CN104639467B

CN104639467B - A kind of bandwidth allocation methods, device and optical network system

Info

Publication number: CN104639467B
Application number: CN201510100132.6A
Authority: CN
Inventors: 张民; 杨洋; 蒋俊; 刘晶丹; 张治国
Original assignee: Beijing University of Posts and Telecommunications
Current assignee: Beijing University of Posts and Telecommunications
Priority date: 2015-03-06
Filing date: 2015-03-06
Publication date: 2017-10-03
Anticipated expiration: 2035-03-06
Also published as: CN104639467A

Abstract

The embodiment of the invention discloses a kind of bandwidth allocation methods, device and optical network system, it is related to wireless communication field, wherein, above-mentioned bandwidth allocation methods are applied to the ONT Optical Network Terminal OLT in optical network system, including：Receive the bandwidth requirement information of objective community in current period；According to bandwidth requirement information, according to default algorithm, the ONU included from default more modulation form in selection target group modulation format；According to selected modulation format and band width in physical, available bandwidth is determined；It is each ONU distribution bandwidth in objective community according to the bandwidth demand of objective community and identified available bandwidth；According to above-mentioned by the bandwidth that each ONU is distributed in objective community, the traffic assignments subcarrier and time slot of the different grades of service for being each ONU.Using scheme provided in an embodiment of the present invention, it disclosure satisfy that the ONU of each group is directed to the bandwidth demand of different business, improve Consumer's Experience.

Description

Bandwidth allocation method and device and optical network system

Technical Field

The present invention relates to the field of wireless communications, and in particular, to a bandwidth allocation method and apparatus, and an optical network system.

Background

With the rapid development of wireless communication technology, the customer population is larger and larger, and the services provided by service providers for customers are richer and richer. However, since the service contents of the services are different, the bandwidth requirements of the services are also different.

In the prior art, when performing wireless communication, because factors such as bandwidth requirements of an ONU (Optical Network unit) are not considered when an OLT (Optical Line Terminal) selects a modulation format for the ONU, when allocating a bandwidth to the ONU based on an available bandwidth determined by the modulation format selected by the OLT, the bandwidth requirements of the ONU are not necessarily met, and especially, when a current service data sent by the ONU to the OLT has a large demand for the bandwidth, a situation of insufficient bandwidth may exist, which further affects user experience.

Disclosure of Invention

The embodiment of the invention discloses a bandwidth allocation method, a bandwidth allocation device and an optical network system, which are used for meeting the bandwidth requirements of each ONU for different services and improving the user experience.

In order to achieve the above object, an embodiment of the present invention discloses a bandwidth allocation method, which is applied to an optical network terminal OLT in an optical network system, where the optical network system includes: the method comprises the steps that an OLT and a first preset number of communities are provided, each community comprises at least one optical network unit ONU, and the method comprises the following steps:

receiving bandwidth demand information of a target community in a current period;

selecting a modulation format of the ONU contained in the target community from multiple preset modulation formats according to the bandwidth demand information and a preset algorithm;

determining an available bandwidth according to the selected modulation format and the physical bandwidth;

according to the bandwidth requirement of the target community and the determined available bandwidth, allocating bandwidth to each ONU in the target community;

and allocating sub-carriers and time slots for the services of different service levels of each ONU according to the bandwidth allocated to each ONU in the target community.

In a specific implementation manner of the present invention, the selecting, according to the bandwidth requirement information and according to a preset algorithm, a modulation format of an ONU included in the target community from multiple preset modulation formats includes:

respectively calculating cost factors corresponding to the ONUs contained in the target community under each preset modulation format according to the bandwidth demand information, wherein the cost factors are used for representing estimated cost values of the ONUs contained in the target community when the ONUs are modulated by the current modulation format;

and selecting the preset modulation format corresponding to the minimum cost factor as the modulation format of the ONU contained in the target community.

In a specific implementation manner of the present invention, the calculating, according to the bandwidth requirement information and according to a preset algorithm, cost factors corresponding to ONUs included in the target community under each preset modulation format respectively includes:

respectively calculating cost factors corresponding to the ONUs contained in the target community under each preset modulation format according to the bandwidth demand information and the following expressions,

cost factor

Wherein i represents a cycle number of a current cycle, j represents an identifier of a preset modulation format, and l represents a distance between the OLT and the target community,a delay weight coefficient representing the ith period,represents the power weight coefficient of the ith period,

rtv_τ_i,lfor a first class of service CoS in the i-1 th cycle₀Time delay of (1) and CoS in the first i-1 cycles₀Rtv _ b, the ratio between the average time delays of_i,lCoS of all ONU in bandwidth requirement of ith period of the target community₀Sum of bandwidth requirements and CoS in the first i cycles₀Rtv _ p, the ratio between the average bandwidth requirements_i,lThe ratio of the required received power of the i-1 th period to the average received power of the first i-1 periods at the preset error rate,

τ_j,lrepresents the CoS for the modulation format denoted j at the distance l between the OLT and the target community₀Time delay of p_j,lIs represented between the OLT and the targetThe required received power under the preset error rate for the modulation format marked as j under the distance l between the communities,

f () is about τ_j,lG () as to p_j,lThe mapping function of (2).

In one particular implementation of the invention,

wherein n represents the number of available modulation formats of the target population at a distance l between the OLT and the target population.

