CN101795462A - Method for realizing measure prediction of network stability by using dynamic stable domain - Google Patents

Abstract

The invention provides a method for realizing measure prediction of network stability by using a dynamic stable domain, and belongs to the technical field of cognitive radio network routing protocols and network performance evaluation. The method comprises the following steps of: establishing a 4-layer evaluation index system of a cognitive radio network routing protocol by utilizing a layering analysis method, wherein the system comprises a target layer, a criterion layer, an index layer and an alternative index layer from the top to the bottom; excavating the evaluation index data of the cognitive radio network routing protocol according to a rough set theory; determining a weight of the evaluation index by combining a knowledge information entropy concept, and lowering subjectivity of weight determination; and based on the combination of basic concepts such as a stable threshold sita, a stability dynamic stable domain delta P of an attribute set and a network stability P, realizing the effective evaluation method for the cognitive radio network routing protocol and the network performance. The method can serve as a good reference for the design and the application of the cognitive radio network routing protocol.

Description

Utilize the predictive metrics method of dynamic stable domain realization to network stability

Technical field

Utilize dynamic stable domain to realize the tolerance and the Forecasting Methodology of network stability are belonged to cognitive radio networks Routing Protocol and network performance evaluation technical field, can use this method network stability is effectively measured and predicted, realize cognitive radio networks Routing Protocol and network performance evaluation.

Background technology

Along with the wireless communication technology develop rapidly, communication system also constantly increases the demand of radio spectrum resources, and rare frequency spectrum resource can't satisfy ever-increasing demand.Can see that from some results of study in recent years frequency spectrum resource lacks more because existing spectrum management and allocation strategy cause.Existing spectrum management and allocation strategy are based on the model of static control mostly; be that management organization becomes fixing, non-overlapped frequency spectrum blocks with the usable spectrum resource division; these frequency spectrum blocks sizes are fixing; and by protecting frequency band to cut apart; these frequency spectrum blocks are distributed to different services and technology in the mode of monopolizing; the user who is assigned to these frequency ranges is called as authorized user (or main user), for example, and mobile communication carrier, radio and television, military affairs and public safety department etc.The method of salary distribution of this static control, spectrum management is very simple, but it is quite low that a large amount of measurement data shows its availability of frequency spectrum, with the U.S. is example, below 3GHz, the utilance of having distributed frequency spectrum in time with the variation from 15% to 85% in geographical position, the frequency spectrum hole on generation time and the space (spectrum hole).In addition, industry, science and medical frequency range (IndustrialScientific and Medical, ISM) also begin to carry out open spectrum utilization strategy, multiple important emerging technology and technological innovation have been brought, yet, because the interference between the multiple heterogeneous network makes that the spectrum efficiency of ISM band neither be too high.

Cognitive radio (Cognitive Radio, CR) be a kind of intelligent radio communication system, by the perception external environment condition, self-adapted adjustment system parameter (as relevant parameters such as through-put power, carrier frequency and modulation techniques) changes to adapt to external environment condition, authorized user and cognitive user (being unauthorized user) are not being produced under the prerequisite of harmful interference, dynamically insert idle frequency spectrum in the chance mode, improve the availability of frequency spectrum.The appearance of cognitive radio technology provides strong technical support for solving the frequency spectrum resource deficiency, realize the frequency spectrum dynamic management and improving the availability of frequency spectrum.

Route is CR network (CR networks, CRNET) one of key technology, the CRNET route is for improving network connectivty, it is significant further to promote network performance, simultaneously, can make up the evaluation of CRNET overall performance of network by the evaluation of CRNET route, the present invention just is being based on this thinking, define the notion of CRNET network stability and dynamic stable domain dexterously by the result of relevant performance of route protocol evaluation, and then proposed a kind of tolerance and Forecasting Methodology of utilizing the dynamic stable domain realization to network stability.

