A kind of SDH network planning design method of multi-modularized optical fiber
Technical field
The invention belongs to the computer network communication technology field, be specifically related to optical fiber SDH network planning design, relate to the resource management and the maintenance of optical fiber SDH network simultaneously.
Background technology
In current society, along with the development of communication, the information that people require to transmit is not only literal, also has data, speech, image and video etc., and network is had higher requirement.Equally, people also more highly rely on various networks.In various networks, SDH (Synchronous Digital Hierarchy, SDH (Synchronous Digital Hierarchy)) network has obtained huge development in wide area network field and private network field.SDH can realize that network is effectively managed, real time business is monitored, dynamic network is safeguarded, the multinomial functions such as intercommunication of different vendor's equipment room, can improve network resource utilization greatly, reduce administrative and maintenance expense, therefore be the development of world today's message area aspect transmission technology and the focus of application, be subjected to people's extensive attention.
Nowadays, how economical, plan that SDH mesh (SDH is netted) network becomes a research focus of the world today effectively.Wherein, SDH Mesh network capacity design problem becomes an emphasis of the network planning, thereby the protection route that promptly how to design professional work route and correspondence all is protected all business, and makes that finally the total resources of network are minimum.
The planning and designing problem of SDH mesh network mainly contains two research directions: link capacity non-modularization or modularization.The non-modularization method is meant does not consider that in the Capacity design process of link physical fiber is equipped with, and the capacity of Theoretical Calculation is the capacity of link actual disposition; Modular method is meant considers that in the Capacity design process of link physical fiber is equipped with, and the capacity of Theoretical Calculation can be instantiated as actual physical fiber type capacity.Modular method is divided into single mode blocking and multimode blocking again.Wherein, if network is only supported a kind of physical fiber type, then be called the single mode blocking; If network can be supported multiple physical fiber type, then be called the multimode blocking.Usually because the multimode blocking has more capacity levels, thereby can be under the situation of less increase link capacity the capacity of the concrete link of more accurate design.
At present, industry has proposed some feasible modularization Capacity design methods.Document 1-" W.D.Grover; T.D.Bilodeau; B.D.Venables; " Near optimal spare capacity planning in a mesh restorable network; " Global TelecommunicationsConference, 1991.GLOBECOM ' 91, Page (s): 2007-2012 vol.3. " capacity that a kind of heuristic comes planned network proposed.This heuristic adopts the protection capacity of alternative manner computing service under the prerequisite of given working capacity, reduce cost by subduing optical fiber more at last.This method time efficiency is low, and the result neither be optimum, and only supports the optical fiber of single mode blocking (OC-N).
Document 2-" J.Doucette; W.D.Grover; " Influence of modularity and economy-of-scale effects on design ofmesh-restorable DWDM networks; " Selected Areas in Communications; IEEE Journal on Volume 18; Issue10, Oct.2000Page (s): 1912-1923. " adopt the integer programming method of operating path and protection path combined optimization to solve the capacity allocation problem.This method is set up the Mathematical Modeling of multimode blocking problem earlier, comes Mathematical Modeling is found the solution by calling the CPLEX software that runs on the AMPL model system then, draws optimum solution at last.The input of Mathematical Modeling comprises by the alternative route set of each business of the program generation of C language compilation, also comprises following supposition input parameter:
D: the sum that node is right, these nodes between service request must be arranged;
S: the link sum in the network;
M: always total how many kinds of optic module;
d
r: r node between service bandwidth;
: at the optional work route the inside of the right business of r node, the longest path jumping figure;
Q
r: the sum of the optional work route of the business that r node is right;
: if in the optional route set the inside of the right business of r node, q bar route is through link j, and then this parameter value is 1, otherwise is 0;
: the cost of last m the module of link j;
Z
m: the capacity of m module;
L
i: the recovery rate of link i appointment, acquiescence 1;
P
i: if link i lost efficacy, for recovering the number that link precomputes the right alternative route of the source order node of the link i that comes
: during through link j, this value is 1 for the p bar route of recovering the alternative route set the inside that i bar link calculates;
The variable of using in this model has:
g
R, q: the working capacity that the optional route of the q bar of the business that r node is right needs
w
j: the working capacity on the link j
s
j: link j goes up the protection capacity
: the protection capacity that the p bar route of process link i needs
The Model Optimization target is to make the optical fiber cost sum minimum that disposes in the network, is formulated as follows:
Its constraints comprises following five:
(1)
Working capacity above promptly guaranteeing when link i lost efficacy all is protected;
(2)
Link j has enough protection capacity when promptly guaranteeing link i inefficacy;
(3)
The work road of promptly guaranteeing the business that r node is right all is routed;
(4)
The computing formula of the working capacity on the link j;
(5)
, working capacity on the link and protection capacity sum are less than all optic module capacity sums.
