CN101702674A - Transmission method of multicast data based on hybrid optical switching network - Google Patents

Abstract

The invention belongs to a transmission method of multicast data based on a hybrid optical switching network in the technology of network communication. The method comprises the steps of: setting the positions of each spectral node, dividing an internet area according to the spectral nodes, distributing a wavelength resource, building a multicast route, and transmitting multicast data. The method for setting up a network comprises: firstly, dividing the network into a plurality of small areas, setting only one spectral node in the each area, and setting the other nodes as common nodes to reduce the setting quantity, the cost and the occupancy quantity of the wavelength resource of the spectral nodes in a multicast network; in the field of network operating, organically combining an OCS all-optical network multicast technology with an OBS all-optical network multicast technology to enlarge the use ratio of bandwidth with the OBS technology in the area; and adopting a master-slave hybrid optical switching technology among the areas to reduce the packet loss rate. Therefore, the method can effectively reduce the setting quantity, the cost and the occupancy quantity of the wavelength resource of the spectral nodes in the multicast network, improves the use ratio of the bandwidth and the reliability of the network operation, and reduces the packet loss rate and the operation cost of the network, etc.

Description

A kind of transmission method of multicast data based on hybrid optical switching network

Technical field

The invention belongs to technical field of optical network communication, particularly a kind of transmission method that adopts hybrid optical switching network to carry out multi-case data.

Background technology

At present, basic optical-fiber network switching technology comprises: optical circuit exchanges, is OCS (Optical CircuitSwitching,), the light packet switching, be OPS (Optical Packet Switching,) and the light burst-switched, be OBS (Optical Burst Switching, OBS), though they have all realized full light exchange, respectively has certain features; But also all there is weak point separately, particularly in data conveying capacity frequent variations or be and carry out data when transmitting in the network environment of high sudden exchange, all have an obstacle that is difficult to overcome.Wherein:

The OCS switching technology connects by set up " circuit " that pass whole full optical core network network between edge router---and light path is carried out end-to-end transparent transmission to data.Yet this connection-oriented exchanged form is for the low shortcoming of support efficient utilance not high and light path under the less situation of traffic carrying capacity of the IP operation with high burst characteristic.In order to maximize the resource utilization of optical core network network, optimal mode is to provide the packet switching function at photosphere, i.e. the OPS switching technology.But, be difficult to practicability in a short time because there are some obstacles that are difficult to overcome in realization in the light packet switching.OBS is a kind of half-way house between OCS and the OPS, and it adopts the transmission data cell bigger than OPS granularity---converge the burst packets that forms by a plurality of light groupings and transmit.A corresponding control grouping---the burst head (BHP that produces of each burst packets, Bust Header Packet), BHP enters the control channel of core switching network prior to burst packets, is corresponding burst packets reservation interchange channel at each switching node place of approach, makes burst packets to exchange and transmit in full light mode.Owing to adopt resource reservation mechanism, so there is not the existing technology barrier that is difficult to overcome of OPS exchange in the OBS exchange; Simultaneously, OBS can carry out statistic multiplexing to network medium wavelength resource, effectively improves bandwidth availability ratio.But present OBS technology is not resolved the reservation collision problem, thereby has the higher defective of data-bag lost rate.

For in conjunction with the advantage of OCS and OBS and avoid or reduce its defective as far as possible, researchers propose OCS and OBS switching technology are combined, form the mixed light switching technology.At present, OCS/OBS hybrid switching optical network (hereinafter to be referred as mixed optical network) can be divided into three types: master-slave type mixed optical network, parallel type mixed optical network and integrated mixed optical network.The master-slave type mixed optical network two-layerly constitutes by client layer and service layer are upper and lower, and service layer adopts the OCS switching technology, and uses the part wavelength static or dynamically set up light path, and all light paths constitute virtual topology networks and are used for the client layer exchange; Client layer adopts the OBS switching technology, carries out the OBS exchange for business on the virtual topology network that service layer constitutes; This mode is still OBS exchange from essence, but realizes simply, and is easy to that to carry out all-optical network interconnected with the OBS network.In the parallel type mixed optical network, OCS light switching technology and the parallel existence of OBS switching technology and basic optical-fiber network of each self-forming are for business provides two kinds of exchanged forms; When business arrived, fringe node provided different switching technologies according to the difference of business demand, business is sent into different basic optical-fiber networks exchange, and in professional transport process, intermediate node can not change professional exchanged form.The shortcoming of parallel type mixed optical network is to adjust the exchanged form of its former setting according to network condition, and the exchange decision-making is dumb, and the while, how Internet resources being made rational planning for was an insoluble problem owing to IP operation is sudden.In integrated mixed optical network, each node all has OCS and OBS ability, can both though this mode is more flexible to the burst service support, realize complicated according to the professional exchanged form of network the present situation decision; In addition, business need be carried out the processing of electric territory when changing exchanged form.In addition, above-mentioned mixed light switching technology all is how to carry unicast service effectively at network, carries out multicast service and can not use it for.