The problem that the CRNET route faces has: because CRNET adopts dynamic spectrum to insert, and its usable spectrum is unfixed, has dynamic and diversity, cause node to connect and have intermittence on the one hand; CR user need take interference avoidance strategy on the other hand, prevents to cause interference to threaten to main user.The problems referred to above make the Routing Protocol of conventional wireless multihop network can't be applicable to effectively among the CRNET that the CRNET route faces new challenges.Along with the research of CR is goed deep into, the Routing Protocol and the algorithm of many Different Strategies have been proposed in recent years, comprise that total thinking is that route and frequency spectrum are selected co-design based on striding layer route of design, frequency spectrum perception route, multipath high usage route, location-based sub-clustering route etc. as required.The progress that obtains than the research of CRNET route then is in the starting stage about the research of CRNET routing performance evaluation method, does not also form a kind of effectively evaluating standard at present.Quality by objective, comprehensive performance evaluation is come more various Routing Protocols has great importance and reference value for selection, optimization and the design of high usage route agreement and the raising of CRNET performance.Further, the evaluation study of CRNET overall performance of network is in the starting stage equally, and research CRNET network performance evaluation method has certain reference value for improving network performance.

Summary of the invention

The present invention constructs a kind of tolerance and Forecasting Methodology of utilizing the dynamic stable domain realization to network stability, and purpose is to realize cognitive radio networks Routing Protocol and network performance evaluation.

The invention provides a kind of solution for the overall evaluation of cognitive radio networks performance.Its core is to have proposed a kind of CRNET Routing Protocol comprehensive performance evaluation method based on rough set, define the basic conception of cognitive radio networks stability and dynamic stable domain on this basis, and further provided the tolerance and the Forecasting Methodology of network stability.

CRNET Routing Protocol comprehensive performance evaluation strategy adopts analytic hierarchy process (AHP) to propose a kind of CRNET Routing Protocol assessment indicator system, and evaluation index quantized and analyze, on this basis, propose among a kind of CRNET based on rough set the Routing Protocol integrated evaluating method (rough set approach to comprehensive performance evaluation of routingprotocols, RSACERP).This method adopts rough set (rough set) theory that the evaluation index data of CRNET Routing Protocol are excavated, adopt the comentropy notion of knowledge, evaluation index Weight Determination problem is converted into the attribute importance problem of computing information system, by to attribute importance normalized, thereby determine the weight of evaluation index.Experimental result shows that the RSACERP method has feasibility and validity.CRNET network performance evaluation strategy has been set up the relation between network stability and CRNET Routing Protocol comprehensive performance evaluation value, has proposed the tolerance and the Forecasting Methodology of network stability.

Its steps in sequence is as follows:

Step 1: set up assessment indicator system (as shown in Figure 1);

Step 2: evaluation index is quantized and qualitative analysis;

Step 3: determine each index weight;

Step 4: determine to stablize thresholding Θ;

Step 5: to the stability under single community set

Measure;

Step 6: determine dynamic stable domain Δ P and network stability P.

Experimental results show that: the present invention can effectively realize the performance evaluation to cognitive radio networks Routing Protocol and network, reflects the performance of its Routing Protocol.

Description of drawings

Fig. 1 is for using the CRNET Routing Protocol assessment indicator system that the present invention makes up.

Fig. 2 is for using Routing Protocol overall merit information table IS of the present invention ₁

Fig. 3 is for using Routing Protocol overall merit information table IS of the present invention ₂

Fig. 4 is for using Routing Protocol overall merit information table IS of the present invention ₃

Fig. 5 is for using Routing Protocol overall merit information table IS of the present invention ₄

Fig. 6 is of the present invention by information table IS for using ₁6 kinds of Routing Protocol comprehensive evaluation values that obtain.

Fig. 7 is of the present invention by information table IS for using ₂6 kinds of Routing Protocol comprehensive evaluation values that obtain.

Fig. 8 is of the present invention by information table IS for using ₃6 kinds of Routing Protocol comprehensive evaluation values that obtain.

Fig. 9 is of the present invention by information table IS for using ₄6 kinds of Routing Protocol comprehensive evaluation values that obtain.

Figure 10 utilizes tolerance and the Forecasting Methodology procedure chart of dynamic stable domain realization to network stability

Embodiment

About the detailed step and the correlation technique implementation method of this invention, existing accompanying drawings is as follows.

