Optical Access Network Architecture for Distributed Edge Data Centers Based on Asynchronous Optical Packet Switching

Abstract

The present invention discloses an optical access network architecture for a distributed edge data center based on asynchronous optical packet switching, belonging to the field of optical access networks. The data access end modulates the uplink signal to be processed to a preset wavelength and transmits the uplink signal to be processed by using a wavelength division multiplexer with multiple wavelengths; the HEM packet header extraction module separates the optical packet header and the payload from the access signal; the optical line terminal analyzes the optical packet header to obtain the target address and priority information of each signal to be processed; the delay optical fiber caches the payload of each signal to be processed; the optical switching matrix determines the switching state of the optical switching matrix according to the target address of each signal to be processed, and transmits the payload of each signal to be processed to the target address according to the priority information. The optical access network architecture of the present invention can realize the random access of a large number of terminal user burst services, improve the scalability of the system, and can solve the problem of wavelength conflict caused by two or more burst tasks at the same time.

Description

Technical Field

[0001] The present invention relates to the technical field of optical access networks, and particularly to an optical access network architecture for a distributed edge data center based on asynchronous optical packet switching. Background Art

[0002] Data centers in cloud computing are usually far from most users. With the rapid growth of network traffic, its aggregated service mode will cause large propagation delays due to long-distance network transmission and service conflicts, and cannot effectively process large-scale delay-sensitive services. In the face of the challenges of network latency and application availability, edge data centers (EDCs) have emerged. Compared with optical circuit switching (OCS) and optical burst switching (OBS), optical packet switching (OPS) technology has finer switching granularity, larger capacity, more transparent rate and format, and can improve network resource utilization. Among them, asynchronous optical packet switching (AOPS) technology is more suitable for random and burst services.

[0003] With the diversification of edge data center service types, optical access network technology is also constantly changing. Passive optical networks (PONs) applied to broadband access mainly adopt time division multiplexing (TDM) technology based on optical splitters. By using optical splitters with different splitting ratios, flexible configuration of different system scales can be achieved under different bandwidth requirements. However, optical splitters not only cause large signal attenuation and shorten the transmissible distance, but also their small splitting ratios limit the scale and flexibility.

[0004] Due to the lack of mature optical buffers, electrical caching has become a bottleneck for resolving upstream signal conflicts in high-speed large-capacity optical access networks. In addition, since the optical line terminal (OLT) is far from the ONU, the OLT arbitrates and uses TDM technology to allocate transmission time slots for each ONU, which not only introduces large path delays but also reduces flexibility. Summary of the Invention

[0005] The present invention provides an optical access network architecture for a distributed edge data center based on asynchronous optical packet switching, which can meet the interaction, storage, and computing requirements of distributed, massive, heterogeneous, and burst services in the edge computing scenario, and solve the problem of conflicts that occur when two or more signals from different groups are transmitted simultaneously at the same wavelength.

[0006] An embodiment of the present invention provides an optical access network architecture for a distributed edge data center based on asynchronous optical packet switching, including: a data access end, configured to access n×m upstream signals to be processed, divide the n×m upstream signals to be processed into m groups, modulate the n upstream signals to be processed in each group to a preset wavelength, and transmit the n upstream signals to be processed in each group by using a wavelength division multiplexer with multiple wavelengths; m+1 HEM packet header extraction modules, wherein m HEM packet header extraction modules are connected to the data access end and the optical switching matrix, and the other HEM packet header extraction module is connected to the optical line terminal. The HEM packet header extraction module is configured to separate the optical packet header and the payload of the access signal; the optical line terminal is configured to amplify multiple downstream signals to be processed by an erbium-doped fiber amplifier and output them to the HEM packet header extraction module, and receive and analyze the optical packet headers output by the HEM packet header extraction module to obtain the target address and priority information of each signal to be processed; a 1×m optical splitter, which is arranged between the optical switching matrix and the other HEM packet header extraction module; a delay fiber, configured to cache the payload of each signal to be processed; the optical switching matrix is configured to receive the payload of each signal to be processed sent by the HEM packet header extraction module and the target address and priority information of each signal to be processed sent by the optical line terminal, determine the switching state of the optical switching matrix according to the target address of each signal to be processed, and transmit the payload of each signal to be processed to the target address according to the priority information.

