JP2007215148A - Wavelength allocation method of optical packet for simplifying optical packet switch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate achievement of a super high-speed packet network by simply configuring an optical packet switch adopted for optical packet multiplex transmission wherein the whole band of all wavelengths utilized by wavelength multiplex transmission is used for transmission of individual optical packet. <P>SOLUTION: Contrivance of how to allocate contents of the optical packets to light with each wavelength simplifies an optical circuit, a photoelectric conversion circuit, and an electric control circuit or the like of the optical packet switch. Further, although the optical packet switch to which simplicity of a kind is applied cannot generate packet for controlling errors of a kind or the like, other optical packet switch can produce the control packet instead. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to simplification of an optical packet switching apparatus.

  Although optical fibers and optical amplifiers have extremely wide bandwidth transmission capability, the use of optical packet switch technology that can utilize the broadband property of optical transmission has been sought for speeding up the Internet and the like. By utilizing wavelength multiplexing technology in which light of different wavelengths is modulated with a signal having a band that can be processed electrically, and the light is optically synthesized and transmitted, the band of the optical transmission path can be utilized. For example, if 100 wavelengths are selected at appropriate intervals in the band of the optical transmission line, and the light of each wavelength is modulated at 10 Gbps, transmission in the 1 Tbps band as a whole can be performed.

  Previously, when using wavelength-multiplexed optical transmission lines, the mainstream method was to encode one optical packet with only one wavelength, but now it is necessary to process optical packets within each wavelength by wavelength. Therefore, the broadband property of light cannot be used. For example, when 100 waves of light of each wavelength modulated at 10 Gbps are combined, there is a total bandwidth of 1 Gbps, but each wavelength of light has only a bandwidth of 10 Gbps and can be easily processed by an electric circuit without using optical processing. Is possible.

  However, if a high-speed broadband optical switch (Non-Patent Documents 1 and 2) that has become available in recent years is used, one optical packet is encoded in all bands of all wavelengths used in wavelength multiplexing, and these packets are appropriately transmitted. Optical packet multiplex transmission that separates at time intervals can be efficiently realized. By switching the high-speed broadband optical switch between the packets, the destinations of all wavelengths including the packet information can be changed at once. For example, the average packet length on the Internet trunk line is about 500 bytes, but if it is encoded at 1 Tbps, it takes about 4 ns. This is a high-speed broadband optical switch that operates at a speed higher than 6 ns by arranging optical packets at intervals of 6 ns. If switched, an effective speed of about 400 Gbps can be obtained even if the packet interval is taken into consideration. The idea of not using multiplexing other than packet multiplexing is a natural concept generally used in the Internet and the like, and frequency-multiplexed wireless LAN (Non-patent Document 3) and time-division multiplexing are possible. Also in SONET / SDH (Non-patent Document 4), the entire communication band used for frequency multiplexing or time division multiplexing is used for transmission of individual packets.

  An optical packet switching device can be created by performing appropriate control by combining a large number of such high-speed broadband optical switches. However, if the optical circuit is used up to the control, the optical circuit is not so nonlinear and it is difficult to perform logical operations. Therefore, it is difficult to realize a complicated control circuit necessary for relay control of optical packets.

  Today's general information communication equipment does not need such a communication speed as to be directly connected to such a high-speed optical network. Transmission may use relatively low-speed light, but the processing of the header part and payload part inside the packet switching equipment is sufficient with an electrical network that performs electricity, and the high-speed broadband optical switch is used exclusively on the trunk line part. Is done.

  A packet network is generally composed of a large number of packet switches, and packets sent from a transmission source are generally relayed to a transmission destination via a plurality of packet switching devices. The packet has a header part and a payload part. A packet switching device generally has a plurality of inputs and outputs. A packet switching device in a packet network and a terminal device connected to the packet network are identified by an address. As special addresses, there are a multicast address and a broadcast address that collectively identify a plurality of devices. The header part includes various control information necessary for the packet switching apparatus to process the packet. The specific content of the header part varies depending on the packet network, and includes, for example, the address of the transmission source and transmission destination, information for preventing an infinite loop of packet transmission, and information indicating the priority of the packet. The contents of the header part may be rewritten by the packet switching device as necessary. The transmission destination of the header part is used by the packet switching device to determine which output the packet is relayed to, or whether the packet switching device itself is the transmission destination and the packet should be received by itself. The The transmission source of the header part is used as the transmission destination when sending a control packet notifying the transmission source when an error or the like occurs in the transmission destination packet, and who is the transmission source at the transmission destination It is also used to know what.