The main task of CRNET Routing Protocol is to produce, safeguard and select route between source node and destination node, and according to the routing forwarding packet of selecting, guarantees the connectivity of network.The target of Routing Protocol design should satisfy demands of applications, and it is accurate, quick and efficient to require simultaneously.RFC2501 has provided the quantizating index that is used to estimate general performance of route protocol, comprises throughput, end-to-end time delay, route settling time, the out-of-sequence ratio of data packet transmission, efficient etc.The present invention is directed to the basic characteristics of CRNET and the problem that route faces thereof, suggestion according to RFC2501, analysed in depth the leading indicator that influences the CRNET performance of route protocol, adopt analytic hierarchy process (AHP) that each index is assembled combination with index by different levels according to interrelated influence between index and membership, set up the feasible multi-level assessment indicator system of CRNET Routing Protocol of a cover.This index system is divided into 4 layers of destination layer, rule layer, indicator layer and alternative indicator layers, and wherein rule layer is with functional (η ₁), practicality (η ₂), applicability (η ₃) and autgmentability (η ₄) be the one-level evaluation index, constitute set of criteria Δ={ η ₁, η ₂, η ₃, η ₄, indicator layer comprises 18 secondary evaluation indexes that the refinement of one-level evaluation index is produced, as shown in Figure 1.For the fail safe of portrayal Routing Protocol, introduce alternative indicator layer, the safety indexes in the applicability is constituted alternative index set Ξ={ β ₁..., β ₅, comprise 5 alternative indexs.In actual applications, can be according to the characteristics of application demand and overall merit, this assessment indicator system is expanded and adjusts.

Assessment indicator system middle finger target quantizes for the confidence level that improves the Routing Protocol evaluation most important, and the evaluation index that is difficult to quantize adopts scientific and reasonable qualitative analysis to reduce subjectivity and the one-sidedness of estimating.

(1) functional is the additional capabilities that Routing Protocol is finished generation, maintenance and selected to have outside the route, and its quantizating index is function index F, is expressed as

F＝MUPA+QOS+MUCA+LOFR (1)

Wherein MUPA, QOS, MUCA, LOFR are respectively multipath index support, QoS index support, multicast index support, loop and avoid index, and the index value is that 0 or 1,0 expression is not supported or do not had corresponding function, and 1 expresses support for corresponding function.

(2) practicality is the satisfaction of Routing Protocol to actual demand and application.End-to-end time delay D _RouteThe time delay summation of representing each jumping on the end-to-end route, by node time delay D N and the path delay of time DP form i.e. D _Route=DN+DP.Because switching, frequency spectrum causes handover delay D _Switch, to being in the node on the same channel, produce concealed terminal and exposed terminal problem, keep out of the way time delay D thereby introduce _BackoffIn addition, have intermittence, thereby produce queuing delay D because node connects _Queue, so DN and DP can be quantified as

$\left\{\begin{array}{c}\mathrm{DN}=D_{\mathrm{switch}}+D_{\mathrm{backoff}}+D_{\mathrm{queue}}\\ \mathrm{DP}=D_{\mathrm{switch}}+D_{\mathrm{backoff}}+D_{\mathrm{trans}}\end{array}\right.---\left(2\right)$

D wherein _TransBe the propagation delay time of bringing in the packet repeating process.Relevant D _SwitchAnd D _BackoffBut calculating list of references (Cheng G, Liu W, Li Y, et al.Joint on-demand routing and spectrum assignment in cognitiveradio networks.In:Proceedings of IEEE ICC ' 07, Glasgow, 2007:6499-6503).For CRNET, the length of jumping figure often opposite end plays a crucial role to terminal delay time, supposes to contain k CR node altogether from the source node to the destination node, and then jumping figure HOP can be quantified as HOP=k-1.

Owing to reasons such as node queue overflows, routing failures, adopt data packet transmission rate P _AcceptedThe probability that the expression packet successfully receives is with the reflection router efficiency, promptly

$P_{\mathrm{accepted}}=\underset{T}{\mathrm{\Σ}}{\mathrm{NUM}}_{\mathrm{acpt}}/\underset{T}{\mathrm{\Σ}}{\mathrm{NUM}}_{\mathrm{trans}}---\left(3\right)$

NUM wherein _AcptBe the packet that source node sent in the unit interval, NUM _TransBe the packet that destination node received in the unit interval, T is the time interval.