[0007] Optionally, in an embodiment of the present invention, the HEM packet header extraction module includes: a 1×2 coupler is added before the HEM in the direction of the downstream signal transmission, and an optical circulator is added after the HEM. One path of the 1×2 coupler inputs the packet into the HEM in the direction of the downstream signal, and the payload output from the first port a of the HEM continues to descend through the optical circulator 1→2 and enters the subsequent module. The upstream signal enters the other path of the 1×2 coupler through the reverse direction of the optical circulator 2→3 for upstream signal transmission.

[0008] Optionally, in an embodiment of the present invention, the HEM includes:

[0009] a beam splitting coupler, a first multimode interferometer MMI1, a second multimode interferometer MMI2, a first semiconductor optical amplifier SOA1, and a second semiconductor optical amplifier SOA2;

[0010] Wherein, the first semiconductor optical amplifier SOA1 and the second semiconductor optical amplifier SOA2 are respectively in two-way communication with the first multimode interferometer MMI1 and the second multimode interferometer MMI2, and the carrier lifetimes of the first semiconductor optical amplifier SOA1 and the second semiconductor optical amplifier SOA2 are not equal, which are used to achieve signal amplification and phase change;

[0011] The optical splitter coupler is used to divide the access signal into signal light and control light with unequal powers according to the splitting ratio, wherein the power of the signal light is less than that of the control light. The signal light is access to the first multimode interferometer MMI1, and the control light is access to the second multimode interferometer MMI2 after passing through the delay optical fiber;

[0012] The first output terminal a of the second multimode interferometer MMI2 is connected to the coupler in the HEM packet header extraction module for outputting the payload, and the second output terminal b is connected to the optical line terminal for outputting the optical packet header.

[0013] Optionally, in an embodiment of the present invention, the splitting ratio of the optical splitter coupler is between 95:5 and 99:1.

[0014] Optionally, in an embodiment of the present invention, the optical line terminal includes:

[0015] An edge data center for polling the received downlink signals to be processed;

[0016] An optical transmitting module for receiving and sending the downlink signals to be processed.

[0017] Optionally, in an embodiment of the present invention, when at least two of the signals to be processed in different packet payloads are transmitted simultaneously at the same wavelength during the process of transmitting the payloads of multiple signals to be processed to the target address, the optical switching matrix is further used to determine the transmission order according to the priority information of the payloads, and transmit the multiple payloads according to the transmission order. Wherein, the payloads waiting to be transmitted are cached in the delay optical fiber of the optical switching matrix.

[0018] Optionally, in an embodiment of the present invention, the delay time of the delay optical fiber of the optical switching matrix is an integer multiple of the receiving time of the optical line terminal.

[0019] Optionally, in an embodiment of the present invention, when the number of groups of the payloads waiting to be transmitted is greater than the number of the delay optical fibers of the optical switching matrix, the delay optical fiber of the optical switching matrix is further used to discard the payload with the lowest priority so that the number of the payloads waiting to be transmitted is equal to the number of the delay optical fibers of the optical switching matrix.

[0020] The optical access network architecture of the distributed edge data center based on asynchronous optical packet switching according to the embodiments of the present invention can meet the application requirements of the access network. By adopting asynchronous optical packet switching technology and wavelength division multiplexing technology, it can achieve real-time, flexible and random access for a large number of terminal users' burst services, improve the scalability of the system, and reduce the additional path delay by using a local conflict resolution solution, and can solve the problem of wavelength conflict when there are two or more task signals to be processed generating uplink data simultaneously.

[0021] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the following description of the embodiments in conjunction with the drawings, wherein:

[0023] Figure 1 FIG. 1 is a block diagram of an optical access network architecture of a distributed edge data center based on asynchronous optical packet switching according to an embodiment of the present invention;

[0024] Figure 2 FIG. 2 is a schematic structural diagram of an optical access network architecture of a distributed edge data center based on asynchronous optical packet switching according to an embodiment of the present invention;

[0025] Figure 3 FIG. 3 is a schematic structural diagram of a HEM according to an embodiment of the present invention;

[0026] Figure 4 FIG. 4 is a schematic diagram of an optical circulator according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

[0028] Figure 1 FIG. 1 is a block diagram of an optical access network architecture of a distributed edge data center based on asynchronous optical packet switching according to an embodiment of the present invention.