Particularly along with the continuous development of network technology and the continuous variation of user's request, a large amount of multicast services continue to bring out.The all-optical network multicasting method mainly contains two kinds at present: all-optical network multicast in the OCS network and the all-optical network multicast in the OBS network.These two kinds of all-optical network multicasts all are to realize to the tree topology route (being called multicast tree) of all destination nodes by setting up source node.When wherein in the OCS network, making up the multicast tree network,, source node all is connected by light path with communication between any destination node by duplicating light signal (beam split) at the branch node place of multicast tree network.But one light path can the loaded service total amount usually can be up to tens of Gbps, and the bandwidth demand of existing multicast service has only tens to hundreds of Mbps usually, so the full light multicast bandwidth availability ratio in the OCS network is lower, improve bandwidth availability ratio though can utilize business to dredge, but multicast service to dredge the processing method complexity higher, realize difficulty.And in the OBS network,, as previously mentioned, exist the higher defective of data-bag lost rate to can not be ignored (fatal) in the OBS network though can improve bandwidth availability ratio by wavelength statistic multiplexing characteristic.

Be to realize in the OCS network or in the OBS network that the all-optical network multicast all needs node to have the beam split ability, be used for duplicating light signal at the branch node place of multicast tree, but the beam split meeting causes decay exponentially to light signal, power for inhibit signal, network node must dispose the image intensifer of certain gain, yet the cost that image intensifer is set is higher, so the cost of dividing optical node to be provided with in the network is higher relatively.In order to reduce the cost of building of network, the method that can adopt sparse configuration to divide optical node promptly only dispose the branch optical node of some in network, and other node all is configured to not have the node of beam split ability.But, in the multicast tree network of a multicast service, if have a plurality of destination nodes in a certain branch of branch optical node, and there is not other minute optical node in this branch, then will use more wavelength resource just can carry out multicast transmission, then will cause the destination node in this branch can not finish professional reception for the OBS network otherwise cause to carry out in this branch in the OCS network unicast service with occurring vying each other.Therefore, if beam split node configuration unreasonable (as: having great deal of nodes in the network is not the adjacent node of branch optical node) then can consume more wavelength resource and could cover all destination nodes increases the cost of multicast route.Thereby, in the above-mentioned all-optical network multicasting method: adopt the single multicast of OCS all-optical network, its bandwidth availability ratio low and adopt single OBS all-optical network multicast to have the higher defective of loss rate; Even under the sparse situation that the branch optical node is set, if divide optical node distribute (settings) unreasonable, then be employing OCS network, or the full light multicast of OBS network also all need take more wavelength resource.

Summary of the invention

The objective of the invention is defective at the background technology existence, a kind of transmission method of multicast data of research and design based on hybrid optical switching network, combine, adopt the multi-case data of hybrid optical switching network to transmit multicast of OCS all-optical network and the multicast of OBS all-optical network, and according to node distribution situation in the multicast tree network, guaranteeing to cover under the prerequisite of all destination nodes, adopt the method for optimizing of science that the branch optical node is set as few as possible; To reach the cost that effective reduction multicast network node is provided with and the occupancy of wavelength resource, improve the reliability of the bandwidth utilization and the network operation, reduce the purposes such as cost of the packet loss and the network operation.

