15 Vol 5 No 6

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8/2/2019 15 Vol 5 No 6

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\red0\green0\blue0;\red0\green0\blue0;\red0\green0\blue0;\red0\green0\blue0;\red0\green0\blue0;\red0\green0\blue0;\red0\green0\blue0;\red0\green0\blue0;}\viewkind1\viewscale100\paperw12240\paperh15840\par\pard\par\pard\ql\ul0\nosupersub\cf1\f2\fs18JournalofTheoreticalandAppliedInformationTechnology\par\pard\par\pard\ql\ul0\nosupersub\cf2\f3\fs18©2005-2009JATIT.Allrightsreserved.\par\pard\par\pard\ql\ul0\nosupersub\cf4\f5\fs18www.jatit.org\par\pard\par\pard\qc\ul0\nosupersub\cf7\f8\fs32EFFICIENTMETHODOFAUDIOSTEGANOGRAPHY

BYMODIFIEDLSBALGORITHMANDSTRONGENCRYPTIONKEYWITHENHANCEDSECURITY\par\pard\par\pard\qc\ul0\nosupersub\cf8\f9\fs181\ul0\nosupersub\cf10\f11\fs20RSRIDEVI,\ul0\nosupersub\cf8\f9\fs182\ul0\nosupersub\cf10\f11\fs20DR.ADAMODARAM,\ul0\nosupersub\cf8\f9\fs183\ul0\nosupersub\cf10\f11\fs20DR.SVL.NARASIMHAM\ul0\nosupersub\cf9\f10\fs181\ul0\nosupersub\cf6\f7\fs20Assoc.Prof.,DepartmentofComputerScienceandEngineering,JNTUCEH,Hyderabad\ul0\nosupersub\cf9\f10\fs182\ul0\nosupersub\cf6\f7\fs20Prof.,DepartmentofComputerScienceandEngineering,JNTUCEH,Hyderabad\ul0\nosupersub\cf9\f10\fs183\ul0\nosupersub\cf6\f7\fs20Prof.,SchoolofInformationTechnology,JNTUH,Hyderabad\par\pard\par\pard\qlE-mail:\ul0\nosupersub\cf11\f12\fs20sridevirangu@yahoo.com\ul0\

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nosupersub\cf6\f7\fs20,\ul0\nosupersub\cf11\f12\fs20damadorama@gmail.com\ul0\nosupersub\cf6\f7\fs20,\ul0\nosupersub\cf12\f13\fs18\ul0\nosupersub\cf13\f14\fs18svlnarasimham@jntuh.ac.in\par\pard\par\pard\ql\ul0\nosupersub\cf10\f11\fs20ABSTRACT\par\pard\par\pard\qj \ul0\nosupersub\cf6\f7\fs20Inthecurrentinternetcommunity,securedatatransferislimitedduetoitsattackmadeondatacommunication.Somorerobustmethodsarechosensothattheyensuresecureddatatransfer.OneofthesolutionswhichcametotherescueistheaudioSteganography.Butexistingaudiosteganographicsystemshavepoorinterface,verylowlevelimplementation,difficulttounderstandandvalidonlyforcertainaudioformatswithrestrictedmessagesize.\par\pard\par\pard EnhancedAudioSteganography(EAS)isoneproposedsystemwhichisbasedonaudioSteganographyandcryptography,ensuressecuredatatransferbetweenthesourceanddestination.EAS\par usesmostpowerfulencryptionalgorithminthefirstlevelofsecurity,whichisverycomplextobreak.InthesecondlevelitusesamorepowerfulmodifiedLSB(LeastSignificantBit)Algorithmtoencodethemessageintoaudio.Itperformsbitlevelmanipulationtoencodethemessage.\par\pard\par\pard\qj Thebasicideabehindthispaperistoprovideagood,efficientmethodforhidingthedatafromhackersandsenttothedestinationinasafermanner.Thoughitiswellmodulatedsoftwareithasbeenlimitedtocertainrestrictions.Thequalityofsounddependsonthesizeoftheaudiowhichtheuserselectsandlengthofthemessage.Thoughitshowsbitleveldeviationsinthefrequencychart,asawholethechangeintheaudiocannotbedetermined.\par\pard\par\pard\ql\ul0\nosupersub\cf10\f11\fs20Keywords:\ul0\nosupersub\cf14\f15\fs20Stegenography,LSBMethod\par\pard\ul0\nosupersub\cf10\f11\fs201.INTRODUCTION\par