[0029] As Figure 1 shown, the optical access network architecture of the distributed edge data center based on asynchronous optical packet switching includes: a data access end, m + 1 HEM packet header extraction modules, an optical line terminal (OLT), a 1×m optical splitter, a delay fiber Figure 1(not shown) and an optical cross-connect (OXC).

[0030] Among them, the data access end is used to access n×m upstream signals to be processed, divide the n×m upstream signals to be processed into m groups, modulate the n upstream signals to be processed in each group to a preset wavelength, and use a multi-wavelength wavelength division multiplexer to transmit the n upstream signals to be processed in each group;

[0031] m + 1 HEM packet header extraction modules, among which, m HEM packet header extraction modules are connected to the data access end and the optical cross-connect, and the other HEM packet header extraction module is connected to the optical line terminal. The HEM packet header extraction module is used to separate the optical packet header and the payload from the access signal;

[0032] The optical line terminal is used to amplify the multiple downstream signals to be processed and output them to the HEM packet header extraction module through an erbium-doped fiber amplifier (EDFA), and receive and analyze the optical packet headers output by the HEM packet header extraction module to obtain the target address and priority information of each signal to be processed;

[0033] A 1×m optical splitter is arranged between the optical cross-connect and the other HEM packet header extraction module;

[0034] The delay fiber is used to cache the payload of each signal to be processed;

[0035] The optical cross-connect is used to receive the payload of each signal to be processed sent by the HEM packet header extraction module and the target address and priority information of each signal to be processed sent by the optical line terminal, determine the switching state of the optical cross-connect according to the target address of each signal to be processed, and transmit the payload of each signal to be processed to the target address according to the priority information.

[0036] Such as Figure 2As shown, in an embodiment of the present invention, the data access end can realize the real-time access of burst tasks (the uplink signals to be processed in the present invention) of n×m ONUs, modulate the burst tasks to a preset wavelength through a modulation signal, group the burst tasks by using the n-wavelength WDM (Wavelength Division Multiplexing) technology, and transmit the burst tasks in groups to meet the requirements of interaction, storage, and calculation for distributed, massive, heterogeneous, and burst services in the edge computing scenario. An erbium-doped fiber amplifier is used to pre-amplify the signal to compensate for the energy loss caused by the 1×m beam splitter. The wavelength division multiplexing (WDM) technology is used to allocate unique uplink and downlink wavelengths to each optical network unit (ONU) to form a WDM-PON system, which has great advantages in terms of transmission bandwidth, power budget, user management, information security, and elimination of rate bottlenecks. Combining the asynchronous optical packet technology with the WDM technology can make more full use of the fiber capacity and improve the scale, speed, scalability, and flexibility of the optical access network.

[0037] In an embodiment of the present invention, during the process of transmitting the payloads of multiple signals to be processed to the target address, if at least two signals to be processed in different packet payloads are transmitted simultaneously with the same wavelength, the optical switching matrix is further configured to determine the transmission order according to the priority information of the payloads and transmit multiple payloads according to the transmission order, wherein the payloads waiting to be transmitted are cached in the delay fiber of the optical switching matrix.

[0038] Specifically, all ONUs in the system are divided into m groups by a 1×m beam splitter, the number of each group is n, and each ONU in the group is assigned a different wavelength. For the uplink signal, if two or more signals from different groups are transmitted simultaneously with the same wavelength, a conflict will occur. Based on this distributed edge data center optical access network architecture, a conflict resolution mechanism based on an optical switching matrix (OXC) and a fiber delay line (FDL) is proposed. The EDC analyzes the wavelength and priority of each uplink signal according to the packet header information. When a conflict occurs, the optical packet with a higher priority is allowed to pass, while the optical packet with a lower priority is switched to the fiber delay line for caching.