Solution of the present invention is when network struction, and a macroreticular is divided into several close zonules of size, and according to the preferred setting principle of low amount of minute optical node, in each zone, only establish a branch optical node, all the other nodes all are made as ordinary node; Network operation aspect, then OCS and OBS all-optical network multicasting technology are organically combined, OBS multicast route is carried out the all-optical network multicast in intra-zone employing OBS switching technology, by the territory, between the zone then on the basis of full optical interconnection, adopt master-slave type mixed light switching technology, finish the all-optical network multicast by the OCS light path; The present invention promptly realizes its goal of the invention with this.Therefore, the inventive method comprises:

A., each minute optical node and divide the network area is set: determine the position of each minute optical node in network, and by the principle division of cells territory of only establishing a branch optical node in each zone, its step is as follows:

Step 1.0. determines the position of each minute optical node: at first the all-network node is considered as ordinary node, and successively with the adjacent node number of each node and the ratio of the minimum hop count summation of all the other nodes without minute optical node to this node, distance weighting value as this node, again according to the size of each node weights value, will be wherein the pairing node of weight limit value be made as the branch optical node, and then all the other each ordinary nodes except that this minute optical node are drawn the corresponding distance weighting value of each node successively by identical method, wherein the pairing node of maximum is made as the branch optical node; In the ordinary node of remainder, continue screening, the branch optical node be set according to this mode, when set each minute, the ordinary node that is adjacent of the optical node node number (simultaneously) that covered in the network whole nodes or remainder was less than that ordinary node is counted in branch optical node number and the Minimum Area only;

The mathematic(al) representation of each nodal distance weighted value is: $w_n=\frac{d_n}{\underset{i\≠n}{\underset{i\∈V}{\mathrm{\Σ}}}{h}_{\mathrm{ni}}}$

Wherein, w _nBe the distance weighting of node n, d _nBe ordinary node number in the adjacent node of node n, h _NiBe the minimum hop count of each ordinary node i without beam split node-to-node n;

Step 2.0. division of cells territory: by the principle of only establishing a branch optical node in each zone, with this minute optical node divide a zone into together with the ordinary node that is adjacent, after the regional assignment if the zone that not with the ordinary node of any beam split node adjacency, then puts the branch optical node affiliated area nearest with it or relative less (the node number is less) under arranged;

B. distribute wavelength resource: the zone divide fixed after, the wavelength resource that at first distributes the limited quantity that is no less than 2 from every physical link of whole network is as OBS control channel transmission BHP (burst head) and OBS data channel transmission burst packets; Then according to the multicast service amount of each Area Node, utilize that the unappropriated wavelength resource of all links is to set up interregional light path between per two branch optical nodes in the network; At last with the data channel of remaining wavelength resource as transmission OBS burst packets;

C. set up the multicast route:

Step 1.0. makes up route in the source region territory: make up multicast route in the territory of region, source according to the source and destination node of multicast service, make it cover all destination nodes of current region and branch optical node, change step 2.0 then;

Step 2.0. judges whether to carry out multicast between the territory: if the multicast service destination node comprises other Area Node, need carry out multicast between the territory, then change step 2.1;

Step 2.1. makes up inter-domain multicast routing: inter-domain multicast routing is the source with the branch optical node of source region, the branch optical node in all purpose zones is a destination node, and when arbitrary light path is overflowed in the multicast path between the territory, adopt itself and light path to replace the burst packets that this optic path is overflowed with the spillover route in path physically, change step 3.0;

Step 3.0. makes up route in the territory, purpose zone: to divide optical node in the territory is the source, makes it cover all destination nodes in the current region;

D. multi-case data transmits: when local multicast data stream enters network node, its processing procedure adopts following steps:

Step 1.0. is assembled into burst packets with multicast service, changes step 2.0;

Step 2.0. sets up BHP (burst head) according to burst packets, changes step 3.0;

Step 3.0. sends BHP reserve route resource: press the information reservation wavelength or the light path resource of BHP record, the reservation back is changeed step 4.0 and is sent burst packets; The reserve route resource comprises:

OBS data channel: BHP preengages the multicast route in the territory of step 3.1. reservation source region from source point along the OBS data channel in the region; If in the time of also need carrying out between the territory multicast or only need between the territory multicast, change step 3.2;

Data channel between step 3.2. reservation territory: at first,, then BHP directly is forwarded to the branch optical node in purpose zone if reservation light path resource is successful according to light path between the information reservation territory of BHP record; Otherwise preengage spillover route and transmit the branch optical node of BHP, change step 3.3 then to the purpose zone;

OBS data channel in the step 3.3. reservation purpose zone: when BHP arrives the branch optical node in purpose zone, the multicast route of reservation BHP;

Step 4.0. sends burst packets: when shift time then, source node sends the OBS burst packets, burst packets transmits through the data channel of reservation.

