KR102124530B1 - Method, optical line terminal and apparatus for scheduling packet in ethernet passive optical network - Google Patents

Abstract

A method for scheduling a packet in an Ethernet-based passive optical network, an optical line terminal, and an apparatus thereof are provided. This method is a packet scheduling method performed in an optical line terminal (OLT) connected through a plurality of optical communication devices and a splitter in an Ethernet-based passive optical network. When a packet is received, a service is classified from the received packet. Extracting a service identifier for identifying, a subscriber identifier for distinguishing a subscriber, and a device identifier for distinguishing the optical communication device, using the service identifier, allocating a queue to the packet in a service unit, the subscriber identifier and And scheduling the queue by using one of the device identifiers individually, or by combining the subscriber identifier and the device identifier, and transmitting packets assigned to each queue according to a scheduling order.

Description

A method for scheduling packets in an Ethernet-based passive optical network, an optical line terminal, and a device thereof {METHOD, OPTICAL LINE TERMINAL AND APPARATUS FOR SCHEDULING PACKET IN ETHERNET PASSIVE OPTICAL NETWORK}

The present invention relates to a method for scheduling packets in an Ethernet-passive optical network (hereinafter, referred to as'EPON'), an optical line terminal, and an apparatus thereof.

Passive optical network (Passive optical network, hereinafter referred to as'PON') technology is based on time division multiplexing method PON (Time Division Multiplexing-PON, hereinafter referred to as'TDM-PON') and wavelength division multiplexing method It can be classified as a base PON (Wavelength Division Multiplexing-PON, hereinafter referred to as'WDM-PON'). EPON and GPON (Gigabit capable PON) are mainly used for TDM-PON, and multiple subscribers share the bandwidth through the time domain. Therefore, as the number of subscribers increases, the bandwidth available to subscribers is inversely reduced.

Conventionally, in 1G EPON (Ethernet-Passive optical network), when a packet is controlled by an optical line terminal (hereinafter referred to as'OLT'), a scheduling method based on a fixed priority is used. . In this scheduling method, high priority is given to services sensitive to the requirements of quality of services (hereinafter referred to as'QoS') such as delay and jitter, and to services less sensitive to QoS requirements (Best Effort). Assign a low priority. For example, suppose there are four fixed priority queues (1, 2, 3, 4), the first queue 1 has the highest priority, and the fourth queue 4 has the lowest priority. The scheduler preferentially serves the packets stacked in the first queue 1 with the highest priority, and after all the packets in the first queue 1 are serviced, the packets in the second queue 2, the next priority. This scheduling method has the disadvantage that the delay of packets belonging to the lowest priority is significantly increased, but it is generally used most in that it can accommodate services sensitive to QoS requirements.

However, if a large number of flows exist in the first queue 1 having the highest priority, the flows are assigned the same priority to each other, and thus service is provided through competition. Therefore, despite the priority traffic, the amount of packets serviced for each flow and the amount of delay experienced by each packet are different due to traffic collision caused by traffic with irregular attributes. It shows an irregular output curve like 1.

FIG. 1 shows a conventional EPON system. Referring to FIG. 1, the OLT 10 transmits a packet using a scheduling method based on the fixed priority described above. These packets are distributed through the splitter 20 to each optical communication device, that is, a plurality of ONTs and ONUs 30. Subscriber terminals are connected to each optical communication device 30. At this time, in the EPON communication section, N (up to 64) optical communication devices 30 are connected to one PON port of the OLT 10, and TDM communication is performed.

The OLT 10 classifies packets into a first class to which an IPTV service belongs, a second class to which a virtual private network (VPN), wireless data, etc. belong, and a third class to which an Internet service belongs, and according to the priority assigned to each class. To schedule the packet accordingly. In this method, it is difficult to differentiate QoS for each subscriber and service, and thus it is difficult to guarantee maximum or minimum bandwidth.

In addition, as described above, since the OLT 10 determines scheduling by assigning priority only by determining the service type of the packet, the output curve of the packet flow in the EPON communication section connected to the ONT or ONU with the OLT 10 is irregular. Indicates. That is, since certain service packets having the highest priority are preferentially transmitted, the delay of the relatively low priority packets increases until all of these packets are completely transmitted. While a subscriber using a specific service occupies the bandwidth, the bandwidth that other subscribers can use is limited, and thus, the change in the transmission speed of the EPON communication section is very large.

