CN103326822B - Based on participatory sensory perceptual system method for secret protection and the system of data fragmentation - Google Patents

Abstract

A kind of participatory sensory perceptual system method for secret protection based on data fragmentation of field of information security technology and system, raw sensed data are obtained by mobile device, correcting and eleting codes is adopted to carry out a point slice encode to initial data, then the mobile device user mark after hash function encryption and the data slice after point slice encode being carried out asymmetric data encryption, producing the enciphered data sheet for transmitting; Enciphered data sheet retained a slice and remainder data sheet and surrounding user are exchanged, and transmitting all enciphered data sheets to server after exchange; Last server passes through after receiving enciphered data sheet to build the reconstruct of data slice table realization to initial data.The present invention is directed to privacy of user protection problem in the middle of participatory sensory perceptual system; adopt and raw sensed data (especially for multi-medium data) are carried out to a point slice encode, exchanged the thought of transmission; data slice is sent to service provider's (server end); reach the object of secret protection; this mechanism enhances System Fault Tolerance performance simultaneously, reduces overhead.

Description

Based on participatory sensory perceptual system method for secret protection and the system of data fragmentation

Technical field

What the present invention relates to is a kind of method and system of field of information security technology, specifically a kind of participatory sensory perceptual system method for secret protection based on data fragmentation and system.

Background technology

Participatory sensory perceptual system (ParticipatorySensingSystems) refers to utilize the built-in sensors part of numerous mobile communication equipment to carry out the new types of data service mode of the perception of data, collection, analysis and feedback application.Along with the development of the communication technology, sensor technology and mobile device technology, the handheld mobile device of embedded numerous perception device is popularized rapidly, makes participatory sensory perceptual system become current study hotspot thus.It mainly faces two hang-ups: one is the private data guard problem of participating user: perception data usually all can be with have living space, the information such as time, if be directly sent to service provider by perception user, easy leakage active user privacy, such as identity information, family and job site, tourism route or even life style and custom etc., otherwise, privacy information cannot be effectively protected directly will affect the participation enthusiasm of participant, hinders the development of participatory sensory perceptual system; Two is lack the participatory perception for multimedia data type, such as, there is a lot of problem to the acquisition of video, audio frequency and image, transmission and process.

Based on above observation; the present invention proposes a kind of based on data fragmentation coding, the privacy information protection mechanism exchanging transmission thought; this mechanism is applicable to participatory sensory perceptual system; particularly for multimedia data type, there is good secret protection effect; simultaneously; this mechanism can improve the fault freedom of entire system greatly, reduces the overhead of mobile device.

Through finding the retrieval of prior art, Chinese patent literature CN101808095, publication date 2010-08-18, disclose the encryption copy organization method under a kind of distributed storage environment, management unit's data block of system data is divided into multiple equal and opposite in direction data segment, system still manages in units of block, and client is encrypted data in units of data segment, so just can provide more fine-grained control to data block.Because data block is segmented encryption, therefore not there is correlation between each encrypt data section, can by the encryption and decryption walked abreast, the read-write avoiding small data quantity just carries out to whole data block the great expense incurred that encryption and decryption brings; Reading for big data quantity, divides into groups read request, and what different grouping requests walked abreast is sent to each memory node that maintain requested file data blocks copy, and each grouping of parallel reading, improves the efficiency of read data.This technology achieves application encipher technology and Replication technology under distributed storage environment, and the encryption copy organization method proposed greatly improves the efficiency read and write data.But this technology be based under distributed storage environment, be applicable to a kind of cryptographic means of large quantity, but for have high mobility, low data-handling capacity, small data quantity participatory sensory perceptual system be completely inapplicable.

Summary of the invention

The present invention is directed to the deficiency that prior art exists; a kind of participatory sensory perceptual system method for secret protection based on data fragmentation and system are proposed; for privacy of user protection problem in the middle of participatory sensory perceptual system; adopt and raw sensed data (especially for multi-medium data) are carried out to a point slice encode, exchanged the thought of transmission; data slice is sent to service provider's (server end); reach the object of secret protection; this mechanism enhances System Fault Tolerance performance simultaneously, reduces overhead.