This method at first calculates the route set that all satisfy constraint for each business, selects operating path and protection path simultaneously for business then in this route set, carries out capacity configuration at last and obtains separating of an optimum.This method is supported multimode (OC-N), but it is slow to find the solution speed, is not suitable for macroreticular.
Summary of the invention
The invention provides the SDH mesh network planning design method of a kind of known network topology (node location and internodal connection situation in the given network) and business demand.Considering that the final result resource is wanted modularization and given modular fiber type is under the situation of STM model, by calculating the resource optimize route assignment and LSP apace, finally makes the total cost minimum of network.The present invention adopts multimode blocking mode, and mainly the technical problem of Xie Jueing comprises following two:
When (1) single business is calculated, how to adopt the method for multimode blocking to design route and carry out capacity allocation, thereby make that the total cost of network is approaching minimum for professional;
(2) after all professional calculating finish, if disposed more than one type optical fiber on the link, how to carry out the combined optimization between the multimode, thereby further optimize the link capacity configuration of network, make that the total cost of network is littler.
Among the present invention, optionally the type of physical fiber is STM-N (N=1,4,16,64), promptly adopts multimode blocking mode.Because the multimode blocking has more capacity levels, usually can more accurate modularization link capacity, thus reduce because the capacity that modularization is brought increases.As the capacity that disposes on the link is 18M, when the optional fiber type of single mode blocking is STM-16 (capacity is 16M), needs the optical fiber of 2 STM-16 of configuration, causes link capacity to increase 14M; And the optional fiber type of multimode blocking is STM-N (N=1,4,16,64), then only needs the optical fiber of a STM-4 of configuration and a STM-16, and link capacity only need increase 2M, and is more excellent than the result of single mode blocking.
Under the STM-N model, different block size has different costs.When being carried out modular arrangements, capacity can have the combination of various modules.For example capacity value will is 10M, can turn to 3 STM-4 or 1 STM-16 to this capacity module.The cost of these two kinds of combinations is different, how to select the problem of optimum module combinations to be called the combined optimization problem of multimode blocking in the invention, chooses the compound mode of cost minimum as far as possible.
Technical solution of the present invention is as follows:
A kind of SDH network planning design method of multi-modularized optical fiber, node location and internodal connection situation and business demand in known network, and given modular fiber type is under the situation of STM model, by planning and designing, make and specifically may further comprise the steps network fiber cost minimum:
Step 1: professional ordering.All business in the network are sorted, and the rule of ordering is based on the bandwidth value of business, and the business that bandwidth value is big more has high more priority; For those bandwidth values business of the same size, then by the source of business demand, the jumping figure value ordering of the minimum hop count route between the order node, the business that jumping figure is more little has high more priority.
Step 2:, be followed successively by each professional searching route and carry out the fiber resource configuration according to business ordering order from high to low.Specifically may further comprise the steps:
Step 2-1: choose a highest business of collection of services medium priority, establishing the current business bandwidth is Bw;
Step 2-2: the link weight LinkWeight of all links in the computing network:
LinkWeight=NewAddCost×β+Bw×γ (1)
Wherein, NewAddCost is a link dilatation cost; Bw is the bandwidth of a service request.β is an adjustable parameter, usually between 0.1 to 10.Choosing according to the influence degree of dilatation cost of β value decided, and for example, if wish that the dilatation cost is big, then gets β=10; Otherwise, wish that the dilatation cost is little, then get β=0.1.γ is an adjustability coefficients, the unit cost of the optical fiber that coefficient gamma=cost of the present invention is the most cheap.
When calculating link weight LinkWeight, at first need to calculate the dilatation cost NewAddCost of link, its concrete computational methods are: if link does not need dilatation, then NewAddCost=0; If link need increase optical fiber newly, and newly-increased optical fiber can not produce with the optical fiber that disposed on the link and merges or replacement operation, then NewAddCost=Cost
n(Cost
nCost for newly-increased optical fiber); If can producing with the optical fiber that disposed on the link, the newly-increased optical fiber of link merges or replacement operation, then NewAddCost=Cost
nMerged on-the link or the cost sum of the optical fiber of replacing that has disposed; If calculate NewAddCost<0, promptly after the dilatation because optical fiber merges or replace the optical fiber cost that causes on the link and reduce, then make NewAddCost=0.
