit delays other search processes, so that the throughput of the entire system is reduced. There was a problem of not going up.
The present invention has been made in view of the above circumstances. The object of the present invention is to solve the above-mentioned problems in the prior art, increase the number of accommodated lines, increase the capacity of transfer lines, and change the route information exchange destination. It is an object of the present invention to provide a router processing apparatus that does not affect the transfer processing capability of individual data packets even if the increase is made.
[0014]
[Means for Solving the Problems]
The above-described object of the present invention is to receive a data packet on a communication line, send a data packet on the communication line, a plurality of line corresponding units, and a plurality of protocol processing units to process protocol data related to route information. A router processing unit that couples the units to each other and performs transfer processing based on a link layer address, and the protocol processing unit receives protocol data at the input side of the line corresponding unit. Message transfer having a conversion table for associating external address information obtained from the result of processing with link layer address information used in the switch unit, and exchanging messages between the units Means and data transfer means for transferring data packets between the line corresponding parts, each line corresponding part Independently, the destination information of the external address of the data packet input from the communication line is converted into the link layer address information of the destination using the conversion table, and directly transferred via the switch unit Achieved by a router processor.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
In the router processing apparatus according to the present invention, the processing related to the routing information control and data packet transfer control of the router processing apparatus is realized as follows.
First, the protocol processing related to route information shares functions with the following units.
(1) Line correspondence part: Accesses the communication line and sends / receives data to / from other router processing devices.
(2) Protocol processing unit: Performs protocol processing related to route information
(3) Line correspondence unit: Reflects the latest route information obtained in the conversion table in each line correspondence unit.
In the above-described protocol processing of route information, after the route information packet is received by the line corresponding unit, the information is transferred to the protocol processing unit using the message transfer means, and the protocol processing of the route information is executed there. The update data of the route information obtained as a result is sent to the corresponding line corresponding unit using the message transfer means, and each line corresponding unit transmits the obtained route information and the link layer address information used in the switch unit. A conversion table for associating is generated.
[0017]
Further, the apparatus according to claim 2 is configured such that a destination address including a host address, a source address including a host address, application type information, protocol information used, or a combination thereof can be specified as an index of the conversion table. ing. The apparatus according to claim 3 is configured so that output permission / prohibition can be output as the conversion value of the conversion table.
[0018]
After generating these conversion tables, the processing related to data packet transfer control shares the functions of the following units.
(1) Line corresponding part connected to communication line
(2) Conversion table provided on the input side of the line interface to convert route information and link layer address
(3) Switch part [0019]
After receiving the data packet, the line corresponding unit extracts the destination address in the header portion, and refers to the conversion table in order to convert the destination address into a link layer address corresponding to the destination device. When the link layer address of the destination is determined, the data packet is transferred to the switch unit using the data transfer means. The switch unit transmits a data packet to a device having a destination link layer address.
The apparatus according to claim 3 performs transfer when the conversion result is output permission, and does not perform transfer when the output is prohibited.
[0020]
Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings.
FIG. 1 is a configuration diagram of a router processing apparatus according to an embodiment of the present invention. Here, a case where there are two protocol processing units and four line corresponding units will be described as an example.
In the figure, 1 is a protocol processing unit, 2 to 5 are line corresponding units, and 11 to 14 are communication lines in units of 2 to 5 units. Reference numeral 6 denotes a switch unit capable of link layer switching, and reference numerals 7 to 10 denote conversion tables provided in the line corresponding units 2 to 5. The conversion tables 7 to 10 can be configured using a normal memory or the like.
[0021]
The above-described switch unit 6 can be configured by an Ethernet switch, FDDI switch, ATM switch, HIPPI switch, Fiber channel switch, or the like.
It is possible to transfer messages between the modules of the protocol processing unit 1 and the line corresponding units 2 to 5, and between the line corresponding units 2 to 5 it is possible to transfer data that exchanges data packets. is there. Each module of the protocol processing unit 1 and the line corresponding units 2 to 5 can be realized by a general-purpose workstation, a personal computer (personal computer), etc., each of which includes a switch unit interface in the processor.
[0022]
Note that as the above-described communication lines 11 to 14, communication lines such as FDDI, Ether, ATM, HIPPI, and Fiber channel are used.