The present invention is achieved by the following technical solutions:

The present invention relates to a kind of participatory sensory perceptual system method for secret protection based on data fragmentation, comprise the following steps:

The first step, obtain raw sensed data by mobile device, correcting and eleting codes is adopted to carry out a point slice encode to initial data, then the mobile device user mark after hash function encryption and the data slice after point slice encode being carried out asymmetric data encryption, producing the enciphered data sheet for transmitting.

Second step, the enciphered data sheet that the first step generates retained a slice and remainder data sheet and surrounding user exchanged, and transmitting all enciphered data sheets to server after exchange.

Described exchange comprises: meet exchange and minimum cost exchange.

Described exchange of meeting refers to: its enciphered data sheet is sent to other users run in moving process by the owner successively, until enciphered data sheet life cycle terminates, then periodically sends to server by the user receiving enciphered data sheet.

Described minimum cost exchanges and refers to: under the prerequisite ensureing overhead little as far as possible, choose enciphered data sheet exchangeable object, be namely located in enciphered data sheet life cycle, user a _i∈ N can be with | N (a _i) | individual user meets, for each user a that will meet _j∈ N (a _i), p (a _j) represent a _jwith a _icollision probability, c (a _j) represent a _jwith a _iexchange the overhead born required for a slice data.

Described collision probability p (a _j) and overhead c (a _j) obtained by historical data and mobility prediction model.

Described mobility prediction model refers to: for each user a _j∈ N (a _i), ensureing, under overhead prerequisite little as far as possible, to choose a subset as the relay transmission node of its enciphered data sheet, and meet any one condition below:

Condition 1: require at least to run into m-1 user (problem meeting this condition is referred to as MCT-EXP problem), namely meet:

Objective： $min\underset{a_j\∈N\left(a_i\right)}{\Σ}c\left(a_j\right)p\left(a_j\right)x_j$

Subjectto： $\underset{a_j\∈N\left(a_i\right)}{\Σ}p\left(a_j\right)x_j\≥m-1,---\left(1\right);$

$x_j\∈\{0,1\},\∀a_j\∈N\left(a_i\right)---\left(2\right).$

Above-mentioned constraints (1) ensure that user a _i∈ N at least runs into m-1 other users, and constraints (2) represents x _jspan, x _j=1 represents a _jbe chosen as exchangeable object, otherwise then represent not selected.

Condition 2: require that the probability running at least m-1 user is at least P, 0≤P≤1 (problem meeting this condition is referred to as MCT-PRO problem), namely meets:

Objective： $\min \frac{\underset{\stackrel{\→}{y}:\underset{a_k\∈N\left(a_i\right)}{\Σ}{x}_k{y}_k=m-1}{\Σ}\left(\underset{a_j\∈N\left(a_i\right)}{\Σ}\right(c\left(a_j\right)x_j{y}_j\left)\underset{a_j\∈N\left(a_i\right)}{\Π}p{\left(a_j\right)}^{y_j}\right)}{\underset{\stackrel{\→}{y}:\underset{a_k\∈N\left(a_i\right)}{\Σ}{x}_k{y}_k=m-1}{\Σ}\underset{a_j\∈N\left(a_i\right)}{\Π}p{\left(a_j\right)}^{y_j}};$

Subjectto： $\underset{t=m-1}{\overset{\underset{a_k\∈N\left(a_i\right)}{\Σ}{x}_k}{\Σ}}\underset{\stackrel{\→}{y}:\underset{a_k\∈N\left(a_i\right)}{\Σ}{x}_k{y}_k=t}{\Σ}\underset{a_j\∈N\left(a_i\right)}{\Π}\left(p{\left(a_j\right)}^{y_j}\·{\left(1-p\left(a_j\right)\right)}^{1-y_j}\right)\≥P---\left(5\right);$

$x_j\∈\{0,1\},\∀a_j\∈N\left(a_i\right)---\left(6\right).$

Above-mentioned constraints (5) ensures a _ithe probability of meeting at least m-1 other users is at least P, satisfy condition 2 requirement; for length is | N (a _i) | vector.