The present invention is because when network struction, a macroreticular is divided into the close zonule of several sizes, and according to the preferred setting principle of low amount of minute optical node, in each zone, only establish a branch optical node, all the other nodes all are made as ordinary node, divide the amount of setting of optical node and cost are set and the occupancy of wavelength resource to reduce multicast network; Network operation aspect then organically combines OCS and OBS all-optical network multicasting technology, adopt the OBS switching technology at intra-zone, by the territory in OBS multicast route resource carry out the all-optical network multicast, increased bandwidth availability ratio; And between the zone on the basis of full optical interconnection, adopt master-slave type mixed light switching technology, finish the all-optical network multicast, reduce losing of packet by the OCS light path.Thereby, the present invention has and can effectively reduce multicast network and divide the amount of setting of optical node and cost is set and the occupancy of wavelength resource, improve the reliability of the bandwidth utilization and the network operation, reduced the packet loss in the transmission course and the characteristics such as cost of the network operation.

Description of drawings

Network (NSFNET-14) the physical topology network diagram of Fig. 1 for constituting by 14 nodes in the specific embodiment of the invention;

The configuration that the node region of network was divided and divided optical node during Fig. 2 implemented for the present invention is concrete.

Fig. 3 is a multi-case data transmission schematic diagram in the specific embodiment of the invention

Embodiment

Accompanying drawing 1 is network (NSFNET-14) the physical topology network diagram that is made of 14 nodes, and the link in the network is two-way link, on every optical fiber four wavelength (λ is arranged on the network of present embodiment ₀～λ ₃).

A., each minute optical node and divide the network area is set:

Step 1.0. determines the position of each minute optical node: the distance weighting with each node serves as according to the branch optical node being set, establishing w _nBe the distance weighting of node n, d _nBe ordinary node number in the adjacent node of node n, h _NiBe the minimum hop count of ordinary node i without beam split node-to-node n, the distance weighting w of each node n _nThen get by following formula:

$w_n=\frac{d_n}{\underset{i\≠n}{\underset{i\∈V}{\mathrm{\Σ}}}{h}_{\mathrm{ni}}}$

For node 0: node 0 in abutting connection with ordinary node 3, d are then arranged ₀Be 3; Simultaneously node 1 minimum hop count of each node-to-node 0 to the node 13 respectively is followed successively by: 1,1,1,2,2,3,2,3,3,3,3,3,2;

Then: $\underset{i\≠0}{\underset{i\∈V}{\mathrm{\Σ}}}{h}_{0i}=1+1+1+2+2+3+2+3+3+3+3+3+2=29;$

Node 0 distance weighting be: ${\mathrm{<figure-callout\; id="0"\; label="w"\; filenames="H2009102161581E0000021.png"\; state="\{\{state\}\}">w</figure-callout>}}_0=\frac{{\mathrm{<figure-callout\; id="0"\; label="d"\; filenames="H2009102161581E0000021.png"\; state="\{\{state\}\}">d</figure-callout>}}_0}{\underset{i\&NotEqual;0}{\underset{i\&Element;V}{\mathrm{\&Sigma;}}}{h}_{0i}}=\frac{3}{29}=0.103$

Equally, obtain the distance weighting value of all the other nodes and by ordering from big to small be successively: 0.167,0.16,0.111,0.111 with the distance weighting of all nodes, 0.107,0.107,0.107,0.107,0.103,0.103,0.103,0.103,0.069,0.067, correspond respectively to node 5,7,3,4,1,2,9,10,0,11,12,13,8,6; Wherein the distance weighting maximum of node 5 is set to first minute optical node; In like manner, calculate the distance weighting of removing remaining 13 ordinary nodes in branch optical node 5 backs, wherein the distance weighting maximum of node 7 then is set to node 7 second branch optical node; Then, from remove branch optical node 5 and 7 remaining 12 nodes, filter out node 13 once more and it is set to the 3rd branch optical node; Owing to divide optical node 5,7,13 and adjacent node thereof to cover all nodes of removing node 0 in the network, setting completed to divide optical node;

Step 2.0. division of cells territory: by the principle of only establishing a branch optical node in each zone, at first will with minute optical node 5,7,13 respectively adjacent node put three zones of I, II, III of corresponding minute optical node representative under; Because node 0 is identical with the distance of dividing optical node 5,7,13, then it is put under the II zone under the minimum branch optical node of present node 7 in the present embodiment; Then three zones are respectively: area I comprises: 1,4,5,8, and 9 five nodes; Area I I comprises: 0,2,6,7, and 10 5 nodes; Area I II comprises: 3,11,12,13 four nodes;