[0039] In an embodiment of the present invention, the delay fiber of the optical switching matrix is further configured to discard the payload with the lowest priority when the number of groups of the payloads waiting to be transmitted is greater than the number of the delay fibers of the optical switching matrix, so that the number of the payloads waiting to be transmitted is equal to the number of the delay fibers of the optical switching matrix.

[0040] It should be noted that the delay time of the delay fiber of the optical switching matrix is an integer multiple of the optical line terminal reception time.

[0041] Specifically, the embodiments of the present invention adopt a group B of FDLs, and the delays are integer multiples of the OLT-side RX reception time τ (τ, …, Bτ). Therefore, B conflicting packets can be stored simultaneously within the FDL group. If the number of generated conflicting packets exceeds B, the packet with the lowest priority will be discarded.

[0042] In the embodiments of the present invention, the optical line terminal includes:

[0043] An edge data center for polling the received downlink signals to be processed;

[0044] An optical transmitting module for receiving and transmitting the downlink signals to be processed.

[0045] Specifically, the OLT side of the optical line terminal includes an edge data center EDC and an optical transceiver module TX / RX. The address and priority information are included in the packet header. The EDC controls the switching state of the optical switching matrix OXC according to the analysis result of the packet header, so as to switch the corresponding payload to the appropriate destination unit. The fiber delay line FDL is used to cache the packet payload and wait for the processing result of the control unit.

[0046] Since the data flow direction of the HEM can only flow unidirectionally, in order to enable bidirectional signal transmission, in the direction of the downlink signal transmission, a 1×2 coupler is added before the HEM, and an optical circulator is added after the HEM. One path of the 1×2 coupler inputs the packet into the HEM in the direction of the downlink signal, and the payload output from the first port a of the HEM continues to travel downward through the optical circulator 1→2 and enters the subsequent module. The uplink signal enters the other path of the 1×2 coupler through the reverse direction of the optical circulator 2→3 for uplink signal transmission.

[0047] The HEM includes:

[0048] A splitting coupler, a first multimode interferometer MMI1, a second multimode interferometer MMI2, a first semiconductor optical amplifier SOA1, and a second semiconductor optical amplifier SOA2;

[0049] Wherein, the first semiconductor optical amplifier SOA1 and the second semiconductor optical amplifier SOA2 are bidirectionally connected to the first multimode interferometer MMI1 and the second multimode interferometer MMI2 respectively, and the carrier lifetimes of the first semiconductor optical amplifier SOA1 and the second semiconductor optical amplifier SOA2 are not equal, which are used to realize signal amplification and phase change;

[0050] The splitting coupler is used to divide the access signal into signal light and control light with unequal powers according to the splitting ratio, wherein the power of the signal light is less than that of the control light. The signal light is access to the first multimode interferometer MMI1, and the control light is access to the second multimode interferometer MMI2 after passing through the delay fiber;

[0051] The first output terminal a of the second multimode interferometer MMI2 is connected to the coupler in the HEM packet header extraction module for outputting the payload, and the second output terminal b is connected to the optical line terminal for outputting the optical packet header.

[0052] The HEM packet header extraction module is used for separating the optical packet header and the payload. There are some deficiencies in the existing all-optical technical solutions for separating the packet header and the payload: First, the switching ratio of the extracted header and payload is not very high. Second, timing devices such as FDLs are mostly used, or strict time alignment is required, so the implementation difficulty is relatively large. In addition, these solutions are mostly applicable to optical packets with a relatively low packet header rate, and for the case of a relatively high packet header rate, the performance of the system needs to be improved. In this architecture, the HEM adopts a new Mach-Zehnder type all-optical packet header and payload separation scheme, which is implemented based on SOA and multimode interferometer (MMI), and has the characteristics of compact structure, easy integration, high switching ratio, bit rate transparency, etc., and is suitable for variable-length and asynchronous packet switching requirements.

[0053] Such as Figure 3 It is a Mach-Zehnder type all-optical packet header and payload separation scheme. Among them, the splitting ratio of the coupler can be taken between 95:5 and 99:1. The multimode interferometer MMI1 is used as a splitter, and MMI2 is used as a coupler. The upper and lower phase shift arms respectively use two semiconductor optical amplifiers (SOA1, SOA2) with unequal carrier lifetimes to achieve signal amplification and phase change.