3rd step, server pass through after receiving enciphered data sheet to build the reconstruct of data slice table realization to initial data, and concrete steps comprise:

3.1) according to the enciphered data sheet received, adopt the private key of user in asymmetric decryption technology and the corresponding first step, enciphered data sheet is decrypted, obtain identification information and coded data sheet;

3.2) identification information and coded data sheet are added in data slice table, and judge when the coded data sheet belonging to same initial data at least reaches k sheet, the correcting and eleting codes decoding technique corresponding with the first step is then adopted to reconstruct this initial data < t, l, d >;

3.3) the coded data sheet belonging to this initial data is deleted from data slice table, and preserve the primary data information (pdi) < t that reconstructs out, l, d >, until complete the deciphering of all enciphered message sheets, obtain all raw sensed data.

The present invention relates to a kind of system realizing said method, comprise: perception data burst coding module, data slice Switching Module and data partial decode reconstructed module, wherein: perception data burst coding module is connected with data slice Switching Module and transfer encoding encrypted data sheet information, data slice Switching Module is connected with data partial decode reconstructed module and transfer encoding encrypted data sheet information.

Described perception data burst coding module comprises: correcting and eleting codes coding unit, identification information generation unit, asymmetric encryption unit, wherein correcting and eleting codes coding unit carries out cutting coding to initial data, identification information generation unit is according to the unique identification of user profile generation for data abundance, asymmetric encryption unit is encrypted coded data sheet and identification information, prevents listening in information.

Described data slice Switching Module comprises: data slice crosspoint, and this unit is responsible for the forwarding object set determining data slice, and the data slice after coding encrypting is transmitted to this collection object.

Described data partial decode reconstructed module comprises: asymmetric decryption unit, correcting and eleting codes decoding and reconstituting unit, wherein asymmetric decryption unit is corresponding with asymmetric encryption unit above, be responsible for the deciphering of enciphered data, correcting and eleting codes decoding and reconstituting unit is corresponding with correcting and eleting codes coding unit above, is responsible for the decoding restructuring of coded data sheet.

Technique effect

The present invention compared with prior art, its advantage comprises: the privacy information effectively can protecting user in participatory sensory perceptual system, take precautions against and steal attack from the privacy of service provider and surrounding participant, be first mechanism of the privacy information protection for multimedia aware data simultaneously; Secondly, the method can improve Fault Tolerance greatly, ensures the robustness that system is higher to reduce system communication expense and computing cost simultaneously.

Accompanying drawing explanation

Fig. 1 is for the present invention is based on data fragmentation Privacy Preservation Mechanism general frame figure.

Fig. 2 is each functional module and unit relation schematic diagram in the present invention.

Fig. 3 is TMU data slice exchanging policy schematic diagram in embodiment.

Embodiment

Elaborate to embodiments of the invention below, the present embodiment is implemented under premised on technical solution of the present invention, give detailed execution mode and concrete operating process, but protection scope of the present invention is not limited to following embodiment.

Embodiment 1

As shown in Figure 1, the present embodiment comprises the following steps:

The first step, data fragmentation are encoded

1.1) according to user a _ithe perception data < t of ∈ N, l, d > and encoding rate (k/m), adopt erasure code method that perception data is divided into k sheet, and then coding produces m sheet perception data block { r _ij| 1≤j≤m}, wherein: a _ifor being numbered the user of i, N is the set of all users, < t, l, d > represent a time be t, position is l, content is the perception data of d, k refers to: initial data is cut into k sheet by correcting and eleting codes technology; M refers to: the data slice number that k sheet data produce after correcting and eleting codes coding, and k≤m; K/m presentation code rate; r _ijrepresent user a _ijth slice encode after data slice;

Correcting and eleting codes adopts RS code or Tornado code to realize in the present embodiment;

1.2) adopt cryptographic hashing algorithm to each user a _igenerate unique corresponding identification information tag, i.e. tag ← H (i, nonce), wherein: H () is Hash encryption function, and i is user a _inumbering, nonce is the random number between [0,1];

1.3) the perception data sheet { r adopting rivest, shamir, adelman to obtain step 1.1 _ij| 1≤j≤m} and encrypting user mark tag is encrypted, and generates the enciphered data sheet for transmitting, i.e. r ' _ij=ENCRYPT (r _ij|| tag, KEY _pub), wherein ENCRYPT () is asymmetric encryption function, || be character string attended operation, KEY _pubfor encrypted public key, r ' _ijfor data slice r _ijdata slice after corresponding encryption.