In a specific implementation manner of the present invention, the allocating subcarriers and timeslots to the traffic of different service levels of each ONU according to the bandwidth allocated to each ONU in the target community includes:

according to the bandwidth allocated to each ONU in the target community, sub-carriers and time slots are allocated to the services of different service levels of each ONU in the following manner:

according to the CoS in the next period in the bandwidth demand information₀Traffic of (1), CoS of target ONU₀The service allocates subcarriers and time slots;

according to the estimated CoS recorded in the report packet of the current period₁The traffic volume of the service is CoS transmitted by the target ONU in the idle time of the next period₁Traffic allocation subcarriers and timeslots, where estimated CoS₁The traffic volume of the service is: according to CoS generated in the interval of every two adjacent report packets in the period of the first preset number of periods₁The service volume of the service is calculated;

according to the residual CoS recorded in the report packet of the current period₁Traffic volume of service, CoS transmitted in current period for target ONU₁Service distributionSub-carriers and time slots, wherein the remaining CoS₁The service volume of the service is the CoS cached by the target ONU in the current period₁Total traffic of traffic — Pre-allocated CoS recorded in last cycle's gate packet₁CoS to be sent in a sub-period₁Traffic of a service, one cycle includes: CoS₁/CoS₂Sub-period, CoS₀Subcycle and Pre-allocated CoS₁A sub-period;

according to class three class of service class CoS in current period₂Traffic of (1), CoS of target ONU₂Traffic allocates subcarriers and time slots.

In a specific implementation manner of the present invention, the CoS generated in every two adjacent report packet intervals in the first preset number of cycles is used as the reference₁The service traffic, the calculated traffic, includes:

according to CoS generated in the interval of every two adjacent report packets in the period of the first preset number of periods₁The service volume of the service, calculating the above-mentioned each CoS₁Traffic volume obtained from an average of traffic volumes of the services.

In order to achieve the above object, an embodiment of the present invention discloses a bandwidth allocation apparatus, which is applied to an optical network terminal OLT in an optical network system, where the optical network system includes: OLT and a first preset number of communities, each community including at least one optical network unit ONU, the device comprising:

the bandwidth demand information receiving module is used for receiving bandwidth demand information of the target community in the current period;

the modulation format selection module is used for selecting the modulation format of the ONU contained in the target community from multiple preset modulation formats according to the bandwidth demand information and a preset algorithm;

an available bandwidth determining module, configured to determine an available bandwidth according to the selected modulation format and the physical bandwidth;

the bandwidth allocation module is used for allocating bandwidth to each ONU in the target community according to the bandwidth requirement of the target community and the determined available bandwidth;

and the subcarrier and time slot allocation module is used for allocating subcarriers and time slots to the services of different service levels of each ONU according to the bandwidth allocated to each ONU in the target community.

In order to achieve the above object, an embodiment of the present invention discloses an optical network system, which includes:

the OLT, the optical cable equipment ODN and a fourth preset number of communities;

the ODN comprises a plurality of optical splitters, wherein the number of the optical splitters is equal to the number of the communities;

the OLT is in communication connection with each community through each optical splitter in the ODN;

each community comprises at least one sub-community;

each subgroup comprises an active remote node ARN and at least one ONU which is respectively connected with the active remote node ARN in a communication way;

ARNs contained in each subgroup in the same community are in communication connection with the OLT through the same optical splitter; each subgroup in the same community communicates with the OLT through subcarriers with the same wavelength;

the OLT receives bandwidth demand information of a target community in a current period, selects a modulation format of an ONU (optical network unit) contained in the target community from multiple preset modulation formats according to the bandwidth demand information and a preset algorithm, determines an available bandwidth according to the selected modulation format and a physical bandwidth, allocates bandwidth to each ONU in the target community according to the bandwidth demand of the target community and the determined available bandwidth, and allocates subcarrier and time slot to services of different service levels of each ONU according to the bandwidth allocated to each ONU in the target community;

and each ONU sends the services with different service levels to the OLT according to the bandwidth allocated to the OLT by the OLT.

In a specific implementation of the present invention, a cycle includes: CoS₁/CoS₂Sub-period, CoS₀Subcycle and Pre-allocated CoS₁A sub-period;

each ONU is specifically used for CoS₁/CoS₂In a sub-period, sending its corresponding CoS to the OLT₁/CoS₂A service;

individual ONU in CoS₀In a sub-period, sending its corresponding CoS to the OLT₀Service, wherein each ONU transmits a CoS₀The service is as follows: CoS in the next cycle₀The service of (2);

pre-allocating CoS for each ONU₁And in the sub-period, sending corresponding services to the OLT, wherein the services sent by each ONU are as follows: estimated CoS₁The estimated CoS is the minimum value between the service volume of the service and the service volume of the service which can be sent by the fifth preset number of subcarriers₁The traffic volume of the service is: according to CoS generated in the interval of adjacent report packets in the first sixth preset number of periods₁And the service volume of the service is calculated.

In a specific implementation manner of the present invention, each ONU is further configured to detect a CoS for caching₀If the space of the service is full, if the space is used for caching the CoS₀Detecting for caching CoS if the space of the service is full₂If the space of the service is full, if the space is used for caching the CoS₂If the space of the service is not full, the CoS is used₀Storing traffic to for caching CoS₂The space of the service.

As can be seen from the above, in the scheme provided in the embodiment of the present invention, the OLT selects a modulation format for the ONUs included in the target community according to the received bandwidth demand information of the target community in the current period, further determines an available bandwidth, and allocates a bandwidth to each ONU in the target community according to the determined available bandwidth. Compared with the prior art, in the scheme provided by the embodiment of the invention, when the bandwidth is allocated to each ONU in the target community, the bandwidth requirement information of the target community is considered, and the same better modulation format is selected for each ONU in the community aiming at different bandwidth requirements of the target community, so that different available bandwidths are obtained, the bandwidth requirements of the ONUs of each community under different conditions are met, and the user experience is improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic structural diagram of an optical network system in the prior art;

fig. 2 is a schematic structural diagram of an optical network system according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of an optical network system according to an embodiment of the present invention;

fig. 4 is a schematic flow chart of a bandwidth allocation method according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a bandwidth distribution apparatus according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As is well known to those skilled in the art, for various optical network systems, there is usually a phenomenon of uneven distribution of geographic locations of users, and if the distance between users is long, it is not guaranteed that users within a certain distance range access to the same optical network system.

The optical network system provided by the embodiment of the present invention is described below by comparing with the optical network system in the prior art.

Fig. 1 is a schematic diagram of a specific structure of an optical network system in the prior art, where the optical network system includes: OLT101, ODN (Optical Distribution Network) 102, and community 103.