When calculating the dilatation cost NewAddCost of link, judge whether link fiber needs the method for dilatation to be: if the residual capacity of existing optical fiber is enough carried the current business demand on the link, then link does not need dilatation; If the residual capacity of existing optical fiber is not enough to carry the current business demand on the link, then link needs dilatation.The choice criteria of the newly-increased optical fiber of dilatation is: choose the optical fiber that capacity is enough and cost is minimum from optical fiber set the inside.
After calculating the dilatation cost NewAddCost of link, calculate the link weight LinkWeight of this link:
LinkWeight=NewAddCost×β+Bw×γ。
Step 2-3: for current business is sought path end to end.After calculating the weight LinkWeight of all links in ten thousand networks, adopting Dijkstra method for routing (being the minimum cost method for routing) is the current business calculating path.For the business of unprotect type, the path that finds a job then is considered as the route success; For the privacy protection type service, find a job simultaneously path and protection path then are considered as the route success.
Usually, the cost in the Dijkstra method for routing equal link weight and node weights and, but in the present invention, in order to simplify calculating, the weight of all nodes is made as 0, promptly do not consider node weights.
Step 2-4: be current business path configurations fiber resource end to end.For the unprotect type service, only be required to be the operating path Resources allocation; For the privacy protection type service, need be operating path and protection path while Resources allocation.During the configuration fiber resource, need for current business end to end each the bar link in the path be configured one by one, during concrete configuration, be configured according to the minimum principle of optic module cost according to the result of calculation of calculating link dilatation cost NewAddCost among the step 2-2.
Step 2-5: current business is deleted current business after the fiber resource configuration in path is finished end to end in collection of services, upgrade collection of services, returns step 2-1 then, professionally seeks route and carries out the fiber resource configuration for next.
Step 3: after the professional fiber resource configuration of all in the collection of services is finished, many optic modules to all links in the network carry out combined optimization, promptly adjust optic modules all on the link and make the total capacity of optic module of this link can carry all business by this link, the cost summation of all optic modules is minimum simultaneously.
Innovative point of the present invention is mainly reflected in following two aspects:
(1) the link weight design mode of multimode blocking and capacity allocation mode.During for professional route, the set-up mode of link cost is the newly-increased cost minimum based on link multimode blocking, but has done some changes in the design, and newly-increased cost is that cost is multiplied by certain factor beta, occurs the unnecessary situation that detours when attempting to avoid professional routing.Simultaneously, also link additional cost and the actual cost that uses are taken all factors into consideration, occurred the unnecessary situation that detours when attempting further to avoid professional routing; During for the traffic assignments resource, in multiple alternative optical fiber rank, select just to satisfy volume of business demand and the most cheap fiber type of cost as far as possible.The processing mode of this multimode makes the utilance of link circuit resource improve greatly.
(2) optical fiber that has disposed on the link is optimized combination.The business configuration process neutralize all business configuration intact after, all inchings that all optical fiber on the link are carried out, mainly realize by following two aspects:
A) merge optical fiber: if a jumbo optical fiber has enough residual capacities can hold the optical fiber of another root low capacity down, then all business on the whole low capacity optical fiber are put into jumbo optical fiber, thereby delete the little optical fiber of this root, reduced cost.
B) reduce the optical fiber specification: a jumbo optical fiber has only been used the part capacity, if be enough to hold traffic carrying capacity in the high-capacity optical fiber with the optical fiber of a low capacity, then under the situation that satisfies the number of fibers restriction on the link, the jumbo optical fiber of this root is replaced the optical fiber that becomes low capacity, reduced cost.
The SDH network planning design method of a kind of multi-modularized optical fiber provided by the invention has been realized under a known network topology (node location and internodal connection situation in the given network) and business demand, the SDHmesh network full dose planning that the link capacity upper limit is not given.Promptly,, optimized the resource of route assignment and LSP, finally made the network link capacity configuration near minimum by weight setting, resource allocation and the multi-modularized optical fiber cost optimization of multimode blocking satisfying under the condition such as the network equipment.
Figure of description
Fig. 1 is the schematic flow sheet of the SDH network planning design method of a kind of multi-modularized optical fiber provided by the invention.
Fig. 2 is the network topology schematic diagram of the specific embodiment of the invention.