In 10G EPON, compared to 1G EPON, a relatively large amount of traffic is generated. When packet scheduling is performed to determine only the service type, such as 1G EPON, there is a problem that network instability increases.

It is to provide a method for hierarchical packet scheduling in an EPON system to be solved by the present invention, an optical line terminal and an apparatus for performing the same.

According to one feature of the present invention, the packet scheduling method is a packet scheduling method performed in an optical line terminal (OLT) connected through a plurality of optical communication devices and a splitter in an Ethernet-based passive optical network, and receives a packet. If it does, extracting a service identifier for classifying a service from the received packet, a subscriber identifier for classifying a subscriber, and a device identifier for classifying the optical communication device, at least one of the service identifier, the subscriber identifier and the device identifier Scheduling a packet using one, and transmitting a packet according to a scheduling order, wherein a packet scheduled based on the device identifier takes precedence over a packet scheduled based on the subscriber identifier, and the subscriber identifier Packets scheduled based on have priority over packets scheduled based on the service identifier.

The scheduling may include, by using the service identifier, allocating a queue in units of services to the packet, and individually using one of the subscriber identifier and the device identifier, or using the subscriber identifier and the device identifier. And combining to schedule the queue.

The allocating step may include determining a service priority of the packet through the service identifier, and allocating a queue corresponding to the priority of the service identifier among the plurality of queues in which priority is set to the packet. Can be.

The scheduling may include scheduling the service priority differently for each device identifier.

According to another feature of the invention, the optical line terminal is an optical line terminal (Optical Line Terminal, OLT) connected through a plurality of optical communication devices and a splitter in an Ethernet-based passive optical network, the plurality of optical communication devices are connected to at least one At least one of an optical communication port connected to a splitter, and at least one of a service identifier for classifying a service, a subscriber identifier for classifying a subscriber, and a device identifier for classifying the optical communication device, connected to the at least one optical communication port and a network. And a packet scheduler for performing packet scheduling of downlink packets and uplink packets using one, wherein the packet scheduler takes precedence over packets scheduled based on the device identifier and packets scheduled based on the device identifier. , A packet scheduled based on the subscriber identifier is scheduled to take precedence over a packet scheduled based on the service identifier.

The packet scheduler allocates a priority queue according to the service identifier to the downlink packet and the uplink packet, and can schedule the priority queue by using or combining the device identifier and the subscriber identifier individually. have.

The packet scheduler may set a different packet scheduling policy for each of the at least one optical communication port, identify an optical communication port based on the device identifier, and perform packet scheduling according to the scheduling policy set for the identified optical communication port.

According to another feature of the present invention, a packet scheduling apparatus includes a memory for storing a packet scheduling program, and at least one processor that executes the packet scheduling program, wherein the packet scheduling program distinguishes services extracted from packets. A service identifier for a subscriber, a subscriber identifier for distinguishing a subscriber, and a device identifier for distinguishing a plurality of optical communication devices are extracted, so that a packet scheduled based on the device identifier takes precedence over a packet scheduled based on the subscriber identifier, and the The packet scheduled based on the subscriber identifier performs hierarchical scheduling to override the packet scheduled based on the service identifier, and includes instructions for transmitting the packet according to the hierarchical scheduling order.

The packet scheduling program sets priorities according to service priority to a plurality of queues, allocates a queue corresponding to the priority of the service identifier to the packets, and packets having the same assigned queue are based on the device identifier. It may include instructions for first transmitting a packet according to a scheduling order and scheduling to transmit a packet according to a scheduling order based on the subscriber identifier when the transmission is completed.

The packet scheduling program sets priorities according to service priority to a plurality of queues, allocates a queue corresponding to the priority of the service identifier to the packets, and packets having the same assigned queue are based on the device identifier. It may include instructions for scheduling a packet to be transmitted first according to a scheduling order.

The packet scheduling program includes commands for setting priorities according to service priorities in a plurality of queues and allocating queues corresponding to the priority of the service identifiers to the packets, wherein the service priority is the device identifiers. Each can be set differently.