An optical packet network is a type of packet network, and packets are transmitted as light packets using light. The optical packet network may be used in an integrated manner with an electrical packet network that operates on electricity. In the current practical optical packet switching equipment, optical packets are once converted into electrical packets and processed, but large-scale parallel processing is required to secure broadband performance of optical transmission by electrical processing. Various studies have been conducted on methods of processing light as it is to make use of the broadband nature of light. Photoelectric converters such as laser diodes and photodiodes are used for conversion between optical packets and electrical packets.
Katsuya Ikezawa et al., “Development of optical packet network elemental technology”, IEICE Technical Report, PN, April 2005. Keiichi Nashimoto et al., “Development of ultrafast PLZT thin film optical switching subsystem”, IEICE Technical Report, PN, October 2005. □ Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) specifications: High-speed Physical Layer in the 5 GHz Band □, IEEE 80S A. Malis, W.M. Simpson, □ PPP over SONET / SDH □, RFC 2615, June 1999.

  The problem to be solved by the present invention is the simplification of the circuit of the optical packet switching apparatus.

  The present invention simplifies the circuit of an optical packet switching apparatus by devising a method for assigning the contents of optical packets to light of each wavelength in optical packet multiplex transmission.

  According to the first aspect of the present invention, the header portion of the optical packet is included only in some wavelengths, so that the optical packet is relayed only by handling those wavelengths.

  The idea of optical packet multiplex transmission is not to handle each wavelength individually as in wavelength routing, but to use all communication bands of all wavelengths used for wavelength multiplexing for transmission of individual packets. The content of one packet is distributed over all wavelengths, and separate packets are separated on the time axis. This concept itself is naturally performed in the Internet and the like, and in frequency-multiplexed wireless LAN and time-division-multiplexed SONET / SDH optical transmission that is frequency-multiplexed by fast Fourier transform, All communication bands used in division multiplexing are used for transmission of individual packets.

  Unlike wavelength division multiplexing transmission, wireless LAN frequency multiplexing and SONET / SDH time division multiplexing are performed by electrical processing, so that all signals are naturally subjected to electrical processing. The speed is low enough to allow electrical processing. Therefore, to which frequency and time the packet contents are assigned can be freely changed by simple electric processing, and there is no particular limitation. On the contrary, the order of bits is often actively changed in order to improve burst error correction capability. On the other hand, in wavelength division multiplex transmission, each wavelength is transmitted at a speed that is about the limit of electrical processing, and it is not easy just to convert a signal included in each wavelength into an electrical signal. In order to create a simple optical packet switching device, it is necessary to process as many wavelengths as possible so that the broadband property of light can be used, and to reduce the number of wavelengths that require electrical processing.

  Nonetheless, it is extremely difficult to carry out the complicated control necessary for packet relay using light. The logical operation for control requires non-linear processing. For light with poor non-linearity, a large circuit is required even for simple control. However, the control necessary for packet relay is only necessary in units of packets, not in units of bits. If the average packet transmission time or packet interval is about several ns, the control is sufficient even if it is performed by an electric circuit. Further, the information necessary for packet relay is only the information contained in the header part. The high-speed transmission of the payload portion can make full use of the broadband property of light, but the header portion does not require that much bandwidth and can be processed by an electric circuit.

  Therefore, using optical packet multiplex transmission, the header part of the optical packet is taken out, converted to electricity, processed by an electric circuit, the contents are rewritten as necessary, returned to light, and merged with the original optical packet, An optical packet switching apparatus that takes advantage of optical broadband characteristics can be realized by collectively switching to a transmission destination with a high-speed broadband optical switch according to the processing result. At this time, the optical packet switching apparatus can be simplified by processing as many wavelengths as possible with light.