B. distribute wavelength resource: at first from every physical link of the whole network, reserve two wavelength resources, one of them wavelength (λ ₀) as control channel transmission BHP, another wavelength wavelength (λ ₁) as OBS data channel transmission burst packets; Then according to the multicast service amount of each Area Node, utilize that the vacant wavelength resource of all links is to set up light path between the territory between per two branch optical nodes in the network.In this implementation column, light path is respectively between the territory of structure: 5-8-7 (λ ₃), 7-8-5 (λ ₃), 7-10-11-13 (λ ₃), 13-11-10-7 (λ ₃), 5-9-12-13 (λ ₃), 13-12-9-5 (λ ₃), at last with remaining wavelength resource in the network all as the data channel of transmission OBS burst packets.

C. set up the multicast route: present embodiment is 2 so that a source node to be arranged in the network, and destination node is that 0,1,4,10,12 multicast service is an example, and its multicast route is:

Step 1.0. makes up route in the source region territory: the source and destination node according to multicast service makes up multicast route in the territory, region, source, the multicast route then is by being the source with source node 2 in this territory, cover all destination nodes 0,10 of current region and divide optical node 7 and link (2,0), (2,7), (7,10) the OBS data channel on is formed, and changes step 2.0;

Step 2.0. judges whether to carry out multicast between the territory: because this multicast service destination node comprises other Area Nodes (node 1,4 of area I and the node 12 of area I II), change step 2.1;

Step 2.1. makes up inter-domain multicast routing: inter-domain multicast routing then is to be the source by the branch optical node 7 with source region II, and the branch optical node 5 of purpose area I, III and 13 is that light path 7-13 and 7-5 form between destination node and territory; With the spillover route of light path 7-13 and 7-5 between time domain is respectively OBS data channel on OBS data channel on link (7,10), (10,11), (11,13) and link (7,8), (8,5); Change step 3.0;

Step 3.0. makes up route in the territory, purpose zone: the multicast route is by being the source with minute optical node 5 in area I, in the territory, covers all destination nodes 1 and 4 of current region, and the OBS data channel composition on the link (5,1), (5,4); The multicast route then only is made up of the OBS data channel on minute optical node 13, destination node 12 and the link (13,12) in area I II, in this territory;

D. multi-case data transmits: when this multicast data stream enters network node, its transport process is as follows:

Step 1.0. sends into multicast service and converges buffer memory and be assembled into burst packets, changes step 2.0;

Step 2.0. sets up BHP according to burst packets; Change step 3.0;

Step 3.0. sends BHP reserve route resource: press the information reservation wavelength or the light path resource of BHP record, the step of reserve route resource comprises step 3.1～3.3, and the reservation back is changeed step 4.0 and sent burst packets;

OBS data channel in the step 3.1. reservation source region: BHP preengages the OBS data channel on link (2,0), (2,7), (7,10) from the source point 2s.Because this multicast service need carry out multicast between the territory, change step 3.2;

Data channel between step 3.2. reservation territory: receive BHP when minute optical node 7, duplicate two BHP and be respectively applied for reservation light path 7-13 and light path 7-5; If light path is preengage successfully, then BHP directly is forwarded to the branch optical node in purpose zone; Otherwise preengage spillover route and transmit the branch optical node of BHP to the purpose zone; Change step 3.3 then;

OBS data channel in the step 3.3. reservation purpose zone: when BHP arrival destination node is divided optical node 5, duplicate and send the OBS data channel on BHP reservation link (5,1), (5,4).When BHP arrival destination node is divided optical node 13, send the OBS data channel on the BHP reservation link (13,12).

Step 4.0. sends burst packets: when shift time then, source node sends the burst packets of being sent into by step 3.0, burst packets (comprises link among the area I I (2,0), (2,7), (7 through the data channel of reservation, 10) the OBS data channel on, light path 7-13,7-5 and corresponding spillover route thereof between the territory, link in the area I (5,1), (5,4) the OBS data channel among OBS data channel on and the area I II on the link (13,12)) transmit.Accompanying drawing 3 is this multi-case data transmission schematic diagram.

In the present embodiment accompanying drawing:

Expression divides optical node,

The expression ordinary node;

The OBS data channel on this link is not preengage in expression,

OBS data channel on this link of expression reservation is as multicast route in the territory ... OBS data channel on this link of expression reservation is as spillover route,

Light path between the territory that expression has been preengage, Light path between the territory that expression is not preengage;

The burst packets of multicast route transmission in the territory is passed through in expression,

The burst packets of optic path between the territory is passed through in expression,

Expression is by the burst packets of spillover route transmission.

