JP2000151701A - Inter-network connecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inter-network connecting device which is capable of confirming and verifying a routing function and performance without adding special hardware logic or connecting another equipment. SOLUTION: A function of TTL specification defined in a protocol in a computer network system is used and a load is added by packet folding back inside a router. By setting a TTL value in an IP header to two or more, hardware performs interruption with a processor after the hardware performs packet folding back for the number of times of TTL value. Thus, a load is added upon a routing control part and transfer function diagnostic test of the routing function is executed by a single inter-network connecting device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inter-network connecting device provided in a computer network system, and more particularly to a method for verifying a transfer function of routing performed at high speed in the inter-network connecting device.

[0002]

2. Description of the Related Art A method for verifying a routing function of an inter-network connecting apparatus is based on execution of a test program by a program execution unit in the apparatus or input of a signal from an external apparatus.

FIG. 1 shows a flow of packet transfer of a verification program executed by an internal processor of a router. C in FIG.
PU is a processor inside the router, PB is a packet buffer control unit, RCTL is a routing control unit, and NIF is a line control unit. The verification program converts the packet sent to RCTL to C to verify the routing function.
Set the routing information to be transmitted to the PU. Also, N
Information is set to the IF so that the packet from the PB is internally looped back. Then, a packet is created in PB, and P
Execute the transmission command for B.

[0004] The PB sends a packet to the NIF. NI
F returns to PB internally without sending the packet out of the device
Send to The PB determines the destination by RCTL from the packet header and returns the packet to the processor unit. The program compares and confirms the content of the returned packet data with the content of the transmitted packet data.

FIG. 2 shows a verification configuration by the packet generator. R1 is a router to be verified, and A1 is a line analyzer. Create a packet in A1, and from NIF to R1
Send the packet to The NIF transmits the packet to the PB and determines the destination by RCTL from the header of the packet.
The PB returns to the NIF as indicated and returns the packet to A1. A1 confirms the received packet.

The packet processing function and the contents of packet data are verified using these methods.

[0007]

At present, it is possible to mount logic on hardware with high density by improving the manufacturing technology of LSI and the like. For this reason, it is possible to implement logic at a high density, execute a packet processing function only by hardware, and perform packet processing at high speed without relying on a program. As a result, a device with a high packet processing capability that greatly exceeds the program processing capability is created. Is gone. It is necessary to use an external device in order to perform a functional test that applies a load for verifying the processing capability. However, if the internal packet processing capability is higher than the external packet transfer capability, no load is applied to the inside, and the transfer processing capability cannot be verified. As the processing power on the function verification side has increased in this way,
There is no load on the function verification side due to the processing capability of the processor and the capability of the external device, and the processing capability cannot be verified.

An object of the present invention is to provide a routing function without adding special hardware logic or connecting another device.
An object of the present invention is to provide an inter-network connection device capable of confirming and verifying performance.

[0009]

In order to achieve the above-mentioned object, an inter-network connecting apparatus according to the present invention executes a function of transmitting and receiving network data, a memory function of buffering the data, and a routing control based on the data. Means for detecting a specific field of the network data when the network data is received and buffered in the memory, and Means for interrupting the processor when the field value detected by the detecting means is a specific value; means for comparing the buffered network data with any data set by the processor; and executing the routing control Buffered by hardware Tsu network detects the destination based on the address field of the data comprises means for transferring the network data, and means for subtracting the data of a specific field of the network data in the hardware.

[0010] The detecting means may be an IPv4 (Intern)
et Protocol version 4) TTL (Time t) in the IP header of the network packet
oLive) field and causes an interrupt to the processor when the TTL goes to zero.

[0011] Further, the network connecting apparatus is provided with the T
Buffer network data when TL becomes 0.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 3 shows a header format of a packet in the IPv4 system. Information such as the version of packet data is set in the packet management information shown in FIG. The TTL sets the number of times the router can pass. Addresses such as a source and a destination are set in the address information. Each time the network connecting device passes through the router once, the TTL
The value is decremented by one.

The network connection apparatus normally discards the packet data automatically when the TTL of the packet data becomes zero. This function is defined by a protocol, and prevents a transmitted packet from continuing to travel around the network forever due to defective route data.

The network connecting apparatus of the present invention implements the routing function by hardware. Here, focusing on the process of discarding a packet when the protocol is TTL = 0, an interrupt is issued to the processor, and the packet data is stored in the PB.

Using this processing method, the following settings are made to verify the routing processing function. The packet from the processor is always transferred to the NIF. The packet from the NIF is transferred to the NIF. With this setting, the packet transmitted by the processor is transferred by the hardware routing function, and when TTL = 0, an interrupt occurs in the processor. The routing function can be verified by confirming the contents of the packet data stored in the PB unit and the time at which the packet returned when the interruption occurred. By setting a plurality of routes for this routing and executing packet transmission at high speed, a load for extracting the marginal performance of hardware can be easily applied, and packet loss and data error can be confirmed. For this reason, if the program can transmit a plurality of packets at the same time, it is possible to apply a load to hardware by adjusting the number of times of going around the router according to the TTL value.