The community 103 comprises a plurality of ONUs, the number of the ONUs can be determined according to actual conditions, the ODN 102 comprises a plurality of optical splitters, the OLT101 is in communication connection with each ONU in the community 103 through each optical splitter in the ODN 102, and specifically, each ONU is in communication connection with a preset optical splitter in the ODN 102 through an optical fiber.

In general, the number of optical fibers required for the respective ONUs to be communicatively connected to the ODN 102 is equal to the number of ONUs included in the community 103, and thus, as the number of ONUs in the community 103 increases, the number of required optical fibers increases, and thus the cost for constructing an optical network system also increases greatly.

In addition, the OLT101 allocates bandwidth to each ONU in the community 103 and sends bandwidth allocation information to the corresponding ONU, so that each ONU sends traffic of different service levels to the OLT101 according to the bandwidth allocated by the OLT 101.

In summary, it is easy to know by those skilled in the art that the optical network system only includes a community, and the service range of each ONU in the community is generally small, so the service range of the optical network system is generally small, and when the system is applied, if the communication quality of users in a large range is to be ensured, the system can only be implemented by constructing a plurality of optical network systems.

To solve the above-mentioned problems in the existing optical network system, an embodiment of the present invention provides a novel optical network system, referring to fig. 2, where fig. 2 is a schematic structural diagram of an optical network system provided in an embodiment of the present invention, and the optical network system includes:

the OLT201, the ODN 202, and a fourth preset number of communities: community 1, community 2, … …, community (N-1), community N.

It should be noted that each community included in this embodiment may correspond to different service ranges, that is, it can be understood that: the distances between the respective communities and the OLT are different, and it can be further understood that the distances between the ONUs included in each community and the OLT are equal or approximately equal, and the distances between the ONUs included in different communities and the OLT are different.

The ODN 202 includes a plurality of optical splitters, the number of the optical splitters is equal to the number of the colonies, that is: the number of optical splitters is equal to a fourth predetermined number.

The OLT201 is respectively connected to each community through each optical splitter in the ODN 202 in a communication manner, and each community in the system may correspond to different service ranges, which can be simply understood as: each community can provide communication services for users within different ranges of distance from the OLT201, for example, a certain community can provide communication services for users within 10km of distance from the OLT201, a certain community can provide communication services for users within 40km of distance from the OLT201, and so on. Because the service ranges corresponding to the communities are different, the service ranges of the communities and the number of the communities in the optical network system can be set by considering the distribution characteristics of users and combining with actual conditions when the optical network system is constructed. For example, in practical applications, when an optical network system is required to provide communication services for users in a wide range, 4, 8, or even 10 communities may be set, and a different service range may be set for each community, for example: the method provides communication service for users within 10km of the OLT201, provides communication service for users within 40km of the OLT201, provides communication service for users within 100km of the OLT201, and the like, so that users with longer distance of the OLT201 can also successfully communicate through the optical network system without constructing a plurality of optical network systems, and construction cost can be greatly saved.

In addition, the service scope corresponding to each community is generally large, in the optical network system provided in this embodiment, each community may include at least one sub-community, where the number of sub-communities included in each community may be equal or unequal, which is not limited in this application, for example, the number of sub-communities included in one community may be 4, 5, 8, and the like.

Each subgroup corresponds to a further refined service scope on the basis of the service scope of its corresponding community. Assuming that a community comprises 4 sub-communities capable of providing communication services for users within a distance range of 10km from OLT201, the 4 sub-communities comprise 4 sub-communities capable of providing communication services for users within a distance range of 3km from OLT201, for users within a distance range of [3km, 5km ] from OLT201, for users within a distance range of [5km, 8km ] from OLT201, and for users within a distance range of [8km, 10km ] from OLT 201. The present application is described by way of example only, and the specific implementation is not limited to the above case.

In addition, when dividing the sub-groups, the service range is considered, and the distances between the ONUs can be considered, and when the distances between the ONUs and the OLT are equal or approximately equal, and the distances between the ONUs are far, the ONUs can be divided into different sub-groups.

Each of the sub-communities may include an ARN (Active Remote Node) and at least one ONU in communication connection therewith, where the number of ONUs included in each sub-community may be determined according to specific situations, for example, according to a distribution situation of a user, an activity level of the user, and the like, and the number of ONUs included in each sub-community may be equal or unequal, which is not limited in this application. For example, one sub-community may include one ARN and 7 ONUs respectively communicatively connected to the ARN: ONU (optical network Unit)₁、ONU₂、……、ONU₇。

The ARNs contained in each subgroup in the same community are in communication connection with the OLT201 through the same optical splitter; each subgroup in the same cluster communicates with OLT201 via subcarriers of the same wavelength.

Specifically, the ARN included in each subgroup may be in communication connection with one optical splitter through an optical fiber, and after the OLT201 sends information to the ARN through the optical fiber via the optical splitter, the ARN forwards the received information to each ONU corresponding thereto. Here, only one optical fiber is needed between one ARN and one optical splitter, and further it can be understood that: compared with the prior art that only one optical fiber is needed between each ONU and one optical splitter, the system can greatly save the number of the optical fibers, meanwhile, the transmission loss can be reduced in the transmission process due to the reduction of the number of the optical fibers, and the effect of reducing the transmission loss of the system is more obvious particularly for long-distance transmission.

In the above optical network system, the OLT201 may receive bandwidth requirement information sent by a certain community, and allocate bandwidth to each ONU in the community according to the received bandwidth requirement information.

Specifically, the OLT201 receives bandwidth requirement information of a target community in a current period, selects a modulation format of an ONU included in the target community from multiple preset modulation formats according to the bandwidth requirement information and a preset algorithm, determines an available bandwidth according to the selected modulation format and a physical bandwidth, allocates a bandwidth to each ONU in the target community according to the bandwidth requirement of the target community and the determined available bandwidth, and allocates subcarrier and timeslot to services of different service levels of each ONU according to the bandwidth allocated to each ONU in the target community.