  An optical packet switching apparatus using optical packet multiplex transmission takes out the header portion of the optical packet input for all the optical inputs, performs photoelectric conversion, and relays or receives the optical packet according to the contents. In preparation for the case where an optical packet is simultaneously input to a plurality of optical inputs, a header readout circuit is required for each optical input. Since the readout circuit of the header part for each optical input is proportional to or more than the number of wavelengths including the header part, by reducing the number of wavelengths including the information of the header part, the optical packet switching device The circuit scale can be kept small. This is realized by the method of assigning optical packet contents to each wavelength according to claim 1. Note that the wavelength including the header portion information may include the payload portion information.

  A second aspect of the present invention is an optical packet switching apparatus using the method for assigning optical packet contents to each wavelength according to the first aspect.

  In addition, at the boundary between the packet network by electrical processing and the optical packet network by optical packet multiplexing, a relatively low-speed packet to be electrically processed is encoded in all bands of all wavelengths used for wavelength multiplexing to form an optical packet, and conversely Since optical packets distributed over all wavelengths used for multiplexing are decoded and used as electric processing packets, photoelectric conversion is required for all wavelengths used for wavelength multiplexing, and the circuit scale of the boundary optical packet switching apparatus increases to some extent. An optical packet network based on optical packet multiplexing is positioned as a trunk line that collects and relays a large number of packets from electrical processing. Therefore, when converting packets from electrical processing to optical packets based on optical packet multiplexing, use as many wavelengths as possible. And you should do efficient encoding.

  On the other hand, in the center of an optical packet network based on optical packet multiplexing in which an optical packet switching device is connected only to another optical packet switching device, decoding and encoding of the header portion of the optical packet is necessary, but the payload portion is a packet that is sent and received by itself. No decoding or encoding is required except for. The packets sent and received by the optical packet switching equipment are generally small amounts for route control and error notification. Even if the encoding method of these packets is somewhat inefficient, the performance of the entire optical network Does not affect much. Therefore, in order to further simplify the central optical packet switching apparatus and the like, there is room for contrivance in the encoding method of packets transmitted and received by itself.

  According to the third aspect of the present invention, in order to reduce the circuit scale of the optical packet switching apparatus that relays the optical packet as it is without transmitting or receiving the optical packet as much as the central optical packet switching apparatus, the optical packet switching apparatus By including the header part and payload part of the optical packet transmitted / received in only a small number of wavelengths, the optical packet is transmitted / received only by decoding and encoding those wavelengths.

  The packet network needs to use an efficient packet format that makes the best use of the capabilities of the transmission path and packet switching device as much as possible for the packet to be relayed, but even if a somewhat inefficient packet format is used for a small number of packets, the packet network The overall performance is not significantly affected. For example, if the amount of packets sent or received by the packet switching apparatus is 0.01% of the total, even if the efficiency of the packet format is 10 times worse than other packets, the overall efficiency of the packet network is Only about 0.1% decrease.

  Therefore, when the amount of packets transmitted or received by the optical packet switching apparatus is small, only a part of the wavelengths are allocated to the header part and the payload part as in claim 3 only for those packets. The circuit of the optical packet switching apparatus can be simplified as compared with the case where all wavelengths to be used are assigned. The number of photoelectric converters necessary for the optical packet switching apparatus to transmit or receive itself is only required to be proportional to the number of the partial wavelengths.

  According to a fourth aspect of the present invention, there is provided an optical packet switching device that is simplified by using the method for assigning optical packet contents to each wavelength according to the third aspect.

  According to a fifth aspect of the present invention, in the method of assigning optical packet contents to each wavelength according to the first aspect, the optical circuit for taking out and rewriting the header portion without reducing the overall transmission rate and the circuit associated therewith are simplified. It is for making it.

  The processing to extract or replace only a specific wavelength for wavelength multiplexing processing requires steeper characteristics, higher accuracy, and higher stability as the wavelength interval between the wavelength and other wavelengths is smaller. , Realization becomes difficult. However, there are restrictions on the wavelength range that can be transmitted with low loss by an optical fiber and the wavelength range that can be efficiently amplified by an optical amplifier. Therefore, in order to secure as many wavelengths as possible within the range, the wavelength interval should be small. Therefore, sparse wavelength multiplexing using simpler equipment is used in applications where high transmission rates are not required, and dense wavelength multiplexing using more serious equipment is used in applications where higher transmission speeds are required. Is used. However, the wavelength interval cannot be made as close as possible, and a certain amount of interval according to the speed of modulating each wavelength is necessary.