The packet scheduling device further includes a plurality of optical communication ports connected to a plurality of splitters to which the plurality of optical communication devices are connected, and the packet scheduling program sets different packet scheduling policies for each of the plurality of optical communication ports, and the device It may include instructions for identifying an optical communication port on which a packet is received or to output a packet based on an identifier, and performing packet scheduling according to a scheduling policy set for the identified optical communication port.

The packet scheduling program may include instructions for extracting the service identifier, the subscriber identifier, and the device identifier from at least one predefined header field of a packet.

According to an embodiment of the present invention, unlike the conventional in which the flow of packet flows in the EPON communication section in which the OLT and each subscriber are connected was irregular, by generating a regular packet flow flow, it is possible to improve the internet quality by enhancing network stability. And can provide a bandwidth guarantee service.

1 shows a conventional EPON system.
2 illustrates a configuration of an Ethernet Passive Optical Network (EPON) system according to an embodiment of the present invention.
3 shows a packet scheduling structure according to an embodiment of the present invention.
4 is a flowchart illustrating a packet scheduling method according to an embodiment of the present invention.
5 shows a simplified EPON system for describing the output state of a packet flow according to an embodiment of the present invention.
6 shows a packet scheduling structure according to another embodiment of the present invention.
7 is a flowchart illustrating a packet scheduling method according to another embodiment of the present invention.
8 shows a packet scheduling structure according to another embodiment of the present invention.
9 is a flowchart illustrating a packet scheduling method according to another embodiment of the present invention.
10 is a hardware block diagram of a packet scheduling apparatus according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present invention pertains can easily practice. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. In addition, in order to clearly describe the present invention in the drawings, parts irrelevant to the description are omitted, and like reference numerals are assigned to similar parts throughout the specification.

Throughout the specification, when a part “includes” a certain component, this means that other components may be further included rather than excluding other components unless specifically stated to the contrary.

In addition, terms such as “…unit”, “…group”, and “…module” described in the specification mean a unit that processes at least one function or operation, which may be implemented by hardware or software or a combination of hardware and software. Can be.

As used herein, "transfer or provide" may include not only direct transmission or provision, but also indirect transmission or provision through another device or by using a bypass path.

In this specification, expressions expressed in singular may be interpreted as singular or plural unless explicit expressions such as “one” or “single” are used.

FIG. 2 shows a configuration of an Ethernet Passive Optical Network (EPON) system according to an embodiment of the present invention, FIG. 3 shows a packet scheduling structure according to an embodiment of the present invention, and FIG. 4 shows an embodiment of the present invention A flowchart illustrating a packet scheduling method according to FIG. 5 is a simplified EPON system for describing an output state of a packet flow according to an embodiment of the present invention.

First, referring to FIG. 2, the EPON system is connected to the optical line terminal (Optical Line Terminal, hereinafter referred to as'OLT') 100 and a plurality of optical communication devices 200 in the form of a PON to transmit and receive Ethernet frames. . A plurality of optical communication devices 200 are connected to one OLT 100 through a splitter 300 in a point-to-multipoint structure. That is, the OLT 100 is located at the network-side endpoint, and the plurality of optical communication devices 200 are located at the subscriber-side endpoint.

The OLT 100 is a device that connects the backbone network and the subscriber network to each other, and may be located in a central office or a public office of a service provider.

The OLT 100 converts an Ethernet frame received from the network 400 into an optical signal, and transmits the optical signal to the plurality of optical communication devices 200 through the splitter 300. The OLT 100 converts the optical signal received from the splitter 300 into an Ethernet frame and transmits it to the network 400.

The network 400 may include a broadband network such as the Internet or Fiber To The x (FTTx) including FTTH (Fiber To The Home). The network 400 may be connected to a video/audio service server, an internet service server, an IPTV server, a virtual private network (VPN) server, and the like. The optical communication device 200 receives a corresponding service from each server.

The plurality of optical communication devices 200 converts the optical signals received from the splitter 300 into Ethernet frames and transmits them to a connected subscriber terminal (not shown). The plurality of optical communication devices 200 converts an Ethernet frame received from a connected subscriber terminal (not shown) into an optical signal, and transmits the optical signal to the OLT 100 through the splitter 300.