In the system, after the OLT201 allocates bandwidth to each ONU in the community, the bandwidth allocation condition is sent to the corresponding ONU, and each ONU sends services of different service levels to the OLT201 according to the bandwidth allocated to it by the OLT 201.

In addition, in the process of allocating bandwidth to each ONU, the OLT201 selects a modulation format for the ONUs included in the target community according to the bandwidth requirement information of the target community in the current period, instead of using an agreed modulation format, so that the OLT201 needs to send the selected modulation format information to the corresponding ONUs. In a specific implementation, the OLT201 may identify, in the gate packet of the current period, the modulation format of the ONU included in the target community by a third preset number of bytes, for example, identify the modulation format of the ONU included in the target community by 1 byte, so that the ONU included in the target community obtains the modulation format by parsing the received gate packet of the current period. Meanwhile, the ONU included in the target community may add a third preset number of bytes to the data packet of the current period to identify the modulation format of the ONU included in the target community, so that the receiving end of the OLT can obtain the modulation format by analyzing the received data packet of the current period to perform data demodulation.

Specifically, when the OLT201 selects a modulation format of an ONU included in the target community from multiple preset modulation formats according to the bandwidth requirement information and according to a preset algorithm, the OLT201 may first calculate cost factors corresponding to the ONUs included in the target community under each preset modulation format according to the bandwidth requirement information, and then select the preset modulation format corresponding to the minimum cost factor as the modulation format of the ONUs included in the target community. The cost factor is used for representing an estimated cost value of the ONU included in the target community when the ONU adopts the current modulation format for modulation.

In a specific implementation manner of the present invention, when the OLT201 calculates the cost factors corresponding to the ONUs included in the target community under each preset modulation format according to the bandwidth requirement information and the preset algorithm, the cost factors corresponding to the ONUs included in the target community under each preset modulation format may be calculated according to the bandwidth requirement information and the following expression,

cost factor

Wherein i represents the cycle number of the current cycle, j represents the identifier of the preset modulation format, l represents the distance between the OLT201 and the target community,a delay weight coefficient representing the ith period,represents the power weight coefficient of the ith period,

rtv_τ_i,lfor a first class of service CoS in the i-1 th cycle₀Time delay of (1) and the first iPeriodic CoS₀Rtv _ b, the ratio between the average time delays of_i,lCoS of all ONUs in bandwidth requirement of ith period of target community₀Sum of bandwidth requirements and CoS in the first i cycles₀Rtv _ p, the ratio between the average bandwidth requirements_i,lThe ratio of the required received power of the i-1 th period to the average received power of the first i-1 periods at the preset error rate,

τ_j,lindicates that at a distance l between the OLT201 and the target community, the CoS is the modulation format denoted j₀Time delay of p_j,lIndicating the required received power at a preset error rate for the modulation format identified as j at the distance l between the OLT201 and the target community,

f () is about τ_j,lG () as to p_j,lThe mapping function of (2).

The predetermined bit error rate may be a value predetermined according to a specific application.

In particular, the method comprises the following steps of,

where n represents the number of available modulation formats of the target population at the distance l between the OLT and the target population.

In a preferred embodiment of the present invention, when the OLT201 allocates subcarriers and timeslots to the traffic of different service levels of each ONU in the target community according to the bandwidth allocated to each ONU in the target community, the OLT201 may allocate subcarriers and timeslots to the traffic of different service levels of each ONU according to the bandwidth allocated to each ONU in the target community as follows:

according to the residual CoS recorded in the report packet of the current period₁Traffic volume of service, CoS transmitted in current period for target ONU₁Traffic allocates subcarriers and slots, where the remaining CoS₁The service volume of the service is the CoS cached by the target ONU in the current period₁Total traffic of traffic — Pre-allocated CoS recorded in last cycle's gate packet₁CoS to be sent in a sub-period₁Traffic of a service, one cycle includes: CoS₁/CoS₂Sub-period, CoS₀Subcycle and Pre-allocated CoS₁A sub-period;

In particular, estimated CoS₁The traffic volume of the service may be: according to CoS generated in the interval of adjacent report packets in the first sixth preset number of periods₁The service volume of the service, calculating the above-mentioned each CoS₁Traffic volume obtained from an average of traffic volumes of the services.

In another preferred embodiment of the present invention, one cycle may include: CoS₁/CoS₂Sub-period, CoS₀Subcycle and Pre-allocated CoS₁And (4) sub-period.

Specifically, each ONU is specifically used in CoS₁/CoS₂In the sub-period, its corresponding CoS is sent to OLT201₁/CoS₂A service;

each one ofONU in CoS₀In the sub-period, its corresponding CoS is sent to OLT201₀Service, wherein each ONU transmits a CoS₀The service is as follows: CoS in the next cycle₀The service of (2);

pre-allocating CoS for each ONU₁In the sub-period, the corresponding service is sent to the OLT201, where the service sent by each ONU is: estimated CoS₁The estimated CoS is the minimum value between the service volume of the service and the service volume of the service which can be sent by the fifth preset number of subcarriers₁The traffic volume of the service is: according to CoS generated in the interval of adjacent report packets in the first sixth preset number of periods₁And the service volume of the service is calculated.

Since each ONU is in the CoS₀CoS sent to OLT201 in a sub-cycle₀The service is as follows: CoS in the next cycle₀In pre-allocating CoS₁The service sent to the OLT201 in the sub-period is: estimated CoS₁Traffic volume of traffic, so for the subsequent CoS₀Traffic and partial CoS₁In service, the OLT201 does not need to wait for a gate packet any more, thereby reducing system delay.

Optionally, the fifth preset number may be 2, and the service sent by each ONU may be: CoS generated in adjacent report packet interval in the first sixth preset number of periods₁The minimum between the average traffic of the traffic and the traffic of which 2 subcarriers can transmit the traffic.