FIG. 4 shows a flow of a packet in the inter-network connecting device after the execution of the packet transmission at the time of the routing function verification. PIF to NIF by processor execution instruction
The packet is forwarded to For setting the NIF, the packet is transmitted to the PB for the internal loopback of the packet data. N
The PB that has received the packet from the IF transfers the header of the packet to the RCTL. At this time, since the TTL value is not 0, the RCTL returns the destination of the packet to the PB as "NIF" based on the set routing information.

[0018] The PB transmits a packet to the received destination. The NIF sends the packet to the PB again for internal loopback. PB re-packets the packet header to RCT
Transfer to L. RCTL checks TTL and TT
Since L = 0, the instruction to interrupt the processor is P
Transfer to B. The PB generates an interrupt in the processor unit in response to an instruction from the RCTL. The processor receives the interrupt and checks the packet data stored in the PB.

A flowchart of a verification program for executing a packet flow will be described with reference to FIGS. 1. Set packet data in PB. Set TTL = 2. 2. Set the routing information in RCTL. Set to send packets to NIF. 3. The internal return information is set in the NIF. 4. Execute packet transmission. 5. Waiting for TTL = 0 interrupt. 6. Comparison of transmitted and received packet data.

FIG. 6 shows a configuration diagram of a router connecting a plurality of NIFs. As shown in FIG. 6, by connecting a plurality of NIFs and setting a plurality of route information in RCTL, a packet can be transmitted to a plurality of NIFs. In the case of the present case, the use of multicast on the protocol makes it possible to execute with one transmission command. Multicast is 1
This is a protocol for transmitting a packet to a plurality of destinations.
Transmission of a packet to a plurality of NIFs by one transmission instruction is performed according to the device specifications. If multicast is set in RCTL, packets are transmitted to a plurality of NIFs at the same time, and confirmation of the routing function capability can be verified by detecting the time required for transmission. FIG. 7 shows a flowchart of this case.

1. Set packet data in PB. T
Set TL = 2. 2. Set the routing information in RCTL. Multicast the packet sent from the processor, and
It is set so that packets are transmitted from 0 to the NIF3. 3. The internal return information is set in NIF0. 4. The internal return information is set in NIF1. 5. The internal return information is set in NIF2. 6. The internal return information is set in the NIF 3. 7. Execute packet transmission. 8. Waiting for TTL = 0 interrupt. 9. Comparison between transmitted packet data and four received packet data.

In this embodiment, four interrupts are generated in the processor. The contents to be verified are performed for four packet data.

[0023]

According to the present verification program, the TTL is used in the network connection device of the computer network system.
When = 0, the processor generates an interrupt and stores the packet in the packet buffer. Confirm and verify the routing function and performance without adding special hardware logic or connecting another device. Can be.

[Brief description of the drawings]

FIG. 1 is a flowchart of packet transfer of a verification program executed by an internal processor of a router.

FIG. 2 is a diagram illustrating a flow of packet transfer of a verification configuration by the packet generation device.

FIG. 3 is a diagram illustrating a header format of a packet in an IPv4 system.

FIG. 4 is a flowchart of a verification program executed by an internal processor of the router.

FIG. 5 is a diagram illustrating a flow of a packet in a verification program inter-network connection device that places a load on a routing control unit.

FIG. 6 is a configuration diagram of a router connecting a plurality of NIFs.

FIG. 7 is a flowchart of a verification program when a plurality of NIFs are connected.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Processor, 2 ... Packet buffer part, 3 ... Routing control part, 4 ... Line control part, 5 ... Line analyzer.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Kazuo Sugai, 1st Horiyamashita, Hadano-shi, Kanagawa Prefecture, General-purpose Computer Business Division, Hitachi, Ltd. F term in information technology (reference) 5K030 GA05 HB00 HC01 HD03 JA10 KA03 LE09 9A001 CC07 JZ25 LL05

Claims (3)

[Claims] An inter-network connection device having a function of transmitting and receiving network data, a memory function of buffering the data, a hardware function of performing routing control based on the data, and a processor for controlling these components. Means for detecting a specific field of network data when the network data is received and buffered in the memory, and executing an interrupt to the processor when a field value detected by the detecting means is a specific value. Means for comparing the buffered network data with any data set by the processor, and detecting a transmission destination based on an address field of the buffered network data by hardware for executing the routing control. And the network Means for transferring data, the network connecting unit, characterized in that it comprises a means for subtracting the data of a specific field of the network data in the hardware. 2. The apparatus according to claim 1, wherein said detecting means includes means for using a TTL field in an IP header of an IPv4 network packet and generating an interrupt to said processor when said TTL becomes zero. The network connection device according to claim 1. 3. The network connection apparatus according to claim 1, further comprising means for buffering network data when said TTL becomes zero.