Throughput THR has reflected the efficient of forwarded packet, supposes that it is hop (i) that route i jumps, and it is B that usable spectrum b goes up bandwidth _{W, b}, the time that node did not send or received packet is T _{F, b}, then the throughput of the last hop (i) of frequency spectrum b is Thr _{Hop (i), b}=T _{F, b}* B _{W, b}* P _Accepted, then THR is the adding up of throughput of all jumpings between source node and destination node, promptly

$\mathrm{THR}={\mathrm{\Σ}}_{i=1}^{\mathrm{HOP}}{\mathrm{Thr}}_{\mathrm{hop}\left(i\right),b}---\left(4\right)$

Suppose that the received power of intermediate node j on frequency spectrum b is P _{R, j} ^b, the interference that main user introduces is P _{I, j} ^b(can be estimated by logarithm normal distribution), the one-sided power spectrum density of AWGN is N ₀, then the capacity of hop (i) is

${\mathrm{CAP}}_i=B_{w,b}\×{\log }_2[1+P_{r,j}^b/(N_0+P_{I,j}^b)]---\left(5\right)$

Then capacity C AP is CAP=min{CAP _i, i=1,2 ..., k-1.

(3) applicability be Routing Protocol under regular service conditions, satisfy the ability of predetermined instructions for use.Routing Protocol should be taken routing energy consumption and network energy expending equilibrium into consideration, with energy consumption E _ConBe quantified as

$E_{\mathrm{con}}={\mathrm{\Σ}}_{j=1}^k{E}_{\mathrm{con}}^j={\mathrm{\Σ}}_{j=1}^k(E_{\mathrm{Rx}}^j+E_{\mathrm{Tx}}^j+E_{\mathrm{Pr}}^j)---\left(6\right)$

E wherein _Pr ^jFor handling energy consumption, E _Rx ^jAnd E _Tx ^jBe respectively and receive energy consumption, send energy consumption, but its computational methods list of references (Heinzelman W R, Chandrakasan A, Balakrishnan H.Energy-efficient communication protocolfor wireless microsensor networks[C] .In:Proceedings ofHICSS ' 00, Maui, Hawaii, 2000).

Route control expense OH _ControlBe described as control data bag (the note N of each node transmission in the path _Ontrol ^j) the total packet sum that receives with destination node (note N _Total ^D) ratio, promptly

Protocol overhead OH _ProBe described as route (note T settling time _Setup) and dismounting time (note T _Teardown) sum, i.e. OH _Pro=T _Setup+ T _Teardown

Computational complexity has been portrayed the complexity of the computer solving of routing algorithm, from time complexity O (f (n)) the route algorithm is estimated, and sets thresholding O (f ₀(n)), at the time complexity O of algorithm (f (n))≤O (f ₀(n)) under the condition, carry out complexity and relatively sort, computational complexity grade CMPX is set.

Fail safe is the security threat that faces at Routing Protocol, adopts security mechanism to guarantee the safe coefficient of routing iinformation.Routing Protocol need satisfy demands for security such as availability, confidentiality, data integrity, authentication and non-repudiation, can and be easy to realization property from safe class, functional, mode of operation, security performance usually demand for security is estimated.The present invention is quantified as fail safe SEC from the demand for security angle

SEC＝AVA+CON+INT+AUT+NRE (7)

Wherein AVA, CON, INT, AUT, NRE are respectively availability indexes, confidentiality index, data integrity sex index, the undeniable sex index of authentication exponential sum, and the index value is that 0 or 1,0 expression does not provide or do not have respective capabilities, and 1 expression provides respective capabilities.

(4) autgmentability is adaptation, transplanting and the extended capability of Routing Protocol.Introduce applicable network scaled index Y, be described as the node number that unit are has in the network, suppose that main number of users is p in the network, area is S, then Y=(p+k)/S.Expansion index SCA is described as upgradability, compatibility and the interoperability ability that Routing Protocol has, and is expressed as

S＝UG+CP+OP (8)

Wherein UG, CP, OP are respectively upgrading index, compatible exponential sum interoperability index, and the index value is that 0 or 1,0 expression is not supported or do not had respective capabilities, and 1 expresses support for respective capabilities.