[0054] The optical packet is split by the splitter into two pulse streams with unequal powers (the illustrated power splitting ratio is 95:5). Among them, the part with lower power is used as the signal light (PS) and enters MMI1, and the part with higher power is used as the control light (CS) and enters MMI2 after passing through the FDL. After passing through MMI1, the PS is split into two parts with equal powers and respectively reaches SOA1 and SOA2. Since the two SOAs are symmetrically placed, the upper and lower two pulses reach the two SOAs simultaneously.

[0055] The packet headers of the two PS pulses first reach SOA1 and SOA2 (since the power of the signal light is very small, its influence on the gain saturation characteristic of the SOA can be ignored), so the packet headers of the upper and lower two signal lights PS experience unsaturated gain and phase shift. It can be considered that the two packet header pulses experience the same gain and equal phase shift.

[0056] After the packet header of the PS passes through the SOA, the upper and lower control lights CS reach SOA1 and SOA2 respectively. Due to their large power, the gain saturation of the two SOAs is caused. At this time, the payload part of the PS just enters the two SOAs. Therefore, the payload part of the PS experiences the saturated gain and phase shift generated by the CS. And because the carrier lifetimes of SOA1 and SOA2 are not equal, the payload parts of the upper and lower signal lights PS experience unequal saturated gain and phase shift. By selecting appropriate system parameters, the phase difference can reach 180°. Finally, after the two PSs interfere at MMI2, the packet header is output from port b, the payload is suppressed, the payload is output from port a, and the packet header is canceled by interference. In this way, the separation of the packet header and the payload is effectively realized.

[0057] As Figure 4 shown, the circulator is an important component of the optical access network for distributed edge data centers based on asynchronous optical packet switching. An existing architecture-based polarization-independent waveguide optical circulator is used, which consists of two MMIs, two Faraday rotators (FRs) and two half-wave plates (H). The optical circulator is used to realize the inter-port switching of signals. As shown in the figure, the downstream signal performs a 1→2 cycle, and the upstream signal performs a 2→3 cycle, and port 4 is left floating. The inter-port switching of signals can be realized as: 1→4, 4→3, 3→2, 2→1.

[0058] In summary, for the optical access network architecture for distributed edge data centers based on asynchronous optical packet switching proposed in the embodiments of the present invention, the process of data transmission is as follows:

[0059] For the downstream signal, the tasks arrive at each edge data center (EDC) of the optical line terminal OLT. One of a group of edge data centers in the OLT serves as a control unit. The control unit polls each task arriving at the EDC. After the polling is completed, it is sent to the TX. After passing through the 1 to 2 cycle of the EDFA and the circulator, the downstream packet enters the HEM to extract the packet header information. After the packet header information is extracted from port b, it is sent to the EDC of the OLT through the optical fiber for analysis. The payload enters the OXC and the delay optical fiber FDL through the 1 to 2 cycle of the circulator from port a and waits for the processing result of the control unit;

[0060] For the upstream signal, after the task arrives at the data access end ONU, it enters the HEM to extract the packet header information through the 2 to 1 cycle of the circulator. The packet header information is extracted from port b and sent to the EDC of the OLT. The payload reaches the OXC and the FDL through the coupler from port a and waits for the processing result of the control unit.

[0061] The optical access network architecture of a distributed edge data center based on asynchronous optical packet switching proposed according to the embodiments of the present invention can meet the application requirements of the access network. By adopting asynchronous optical packet switching technology and wavelength division multiplexing technology, it can achieve real-time and flexible random access for a large number of terminal user burst services, and improve the scalability of the system. For the uplink signal, when two or more signals from different groups are transmitted simultaneously at the same wavelength and conflict occurs, the use of a local conflict resolution solution can reduce the additional path delay and solve the problem of wavelength conflict when two or more ONUs generate uplink data simultaneously.