Claims (1)

1. transmission method of multicast data based on hybrid optical switching network comprises:

A., each minute optical node and divide the network area is set: determine the position of each minute optical node in network, and by the principle division of cells territory of only establishing a branch optical node in each zone, its step is as follows:

Step 1.0. determines the position of each minute optical node: at first the all-network node is considered as ordinary node, and successively with the adjacent node number of each node and the ratio of the minimum hop count summation of all the other nodes without minute optical node to this node, distance weighting value as this node, again according to the size of each node weights value, will be wherein the pairing node of weight limit value be made as the branch optical node, and then all the other each ordinary nodes except that this minute optical node are drawn the corresponding distance weighting value of each node successively by identical method, wherein the pairing node of maximum is made as the branch optical node; In the ordinary node of remainder, continue screening, the branch optical node be set according to this mode, when set each minute, the ordinary node that is adjacent of the optical node node number that covered in the network whole nodes or remainder was less than that ordinary node is counted in branch optical node number and the Minimum Area only;

The mathematic(al) representation of each nodal distance weighted value is: $w_n=\frac{d_n}{\underset{i\&NotEqual;n}{\underset{i\&Element;V}{\mathrm{\&Sigma;}}}{h}_{\mathrm{ni}}}$

Wherein, w _nBe the distance weighting of node n, d _nBe ordinary node number in the adjacent node of node n, h _NiBe the minimum hop count of each ordinary node i without beam split node-to-node n;

Step 2.0. division of cells territory: by the principle of only establishing a branch optical node in each zone, with this minute optical node divide a zone into together with the ordinary node that is adjacent, after the regional assignment if having not with the ordinary node of any beam split node adjacency, then put branch optical node affiliated area nearest or relative less zone under with it;

B. distribute wavelength resource: after the zone branch was fixed, the wavelength resource that at first distributes the limited quantity that is no less than 2 from every physical link of whole network was as OBS control channel transmission BHP and OBS data channel transmission burst packets; Then according to the multicast service amount of each Area Node, utilize that the unappropriated wavelength resource of all links is to set up interregional light path between per two branch optical nodes in the network; At last with the data channel of remaining wavelength resource as transmission OBS burst packets;

C. set up the multicast route:

Step 1.0. makes up route in the source region territory: make up multicast route in the territory of region, source according to the source and destination node of multicast service, make it cover all destination nodes of current region and branch optical node, change step 2.0 then;

Step 2.0. judges whether to carry out multicast between the territory: if the multicast service destination node comprises other Area Node, need carry out multicast between the territory, then change step 2.1;

Step 2.1. makes up inter-domain multicast routing: inter-domain multicast routing is the source with the branch optical node of source region, the branch optical node in all purpose zones is a destination node, and when arbitrary light path is overflowed in the multicast path between the territory, adopt itself and light path to replace the burst packets that this optic path is overflowed with the spillover route in path physically, change step 3.0;

Step 3.0. makes up route in the territory, purpose zone: to divide optical node in the territory is the source, makes it cover all destination nodes in the current region;

D. multi-case data transmits: when local multicast data stream enters network node, its processing procedure adopts following steps:

Step 1.0. is assembled into burst packets with multicast service, changes step 2.0;

Step 2.0. sets up BHP according to burst packets, changes step 3.0;

Step 3.0. sends BHP reserve route resource: press the information reservation wavelength or the light path resource of BHP record, the reservation back is changeed step 4.0 and is sent burst packets; The reserve route resource comprises:

OBS data channel: BHP preengages the multicast route in the territory of step 3.1 reservation source region from source point along the OBS data channel in the region; If in the time of also need carrying out between the territory multicast or only need between the territory multicast, change step 3.2;

Data channel between step 3.2 reservation territory: at first,, then BHP directly is forwarded to the branch optical node in purpose zone if reservation light path resource is successful according to light path between the information reservation territory of BHP record; Otherwise preengage spillover route and transmit the branch optical node of BHP, change step 3.3 then to the purpose zone;

OBS data channel in the step 3.3 reservation purpose zone: when BHP arrives the branch optical node in purpose zone, the multicast route of reservation BHP;

Step 4.0. sends burst packets: when shift time then, source node sends the OBS burst packets, burst packets transmits through the data channel of reservation.

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