(V f) is information system, wherein a U={x for U, C to define 1 four-tuple IS= ₁, x ₂..., x _pClose for the nonempty finite set of object, be called domain; C={ α ₁, α ₂..., α _qClose for the nonempty finite set of attribute;

Be attribute α _iCodomain ,-1,2 ..., q, promptly

F:U * C → V is an information function, makes

x _j∈ U, j=1,2 ..., p has

It is a domain that U is established in definition 2, and P and Q are two equivalence relations bunch (being knowledge) on the U.The division that P and Q derive on U is respectively X and Y, wherein X=U/IND (P)={ X ₁, X ₂..., X _n, Y=U/IND (Q)={ Y ₁, Y ₂..., Y _m, then P and the Q probability distribution on the σ algebraically that the subclass of U is formed is

$[X;p]=\left[\begin{array}{cccc}{X}_1& {\mathrm{<figure-callout\; id="2"\; label="X"\; filenames="H2010100340927E00012.png,H2010100340927E00013.png"\; state="\{\{state\}\}">X</figure-callout>}}_2& ...& X_n\\ p\left(X_1\right)& p\left(X_2\right)& ...& p\left(X_n\right)\end{array}\right]$

$[Y;p]=\left[\begin{array}{cccc}{Y}_1& {\mathrm{<figure-callout\; id="2"\; label="Y"\; filenames="H2010100340927E00012.png,H2010100340927E00013.png"\; state="\{\{state\}\}">Y</figure-callout>}}_2& ...& Y_m\\ p\left(Y_1\right)& p\left(Y_2\right)& ...& p\left(Y_m\right)\end{array}\right]$

P (X wherein _i)=card (X _i)/card (U), i=1,2 ..., n, p (Y _j)=card (Y _j)/card (U), j=1,2 ..., m, the radix of symbol card (E) expression set E, then the comentropy H (P) of knowledge (community set) P is

$H\left(P\right)=-\underset{i=1}{\overset{n}{\mathrm{\&Sigma;}}}p\left(X_i\right)\log p\left(X_i\right)---\left(9\right)$

IS=is established in definition 3, and (V f) is an information system, attribute α for U, C _i∈ C (i=1,2 ..., q) importance for community set C is

SGF _C(α _i)＝|H(C)-H(C-{α _i})| (10)

And SGF _C(α _i) character have: if SGF _C(α _i)＞0, then α _iBe necessary in C; If SGF _C(α _i)=0, then α _iBe redundant in C, can be by yojan.

According to definition 3, to attribute importance SGF _C(α _i) do normalized, can obtain the weight of CRNET Routing Protocol evaluation index (attribute), promptly

${\mathrm{\&omega;}}_i={\mathrm{SGF}}_C\left({\mathrm{\&alpha;}}_i\right)/\underset{l=1}{\overset{q}{\mathrm{\&Sigma;}}}{\mathrm{SGF}}_C\left({\mathrm{\&alpha;}}_l\right),l=\mathrm{1,2},...q---\left(11\right)$

The step of RSACERP method is as follows:

Step 1: set up assessment indicator system (as shown in Figure 1).

Step 2: the domain of determining comment.Adopt 3 grades of comment grades, the domain of comment is ψ={ good, better, general }, is respectively 3,2,1 accordingly.

Step 3: set up information table J=1,2,3,4.The present invention estimates the CRNET Routing Protocol by class by the element in the Δ (one-level evaluation index) from the angle of set of criteria Δ.The individual CRNET Routing Protocol of λ to be evaluated (λ 〉=1) is constituted domain U={x ₁..., x _λ, the secondary evaluation index under the one-level evaluation index in the Δ is constituted community set according to from left to right order in the assessment indicator system:

Each element among the U is carried out quantification treatment and qualitative analysis by evaluation index respectively, quantized result is compared, and it is right to press ψ by the colleague expert In evaluation index mark one by one, obtain attribute

(i=1,2 ..., 18) evaluation of estimate

Thereby the codomain V of configuration information function f.

Step 4: press community set

Calculate the weight (calculating the weight of evaluation index by formula (9), (10) and (11)) of evaluation index by class.

Step 5: the overall merit conclusion that obtains to divide attribute.According to community set The comprehensive evaluation value of r CRNET Routing Protocol is calculated as follows

Wherein

Then, can determine that r CRNET Routing Protocol divides the overall merit conclusion of attribute, thereby can divide the attribute comparison of sorting λ Routing Protocol according to the domain ψ of comment.

Whether the application of alternative indicator layer depends on whether the CRNET Routing Protocol has adopted security mechanism, then estimates according to the RSACERP method from alternative indicator layer angle if adopt.

