CN110336657A - A kind of light OFDM dynamic key production method based on the characteristic of channel - Google Patents
A kind of light OFDM dynamic key production method based on the characteristic of channel Download PDFInfo
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- CN110336657A CN110336657A CN201910592164.0A CN201910592164A CN110336657A CN 110336657 A CN110336657 A CN 110336657A CN 201910592164 A CN201910592164 A CN 201910592164A CN 110336657 A CN110336657 A CN 110336657A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/70—Photonic quantum communication
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
- H04L9/001—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols using chaotic signals
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
- H04L9/08—Key distribution or management, e.g. generation, sharing or updating, of cryptographic keys or passwords
- H04L9/0861—Generation of secret information including derivation or calculation of cryptographic keys or passwords
- H04L9/0869—Generation of secret information including derivation or calculation of cryptographic keys or passwords involving random numbers or seeds
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
- H04L9/08—Key distribution or management, e.g. generation, sharing or updating, of cryptographic keys or passwords
- H04L9/0891—Revocation or update of secret information, e.g. encryption key update or rekeying
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Abstract
The invention discloses the light OFDM dynamic key production methods based on the characteristic of channel.The step of this method is realized are as follows: (1) communicating pair generates one section of random probing signal respectively, while being sent to other side；(2) communicating pair respectively estimates the characteristic of channel after receiving the detectable signal in step 1；(3) phase value that communicating pair respectively asks for obtained each sub-carrier channels characteristic in step 2 is quantified and generates one section of binary sequence；(4) communicating pair by random probing signal and step 3 that the above-mentioned random probing signal locally generated and other side send over it is each it is de-quantization after phase binary sequence successively carry out exclusive or and obtain final required dynamic key.This method is effectively utilized the characteristic of channel of communicating pair and local privately owned Random Binary Signals dynamically change key, and effectively improve the randomness of key, obtained key can carry out encryption in physical layer relevant operation, strong applicability, and secrecy ability protrudes.
Description
Technical field
The present invention provides a kind of light OFDM dynamic key production method based on the characteristic of channel, is light OFDM encryption in physical layer
Provide dynamic key production scheme.
Background technique
With the development of the high-speed data services such as IPTV, high definition television, large-scale interactive network game, the bandwidth for accessing net is needed
Asking will sharply increase.In recent years, orthogonal frequency division multiplexing (OFDM) modulation with its resisting chromatic dispersion ability is strong, the availability of frequency spectrum is high the advantages that
It is introduced into fiber optic communication.Meanwhile it can easily be handled by Digital Signal Processing (DSP).In addition, Direct-detection Optical
Ofdm system (DD-OOFDM) is with structure is simple, Dynamic Bandwidth Allocation is flexible, Heterogeneous service is transparent, compatible with existing network
The advantages that good and show great potential in next-generation optical access network.Since the physical layer of optical access network is easy to be attacked by various
It hits, with sharply increasing for user and network capacity, safety of physical layer problem is become more and more important.Previous method, which uses, to be added
Close agreement encrypts data frame, safety problem is placed on to the higher level of network, therefore in unsafe physical layer
Upper building safety approach is risky.
Investigation discovery to existing literature, light OFDM encryption in physical layer scheme at this stage mostly use chaos sequence pair
OFDM symbol block carries out the scramble in frequency domain and time domain.[Zhang L, Xin X, Liu B, the et al.Physical- of document 1
enhanced secure strategy in an OFDM-PON[J].Optics Express,2012,20(3):2255-
2265] it proposes and generates n rank Scrambling Matrix P using One-dimensional Logic chaotic maps to encrypt frequency domain ofdm signal, due to listener-in
The initial value of chaos sequence, the step-length of logical mappings and iteration are not known, so being substantially difficult to restore original signal.Document 2
[Sultan A,Yang X,Hajomer A A E,et al.Dynamic QAM Mapping for Physical-Layer
Security Using Digital Chaos [J] .IEEE Access, 2018,6:47199-47205] propose four-dimensional logic
Mapping scheme, by each subcarrier symbol amplitude and phase carried out scramble, so that it is randomly dispersed in a round star
In seat figure, key space is huge, and cipher round results are significant.It is existing although more for light OFDM encryption in physical layer research achievement
The encipherment scheme in stage is all that communicating pair is needed to exchange key initial value in advance, and once it is determined that initial value just no longer changes later,
Entirely key is all static, and this reduces the security performances of system.
Summary of the invention
The present invention is in view of the deficienciess of the prior art, provide a kind of light OFDM dynamic key production based on the characteristic of channel
Method, key change in real time with the characteristic of channel and random probing signal, effectively promote the safety of optical OFDM system.