The means for transferring the message described above can be realized by using a normal message passing mechanism between multiprocessors, and the data transfer means can use means such as DMA transfer.
Next, actual path information control and data transfer control methods will be described with reference to FIG.
[0023]
It is assumed that the external address used in FIG. 2 has a 32-bit address system compliant with IP (Internet Protocol). The notation of / 16 used below indicates the bit length of the netmask, and if it is / 16, the network portion indicates 16 bits. This has the same meaning as the netmask 255.255.0.0.
In the configuration of FIG. 2, the IP address of the host device 15 is 10.0.0.5/24, and the IP address of the host device 16 is 10.0.1.6/24.
[0024]
An IP address is also assigned to each line corresponding unit. The line corresponding unit 2 has the address 10.0.0.1/24, the line corresponding unit 3 has the address 10.0.1.1/24, the line corresponding unit 4 has the address 10.0.2.1/24, and the line corresponding unit 5 has the address 10.0.3.1/24.
In FIG. 2, reference numerals 17 and 18 denote external router devices (route information exchange nodes) connected to the outside. The IP address of the side connected to the communication line 13 of the external router device 17 is 10.0.2.2/24, the host 19 The side connected to the communication line 14 of the external router device 18 is 10.0.3.3/24, and the side connected to the host 20 is 192.186.1.11/24.
[0025]
In FIG. 2, 19 and 20 are hosts connected to the ends of the external router devices 17 and 18, respectively. The IP addresses of the hosts are 172.167.7.8/16 and the host 20 is 192.168.1.3/24.
Each of the devices connected to the switch unit 6 is given a link layer address. The line correspondence unit 2 has an address 200, the host device 15 has an address 201, the line correspondence unit 3 has an address 300, and the host device 16 has an address 301. The line correspondence unit 4 has an address 400, the external router device 17 has an address 401, the line correspondence unit 5 has an address 500, the external router device 18 has an address 501, and the protocol processing unit has an address 999.
[0026]
First, a route information control method will be described with reference to FIG. Here, a method in which the router processing apparatus according to the present embodiment exchanges route information with the external router apparatuses 17 and 18 will be described. Protocol processing of the route information is performed by the protocol processing unit 1, and the route information from the external router devices 17 and 18 is received by the line corresponding units 4 and 5 through the communication lines 13 and 14, and the information is transmitted to the message transfer means. Is transferred to the protocol processing unit 1 via the switch unit 6. The protocol processing unit 1 performs route information protocol processing such as BGP and OSPF. The protocol processing unit 1 can reduce the load by arranging a plurality of units in parallel.
[0027]
FIG. 3 shows an example of route information managed by the protocol processing unit 1 of the router processing apparatus shown in the present embodiment, obtained as a result of the above-described operation. In the example shown here, network addresses, netmasks, gateway addresses (relay addresses), attributes, etc. are managed. The route information of 172.16.0.0/16 is transferred from the external router device 17 to the protocol processing unit 1, and the route information of 192.168.1.0/24 is transferred from the external router device 18 to the protocol processing unit 1, as shown in the table of FIG. It is reflected in.
In FIG. 3, as a network connected to the router processing apparatus shown in this embodiment, 10.0.0.0/24 connected to the line corresponding unit 2, 10.0.1.0/24 connected to the line corresponding unit 3, and the line corresponding unit. The information of 10.0.2.0/24 connected to 4 and 10.0.3.0/24 connected to the line corresponding unit 5 is described on the table.
[0028]
As a result of the above processing, when the update of the route information is confirmed, the protocol processing unit 1 in FIG. 2 transmits the update data to each of the line corresponding units 2 to 5 via the switch unit 6 using the message transfer means. . The line corresponding unit that has received the update data performs reproduction processing such as addition / deletion of entries in the conversion tables 7-10.
FIG. 4 shows an example of a conversion table configured based on route information data. As shown in FIG. 4, it is composed of a destination network address, a destination netmask, a gateway address (outgoing relay address), and a destination link layer address. When there is no netmask, it indicates an address that needs to be compared with all IP addresses of 32 bits.
[0029]
Next, the operation of data packet transfer control using the conversion table generated in this way will be described with reference to FIG. In FIG. 2, a case where transfer from the host device 15 to the host device 16 is performed will be described.