Embodiment
With object lesson techniqueflow of the present invention is described below, the link weight when mainly describing professional route is reseted and is put, the combined optimization process between capacity allocation and the multimode blocking, and this is the difficult point and the complicated point of algorithm.The calculating of using in the example is with scheming as shown in Figure 25 summits, 5 links (two-way link).Existing a collection of service needed as shown in table 1 is configured in network topology shown in Figure 2, and alternative optical fiber rank has three kinds of STM-4, STM-16, STM-64, and supposes that their cost is respectively Cost
4=238, Cost
16=364.8, Cost
64=860, calculate the unit cost γ=238/4=59.5 of the most cheap optical fiber.Simultaneously, select dilatation cost coefficient β=10 in this example, it is that this tests a resulting empirical value.
The business demand of table 1 input
Professional numbering |
The service source title |
Professional order title |
Service bandwidth request (M) |
The service protection attribute |
0 |
0 |
1 |
12 |
Unprotect |
1 |
0 |
3 |
8 |
Unprotect |
2 |
3 |
0 |
16 |
Unprotect |
3 |
4 |
0 |
4 |
Unprotect |
In this example, main is research object with the link between node among Fig. 40 and the node 10, and situation is set the weight when introducing professional route in detail on this link and optical fiber is equipped with situation.At first carry out the business ordering, the order of execution is: 2,0,1,3; Be followed successively by professional 2,0,1,3 then and carry out route and fiber resource configuration:
At first computing service 2, because the fiber count that disposes on the link 0 under the initial situation is 0, need increase optical fiber newly during business process link 0, select to satisfy the most cheap fiber type STM-16 of capacity requirement, and the weight that link 0 is set is LinkWeight=Cost
16* β+Bw * γ=346.8 * 10+16 * 59.5=4600.Active link sequence by the dijkstra's algorithm business of calculating 2 is 3-1-0, through link 0, be the optical fiber Fiber0 of a STM-16 of professional 2 configurations on link 0, and the available resources of renewal Fiber0 is 0.
Computing service 0, the capacity of the Fiber0 of configuration is finished using on the link 0, need increase optical fiber newly during business 0 process link 0, selects to satisfy the fiber type STM-16 of capacity requirement, and the weight that link 0 is set is LinkWeight=Cost
16* β+Bw * γ=346.8 * 10+12 * 59.5=4362.Active link sequence by the dijkstra's algorithm business of calculating 2 is 0-1, through link 0, be the optical fiber Fiber1 of a STM-16 of professional 0 configuration on link 0, and the available resources of renewal Fiber1 is 4M.
Computing service 1, the Fiber0 of configuration and the active volume of Fiber1 also have 4M on the link 0, need increase the 4M capacity newly during business 1 process link 0, select to satisfy the fiber type STM-4 of capacity requirement, and the weight that link 0 is set is LinkWeight=Cost
16* β+Bw * γ=238 * 10+8 * 59.5=2856.Being calculated professional 2 active link sequence by dijkstra's algorithm is 0-1-3, through link 0, be the optical fiber Fiber2 of a STM-4 of professional 0 configuration on link 0, and the available resources of renewal Fiber1 are 0, and the available resources of Fiber2 are 0.
Computing service 3, Fiber0, the Fiber1 of configuration and the active volume of Fiber2 also have 0M on the link 0, and the optical fiber that need increase 1 STM-4 during business 3 process links 0 newly can satisfy capacity requirement.But consider on the link 0 be limited on the quantity of configuration STM4 1 and the quantity of STM-16 on be limited to 2, so can only increase the optical fiber Fiber3 of a STM-64 this moment newly.Simultaneously, Fiber0, Fiber1 and Fiber2 can be merged among the Fiber3, promptly only dispose the optical fiber Fiber3 of a STM-64 this moment on the link.The newly-increased cost NewAddCost=(Cost of link 0
64-2 * Cost
16-Cost
4)<0 is updated to 0 with it, and the weight that obtains link 0 is LinkWeight=0+Bw * γ=238.Active link sequence by the dijkstra's algorithm business of calculating 3 is 2-0, through link 0, the optical fiber Fiber3 of a STM-64 of configuration is moved to the business of Fiber0, Fiber1 and Fiber2 among the Fiber3 on link 0 link, with Fiber0, Fiber1 and Fiber2 deletion.Disposed the optical fiber of a STM-64 on the final link, and active volume is updated to 24M.