The plurality of optical communication devices 200 may provide an EPON subscriber interface and perform one-to-many (1:N) connection with a subscriber terminal (not shown). The plurality of optical communication devices 200 includes an optical network unit (ONU), an optical network terminal (ONT), and the like. ONU is a small outdoor/indoor optical communication device installed in the center of a residential subscriber dense area. ONU refers to equipment installed in the inlet of dense subscribers such as apartments to accommodate the condensing function of multiple subscribers, and implemented in the form of various layer 2 (L2) switching devices that accommodate existing xDSL or Ethernet subscriber lines before complete FTTH conversion. do.

ONT is an optical modem device that can be connected to a PC as a final optical termination device, meaning a single subscriber. ONT may be an optical modem device including a WiFi AP function. ONT is installed in the subscriber's premises to form a Fiber To The Home (FTTH) subscriber network. ONT is only distinguished from ONU in that it provides a means to directly connect service application terminal devices used by subscribers, and functions within EPON are the same as ONU, so ONU and ONT are collectively referred to as optical communication devices 200. Write.

The splitter 300 distributes the optical signals to the plurality of optical communication devices 200 and combines the respective optical signals received from the plurality of optical communication devices 200 and transmits them to the OLT 100.

In EPON, packet transmission is performed in the same unit as the existing Ethernet frame. The Ethernet frame is a variable length packet and is broadcast from the OLT 100 to a plurality of optical communication devices 200. The Ethernet frame includes a device identifier for distinguishing a plurality of optical communication devices 200 in a logical link identifier (hereinafter, referred to as'LLID') field located at the front of the frame separately from the MAC address. LLID is a value assigned through an auto-disconery process that is handled by the OLT 100 when the optical communication device 200 is first accessed to EPON, between the OLT 100 and the optical communication device 200. Used to distinguish logical links.

In the downlink (Downlink) channel, the OLT 100 broadcasts an Ethernet frame to all the optical communication devices 200. Each optical communication device 200 receives an Ethernet frame matching the LLID assigned to it, and discards the rest. At this time, the LLID may be set to be received by all other optical communication devices 200 except for the specific optical communication device 200, or by all optical communication devices 200 or by a specific multicast group.

In the uplink channel, all Ethernet frames transmitted by each optical communication device 200 are received by the OLT 100, and the OLT 100 is transmitted from any optical communication device 200 through the LLID included in the transmitted Ethernet frame. You can see if it is the Ethernet frame you sent.

The OLT 100 includes a fabric switch 110, a linecard 130, and a backplane 150.

The fabric switch 110 switches so that packets received from the network 400 are output to the PON port 131 connected to the corresponding optical communication device 200. The fabric switch 110 transmits packets received from the plurality of PON ports 131 to the network 400. In this case, packets having the same destination may be collected and transmitted to the network 400.

The line card 130 is connected to the fabric switch 110 through the backplane 150. The backplane 150 is electrical and mechanical equipment for connecting auxiliary substrates to the body substrate of the system.

The line card 130 is a printed circuit board (PCB) equipped with a plurality of (n) packet transmission/reception ports (PORT) 131 according to the EPON protocol, and may include up to 8 PON ports 131. .

N optical communication devices 200 are connected to one PON port 131, and time division multiplexing (hereinafter referred to as'TDM') communication is performed.

The line card 130 includes a packet scheduler 133, and the packet scheduler 133 controls packet transmission through hierarchical packet scheduling according to services, subscribers, and flows.

The packet scheduler 133 interprets the information stored in the header field of the packet to schedule each packet. That is, according to packet scheduling, the corresponding packet is output to the PON port 131, and the packet flowing from the PON port 131 is controlled to be output to the backplane 150.

At this time, the packet scheduler 133, unlike the conventional one, allocates packets input/output through one PON port 131 to a plurality of queues for each service, and hierarchical packets according to subscribers and flows for the plurality of queues Perform scheduling.

That is, the packet scheduler 133 differentially provides QoS for each service, subscriber, and flow. The packet scheduler 133 may provide services such as maximum/minimum bandwidth guarantee and latency maintenance as well as packet scheduling according to priority based on differentiated services.