Second step: data slice exchanges transmission: in order to prevent the identity information of service provider's Direct Recognition data owner, thus leakage user privacy information, the enciphered data sheet that the first step generates is retained a slice and remainder data sheet and surrounding user exchanged, and transmits all data slice to server after exchange.

In the present embodiment, propose two kinds of data slice exchanging policies, namely meet exchange (TMU, TransferonMeetUp) and minimum cost exchange (MCT, MinimalCostTransfer).

Described exchange of meeting refers to: its enciphered data sheet is sent to other users run in moving process by the owner successively, until enciphered data sheet life cycle terminates, then periodically sends to server by the user receiving enciphered data sheet.

As shown in Figure 3, illustrate the basic thought of TMU exchanges data strategy visually: establish (on Fig. 3) user A to march to office from residence, the equipment of user A stores the data to be transmitted sheet of three encryptions at present, and A meets in T1, T2, T3 moment with B, C, D successively in advance process; Then according to TMU exchanging policy (under Fig. 3), T1 moment A sends to B data slice A1, and because B can supply to exchange without data slice, therefore after the T1 moment, A remains 2, and B obtains the enciphered data sheet of 1 A, the like.

Exchange problem although TMU strategy can well solve data slice, TMU is still a kind of exchangeable object selection strategy relatively blindly.In actual environment, there is larger difference (such as energy consumption, bandwidth, transmission time, transmission cost etc.) in different mobile device self, therefore different mobile devices is when exchanging same data slice, may cause different overheads (being referred to as cost).In this case, TMU exchanging policy can cause great system cost to waste, have employed minimum cost thus in the present embodiment to exchange, described minimum cost exchanges and refers to: while choosing data slice exchangeable object, overhead little as far as possible can be ensured, namely be located in data slice life cycle, user a _i∈ N can be with | N (a _i) | individual user meets; For each user a _j∈ N (a _i) all there are two attribute p (a _j) and c (a _j), wherein p (a _j) represent a _jwith a _ithe probability met, c (a _j) represent a _jwith a _iexchange the overhead born required for a slice data, p (a in the present invention _j) and c (a _j) obtain by historical data and existing mobility prediction model (Mobilitypredictionmodel).

Thus, the target of MCT strategy can be expressed as: for each user a _j∈ N (a _i), ensureing, under overhead prerequisite little as far as possible, to choose a subset as the relay transmission node of its enciphered data sheet, and meet one of condition below:

Condition 1: require at least to run into m-1 user; The problem meeting this condition is referred to as MCT-EXP problem;

Condition 2: require that the probability running into m-1 user is at least P (0<=P<=1), the problem meeting this condition is referred to as MCT-PRO problem;

For above two problems, corresponding solution is proposed below:

MCT-EXP issue-resolution

MCT-EXP problem form can turn to Zero-one integer programming problem, and modeling is as follows:

Objective： $min\underset{a_j\&Element;N\left(a_i\right)}{\&Sigma;}c\left(a_j\right)p\left(a_j\right)x_j$

Subjectto： $\underset{a_j\&Element;N\left(a_i\right)}{\&Sigma;}p\left(a_j\right)x_j\&GreaterEqual;m-1,---\left(1\right);$

$x_j\&Element;\{0,1\},\&ForAll;a_j\&Element;N\left(a_i\right)---\left(2\right).$

Above-mentioned constraints (1) ensure that user a _i∈ N at least runs into m-1 other users, and constraints (2) represents x _jspan, x _j=1 represents a _jbe chosen as exchangeable object, otherwise then represent not selected.