In order to achieve the above objectives, the present invention is achieved by the following technical solutions:
A kind of light OFDM dynamic key production method based on the characteristic of channel, wherein key generated is local random letter
Number, the exclusive or of channel phase after the detectable signal that receives and quantization is as a result, comprise the following steps that
Step 1: transmitting terminal A generates random binary sequence XtAnd it is sent to receiving end B；In coherence time, B generate with
Machine binary sequence XrIt is sent to A；
Step 2: transmitting terminal A estimation carries signal XrN number of subcarrier the characteristic of channel, obtain the channel of communicating pair
Response:WhereinIt indicates i-th of transmitting terminal A
The channel response of subcarrier；B estimation in receiving end carries signal XtN number of subcarrier the characteristic of channel, obtain the letter of communicating pair
Road response:WhereinIndicate receiving end B i-th
The channel response of a subcarrier；
Step 3: transmitting terminal A is allQuantified to obtain binary phase sequence Pa；Similarly, receiving end B is by institute
HaveBinary phase sequence P is obtained after quantizationb；
Step 4: the phase quantization sequence P that transmitting terminal A will be obtainedaWith random binary sequence XrAnd two locally generated
System sequence XtIt carries out XOR operation and generates key Ka；Similarly, the phase quantization sequence P that receiving end B will be obtainedbWith random two into
Sequence X processedtAnd the binary sequence X locally generatedrIt carries out XOR operation and generates key Kb。
Random binary sequence is loaded into the data subcarrier of an OFDM with certain modulation system in the step 1
Upper to be used as random probing signal, wherein random sequence length is consistent with key digit.
Be in the step 3 by phase interval (0,2 π] be divided into Q subinterval,OrFall on corresponding subinterval
It is interior and carry out corresponding binary coding, transmitting terminal A is allA binary system phase is merged into after the completion of coding in order
Bit sequence Pa；Receiving end B is allA binary phase sequence P is merged into after the completion of coding in orderb.Assuming that being wanted
The key length of generation is M, and the phase number for needing to quantify is N, then Q meets formula:WhereinExpression takes upwards
It is whole；P after quantizationaAnd PbM value before interception.
The invention has the following advantages over the prior art:
Light OFDM dynamic key production method proposed by the present invention based on the characteristic of channel, key generated is no longer quiet
State key does not need communicating pair and appoints key initial value, effectively raises the ability of safety of physical layer communication.The present invention mentions
Dynamic key out can automatic not timing be updated, the key of generation combines other encryption technologies, so that listener-in is just
Really decryption Content of Communication difficulty further increases, and security performance is further promoted compared with the prior art.Present invention dynamic generated
Only the characteristic of channel between communicating pair and random signal are related for key, and communicating pair generates final close under the technical program
Key is consistent, and the key of acquisition can be calculated for the initial value and parameter of more new accountant rule and as other data encryptions
The key of method.The present invention is suitable for optical OFDM system, is also applied for the dynamic key production of other optic communication encryption systems.
Detailed description of the invention
Fig. 1 is light OFDM dynamic key production process schematic of the present invention.
Specific embodiment
Elaborate below in conjunction with attached drawing to the embodiment of the present invention: the present embodiment is before technical solution of the present invention is
It puts and is implemented, give detailed embodiment and operating process, but protection scope of the present invention is not limited to following realities
Apply example.
The present embodiment is carried out in optical OFDM system, and communicating pair 128 key sequences of each self-generating, modulation format is adopted
With 16QAM mode, subcarrier number 64, valid data subcarrier number is 28, entire dynamic key production process such as Fig. 1 institute
Show, detailed process is as follows:
Step 1: transmitting terminal A generates random binary sequence XtAnd it is sent to receiving end B.In coherence time, B generate with
Machine binary sequence XrIt is sent to A.
Binary sequence X described in step 1t、XrIt is the random binary sequence with required key length consistent 128
Column go wrong during the decoding of receiving end in order to prevent, and 128 above-mentioned random binary sequences can use some error correction
Coding techniques carries out verification and error correction, simplest such as even-odd check.Xt、XrAdd respectively after serioparallel exchange and 16QAM modulation
It is downloaded on respective subcarrier.
Step 2: transmitting terminal A estimation carries signal XrN number of subcarrier the characteristic of channel, obtain the channel of communicating pair
ResponseWhereinIt indicates i-th of transmitting terminal
The channel response of subcarrier)；B estimation in receiving end carries signal XtN number of subcarrier the characteristic of channel, obtain the letter of communicating pair
Road responseWhereinIndicate receiving end i-th
The channel response of a subcarrier).
Step 3: transmitting terminal A is allQuantified to obtain binary phase sequence Pa；Similarly, receiving end B is by institute
HaveBinary phase sequence P is obtained after quantizationb.Wherein, by phase interval (0,2 π] be divided into Q subinterval,It falls
In to corresponding subinterval and corresponding binary coding is carried out, transmitting terminal A (receiving end B) is allCoding is completed
Merge into a binary phase sequence P in order afterwardsa(Pb)。
The Q meets formula:Wherein M is entire key length (M=128), and N is the phase for needing to quantify
Number (due to modulating using 16QAM, it is known that the valid data subcarrier number N=32 of needs), Q value, which is calculated, is
16, i.e., will (0,2 π] be divided into 16 subintervals ((0, π/8], (and π/8, π/4] ..., the corresponding each section (15 π/8,2 π])
Phase quantization binary sequence is (0000,0001 .., 1111).