Here, the packet scheduler 133 is a packet of Class of Service (CoS), Differentiated Service Code Point (DSCP), IP Precedence field, Protocol field, Source (Source, Src) MAC (Media Access Control) ) Service individually or in combination with the priority values included in the address field, destination (Dst) MAC address field, Src IP address field, Dst IP address field, Src Port address field, and Dst Port address field. To distinguish. Here, the CoS, DSCP, and IP Precedence fields may be located in the header information of the packet.

For example, the IPTV service may be set with the highest priority, the next priority such as VPN and wireless data service, and the Internet service with the lowest priority.

In addition, the packet scheduler 133 distinguishes subscribers using a virtual LAN ID (VID). VID is an identifier that identifies a virtual LAN (VLAN) of a predetermined group to which the optical communication device 200 belongs, and is currently composed of 4096 pieces. VIDs are allocated differently for each user network interface (UNI) of the optical communication device 200.

Also, the packet scheduler 133 distinguishes the optical communication device 200 and identifies the packet flow using the LLID, as described above.

A plurality of (n) cues are set for each PON port 131. The plurality of queues is a storage for buffering packets temporarily before the packet scheduler 133 outputs them to the PON port 131 or the backplane 150. It can be seen that the plurality of queues does not have a memory space for storing the actual packets, but continuously has pointer information indicating the location of the memo where the packets are waiting.

At this time, a plurality of queues may have a priority set. For example, the priority of a plurality of queues may be assigned as high as Queue 1> Queue 2> Queue 3> Queue 4.

According to the hierarchical packet scheduling structure of FIG. 3, at level (1), the packet scheduler 133 allocates packets to a corresponding queue according to a service identifier. At level 2, the packet scheduler 133 determines the order of packets to be first transmitted based on UNI, that is, VID, according to a preset policy for packets assigned to the same queue. At level 3, the packet scheduler 133 determines the order of packets to be transmitted first based on the LLID according to a preset policy for packets assigned to the same queue.

For example, when packets of a, b, and c are received, and if a, b, and c are all assigned to queue 1, the high priority packets (a, b) are selected based on the VID, and the VID When the priorities are the same, the highest priority packet (b) is selected based on the LLID. The packet scheduler 133 outputs packets in order of high priority.

Referring to FIG. 4, a packet scheduling process of the packet scheduler 133 is illustrated. When the packet is received (S101), the packet scheduler 133 extracts a service identifier, VID, and LLID from the packet header field (S103). .

The packet scheduler 133 performs queue mapping according to the extracted service identifier (S103) (S105). That is, the priority is confirmed through the service identifier, and a packet is allocated to the queue having the confirmed priority. Referring to FIG. 3, a queue group consisting of queue 1, queue 2, queue 3, and queue 4 is set to have a higher priority than a queue group consisting of queue 5, queue 6, queue 7, and queue 8. Therefore, the packet assigned to queue 1 has priority over the packet assigned to queue 5 when transmitting packets.

The packet scheduler 133 first outputs a packet having a high LLID priority according to a policy among packets within the same priority (S107). For example, even when the packet flow is concentrated to the optical communication device 1, even if it is a specific service packet, the LLID priority of the optical communication device 1 may be set relatively low compared to other optical communication devices for load balancing of the optical communication device 1.

In step S107, the packet scheduler 133 determines whether all packet transmissions are completed according to the priority (S109), and when all are transmitted, outputs a packet having a high VID priority according to the policy (S111).

At this time, the policy is set to provide a bandwidth guarantee service based on the VLAN band.

In step S111, the packet scheduler 133 determines whether all packet transmissions are completed according to the priority (S113), and when all are transmitted, transmits a packet according to the service priority (S115). At this time, after outputting the packets preferentially according to the LLID and VID priorities, it may be a task of transmitting all remaining packets in the corresponding queue.

Then, the packet scheduler 133 repeats steps S107 to S115 for packets allocated to the next priority queue.

As described above, the packet scheduler 133 may schedule the packet flow by combining service, subscriber, and flow, thereby uniformly (or uniformly) controlling the output flow of the packet flow in the EPON communication section.

6 shows a packet scheduling structure according to another embodiment of the present invention, and FIG. 7 is a flowchart illustrating a packet scheduling method according to another embodiment of the present invention.