Because above-mentioned MCT-EXP problem is very similar to traditional backpacks problem, thus can reduction to 0-1 knapsack problem, reduction result is as follows:

Objective： $\max \underset{a_j\&Element;N\left(a_i\right)}{\&Sigma;}c\left(a_j\right)p\left(a_j\right)\left(1-x_j\right);$

Subjectto： $\underset{a_j\&Element;N\left(a_i\right)}{\&Sigma;}p\left(a_j\right)\left(1-x_j\right)\&le;\underset{a_j\&Element;N\left(a_i\right)}{\&Sigma;}p\left(a_j\right)-\left(m-1\right),---\left(3\right);$

$x_j\&Element;\{0,1\},\&ForAll;a_j\&Element;N\left(a_i\right)---\left(4\right).$

So far, MCT-EXP problem is converted into 0-1 knapsack problem completely, because this problem has ripe FullyPolynomialTimeApproximationScheme (FPTAS) algorithm, good approximate solution can be tried to achieve in polynomial time, so place no longer describes in detail.

MCT-PRO issue-resolution: although MCT-EXP problem can find FPTAS algorithm to deal with problems, the existing defects of MCT-EXP problem own, because it can not ensure user ai and other at least probability of meeting of m-1 user, namely can not satisfy condition 2.Therefore, propose the optimisation strategy for MCT-PRO problem, the probability making user ai meet other m-1 user is at least P.

MCT-PRO problem can formalization representation as follows:

Objective： $\min \frac{\underset{\stackrel{\&RightArrow;}{y}:\underset{a_k\&Element;N\left(a_i\right)}{\&Sigma;}{x}_k{y}_k=m-1}{\&Sigma;}\left(\underset{a_j\&Element;N\left(a_i\right)}{\&Sigma;}\right(c\left(a_j\right)x_j{y}_j\left)\underset{a_j\&Element;N\left(a_i\right)}{\&Pi;}p{\left(a_j\right)}^{y_j}\right)}{\underset{\stackrel{\&RightArrow;}{y}:\underset{a_k\&Element;N\left(a_i\right)}{\&Sigma;}{x}_k{y}_k=m-1}{\&Sigma;}\underset{a_j\&Element;N\left(a_i\right)}{\&Pi;}p{\left(a_j\right)}^{y_j}};$

Subjectto： $\underset{t=m-1}{\overset{\underset{a_k\&Element;N\left(a_i\right)}{\&Sigma;}{x}_k}{\&Sigma;}}\underset{\stackrel{\&RightArrow;}{y}:\underset{a_k\&Element;N\left(a_i\right)}{\&Sigma;}{x}_k{y}_k=t}{\&Sigma;}\underset{a_j\&Element;N\left(a_i\right)}{\&Pi;}\left(p{\left(a_j\right)}^{y_j}\&CenterDot;{\left(1-p\left(a_j\right)\right)}^{1-y_j}\right)\&GreaterEqual;P---\left(5\right);$

$x_j\&Element;\{0,1\},\&ForAll;a_j\&Element;N\left(a_i\right)---\left(6\right).$

Above-mentioned constraints (5) ensures that the probability that ai meets at least m-1 other users is at least P, meets the requirement of constraints (2); for length is | N (a _i) | vector, constraints (6) and constraints (2), (4) are identical.

By analysis, the problems referred to above are np hard problem, the optimal solution cannot asked in polynomial time, propose a kind of multinomial greedy algorithm thus and solve MCT-PRO problem, this algorithm is divided into two steps to complete, step one is called the critical user of discovery, and step 2 is called determines goal set, specifically can be described below:

First, Rule of judgment | N (a _i) | whether < m-1 sets up, if set up, then illustrates that set element number is less than m-1, cannot satisfy condition 2 requirement, program stopped, algorithm without solution, wherein | N (a _i) | express possibility and user a _iuser's number of meeting;

Otherwise, for set N (a _i) element is according to p (a _j)/c (a _j) descending sort obtains sequence dynamic programming algorithm is adopted to β sequence, finds out front α the element for the first time constraints (5) being met in β sequence; Because α element front in β sequence meets (5), analyze known, front γ (γ>=α) individual element also necessarily meets constraints (5), and note α is critical number, a ' _αbe designated as critical user.

Above-mentioned critical user finds that algorithm can determine critical user a ' _α, then for comprise arbitrarily γ ∈ before β sequence α, α+1 ..., | N (a _i) | the set of individual element, all can be used as the feasible solution of MCT-PRO problem.Here is the goal set determination algorithm proposed based on critical value α, and be used for determining the scale of goal set, i.e. the value of γ, makes the target function of MCT-PRO problem minimum.