  When the number of wavelengths used in the header portion is small among all wavelengths used in wavelength multiplexing, the wavelength interval between wavelengths used in the header portion and the wavelength and payload used in the header portion as in claim 5 Even if the wavelength interval with the wavelength used only for the portion is rough, the required wavelength width does not increase as a whole, but the header portion can be easily taken out and rewritten, and only the header portion needs to be taken out. This is useful for simplifying the circuit of an optical packet switching apparatus, which is often the case.

  According to a sixth aspect of the present invention, there is provided an optical packet switching apparatus that is simplified by using the method for assigning optical packet contents to each wavelength according to the fifth aspect.

  According to a seventh aspect of the present invention, based on the same idea as in the fifth aspect, in the method of assigning the optical packet contents to each wavelength according to the second aspect, the header portion and the payload portion are taken out and rewritten without significantly reducing the overall transmission rate. This is for simplifying the optical circuit.

  The wavelength used in the header portion of all wavelengths used in wavelength multiplexing is the same as in claim 5. However, if the number of wavelengths used only in the payload portion is small, it is necessary as a whole even if they are spaced. The width of the optical wavelength does not increase at all or not so much, but the transmission and reception of the payload part becomes easy, and the optical packet switching circuit that relays the optical packet as it is without transmitting or receiving the optical packet itself. Useful for simplification.

  An eighth aspect of the present invention relates to an optical packet switching apparatus simplified by using the method for assigning optical packet contents to each wavelength according to the seventh aspect.

  A ninth aspect of the invention is to generate a control packet such as an error while simplifying the optical packet switching apparatus using the optical packet allocation method of the third aspect.

  In a packet network, it may be necessary to generate a control packet based on the contents of a relayed packet and send it to a transmission source. For example, when a packet cannot be relayed any more, a packet for notifying the transmission source of an error may be sent. The necessity of generating the control packet can be understood only from the information in the header part, but in order to know which packet caused the error etc. at the sender, in general, not only the header part of the packet that caused the generation of the control packet but also the payload Part of the information of the part is also necessary, and that part needs to be included in the control packet.

  However, since the optical packet switching apparatus using the optical packet allocation method of claim 3 cannot decode the contents of the wavelength used in the payload portion of a general optical packet, it generates a control packet including the same. It is not possible.

  Therefore, in the optical packet switching apparatus using the optical packet allocation method of claim 3, it is necessary to generate a control packet without directly generating a control packet for a packet whose payload part cannot be decoded. Write the information in the header and temporarily transfer it to the sender. In the header part, there is room for that from the beginning. This temporary packet is converted into a formal control packet when it reaches an optical packet switching apparatus that can decode the payload portion of a general packet. The boundary optical packet switching device located at the boundary between the optical packet network and the electrical packet network can decode the payload of a general optical packet to convert it into an electrical packet. It always happens on the device.

  According to the present invention, in an optical packet network that transmits an optical packet having a header portion and a payload portion by optical packet multiplex transmission that uses all bands of all wavelengths used for wavelength multiplex transmission for transmission of individual optical packets, It is possible to simplify the optical packet switching apparatus that relays the optical packet toward the optical network without significantly affecting the performance of the entire optical network.

  According to claim 1 and claim 2, when the header part is included in only a small number of wavelengths, the circuit of the part that handles the header part in the optical packet switching device, compared with the case where the header part is included in a large number of wavelengths. Is simplified.

  According to claims 3 and 4, an optical packet switching apparatus using a special optical packet format that is transmitted and received by an optical packet switching apparatus that relays optical packets without transmitting or receiving optical packets. When the header part and the payload part are included in only a small number of wavelengths, it is simplified. At that time, the efficiency of the optical packet network does not decrease so much.

  According to the fifth and sixth aspects, the optical circuit of the part that handles the header portion of the optical packet switching device is simplified.