There is room on each ONU side for caching different class of service traffic and, in addition, CoS is well known to those skilled in the art₀Highest priority of service, CoS₀The loss of service data often seriously affects the communication qualityTherefore, to prevent use for storing CoS₀The situation that the buffer space of the service is full causes CoS₀In another embodiment of the present invention, each ONU is further configured to detect a CoS for buffering₀If the space of the service is full, if the space is used for caching the CoS₀Detecting for caching CoS if the space of the service is full₂If the space of the service is full, if the space is used for caching the CoS₂If the space of the service is not full, the CoS is used₀Storing traffic to for caching CoS₂The space of the service.

In the above embodiment, the method is used for caching CoS₀Under the condition that the space of the service is full, each ONU leads the CoS₀Service caching to CoS caching₂The space of service, therefore, to prevent the data fetch error from the corresponding buffer space when each ONU transmits data, the CoS is generated₀Service caching to CoS caching₂In the case of a space of a service, the occurrence of the above-described situation can be expressed by a certain number of bits.

As can be seen from the above, the optical network system provided in this embodiment includes a plurality of communities, and each community may correspond to a different service range, so that compared with the optical network system in the prior art that only includes one community, the optical network system provided in this embodiment may provide communication services for users in a wider range.

The optical network system provided by the embodiment of the present invention is further described in detail by a specific example.

Fig. 3 is a schematic structural diagram of an optical network system according to an embodiment of the present invention.

The optical network system includes: OLT 301, ODN 302, cluster 1, cluster 2, cluster 3, and cluster 4.

The service ranges corresponding to the community 1 to the community 4 are respectively as follows: 10km, 40km, 70km and 100 km.

The ODN 302 comprises 4 optical splitters, optical splitter 1, optical splitter 2, optical splitter 3 and optical splitter 4.

Community 1 contains 4 sub-communities: a sub-population 1, a sub-population 2, a sub-population 3 and a sub-population 4;

community 2 contains 4 sub-communities: a sub-population 5, a sub-population 6, a sub-population 7 and a sub-population 8;

community 3 contains 4 sub-communities: a sub-population 9, a sub-population 10, a sub-population 11, a sub-population 12;

community 4 contains 4 sub-communities: sub-population 13, sub-population 14, sub-population 15, sub-population 16.

Sub-cluster 16 includes ONU1, ONU2, ONU3, and ARN, and ONU1, ONU2, and ONU3 are connected to the ARN in communication.

The specific structures of sub-population 1 to sub-population 15 may be identical to that of sub-population 16, and are not described herein again.

The OTL 301 is in communication connection with the community 1 through an optical splitter 1, in communication connection with the community 2 through an optical splitter 2, in communication connection with the community 3 through an optical splitter 3, and in communication connection with the community 4 through an optical splitter 4.

Specifically, the ARNs in the sub-population 1 to the sub-population 4 included in the population 1 are communicatively connected to the OLT 301 via the optical splitter 1, and the four sub-populations share the wavelength 2 realized by the optical splitter 1^qSub-carriers, where q is an integer greater than 0, e.g., 2^qMay be 64, 256, etc.;

the ARNs in subgroups 5 to 8 included in the community 2 are communicatively connected to the OLT 301 via the optical splitter 2, and the four subgroups share 2 at one wavelength implemented by the optical splitter 2^qA subcarrier;

the ARNs in subgroups 9 to 12 included in the community 3 are communicatively connected to the OLT 301 via the optical splitter 3, and the four subgroups share 2 of one wavelength implemented by the optical splitter 3^qA subcarrier;

the ARNs in subgroups 13 to 16 included in the community 4 are communicatively connected to the OLT 301 via the optical splitter 4, and the four subgroups share 2 at one wavelength implemented by the optical splitter 4^qAnd (4) sub-carriers.

OLT 301 may allocate bandwidth, subcarriers, and time slots to ONUs in each sub-cluster included in clusters 1 to 4.

The ONUs in each of the subgroups included in the community 1 to the community 4 may send traffic of different service levels to the OLT 301.

As can be seen from the above, in both the optical network system in the prior art and the novel optical network system provided in the embodiment of the present invention, the OLT needs to allocate a bandwidth to each ONU.

Referring to fig. 4, fig. 4 is a schematic flowchart of a bandwidth allocation method according to an embodiment of the present invention, where the method is applied to an optical network terminal OLT in an optical network system, where the optical network system includes: the optical network unit comprises an OLT and a first preset number of communities, wherein each community comprises at least one optical network unit ONU.

The first predetermined number is greater than or equal to 1.

That is to say, the bandwidth allocation method provided by the embodiment of the present invention can be applied to: all the OLTs in the optical network system including the OLT and the community, where a community in the optical network system includes at least one ONU, and when the optical network system includes a plurality of communities, the number of ONUs included in each community may be equal or may not be equal, which is not limited in this application.

The bandwidth allocation method comprises the following steps:

s401: and receiving the bandwidth demand information of the target community in the current period.

In this step, the target community may be a community included in the optical network system in the prior art, or may be one of a plurality of communities included in the optical network system provided in the embodiment of the present invention.

Specifically, the bandwidth requirement information may include: and each ONU in the target community sends information such as the traffic volume of the service under different service levels to the OLT.

CoS (Class of Service) is a method of managing network paths by a similar grouping method. For each class, it has its own level and priority. CoS is generally divided into three categories, denoted as: CoS₁、CoS₂And CoS₃。

S402: and selecting the modulation format of the ONU contained in the target community from multiple preset modulation formats according to the bandwidth demand information and a preset algorithm.

The preset modulation format may include: BPSK (Binary Phase Shift Keying), QPSK (Quadrature Phase Shift Keying), 16QAM (Quadrature amplitude Modulation), 32QAM, and the like.

In an optional implementation manner of the present invention, when the modulation format of the ONU included in the target community is selected from multiple preset modulation formats according to the bandwidth requirement information and a preset algorithm, cost factors corresponding to the ONUs included in the target community under each preset modulation format may be respectively calculated according to the bandwidth requirement information, and then the preset modulation format corresponding to the smallest cost factor is selected from the results as the modulation format of the ONUs included in the target community.

And the cost factor is used for representing the estimated cost value of the ONU contained in the target community when the ONU is modulated by adopting the current modulation format.