For determining goal set scale, user is gathered N (a _i), set element collision probability and overhead and sequence with critical user a ' _αas algorithm input, adopt the thought of Dynamic Programming, find out the γ (γ>=α) making MCT-PRO problem target function value minimum, and front γ the element getting sequence β adds goal set F.This algorithm is a kind of polynomial time greedy algorithm, can be determined the data slice exchangeable object set making overhead minimum by this algorithm.

3rd step: data slice decoding and reconstituting: initial data, after point slice encode and exchange transmit stage, finally converges to service provider's (server).For every bar initial data, server receives and at least just successfully can reconstruct initial data after k sheet data.Safeguard a tables of data (CachetableT) for all data slice received at memory headroom in this step, as the input of restructing algorithm, concrete steps comprise:

3.1) according to the enciphered data sheet received, adopt the private key of user in asymmetric decryption function and the corresponding first step, enciphered data sheet is decrypted, obtain identification information and coded data sheet;

3.2) identification information and coded data sheet are added in data slice table, and judge when the coded data sheet belonging to same initial data at least reaches k sheet, the correcting and eleting codes decoding technique corresponding with the first step is then adopted to reconstruct this initial data < t, l, d >;

3.3) the coded data sheet belonging to this initial data is deleted from data slice table, and preserve the primary data information (pdi) < t that reconstructs out, l, d >, until complete the deciphering of all enciphered message sheets, obtain all raw sensed data.

Compared with prior art; the progress of the technical performance that the present embodiment has and the lifting of experimental data index show: first; the privacy information of what the present embodiment was fabulous protect participatory sensory perceptual system participant; reach the protected effect of k-anonymity, secondly, what the present embodiment can be good operates on mobile terminal device; enhance the fault-tolerant ability of participatory sensory perceptual system greatly; meanwhile, by design and the optimization of algorithm, the overhead of mobile device is effectively reduced.

Claims (7)

1., based on a participatory sensory perceptual system method for secret protection for data fragmentation, it is characterized in that, comprise the following steps:

The first step, obtain raw sensed data by mobile device, correcting and eleting codes is adopted to carry out a point slice encode to initial data, then the mobile device user mark after hash function encryption and the data slice after point slice encode being carried out asymmetric data encryption, producing the enciphered data sheet for transmitting;

Second step, the enciphered data sheet that the first step generates retained a slice and remainder data sheet and surrounding user exchanged, and transmitting all enciphered data sheets to server after exchange;

3rd step, server pass through after receiving enciphered data sheet to build the reconstruct of data slice table realization to initial data;

Described exchange comprises: meet exchange and minimum cost exchange, wherein:

Described exchange of meeting refers to: its enciphered data sheet is sent to other users run in moving process by the owner successively, until enciphered data sheet life cycle terminates, then periodically sends to server by the user receiving enciphered data sheet;

Described minimum cost exchanges and refers to: under the prerequisite ensureing overhead little as far as possible, choose enciphered data sheet exchangeable object, be namely located in enciphered data sheet life cycle, user a _i∈ N can be with | N (a _i) | individual user meets, for each user a that will meet _j∈ N (a _i), p (a _j) represent a _jwith a _icollision probability, c (a _j) represent a _jwith a _iexchange the overhead born required for a slice data.

2. method according to claim 1, is characterized in that, described collision probability p (a _j) and overhead c (a _j) obtained by historical data and mobility prediction model;

Described mobility prediction model refers to: for each user a _j∈ N (a _i), ensureing, under overhead prerequisite little as far as possible, to choose a subset as the relay transmission node of its enciphered data sheet, and meet any one condition below:

Condition 1: require at least to run into m-1 user, namely meet:

Objective： $min\underset{a_j\&Element;N\left(a_i\right)}{\&Sigma;}c\left(a_j\right)p\left(a_j\right)x_j$

Subjectto： $\underset{a_j\&Element;N\left(a_i\right)}{\&Sigma;}p\left(a_j\right)x_j\&GreaterEqual;m-1,---\left(1\right);$

$x_j\&Element;\{0,1\},\&ForAll;a_j\&Element;N\left(a_i\right)---\left(2\right);$

Above-mentioned formula (1) ensure that user a _i∈ N at least runs into m-1 other users, and formula (2) represents x _jspan, x _j=1 represents a _jbe chosen as exchangeable object, otherwise then represent not selected;