Be validity and the feasibility of checking RSACERP method in the CRNET performance of route protocol is estimated, the present invention chooses the SORP agreement and the DORP agreement experimentizes, and the former is (x ₁) adopt based on the frequency spectrum perception of multi-hop CRNET routing cross-layer co-design strategy as required, the latter (x ₂) be a kind of on-demand routing protocol based on the time delay module, adopt route and the mutual strategy of frequency spectrum scheduling associating as required.The characteristics of the two are 1. to adopt improved on-demand routing protocol AODV to realize exchanging spectrum opportunities collection (spectrum opportunities, SOP) message between node on Common Control Channel; 2. adopt the main evaluation index of end-to-end accumulation time delay as agreement.The deficiency of the two is that agreement lacks security mechanism.The present invention simultaneously chooses AODV agreement (x in the Ad Hoc network ₃) and DSR agreement (x ₄), and introduce other two kinds of routing policies according to document and compare: a kind of is " avoiding switching (Switch-aware) " routing policy (x that reduces the frequency range switching times and switch frequent degree ₅); Another kind is that K jumping interior nodes distributes separate frequency bands to keep out of the way " K jumps independently (K-hop distinct) " routing policy (x to reduce conflict ₆).Therefore can set up domain U={x ₁, x ₂, x ₃, x ₄, x ₅, x ₆.

The present invention adopts assessment indicator system as shown in Figure 1, estimates by class from the angle of set of criteria Δ, because above-mentioned 6 kinds of Routing Protocols are not considered security mechanism, historical facts or anecdotes is tested and do not adopted alternative indicator layer.With the secondary evaluation index under the one-level evaluation index in the Δ according to 4 community sets of RSACERP method construct With

6 kinds of Routing Protocols are pressed respectively

In evaluation index carry out quantification treatment and qualitative analysis, and on the NS2 emulation platform validity of evaluation index of 6 kinds of Routing Protocols of checking, right by the colleague expert by the domain ψ of comment In evaluation index mark one by one, thereby set up 4 information table IS _j, shown in Fig. 2,3,4,5.

For information table IS ₁, because

So attribute α ₃Can be by yojan, the weight that can obtain all the other 3 attributes is respectively ω ₁=0.2393, ω ₂=0.2393, ω ₄=0.5214, thus the comprehensive evaluation value of 6 kinds of Routing Protocols can be got, as shown in Figure 6.

For information table IS2, because

So attribute α ₇, α ₈Can be by yojan, the weight that can obtain all the other 3 attributes is respectively ω ₅=ω ₆=ω ₉=0.3333, thus the comprehensive evaluation value of 6 kinds of Routing Protocols can be got, as shown in Figure 7.

For information table IS ₃, because

So attribute α ₁₄Can be by yojan, the weight that can obtain all the other 4 attributes is respectively ω ₁₀=0.4000, ω ₁₁=ω ₁₂=ω ₁₃=0.2000, thus the comprehensive evaluation value of 6 kinds of Routing Protocols can be got, as shown in Figure 8.

For information table IS ₄, because

So attribute α ₁₅Can be by yojan, the weight that can obtain all the other 3 attributes is respectively ω ₁₆=ω ₁₈=0.2500, ω ₁₇=0.5000, thus the comprehensive evaluation value of 6 kinds of Routing Protocols can be got, as shown in table 8.

Definition 4 is stablized thresholding Θ and is kept stablizing required lowest threshold for the CRNET network.

Define 5 community sets

Stability For

$P_{{\mathrm{\&eta;}}_j}=\frac{\mathrm{\&Theta;}}{W_r},$ j＝1，2，3，4 (13)

W wherein _rFor at community set

Under the comprehensive evaluation value of r CRNET Routing Protocol.

Define 6 dynamic stable domain Δ P for interval

$\mathrm{\&Delta;P}=[0,\underset{j}{\mathrm{\&Pi;}}{P}_{{\mathrm{\&eta;}}_j}+\mathrm{\&Theta;}],j=\mathrm{1,2,3,4}---\left(14\right)$

And if only if

The time, network enters stable state.

Defining 7 network stability P is

$P=\underset{j}{\mathrm{\&Pi;}}{P}_{{\mathrm{\&eta;}}_j},$ j＝1，2，3，4 (15)

Wherein P is more little, and network stability is big more, and then overall performance of network is just good more.

What the present invention proposed utilizes the dynamic stable domain realization as follows to the tolerance and the Forecasting Methodology of network stability:

Step 1: set and stablize thresholding Θ and the individual CRNET Routing Protocol of λ (λ 〉=1) to be evaluated.