Specifically, when the cost factors corresponding to the ONUs included in the target community under each preset modulation format are respectively calculated according to the bandwidth requirement information and the preset algorithm, the cost factors corresponding to the ONUs included in the target community under each preset modulation format can be respectively calculated according to the bandwidth requirement information and the following expressions,

cost factor

Wherein i represents the cycle number of the current cycle, j represents the mark of the preset modulation format, l represents the distance between the OLT and the target community,a delay weight coefficient representing the ith period,represents the power weight coefficient of the ith period,

rtv_τ_i,lfor a first class of service CoS in the i-1 th cycle₀Time delay of (1) and CoS in the first i-1 cycles₀Rtv _ b, the ratio between the average time delays of_i,lCoS of all ONUs in bandwidth requirement of ith period of target community₀Sum of bandwidth requirements and CoS in the first i cycles₀Rtv _ p, the ratio between the average bandwidth requirements_i,lThe ratio of the required received power of the i-1 th period to the average received power of the first i-1 periods at the preset error rate,

τ_j,ldenotes the CoS for the modulation format denoted j at the distance l between OLT and target community₀Time delay of p_j,lIndicating that a modulation format identified as j is preset with a default error for the distance l between the OLT and the target communityThe required received power at the code rate,

f () is about τ_j,lG () as to p_j,lThe mapping function of (2).

The two mapping functions are mainly for tau_j,l、p_j,lAnd (6) carrying out normalization processing.

Alternatively to this, the first and second parts may,

It should be noted that, the present application is only described above as an example, and other normalization functions similar to the mapping function described above may also be used in practical applications.

The above modulation format selection algorithm comprehensively considers various factors of a physical layer and a Media Access Control (MAC) layer, specifically, the factors include: the method comprises the following steps of base band rate, transmission distance of the ONU, splitting ratio, allowable receiving error rate, modulation format, energy consumption, network load and time delay, wherein the first 3 factors are fixed for the determined ONU, and the allowable receiving error rate can be preset according to specific application conditions, so that for a determined optical network, the modulation format and the energy consumption need to be considered in the aspect of a physical layer, and the network load and the time delay need to be considered in the aspect of an MAC layer. The modulation format directly affects the physical layer parameter signaling rate, and further affects the transmission quality of the service, i.e., the average delay of the service and the uplink access bandwidth. In addition, there is a relationship between modulation format and energy consumption, and network load influences which modulation format is used, and thus these factors are mutually restricted and mutually influenced.

It should be noted that, for a transmission link with a certain length, the transmission loss of the whole link from the transmitting end to the receiving end is fixed, so the receiving power is a factor affecting the energy consumption, that is: the energy consumption is related to the received power of the receiving end, and therefore, the energy consumption can be expressed by using the received power.

As can be seen from the above analysis, the modulation format can relate network load, delay and received power, and thus relate parameters to be considered by the physical layer and the MAC layer.

S403: the available bandwidth is determined based on the selected modulation format and physical bandwidth.

It should be noted that the bandwidth in practical application may be expressed in terms of a bit rate or a baud rate, and in this embodiment, the bandwidth is expressed in terms of a bit rate.

S404: and allocating the bandwidth for each ONU in the target community according to the bandwidth requirement of the target community and the determined available bandwidth.

The specific algorithm for allocating bandwidth to each ONU in the target community belongs to a relatively mature technology, and can be easily obtained by those skilled in the art according to professional knowledge.

An optional specific algorithm for allocating bandwidth to each ONU in the target community is listed below, and the algorithm includes:

classification into CoS at class of service₁、CoS₂And CoS₃Under the three types of conditions, the bandwidth requested by any ONU in the bandwidth requirements of the target community in the current periodCan be expressed as:wherein i represents the identification of the ONU in the target community, and j represents the service level.

Before allocating bandwidth to each ONU in the target community, allocating guaranteed bandwidth to each ONUThe guaranteed bandwidth is a bandwidth allocated to the ONU according to the current available bandwidth under the condition that the ONU needs not to send the traffic.

It can be understood that, in general, some ONUs in the target community need to send less traffic, which is smaller than the othersWhile other ONUs need to send a larger amount of traffic, which is greaterBased on the two situations, when the amount of traffic that the ONU needs to transmit is small, the accumulated residual bandwidth will be generatedWherein,m represents in the target communityThe accumulated residual bandwidth can be allocated to the ONUs with larger traffic to be sent, so as to ensure the communication quality of the ONUs.

Based on the above description, the bandwidth allocated to each ONU in the target communityCan be expressed as:

wherein,the remaining bandwidth allocated for the ONU identified as i, specifically,

k representsK denotes the identity of the ONU in set K.

S405: and allocating subcarriers and time slots for the services of different service levels of each ONU according to the bandwidth allocated to each ONU in the target community.

Specifically, the sub-carriers and the time slots may be allocated to the services of different service levels of each ONU according to the bandwidth allocated to each ONU in the target community as follows:

according to the residual CoS recorded in the report packet of the current period₁Traffic volume of service, CoS transmitted in current period for target ONU₁Traffic allocation subcarriers and time slots, wherein the remaining CoS₁The service volume of the service is the CoS cached by the target ONU in the current period₁Total traffic of traffic — Pre-allocated CoS recorded in last cycle's gate packet₁CoS to be sent in a sub-period₁Traffic of a service, one cycle includes: CoS₁/CoS₂Sub-period, CoS₀Subcycle and Pre-allocated CoS₁Sub-weekA period;

Optional, estimated CoS₁The traffic volume of the service may be: according to CoS generated in the interval of every two adjacent report packets in the period of the first preset number of periods₁The service volume of the service, calculating the above-mentioned each CoS₁Traffic volume obtained from an average of traffic volumes of the services.

In the process that the OLT allocates bandwidth to each ONU in the target community, the OLT selects a modulation format for the ONUs included in the target community according to the bandwidth demand information of the target community in the current period, instead of using an agreed modulation format, and therefore the OLT needs to send the selected modulation format information to the corresponding ONUs. In a preferred embodiment of the present invention, the method for allocating bandwidth further includes, after selecting a modulation format of an ONU included in a target community from a plurality of preset modulation formats according to a preset algorithm and bandwidth requirement information;

and identifying the modulation formats of the ONUs contained in the target community by using a third preset number of bytes in the gate packet of the current period, so that the ONUs contained in the target community obtain the modulation formats by analyzing the received gate packet of the current period.