Condition 2: require that the probability running at least m-1 user is at least P, 0≤P≤1, namely meet:

Objective： $min\frac{\underset{\stackrel{\&RightArrow;}{y}:\underset{a_k\&Element;N\left(a_i\right)}{\&Sigma;}{x}_k{y}_k=m-1}{\&Sigma;}\left(\underset{a_j\&Element;N\left(a_i\right)}{\&Sigma;}\right(c\left(a_j\right)x_j{y}_j)\underset{a_j\&Element;N\left(a_i\right)}{\&Pi;}p{\left(a_j\right)}^{y_j})}{\underset{\stackrel{\&RightArrow;}{y}:\underset{a_k\&Element;N\left(a_i\right)}{\&Sigma;}{x}_k{y}_k=m-1}{\&Sigma;}\underset{a_j\&Element;N\left(a_i\right)}{\&Pi;}p{\left(a_j\right)}^{y_j}};$

Subjectto： $\underset{t=m-1}{\overset{\underset{a_k\&Element;N\left(a_i\right)}{\&Sigma;}{x}_k}{\&Sigma;}}\underset{\stackrel{\&RightArrow;}{y}:\underset{a_k\&Element;N\left(a_i\right)}{\&Sigma;}{x}_k{y}_k=t}{\&Sigma;}\underset{a_j\&Element;N\left(a_i\right)}{\&Pi;}\left(p{\left(a_j\right)}^{y_j}\&CenterDot;{\left(1-p\left(a_j\right)\right)}^{1-y_j}\right)\&GreaterEqual;P---\left(5\right);$

$x_j\&Element;\{0,1\},\&ForAll;a_j\&Element;N\left(a_i\right)---\left(6\right);$

Above-mentioned formula (5) ensures a _ithe probability of meeting at least m-1 other users is at least P, satisfy condition 2 requirement; for length is | N (a _i) | vector.

3. method according to claim 1, is characterized in that, the 3rd described step concrete steps comprise:

3.1) according to the enciphered data sheet received, adopt the private key of user in asymmetric decryption technology and the corresponding first step, enciphered data sheet is decrypted, obtain identification information and coded data sheet;

3.2) identification information and coded data sheet are added in data slice table, and judge when the coded data sheet belonging to same initial data at least reaches k sheet, the correcting and eleting codes decoding technique corresponding with the first step is then adopted to reconstruct this initial data <t, l, d>;

3.3) the coded data sheet belonging to this initial data is deleted from data slice table, and preserve the primary data information (pdi) <t that reconstructs out, l, d>, until complete the deciphering of all enciphered message sheets, obtain all raw sensed data.

4. one kind realizes the system of method described in above-mentioned arbitrary claim, it is characterized in that, comprise: perception data burst coding module, data slice Switching Module and data partial decode reconstructed module, wherein: perception data burst coding module is connected with data slice Switching Module and transfer encoding encrypted data sheet information, data slice Switching Module is connected with data partial decode reconstructed module and transfer encoding encrypted data sheet information.

5. system according to claim 4, it is characterized in that, described perception data burst coding module comprises: correcting and eleting codes coding unit, identification information generation unit, asymmetric encryption unit, wherein correcting and eleting codes coding unit carries out cutting coding to initial data, identification information generation unit is according to the unique identification of user profile generation for data abundance, asymmetric encryption unit is encrypted coded data sheet and identification information, prevents listening in information.

6. system according to claim 4, is characterized in that, described data slice Switching Module comprises: data slice crosspoint, and this unit is responsible for the forwarding object set determining data slice, and the data slice after coding encrypting is transmitted to this collection object.

7. system according to claim 4, it is characterized in that, described data partial decode reconstructed module comprises: asymmetric decryption unit, correcting and eleting codes decoding and reconstituting unit, wherein asymmetric decryption unit is corresponding with asymmetric encryption unit above, be responsible for the deciphering of enciphered data, correcting and eleting codes decoding and reconstituting unit is corresponding with correcting and eleting codes coding unit above, is responsible for the decoding restructuring of coded data sheet.