  According to claims 7 and 8, an optical packet switching apparatus using a special optical packet format that is transmitted and received by an optical packet switching apparatus that relays optical packets without transmitting or receiving optical packets. The optical circuit is simplified.

  According to the ninth aspect of the present invention, the control packet including the payload of the optical packet causing an error or the like is transferred to another optical packet while simplifying the optical packet switching apparatus using the optical packet allocation method of the third aspect. It can be generated by an exchange device.

  An optical packet switching apparatus having two optical inputs and outputs can be configured as shown in FIG. In FIG. 1, the portion above the dotted line is a portion that performs control by an electric circuit, and the portion below the dotted line is a portion that performs processing by light. Photoelectric conversion is performed at the boundary.

In FIG. 1, the wavelength including the header portion is extracted from the optical packet input from the optical input 10 by the header extraction optical circuit 20, and sent to the electrical control circuit 70. As a result of the processing of the header portion, a new header portion is created and combined with a wavelength including only the payload portion by the header portion combining optical circuit 40. During the time required for processing in the electrical control circuit 70, the payload portion passes through the optical fiber delay line 30, and the time difference between the header portion and the payload portion is eliminated. The optical fiber delay line is an optical fiber that is long to some extent, and generates a delay that is obtained by dividing the length by the speed of light.
The optical packet combined with the new header part is output as an optical packet from the optical output 60 via the optical buffer 50.
The optical buffer 50 shifts the time of each optical packet and keeps an appropriate optical packet interval so that a collision does not occur when it is necessary to simultaneously transmit optical packets from a plurality of inputs to one output. The electrical control circuit 70 controls how much each optical packet input to the optical buffer is delayed.
The electrical control circuit 70 also performs processing for transmitting an optical packet transmitted by itself as an optical packet 80 output from the electrical circuit, and receiving an optical packet received by itself as an optical packet 90 input to the electrical circuit.
The boundary optical packet switching apparatus also has an electrical input / output 75, relays the electrical packet received from the electrical input / output 75 as an optical packet 80 output from the electrical circuit, and electrically receives the electrical packet received as the optical packet 90 input to the electrical circuit. A process of relaying to the input / output 75 is also performed. The central optical packet switching device does not have an electrical input / output 75.

  The optical buffer 50 can be composed of a plurality of optical fiber delay lines 30 having different delay amounts as shown in FIG. FIG. 2 shows an optical buffer capable of adding three types of delays to an optical packet from three inputs. An appropriate input is selected by a 3: 1 optical multiplexer 100 for each optical fiber delay line 30 having a different length. The 4: 1 optical multiplexer 120 selects an optical fiber delay line to be output at present. If no optical fiber delay line should be output, the 4: 1 optical multiplexer 120 selects the dummy input 110. In order to adjust the packet interval more precisely and improve the collision avoidance ability, optical fiber delay lines with various delays are prepared.

  As shown in FIG. 3, the optical multiplexer includes a high-speed broadband 2: 1 optical switch 130 controlled by electricity. The high-speed broadband 2: 1 optical switch 130 can be configured by using a material whose refractive index changes at high speed due to electricity, such as LN or PLZT, in combination with an interferometer. The optical multiplexer configured in this way can be an optical demultiplexer if the input and output are used in reverse.

  1 and 2 have the effect of reducing the number of wavelengths exchanged between the header extraction optical circuit 20 and the header synthesis optical circuit 40 and the electrical control circuit 70 in FIG. Reduction and simplification of the electrical control circuit 70.

  In addition to the effects of claims 1 and 2, claims 3 and 4 reduce the number of photoelectric conversion circuits applied to the optical packet 80 output from the electric circuit and the optical packet 90 input to the electric circuit in FIG. This leads to simplification of the control circuit.

  Claims 5 and 6 alleviate the requirements for wavelength discrimination characteristics and stability required for the header extraction optical circuit 20 and the header synthesis optical circuit 40 in FIG. 1, leading to simplification.

  Claims 7 and 8 show the wavelength discrimination characteristics required for the photoelectric conversion circuit and the stability thereof required for the optical packet 80 output from the electric circuit and the optical packet 90 input to the electric circuit in FIG. Mitigates and leads to its simplification.