For example, the modulation format of the ONUs included in the target community is identified by 1 byte, so that the ONUs included in the target community obtain the modulation format by parsing the received gate packet of the current cycle.

In summary, in the process that the OLT allocates the bandwidth to each ONU in the target community, the communication between the OLT and the ONU in one period can be simply described as: and after all the steps are finished, writing the information of the modulation format, the allocated bandwidth, the allocated subcarriers, the allocated time slots and the like into a gate packet and sending the information to each ONU end of the target community, so that each ONU of the target community can communicate with the OLT according to the information contained in the received gate packet.

As can be seen from the above, in the scheme provided in this embodiment, the OLT selects a modulation format for the ONUs included in the target community according to the received bandwidth demand information of the target community in the current period, further determines an available bandwidth, and allocates a bandwidth to each ONU in the target community according to the determined available bandwidth. Compared with the prior art, in the scheme provided by this embodiment, when allocating bandwidth for each ONU in the target community, bandwidth requirement information of the target community is considered, and for different bandwidth requirements of the target community, the same preferred modulation format is selected for each ONU in the community, so as to obtain different available bandwidths, thereby satisfying the bandwidth requirements of the ONUs of each community under different conditions, and improving user experience.

Corresponding to the bandwidth allocation method, the embodiment of the invention also provides a bandwidth allocation device.

Fig. 5 is a schematic structural diagram of a bandwidth allocation apparatus according to an embodiment of the present invention, where the apparatus is applied to an optical network terminal OLT in an optical network system, where the optical network system includes: the optical network unit comprises an OLT and a first preset number of communities, wherein each community comprises at least one optical network unit ONU.

The bandwidth allocation apparatus includes: a bandwidth requirement information receiving module 501, a modulation format selecting module 502, an available bandwidth determining module 503, a bandwidth allocating module 504 and a subcarrier and time slot allocating module 505.

The bandwidth demand information receiving module 501 is configured to receive bandwidth demand information of a target community in a current period;

a modulation format selection module 502, configured to select, according to the bandwidth requirement information and according to a preset algorithm, a modulation format of an ONU included in the target community from multiple preset modulation formats;

an available bandwidth determining module 503, configured to determine an available bandwidth according to the selected modulation format and the physical bandwidth;

a bandwidth allocation module 504, configured to allocate bandwidth to each ONU in the target community according to the bandwidth requirement of the target community and the determined available bandwidth;

and a subcarrier and timeslot allocation module 505, configured to allocate subcarriers and timeslots to services of different service levels of each ONU according to the bandwidth allocated to each ONU in the target community.

In an optional embodiment of the present invention, the modulation format selection module 502 includes: a cost factor calculation sub-module and a modulation format selection sub-module (not shown in the figure).

The cost factor calculation sub-module is configured to calculate, according to the bandwidth demand information, cost factors corresponding to ONUs included in the target community under each preset modulation format, where the cost factors are used to represent estimated cost values of the ONUs included in the target community when the ONUs are modulated by using the current modulation format;

and the modulation format selection submodule is used for selecting the preset modulation format corresponding to the minimum cost factor as the modulation format of the ONU contained in the target community.

Preferably, the cost factor calculation sub-module is specifically configured to calculate, according to the bandwidth requirement information, cost factors corresponding to ONUs included in the target community under each preset modulation format according to the following expressions,

cost factor

Wherein i represents the cycle number of the current cycle, j represents the mark of the preset modulation format,l represents the distance between the OLT and the target community,a delay weight coefficient representing the ith period,represents the power weight coefficient of the ith period,

τ_j,lindicating the CoS for the modulation format denoted j at the distance l between the OLT and the target community₀Time delay of p_j,lIndicating the required received power at a preset bit error rate for the modulation format identified as j at a distance l between the OLT and the target community,

f () is about τ_j,lG () as to p_j,lThe mapping function of (2).

In particular, the method comprises the following steps of,

In a specific implementation manner of the present invention, the subcarrier and timeslot allocation module 505 includes: a first sub-carrier and time slot allocation submodule, a second sub-carrier and time slot allocation submodule, a third sub-carrier and time slot allocation submodule and a fourth sub-carrier and time slot allocation module (not shown in the figure).

The sub-carrier and time slot allocation module 505 is specifically configured to allocate sub-carriers and time slots to services of different service levels of each ONU according to the bandwidth allocated to each ONU in the target community through the following sub-modules;

a first sub-carrier and time slot allocation sub-module, configured to allocate a CoS in the next period according to the bandwidth requirement information₀Traffic of (1), CoS of target ONU₀The service allocates subcarriers and time slots;

a second sub-carrier and time slot allocation sub-module for allocating the estimated CoS recorded in the report packet according to the current period₁The traffic volume of the service is CoS transmitted by the target ONU in the idle time of the next period₁Traffic allocation subcarriers and timeslots, where estimated CoS₁The traffic volume of the service is: according to CoS generated in the interval of every two adjacent report packets in the period of the first preset number of periods₁The service volume of the service is calculated;

a third sub-carrier and time slot allocation sub-module for allocating the remaining CoS according to the remaining CoS recorded in the report packet of the current period₁Traffic volume of service, CoS transmitted in current period for target ONU₁Traffic allocation subcarriers and time slots, wherein the remaining CoS₁The service volume of the service is the CoS cached by the target ONU in the current period₁Total traffic of traffic — Pre-allocated CoS recorded in last cycle's gate packet₁CoS to be sent in a sub-period₁Traffic of a service, one cycle includes: CoS₁/CoS₂Sub-period, CoS₀Subcycle and Pre-allocated CoS₁A sub-period;

a fourth sub-carrier and time slot allocation sub-module for allocating the sub-module according to the third class of service class CoS in the current period₂Traffic of (1), CoS of target ONU₂Traffic allocates subcarriers and time slots.