Step 2: according to community set

Calculate the comprehensive evaluation value of r CRNET Routing Protocol.

Step 3: computation attribute set

Stability

Thereby determine dynamic stable domain Δ P and network stability P.

Step 4: according to the big or small evaluating network overall performance of network stability P.

Claims (1)

1. utilize the predictive metrics method of dynamic stable domain realization, it is characterized in that network stability:

1) foundation of assessment indicator system

Assessment indicator system is divided into 4 layers of destination layer, rule layer, indicator layer and alternative indicator layers, and wherein rule layer is with functional (η ₁), practicality (η ₂), applicability (η ₃) and autgmentability (η ₄) be the one-level evaluation index, constitute set of criteria Δ={ η ₁, η ₂, η ₃, η ₄, indicator layer comprises the quantification and the qualitative analysis of the evaluation index in 18 secondary evaluation indexes that the refinement of one-level evaluation index is produced; Safety indexes in the applicability is constituted alternative index set Ξ={ β ₁..., β ₅, comprise 5 alternative indexs;

2) quantification of evaluation index and qualitative analysis

(1) functional is the additional capabilities that Routing Protocol is finished generation, maintenance and selected to have outside the route, its quantizating index is function index F, be expressed as F=MUPA+QOS+MUCA+LOFR, wherein MUPA, QOS, MUCA, LOFR are respectively multipath index support, QoS index support, multicast index support, loop and avoid index, the index value is 0 or 1,0 expression does not support or does not have corresponding function that 1 expresses support for corresponding function;

(2) practicality is the satisfaction of Routing Protocol to actual demand and application; End-to-end time delay D _RouteThe time delay summation of representing each jumping on the end-to-end route, by node time delay D N and the path delay of time DP form, be D _Route=DN+DP; Because switching, frequency spectrum causes handover delay D _Switch,, produce concealed terminal and exposed terminal problem, thereby time delay D occurs keeping out of the way being in the node on the same channel _BackoffIn addition, have intermittence, thereby produce queuing delay D because node connects _Queue, so DN and DP can be quantified as $\left\{\begin{array}{c}\mathrm{DN}=D_{\mathrm{switch}}+D_{\mathrm{backoff}}+D_{\mathrm{queue}}\\ \mathrm{DP}=D_{\mathrm{switch}}+D_{\mathrm{backoff}}+D_{\mathrm{trans}}\end{array}\right.,$ D wherein _TransBe the propagation delay time of bringing in the packet repeating process;

For CRNET, the length of jumping figure often opposite end plays a crucial role to terminal delay time, supposes to contain k CR node altogether from the source node to the destination node, and then jumping figure HOP can be quantified as HOP=k-1;

Because node queue overflows, routing failure, adopt data packet transmission rate P _AcceptedThe probability that the expression packet successfully receives then has with the reflection router efficiency

NUM wherein _AcptBe the packet that source node sent in the unit interval, NUM _TransBe the packet that destination node received in the unit interval, T is the time interval;

Throughput THR has reflected the efficient of forwarded packet, establishes route i jumping and is hop (i), and it is B that usable spectrum b goes up bandwidth _{W, b}, the time that node did not send or received packet is T _{F, b}, then the throughput of the last hop (i) of frequency spectrum b is Thr _{Hop (i), b}=T _{F, b}* B _{W, b}* P _Accepted, then THR is the adding up of throughput of all jumpings between source node and destination node, has

When the received power of intermediate node j on frequency spectrum b is P _{R, j} ^b, the interference that main user introduces is P _{I, j} ^b, P wherein _{I, j} ^bCan estimate that the one-sided power spectrum density of AWGN is N by logarithm normal distribution ₀, then the capacity of hop (i) is Then capacity C AP is CAP=min{CAP _i, i=1,2 ..., k-1;

(3) applicability be Routing Protocol under regular service conditions, satisfy the ability of predetermined instructions for use; Routing Protocol should be taken routing energy consumption and network energy expending equilibrium into consideration, with energy consumption E _ConBe quantified as

E wherein _Pr ^jFor handling energy consumption, E _Rx ^jAnd E _Tx ^jBe respectively and receive energy consumption, send energy consumption;

Route control expense OH _ControlBe described as the control data bag sum N of each node transmission in the path _Control ^jPacket sum N with the destination node reception _Total ^DRatio,