  Claim 9 is a simplified optical packet switching device that takes advantage of the effect of claim 3 in FIG. 1, although an optical packet that can be decoded as an optical packet 90 input to an electric circuit is in a special form. This is a method for generating a control packet such as an error including information on the payload portion of an optical packet of a format other than the above. For a packet in which an error or the like has occurred, a new header to which information for generating a control packet such as the type of error or the like is added is combined with the original payload by the header combining optical circuit 40 and transferred toward the transmission source. When this optical packet reaches another optical packet switching device that can decode the general optical packet as an optical packet 90 that is input to the electric circuit, a formal control packet is generated.

  FIG. 4 shows a wavelength allocation form. FIG. 4 a) shows a wavelength assignment form in which the header portion is assigned to a small number of wavelengths based on claims 1 and 2. FIG. 4B) is a wavelength assignment mode in which the wavelength interval of the header portion is further roughened based on claims 5 and 6. FIG. 4 c) shows a wavelength assignment form in which the header part and the payload part are assigned to a small number of wavelengths based on claims 3 and 4. At this time, the payload length that can be included in the packet of the same time length is shorter than that in the case of FIG. 4a), but if this becomes a problem, the packet time is increased or the packet is divided into a plurality of packets. Can be dealt with by fragmentation fragmentation. FIG. 4 d) shows a wavelength allocation mode in which the wavelength interval between the header portion and the payload portion is rough based on claims 7 and 8.

  As one embodiment of the present invention, an optical packet switching device that operates as a router for an IPv4 Internet trunk can be created. At this time, the control packet for an error or the like according to claim 9 corresponds to an Internet ICMP packet. If the IPv4 header ignoring the option is used as it is, the header of the packet is 20 bytes. Further, in order to generate ICMP by the method of claim 9, it is necessary to add 10 bytes of information such as the type of ICMP to be generated and the IP address of the router to which ICMP is originally generated to the header part. The length is 30 bytes. The IPv4 ICMP packet needs to include the IP header of the IPv4 packet causing ICMP and the subsequent 64 bits. The payload portion corresponds to the portion after the IPv4 header as it is.

  At this time, assuming that the average packet length of the Internet trunk line including the header part of 30 bytes is 500 bytes and the maximum packet length is 1500 bytes, and 100 wavelengths modulated at 10 Gbps are used, the total transmission speed becomes 1 Mbps, and the packet The time required for transmission is an average of 4 ns and a maximum of 12 ns, and an optical fiber delay line having only the maximum packet transmission time can be realized by an optical fiber of about 3.6 m. If the packet interval is 6 ns, the average effective transmission rate is 400 Gbps. In addition, the average number of bytes per wavelength is 5 bytes and a maximum of 15 bytes. Therefore, if the header portion is assigned to 10 wavelengths according to claims 1 and 2, those wavelengths are at least 3 bytes. If the packet length is less than 300 bytes, the payload to be sent before the header transmission is completed is exhausted, but the average performance is not significantly affected. According to claim 3 and claim 4, the central router as a central optical packet switching apparatus having only optical input / output can transmit and receive only 10 wavelengths of light for the header portion, and the time required for packet transmission is maximized. If it is limited to 12 ns, the central router can send and receive a packet of up to 150 bytes, which is larger than 68 bytes which is the minimum limit in the IPv4 standard.

  As another embodiment of the present invention, an optical packet switching device that operates as a router for an IPv6 Internet trunk can be created. At this time, assuming the same assumption as in the IPv4 embodiment, the IPv6 header is 40 bytes, and the contents of the packet causing the ICMP are packed in the ICMP packet as long as the ICMP packet does not exceed 576 bytes. The IPv6 standard is almost the same as the implementation as a router of the IPv4 Internet trunk line except for the three points that a link fragment is necessary because a packet of at least 1280 bytes must be transmitted and received.

  As yet another embodiment of the present invention, an optical packet switching device that operates as a data link layer switch instead of a router can be created.