Specifically, the second subcarrier and timeslot allocation sub-module is configured to allocate the estimated CoS according to the estimated CoS recorded in the report packet of the current period₁The traffic volume of the service is CoS transmitted by the target ONU in the idle time of the next period₁Traffic allocation subcarriers and timeslots, where estimated CoS₁The traffic volume of the service is: according to CoS generated in the interval of every two adjacent report packets in the period of the first preset number of periods₁The service volume of the service, calculating the above-mentioned each CoS₁Traffic volume obtained from an average of traffic volumes of the services.

Preferably, after the modulation format selection module 502 selects a modulation format for the ONUs included in the target community, the bandwidth allocation apparatus may further include: a modulation format identification module (not shown in the figure).

The modulation format identification module is configured to represent, in a gate packet of a current period, a modulation format of an ONU included in the target community by a third preset number of bytes, so that the ONU included in the target community obtains the modulation format by analyzing the received gate packet of the current period.

For the device and system embodiments, since they are substantially similar to the method embodiments, the description is simple, and for the relevant points, reference may be made to the partial description of the method embodiments.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

Those skilled in the art will appreciate that all or part of the steps in the above method embodiments may be implemented by a program to instruct relevant hardware to perform the steps, and the program may be stored in a computer-readable storage medium, which is referred to herein as a storage medium, such as: ROM/RAM, magnetic disk, optical disk, etc.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall fall within the protection scope of the present invention.

Claims

1. A bandwidth allocation method is applied to an optical network terminal (OLT) in an optical network system, wherein the optical network system comprises: the OLT and a first preset number of communities, each community comprising at least one optical network unit ONU, the method comprises the following steps:

according to the bandwidth allocated to each ONU in the target community, allocating subcarriers and timeslots to the services of different service levels of each ONU, including:

according to the residual CoS recorded in the report packet of the current period₁Traffic volume of service, CoS transmitted in current period for target ONU₁Traffic allocation subcarriers and time slots, wherein the remaining CoS₁The service volume of the service is the CoS cached by the target ONU in the current period₁Total traffic of traffic — Pre-allocated CoS recorded in last cycle's gate packet₁CoS to be sent in a sub-period₁Traffic of a service, one cycle includes: CoS₁/CoS₂Sub-period, CoS₀Subcycle and Pre-allocated CoS₁A sub-period;

2. The method according to claim 1, wherein selecting a modulation format of the ONUs included in the target population from a plurality of preset modulation formats according to a preset algorithm according to the bandwidth requirement information includes:

3. The method according to claim 2, wherein the calculating, according to the bandwidth requirement information and according to a preset algorithm, cost factors corresponding to ONUs included in the target community under each preset modulation format respectively includes:

cost factor

τ_j,lrepresents the CoS for the modulation format denoted j at the distance l between the OLT and the target community₀Time delay of p_j,lIndicating the required received power at a preset bit error rate for the modulation format identified as j at a distance l between the OLT and the target community,

f () is about τ_j,lG () as to p_j,lThe mapping function of (2).

4. The method of claim 3,

5. The method of claim 1, wherein the CoS generated in every two adjacent report packet intervals in the first second preset number of cycles₁The service traffic, the calculated traffic, includes:

6. A bandwidth allocation device is applied to an optical network terminal (OLT) in an optical network system, wherein the optical network system comprises: OLT and a first predetermined number of communities, each community including at least one optical network unit ONU, the apparatus comprising:

a subcarrier and time slot allocation module, configured to allocate subcarriers and time slots to services of different service levels of each ONU according to the bandwidth allocated to each ONU in the target community;

the subcarrier and timeslot allocation module comprises: a first sub-carrier and time slot distribution submodule, a second sub-carrier and time slot distribution submodule, a third sub-carrier and time slot distribution submodule and a fourth sub-carrier and time slot distribution module;

wherein, the first subcarrier and time slot allocation submodule is used for allocating CoS in the next period according to the bandwidth requirement information₀Traffic of (1), CoS of target ONU₀The service allocates subcarriers and time slots;

the second sub-carrier and time slot allocation sub-module is used for allocating the estimated CoS recorded in the report packet according to the current period₁The traffic volume of the service is CoS transmitted by the target ONU in the idle time of the next period₁Traffic allocation subcarriers and timeslots, where estimated CoS₁The traffic volume of the service is: every two adjacent repors in the period according to the first preset numberCoS generated in t-pack interval₁The service volume of the service is calculated;

the third sub-carrier and time slot allocation sub-module is used for allocating the remaining CoS according to the remaining CoS recorded in the report packet of the current period₁Traffic volume of service, CoS transmitted in current period for target ONU₁Traffic allocation subcarriers and time slots, wherein the remaining CoS₁The service volume of the service is the CoS cached by the target ONU in the current period₁Total traffic of traffic — Pre-allocated CoS recorded in last cycle's gate packet₁CoS to be sent in a sub-period₁Traffic of a service, one cycle includes: CoS₁/CoS₂Sub-period, CoS₀Subcycle and Pre-allocated CoS₁A sub-period;

the fourth sub-carrier and time slot allocation sub-module is used for allocating the sub-module according to the third class of service class CoS in the current period₂Traffic of (1), CoS of target ONU₂Traffic allocates subcarriers and time slots.

7. An optical network system, comprising:

each community comprises at least one sub-community;

each ONU sends services with different service levels to the OLT according to the bandwidth allocated to the OLT by the OLT;

wherein one cycle includes: CoS₁/CoS₂Sub-period, CoS₀Subcycle and Pre-allocated CoS₁A sub-period;

8. The optical network system of claim 7,

each ONU is further used for detecting the CoS for caching₀If the space of the service is full, if the space is used for caching the CoS₀Detecting for caching CoS if the space of the service is full₂If the space of the service is full, if the space is used for caching the CoS₂If the space of the service is not full, the CoS is used₀Service store to useIn cache CoS₂The space of the service.