The data packet with the destination 10.0.1.6 sent from the host device 15 is input to the line corresponding unit 2 via the line 11. In the line corresponding unit 2, the destination 10.0.1.6 is designated as an index using the conversion table shown in FIG. As can be seen from FIG. 4, the destination 10.0.1.6 is a target for comparison of all 32 bits, and can be converted to the link layer address 301.
[0030]
The line corresponding unit 2 designates an address 301 and sends a data packet to the switch unit 6. As a result, the data packet is output to the line 12 via the line corresponding unit 3. Since the host device 16 connected on the line 12 is a data packet having its own link layer address, it receives it. In this way, a series of data packet transfer processes can be executed.
Further, FIG. 2 shows a case where transfer is performed from the host 19 connected to the external router to the host 20.
[0031]
The data packet sent from the host 19 and destined for 192.168.1.3 is forwarded by the external router device 17 and input to the line correspondence unit 4 of the router processing device via the communication line 13. The line corresponding unit 4 designates the destination 192.168.1.3 as an index using the conversion table 9 shown in FIG.
In this case, by applying the network mask written in the conversion table 9, it is extracted which part of the 32 bits is the network part on the table. As a result, since the mask of the entry portion of 192.168.1.0 is 255.255.255.0, when this mask is applied to 192.168.1.3, 192.168.1.0 is obtained, indicating that it matches this entry.
[0032]
From the entry, the gateway address is 10.0.3.3, and the link layer address 501 can be extracted as the conversion value. The line corresponding unit 4 designates the above-described address 501 and transmits a data packet to the switch unit 6. As a result, the data packet is output to the line 14 via the line corresponding unit 5. The external router device 18 connected to the line 14 receives the data from the above-mentioned packet, which is a data packet having the address of the link layer addressed to the external router device 18, receives it, analyzes the destination address, and sends it to the host 20. Forward. In this way, a series of data packet transfer processes can be executed.
[0033]
FIG. 5 shows an operation example in the present embodiment. In FIG. 5, as in FIG. 8, the vertical direction indicates the passage of time, and each vertical line indicates the operation elapsed time in each part. The operation when data packets are continuously transferred from the host device 15 to the host device 16 will be described below.
First, it is assumed that route information control is performed in advance in the protocol processing unit 1, and the conversion table 7 of the line corresponding unit 2 is initialized and generated based on the result.
[0034]
In the transfer processing of the first data packet, the data packet {circle around (1)} is input from the host device 15 to the line corresponding unit 2, and the destination IP address of the header information is used as an index, and the link layer of the host device 16 is converted by the conversion table. Convert to address. A data packet is directly transferred via the switch unit 6 to the host device 16 having the link layer address via the line corresponding unit 3.
[0035]
The transfer processing of the second data packet is performed in the same manner. However, since the transmission destination can be determined independently within the line corresponding unit 2, continuous operation is possible in a pipeline manner.
Since the data packet transfer process (1) from the line corresponding unit 2 to the host device 16 is performed by DMA, it can be performed in parallel with the data packet input process (2).
[0036]
Next, the parallel operation example in a present Example is shown using FIG. 6, as in FIGS. 5 and 8, the vertical direction indicates the passage of time, and each vertical line indicates the operation elapsed time in each part. Hereinafter, an operation when data packets are continuously transferred from the host device 15 to the host device 16 and when data packets are simultaneously transferred from the host 19 to the host 20 will be described.
Here, as in the example shown in FIG. 5, the routing information control is performed in advance in the protocol processing unit 1, and the conversion table 7 of the line corresponding unit 2 is initialized and generated based on the result. It shall be.
[0037]
The parallel operation in the present embodiment shows a case where data packet inputs are simultaneously made to the two line corresponding units 2 and 4. In the line corresponding units 2 and 4, the destination field of the input data packet is extracted, and at the same time, the link layer address to be output is determined by the conversion table. As a result, the line corresponding unit 2 performs the transfer process (1) for the host device 16, and the line corresponding unit 4 performs the transfer process (2) for the external router device 18. These two transfer processes can be transferred simultaneously by the mechanism of the switch unit 6 having a non-block configuration.
[0038]
In this way, output processing from a plurality of line corresponding units can be performed in parallel, so that the throughput of the entire system can be increased.