This embodiment corresponds to an embodiment in which the embodiments of FIGS. 2 to 5 are modified as a packet scheduling method when the EPON system is implemented only for subscribers. At this time, the optical communication device (200 in FIG. 2) is a subscriber-only device.

Referring to FIG. 6, the packet scheduling structure is operated in two layers, and when compared with FIG. 3, there is no level 2 distinguishing subscribers. A packet scheduling method according to the packet scheduling structure is illustrated in FIG. 7.

Referring to FIG. 7, when a packet is received (S201 ), the packet scheduler (133 of FIG. 2) extracts a service identifier and an LLID from the packet header field (S203 ).

The packet scheduler 133 performs queue mapping according to the extracted service identifier (S203) (S205). That is, the priority is confirmed through the service identifier, and a packet is allocated to the queue having the confirmed priority.

The packet scheduler 133 first outputs a packet having a high LLID priority according to a policy among packets within the same priority (S207).

In step S207, the packet scheduler 133 determines whether all packet transmissions are completed according to priority (S209), and when all are transmitted, transmits a packet according to the service priority (S211). At this time, after outputting the packet preferentially according to the LLID priority, it may be a task of transmitting all remaining packets in the corresponding queue.

Then, the packet scheduler 133 repeats steps S207 to S211 for packets allocated to the next priority queue.

As described above, the packet scheduler 133 may schedule packets by combining services and flows for dedicated subscribers.

8 shows a packet scheduling structure according to another embodiment of the present invention, and FIG. 9 is a flowchart showing a packet scheduling method according to another embodiment of the present invention.

This embodiment is a virtualized packet scheduling method, and corresponds to an embodiment in which the embodiments of FIGS. 6 and 7 are modified. This embodiment corresponds to an embodiment in which the embodiments of FIGS. 2 to 5 are modified as a packet scheduling method when the EPON system is implemented only for subscribers. At this time, the optical communication device (200 in FIG. 2) is a subscriber-only device.

Referring to FIG. 8, the packet scheduling structure is operated in two layers, and service policies for each LLID are different. 8 is a virtual queue structure method for actively controlling exceptional traffic, and the LLID value is allocated as 101 to 105 as an example, but is not limited thereto, and may be variously allocated and changed after being allocated according to policy It may be.

A packet scheduling method according to the packet scheduling structure is shown in FIG. 9.

Referring to FIG. 9, when a packet is received (S301), the packet scheduler (133 of FIG. 2) extracts a service identifier and an LLID from the packet header field (S303).

The packet scheduler 133 performs queue mapping according to the extracted service identifier (S303) (S305). That is, the priority is confirmed through the service identifier, and a packet is allocated to the queue having the confirmed priority.

The packet scheduler 133 checks service policies set differently for each LLID, and schedules to output packets having high priority according to the checked service policy (S307). For example, in the case of LLID1, the priority of a downstream broadcast (Bcast), downstream multicast (Mcast), or upstream (Bstream) packet is set as the highest priority, whereas in the case of LLID2 , Priority of an upstream broadcast packet is set as the highest priority. In the case of LLID3, the priority of the upstream broadcast packet is set as the highest priority, and in the case of LLID4, the priority of the packet is determined according to the queue priority allocated according to the service identifier. In the case of LLID5, the priority of the reserved packet is set as the highest priority.

Meanwhile, FIG. 10 is a hardware block diagram of a packet scheduling apparatus according to an embodiment of the present invention, and shows a hardware configuration of the packet scheduler 133 of the optical line terminal 100 described with reference to FIGS. 1 to 9.

Referring to FIG. 10, the packet scheduling device 500 includes a communication device 501, a memory 503, and at least one processor 505.

The communication device 501 is connected to at least one processor 507 and includes an interface for transmitting/receiving packets or input/output packets. The memory 503 is connected to at least one processor 507 and stores a packet scheduling program including instructions to execute a configuration and/or method according to the embodiments described with reference to FIGS. 1 to 10. .