Protocol overhead OH _ProBe described as route T settling time _SetupWith the dismounting time T _TeardownSum, OH _Pro=T _Setup+ T _TeardownComputational complexity has been portrayed the complexity of the computer solving of routing algorithm, from time complexity O (f (n)) the route algorithm is estimated, and sets thresholding O (f ₀(n)), at the time complexity O of algorithm (f (n))≤O (f ₀(n)) under the condition, carry out complexity and relatively sort, computational complexity grade CMPX is set;

From the demand for security angle fail safe SEC is quantified as SEC=AVA+CON+INT+AUT+NRE, wherein AVA, CON, INT, AUT, NRE are respectively availability indexes, confidentiality index, data integrity sex index, the undeniable sex index of authentication exponential sum, the index value is 0 or 1,0 expression does not provide or does not have respective capabilities, and 1 expression provides respective capabilities;

(4) autgmentability is adaptation, transplanting and the extended capability of Routing Protocol.Introduce applicable network scaled index Y, be described as the node number that unit are has in the network, suppose that main number of users is p in the network, area is S, then Y=(p+k)/S; Expansion index SCA is described as upgradability, compatibility and the interoperability ability that Routing Protocol has, be expressed as S=UG+CP+OP, wherein UG, CP, OP are respectively upgrading index, compatible exponential sum interoperability index, the index value is 0 or 1,0 expression does not support or does not have respective capabilities that 1 expresses support for respective capabilities;

3) index Weight Determination

(V f) is information system, wherein a U={x to four-tuple IS=for U, C ₁, x ₂..., x _pClose for the nonempty finite set of object, be called domain; C={ α ₁, α ₂..., α _qClose for the nonempty finite set of attribute;

Be attribute α _iCodomain, i=1,2 ..., q, Be information function, make

Have

If U is a domain, P and Q are two equivalence relations bunch on the U; The division that P and Q derive on U is respectively X and Y, wherein X=U/IND (P)={ X ₁, X ₂..., X _n, Y=U/IND (Q)={ Y ₁, Y ₂..., Y _m, then P and the Q probability distribution on the σ algebraically that the subclass of U is formed is

$[X;p]=\left[\begin{array}{cccc}{X}_1& X_2& ...& X_n\\ p\left(X_1\right)& p\left(X_2\right)& ...& p\left(X_n\right)\end{array}\right]$

$[Y;p]=\left[\begin{array}{cccc}{Y}_1& Y_2& ...& Y_m\\ p\left(Y_1\right)& p\left(Y_2\right)& ...& p\left(Y_m\right)\end{array}\right]$

P (X wherein _i)=card (X _i)/card (U), i=1,2 ..., n, p (Y _j)=card (Y _j)/card (U), j=1,2 ..., m, the radix of symbol card (E) expression set E, then the comentropy H (P) of knowledge (community set) P is $H\left(P\right)=-\underset{i=1}{\overset{n}{\mathrm{\&Sigma;}}}p\left(X_i\right)\log p\left(X_i\right);$

IS=is established in definition 3, and (V f) is an information system, attribute α for U, C _i∈ C (i=1,2 ..., q) importance for community set C is SGF _C(α _i)=| H (C)-H (C-{ α _i) |.And SGF _C(α _i) character have: if SGF _C(α _i)＞0, then α _iBe necessary in C; If SGF _C(α _i)=0, then α _iBe redundant in C, can be by yojan;

To attribute importance SGF _C(α _i) do normalized, can obtain the weight of CRNET Routing Protocol evaluation index (attribute), promptly ${\mathrm{\&omega;}}_i={\mathrm{SGF}}_C\left({\mathrm{\&alpha;}}_i\right)/\underset{l=1}{\overset{q}{\mathrm{\&Sigma;}}}{\mathrm{SGF}}_C\left({\mathrm{\&alpha;}}_l\right),l=\mathrm{1,2},...,q;$

4) stablize determining of thresholding

Stable thresholding is defined as the CRNET network and keeps stablizing required lowest threshold;

5) tolerance of the stability under single community set

Community set

Stability be defined as W wherein _rFor at community set

Under the comprehensive evaluation value of r CRNET Routing Protocol;

6) dynamic stable domain and network stability determines

Dynamic stable domain Δ P is interval

And if only if

The time, network enters stable state;

Network stability P is

Wherein P is more little, and network stability is big more, and then overall performance of network is just good more.

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