In addition, since the conversion table according to claim 2 is configured to be able to convert the transmission source address, the protocol type, and the like as an index in addition to the destination information shown in FIG. 4, finer conversion control is possible. Furthermore, in the conversion table according to claim 2, in addition to the port address of the line corresponding unit, the output permission / prohibition can be extracted as the conversion value as the conversion value.
In addition, each said Example showed an example of this invention, and it cannot be overemphasized that this invention should not be limited to these.
[0039]
【The invention's effect】
As described above in detail, according to the present invention, an increase in the number of accommodated lines, an increase in transfer line capacity, and an increase in the number of routing information exchange destinations do not affect the transfer processing capability of individual data packets. There is a remarkable effect that it is possible to realize a router processing device that is not present.
More specifically, it is possible to solve all the problems described in the section of the problem to be solved by the invention and to realize a router processing apparatus that is very effective in practice.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a router processing apparatus according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating a route information control method and a data transfer control method in the router processing apparatus according to the embodiment.
FIG. 3 is a diagram illustrating route information managed by a protocol processing unit in the router processing apparatus according to the embodiment.
FIG. 4 is a diagram illustrating the configuration of a conversion table in the router processing apparatus according to the embodiment.
FIG. 5 is a diagram (part 1) for explaining the operation of the router processing apparatus according to the embodiment;
FIG. 6 is a diagram (part 2) for explaining the operation of the router processing apparatus according to the embodiment.
FIG. 7 is a configuration diagram of a conventional router processing apparatus.
FIG. 8 is a diagram (part 1) for explaining the operation of a conventional router processing apparatus;
FIG. 9 is a diagram (part 2) for explaining the operation of the conventional router processing apparatus;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Protocol processing part 2-5 Line corresponding part 6 Switch part 7-10 Conversion table 11-14 Communication line 15,16,19,20 Host apparatus 17,18 External router apparatus

Claims (3)

A plurality of line corresponding units that receive data packets on a communication line and send data packets on the communication line, a plurality of protocol processing units that process protocol data related to route information, and the above units are coupled to each other. A packet router processing apparatus having a switch unit that performs transfer processing based on a link layer address, and obtained on the input side of the line corresponding unit from the result of processing of protocol data in the protocol processing unit. A transfer table that associates the received external address information with the link layer address information used in the switch unit, and exchanges messages between the units, and the line correspondence unit Data transfer means for transmitting and receiving data packets between each other, and each of the line corresponding units communicates independently. The destination information of the external address of the data packet inputted from the line, using the conversion table converts the link layer address information of the destination, with transfers directly via the switch unit, wherein the conversion table, the conversion A packet router processing apparatus configured to be able to designate a destination address including a host address, a source address including a host address, application type information, information on a used protocol, or a combination thereof as an index . A plurality of line corresponding units that receive data packets on a communication line and send data packets on the communication line, a plurality of protocol processing units that process protocol data related to route information, and the above units are coupled to each other. A packet router processing apparatus having a switch unit that performs transfer processing based on a link layer address, and obtained on the input side of the line corresponding unit from the result of processing of protocol data in the protocol processing unit. A transfer table that associates the received external address information with the link layer address information used in the switch unit, and exchanges messages between the units, and the line correspondence unit Data transfer means for transmitting and receiving data packets between each other, and each of the line corresponding units communicates independently. The destination information of the external address of the data packet input from the line is converted into the link layer address information of the destination using the conversion table, and is directly transferred via the switch unit. A packet router processing apparatus , characterized in that output permission / prohibition can be output as a value . A plurality of line corresponding units that receive data packets on a communication line and send data packets on the communication line, a plurality of protocol processing units that process protocol data related to route information, and the above units are coupled to each other. A packet router processing apparatus having a switch unit that performs transfer processing based on a link layer address, and obtained on the input side of the line corresponding unit from the result of processing of protocol data in the protocol processing unit. A transfer table that associates the received external address information with the link layer address information used in the switch unit, and exchanges messages between the units, and the line correspondence unit Data transfer means for transmitting and receiving data packets between each other, and each of the line corresponding units communicates independently. The destination information of the external address of the data packet input from the line is converted into the link layer address information of the destination using the conversion table, and is directly transferred via the switch unit. As an index, it is possible to specify a destination address including a host address, a source address including a host address, application type information, information of a protocol used, or a combination thereof, and output permission / prohibition can be output as a converted value. A packet router processing apparatus characterized by the above.

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