The embodiment of the present invention described above is not implemented only through an apparatus and method, and may be implemented through a program that realizes a function corresponding to the configuration of the embodiment of the present invention or a recording medium in which the program is recorded.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

Claims (13)

A packet scheduling method performed in an optical line terminal (OLT) connected through a plurality of optical communication devices and a splitter in an Ethernet-based passive optical network,
When receiving a packet, extracting a service identifier for classifying a service, a subscriber identifier for classifying a subscriber, and a device identifier for classifying the optical communication device from the received packet,
Checking the service priority of the packet through the service identifier,
Allocating a queue corresponding to the priority of the service identifier among a plurality of queues with priority, to the packet
Scheduling the priority of packets stored in a queue having the same service priority by using one of the subscriber identifier and the device identifier individually, or combining the subscriber identifier and the device identifier, and
And transmitting a packet according to the scheduled priority,
The scheduling step,
A packet having a higher priority is determined based on the subscriber identifier for a packet allocated to a queue having the same priority as the service identifier, and a priority is assigned based on the device identifier for a packet having the same priority as the subscriber identifier. Determine a high packet, or
A packet scheduling method for determining a packet having a higher priority based on the subscriber identifier or the device identifier for a packet allocated to a queue having the same priority as the service identifier. delete delete In claim 1,
The scheduling step,
A packet scheduling method for scheduling the service priority differently according to a service policy set differently for each device identifier. As an optical line terminal (OLT) connected through a plurality of optical communication devices and a splitter in an Ethernet-based passive optical network,
At least one optical communication port connected to at least one splitter to which the plurality of optical communication devices are connected, and
Downlink packet and uplink packet connected to the at least one optical communication port and network, using at least one of a service identifier for classifying a service, a subscriber identifier for classifying a subscriber, and a device identifier for classifying the optical communication device It includes a packet scheduler to perform the packet scheduling of,
The packet scheduler,
A packet having a higher priority is determined based on the subscriber identifier for a packet assigned to a queue having the same priority as the service identifier, and a priority is assigned based on the device identifier for a packet having the same priority as the subscriber identifier. Determine a high packet, or
An optical line terminal that determines a packet having a higher priority based on the subscriber identifier or the device identifier for a packet allocated to a queue having the same priority as the service identifier. delete In claim 5,
The packet scheduler,
An optical line terminal that sets a different packet scheduling policy for each of the at least one optical communication port, identifies an optical communication port based on the device identifier, and performs packet scheduling according to the scheduling policy set for the identified optical communication port. Memory that stores the packet scheduling program, and
And at least one processor that executes the packet scheduling program,
The packet scheduling program,
A service identifier for classifying the service extracted from the packet, a subscriber identifier for classifying the subscriber, and a device identifier for classifying a plurality of optical communication devices,
Priority according to service priority is set in a plurality of queues, a queue corresponding to the priority of the service identifier is assigned to the packet, and packets scheduled based on the device identifier are scheduled based on the subscriber identifier. Instructions to prioritize a packet, and to perform a hierarchical scheduling to prioritize a packet scheduled based on the subscriber identifier to a packet scheduled based on the service identifier, and to transmit packets according to the hierarchical scheduling order Including,
The hierarchical scheduling,
Packets having the same assigned queue are first transmitted according to the scheduling order based on the device identifier, and when the transmission is completed, the packet is transmitted according to the scheduling order based on the subscriber identifier, and when the transmission is completed, the service identifier is transmitted to the service identifier. Packets are transmitted according to a scheduling sequence based on
Packet scheduling in which the assigned queue transmits packets of the same packets according to the scheduling sequence based on the device identifier or the subscriber identifier, and then transmits the packets according to the scheduling sequence based on the service identifier when transmission is completed. Device. delete delete In claim 8,
The packet scheduling program,
Set a priority according to a service priority in a plurality of queues, and include instructions for assigning a queue corresponding to the priority of the service identifier to the packet,
The service priority is set differently for each device identifier, a packet scheduling device. In claim 8,
Further comprising a plurality of optical communication ports connected to a plurality of splitters connected to the plurality of optical communication devices,
The packet scheduling program,
Set a different packet scheduling policy for each of the plurality of optical communication ports,
A packet scheduling apparatus comprising instructions for identifying an optical communication port on which a packet is received or to output a packet based on the device identifier, and performing packet scheduling according to a scheduling policy set for the identified optical communication port. In claim 8,
The packet scheduling program,
And instructions for extracting the service identifier, the subscriber identifier and the device identifier from at least one predefined header field of a packet.

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