[0062] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or N embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0063] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "N" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

Claims

1. A distributed edge data center optical access network system based on asynchronous optical packet switching, characterized in that, Including: A data access end, which is used to access n×m uplink signals to be processed, divide the n×m uplink signals to be processed into m groups, modulate the n uplink signals to be processed in each group to a preset wavelength, and use a wavelength division multiplexer with multiple wavelengths to transmit the n uplink signals to be processed in each group; m + 1 HEM packet header extraction modules, where m HEM packet header extraction modules are connected to the data access end and the optical switching matrix, and the other HEM packet header extraction module is connected to the optical line terminal. The HEM packet header extraction module is used to separate the optical packet header and the payload from the accessed signal; HEM includes a beam splitter coupler, and the splitting ratio of the beam splitter coupler is between 95:5 and 99:1; The optical line terminal is used to amplify the accessed multiple downlink signals through an erbium-doped fiber amplifier and output them to the HEM packet header extraction module, and receive and analyze the optical packet header output by the HEM packet header extraction module to obtain the target address and priority information of each signal to be processed; A 1×m optical splitter, which is arranged between the optical switching matrix and the other HEM packet header extraction module; A delay fiber, which is used to cache the payload of each signal to be processed; The optical switching matrix is used to receive the payload of each signal to be processed sent by the HEM packet header extraction module and the target address and priority information of each signal to be processed sent by the optical line terminal, determine the switching state of the optical switching matrix according to the target address of each signal to be processed, and transmit the payload of each signal to be processed to the target address according to the priority information; during the process of transmitting the payloads of multiple signals to be processed to the target address, if at least two signals to be processed in different packet payloads are transmitted simultaneously at the same wavelength, the optical switching matrix is further used to determine the transmission order according to the priority information of the payload, and transmit the multiple payloads according to the transmission order, where the payloads waiting to be transmitted are cached in the delay fiber of the optical switching matrix.

2. The distributed edge data center optical access network system based on asynchronous optical packet switching according to claim 1, characterized in that, The HEM packet header extraction module includes: In the direction of the downlink signal transmission, a 1×2 coupler is added in front of the HEM, and an optical circulator is added behind the HEM. One path of the 1×2 coupler inputs the packet into the HEM in the direction of the downlink signal, and the payload output from the first port a of the HEM continues to go down through the optical circulator 1→2 and enters the subsequent module. The uplink signal enters the other path of the 1×2 coupler through the reverse direction of the optical circulator 2→3 for uplink signal transmission.

3. The distributed edge data center optical access network system based on asynchronous optical packet switching according to claim 2, characterized in that, HEM also includes: A first multimode interferometer MMI1, a second multimode interferometer MMI2, a first semiconductor optical amplifier SOA1, and a second semiconductor optical amplifier SOA2; Wherein, the first semiconductor optical amplifier SOA1 and the second semiconductor optical amplifier SOA2 are bidirectionally connected to the first multimode interferometer MMI1 and the second multimode interferometer MMI2 respectively, and the carrier lifetimes of the first semiconductor optical amplifier SOA1 and the second semiconductor optical amplifier SOA2 are not equal, which is used to realize signal amplification and phase change; The optical splitter coupler is used to divide the access signal into signal light and control light with unequal powers according to the splitting ratio, where the power of the signal light is less than that of the control light. The signal light is connected to the first multimode interferometer MMI1, and the control light is connected to the second multimode interferometer MMI2 after passing through the delay fiber; The first output terminal a of the second multimode interferometer MMI2 is connected to the coupler in the HEM packet header extraction module for outputting the payload, and the second output terminal b is connected to the optical line terminal for outputting the optical packet header.

4. The distributed edge data center optical access network system based on asynchronous optical packet switching according to claim 1, characterized in that, The optical line terminal includes: The edge data center is used to poll the received downlink signal to be processed; The optical transmitting module is used to receive and send the downlink signal to be processed.

5. The distributed edge data center optical access network system based on asynchronous optical packet switching according to claim 1, characterized in that, The delay time of the delay fiber of the optical switching matrix is an integer multiple of the receiving time of the optical line terminal.

6. The distributed edge data center optical access network system based on asynchronous optical packet switching according to claim 1, characterized in that, The delay fiber of the optical switching matrix is further used to discard the payload with the lowest priority when the number of groups of the payloads waiting for transmission is greater than the number of the delay fibers of the optical switching matrix, so that the number of the payloads waiting for transmission is equal to the number of the delay fibers of the optical switching matrix.

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