  It is a block diagram of an optical packet switching apparatus.   It is a block diagram inside an optical buffer.   It is a block diagram of an optical multiplexer.   It is a figure of the mode of allocation to each wavelength of the optical packet content.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Optical input 20 Header part extraction optical circuit 30 Optical fiber delay line 40 Header part synthetic | combination optical circuit 50 Optical buffer 60 Optical output 70 Electrical control circuit 75 Electrical input / output 80 Optical packet output from electrical circuit 90 Optical packet input to electrical circuit 100 3: 1 optical multiplexer 110 dummy input 120 4: 1 optical multiplexer 130 high-speed broadband 2: 1 optical switch

Claims (9)

An optical packet having a header portion and a payload portion is transmitted by optical packet multiplex transmission that uses the entire bandwidth of all wavelengths used for wavelength multiplex transmission to transmit individual optical packets, and is relayed to a transmission destination by an optical packet switching device. In the optical packet network
A method of assigning optical packet contents to each wavelength, in which only a part of the wavelengths to be used is assigned to the header part, so that only the wavelength to which the header part is assigned can be decoded or encoded to relay the optical packet.   2. An optical packet switching apparatus having a switching mechanism by means of a high-speed broadband optical switch and an electrical control circuit for optical packets transmitted using all bands of all wavelengths used in wavelength division multiplexing transmission. An optical packet switching apparatus using an allocation method to An optical packet having a header part and a payload part is transmitted by optical packet multiplex transmission that uses all bandwidths of all wavelengths used for wavelength multiplex transmission to transmit individual optical packets, and is relayed to a destination by an optical packet switching device. In the optical packet network
As a special optical packet format that optical packet switching equipment that relays optical packets as they are without transmitting or receiving optical packets themselves,
By assigning only a part of the wavelengths to be used to the header part and the payload part, the optical packet switching device only needs to decode or encode the part of the wavelengths, and assign the optical packet contents to each wavelength. Method.   It has a switching mechanism by means of a high-speed broadband optical switch and an electrical control circuit for optical packets transmitted using all bands of all wavelengths used in wavelength division multiplexing transmission, and does not transmit or receive optical packets by itself. An optical packet switching apparatus that performs relaying as it is, and uses the method for assigning optical packet contents to each wavelength according to claim 3 as a special optical packet format for transmitting and receiving itself. The method of assigning optical packet contents to each wavelength according to claim 1,
By roughly distributing the wavelength assigned to the header part,
A method of assigning the contents of optical packets to each wavelength, which allows easy extraction and rewriting of those wavelengths.   6. An optical packet switching apparatus having a switching mechanism by an optical high-speed broadband optical switch and an electrical control circuit for optical packets transmitted using all bands of all wavelengths used in wavelength division multiplexing transmission. An optical packet switching apparatus using an allocation method to The method for assigning optical packet contents to each wavelength according to claim 3,
By roughly distributing the wavelengths used by the optical packet switching equipment that relays optical packets as they are without transmitting or receiving optical packets themselves,
A method of assigning the contents of optical packets to each wavelength, which allows easy extraction and rewriting of those wavelengths.   It has a switching mechanism by means of a high-speed broadband optical switch and an electrical control circuit for optical packets transmitted using all bands of all wavelengths used in wavelength division multiplexing transmission, and does not transmit or receive optical packets by itself. An optical packet switching apparatus that performs relaying as it is, and uses the method for assigning optical packet contents to each wavelength according to claim 7. An optical packet having a header part and a payload part is transmitted by optical packet multiplex transmission that uses all bandwidths of all wavelengths used for wavelength multiplex transmission to transmit individual optical packets, and is relayed to a destination by an optical packet switching device. In the optical packet network
The optical packet A relayed by the optical packet switching apparatus 1 using the method for assigning the special optical packet contents to each wavelength according to claim 3 causes an error or the like, and uses the information in the payload part of the optical packet A to control packets. It is necessary to generate B and notify the transmission source, but when the optical packet switching apparatus 1 cannot decode the wavelength used in the payload portion of the optical packet A,
In the optical packet switching device 1, information such as an error is recorded in the header part of the optical packet A, and the optical packet C with the payload part is transferred to the transmission source.
When the optical packet C arrives at the optical packet switching apparatus 2 that can decode the payload portion of the optical packet C,
By generating the control packet B based on the contents of the optical packet C in the optical packet switching device 2,
A method for generating a control packet B, in which the optical packet switching apparatus 1 only needs to decode or encode a part of wavelengths.

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