Step 4: the phase quantization sequence P that transmitting terminal A will be obtainedaWith random binary sequence XrAnd two locally generated
System sequence XtIt carries out XOR operation and generates key Ka.Similarly, the phase quantization sequence P that receiving end B will be obtainedbWith random two into
Sequence X processedtAnd the binary sequence X locally generatedrIt carries out XOR operation and generates key Kb。
The key sequence of obtained legitimate correspondence both sides is consistent, and the key obtained not only with the letter of communicating pair
Road characteristic is related, and related with the random binary sequence of generation.The dynamic key characteristics exhibit of this method is in channel spy
Property can change with the change of time, and the random sequence for detectable signal is also dynamically generated.
Legitimate secret generated is only related with the channel at transmitting-receiving both ends and random signal, and listener-in cannot obtain and close
It the same communication channel of method communicating pair and transmitting-receiving end equipment cannot be attacked obtains the random binary sequence of legal sending and receiving end,
So attacker, which can hardly obtain, correctly generates key, and legitimate secret can be with the change of not timing, the encipherment scheme
It is very safe and efficient.Legitimate secret K generatedaAnd KbCan be used to more new accountant rule initial value and parameter and
Key as other data encryption algorithm.
Claims (4)
1. a kind of light OFDM dynamic key production method based on the characteristic of channel, wherein key generated is local random letter
Number, send end signal and quantization after channel phase exclusive or as a result, it is characterised in that it includes steps are as follows:
Step 1: transmitting terminal A generates random binary sequence XtAnd it is sent to receiving end B；In coherence time, B generate random two into
Sequence X processedrIt is sent to A；
Step 2: transmitting terminal A estimation carries signal XrN number of subcarrier the characteristic of channel, obtain the channel response of communicating pair:WhereinIndicate that i-th of son of transmitting terminal A carries
The channel response of wave；B estimation in receiving end carries signal XtN number of subcarrier the characteristic of channel, obtain communicating pair channel ring
It answers:WhereinIndicate i-th of son of receiving end B
The channel response of carrier wave；
Step 3: transmitting terminal A is allQuantified to obtain binary phase sequence Pa；Similarly, receiving end B will be allBinary phase sequence P is obtained after quantizationb；
Step 4: the phase quantization sequence P that transmitting terminal A will be obtainedaWith random binary sequence XrAnd the binary system locally generated
Sequence XtIt carries out XOR operation and generates key Ka；Similarly, the phase quantization sequence P that receiving end B will be obtainedbWith random binary sequence
Arrange XtAnd the binary sequence X locally generatedrIt carries out XOR operation and generates key Kb。
2. the light OFDM dynamic key production method according to claim 1 based on the characteristic of channel, it is characterised in that: described
Random binary sequence is loaded on the data subcarrier of an OFDM as random using certain modulation system and is visited in step 1
Signal is surveyed, wherein random sequence length is consistent with key digit.
3. the light OFDM dynamic key production method according to claim 1 based on the characteristic of channel, it is characterised in that: described
Be in step 3 by phase interval (0,2 π] be divided into Q subinterval,OrIt falls in corresponding subinterval and is corresponded to
Binary coding, transmitting terminal A is allA binary phase sequence P is merged into after the completion of coding in ordera；It will connect
Receiving end B is allA binary phase sequence P is merged into after the completion of coding in orderb。
4. the light OFDM dynamic key production method according to claim 1 or 3 based on the characteristic of channel, it is characterised in that:
Assume that the key length to be generated is M in the step 3, the phase number for needing to quantify is N, then Q meets formula:WhereinExpression rounds up；P after quantizationaAnd PbM value before interception.
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Cited By (4)
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| CN111148099A (en) * | 2020-01-02 | 2020-05-12 | 燕山大学 | Side channel key generation method, device and communication system |
| CN112533199A (en) * | 2020-11-25 | 2021-03-19 | 南京熊猫电子股份有限公司 | OFDM channel physical key generation method and device based on USRP and computer equipment |
| CN113179513A (en) * | 2021-04-16 | 2021-07-27 | 中国人民解放军国防科技大学 | Wireless channel key generation method and device based on intelligent reflector phase assistance |
| CN113271201A (en) * | 2021-05-27 | 2021-08-17 | 国网江苏省电力有限公司南京供电分公司 | Dynamic AES physical layer data encryption method |
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| CN112533199A (en) * | 2020-11-25 | 2021-03-19 | 南京熊猫电子股份有限公司 | OFDM channel physical key generation method and device based on USRP and computer equipment |
| CN113179513A (en) * | 2021-04-16 | 2021-07-27 | 中国人民解放军国防科技大学 | Wireless channel key generation method and device based on intelligent reflector phase assistance |
| CN113179513B (en) * | 2021-04-16 | 2022-08-09 | 中国人民解放军国防科技大学 | Wireless channel key generation method and device based on intelligent reflector phase assistance |
| CN113271201A (en) * | 2021-05-27 | 2021-08-17 | 国网江苏省电力有限公司南京供电分公司 | Dynamic AES physical layer data encryption method |
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