\par\ul0\nosupersub\cf6\f7\fs20Steganographyisthepracticeofhidinginformation\u8220?inplainsight\u8221?.Thistechniquereliesonamessagebeingencodedandhiddeninatransportlayerinsuchawayastomaketheexistenceofthemessageunknowntoanobserver.Importantly,thetransportlayer-thecarrierfile-isnotsecretandcanthereforebeviewedbyobserversfromwhomthesecretmessageitselfshouldbeconcealed.Thepowerofsteganographyisinhidingthesecretmessagebyobscurity,hidingitsexistenceinanon-secretfile.Inthatsense,steganographyisdifferentfromcryptography,whichinvolvesmakingthecontentofthesecretmessageunreadablewhilenotpreventingnon-intendedobserversfromlearningaboutitsexistence1.Becausethesuccessofthetechniquedependsentirelyontheabilitytohidethemessagesuchthatanobserverwouldnotsuspectitisthereatall,thegreatesteffortmustgointoensuringthatthemessageisinvisibleunlessoneknowswhattoloo

kfor.Thewayinwhichthisisdonewilldifferforthespecificmediathatareusedtohidetheinformation.Ineachcase,thevalueofasteganographicapproachcanbemeasuredbyhowmuchinformationcanbeconcealedinacarrierbeforeitbecomesdetectable,eachtechniquecanthusbethoughtofintermsofitscapacityforinformationhiding.\par TherearenumerousmethodsusedtohideinformationinsideofPicture,AudioandVideofiles.Thetwomostcommonmethodsare\ul0\nosupersub\cf10\f11\fs20LSB(LeastSignificantByte)\ul0\nosupersub\cf6\f7\fs20and\ul0\nosupersub\cf10\f11\fs20Injection.\par\pard\par\pard\ql\par\pard\paperw12240\paperh15840\par\pard\par\pard\par\pard\par\pard\ql\ul0\nosupersub\cf1\f2\fs18JournalofTheoreticalandAppliedInformationTechnology\par\pard\par\pard\ql\ul0\nosupersub\cf2\f3\fs18©2005-2009JATIT.Allrightsreserved.\par\pard\par\pard\ql\ul0\nosupersub\cf4\f5\fs18www.jatit.org\par\pard\par\pard\ql\ul0\nosupersub\cf10\f11\fs202.EXISTING

SYSTEM:\par\pard\par\pard{

\trowd\trautofit1\intbl{\ul0\nosupersub\cf6\f7\fs20TheexistingsystemofAudio}\cell{\ul0\nosupersub\cf10\f11\fs20Figure:Encoding}\cell{\trowd\trautofit1\intbl\cltxlrtb\clftsWidth1\cellx4320\cltxlrtb\clftsWidth1\cellx8640\row}

}\par\pard\par\pard\ql\ul0\nosupersub\cf6\f7\fs20Steganographyposesmorerest

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rictionsonthechoosingofaudiofiles.Usercanselectonlywavfilestoencode.Itsupportswatermarkingmethodtoencode.Itcomplexityariseswhenmoremessagetobeencoded.Themessagelengthisrestrictedto500characters.Itdoesn\u8217?tshowsthevariationsoccurredafterencodingthemessage.TheLSBalgorithmintheexistingsystemisnotefficientbecauseithidesthemessageinconsecutivebytesreceivedfromaudiofiles.\par\pard\par\pardThedisadvantagesofexistingsystemis\par \ul0\nosupersub\cf17\f18\fs20¾\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20Selectionofaudioformatsisrestrictedtoone.\par\pard\par\pard\ul0\nosupersub\cf17\f18\fs20¾\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20Non-Provisionofencryptionkey\ul0\nosupersub\cf17\f18\fs20¾\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20Lengthofthemessageislimitedto500.\ul0\nosupersub\cf17\f18\fs20¾\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20Absenceoffrequencycharttoshowthe\par variations.\par\pard\par\pard\ul0\nosupersub\cf17\f18\fs20¾\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20Lackingooduserinterface.\ul0\nosupersub\cf17\f18\fs20¾\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20Consumemuchtimetoencodeand\par decode.\par\pard\par\pard\ql\ul0\nosupersub\cf17\f18\fs20¾\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20Non-Provisionofsendingthefiletothe\par destination.\par\pard\par\pard\ql\ul0\nosupersub\cf17\f18\fs20¾\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20Userneedstounderstandbettertoknow\par theoperations.\par\pard\par\pard{

\trowd\trautofit1\intbl{\ul0\nosupersub\cf10\f11\fs20-}\cell{\ul0\nosupersub\cf

10\f11\fs20Decoding\ul0\nosupersub\cf6\f7\fs20isaprocessofretrievingthe}\cell{\trowd\trautofit1\intbl\cltxlrtb\clftsWidth1\cellx4320\cltxlrtb\clftsWidth1\cellx8640\row}

\trowd\trautofit1\intbl{\ul0\nosupersub\cf6\f7\fs20Thesearethedisadvantagesinthe}\cell\cell

{\trowd\trautofit1\intbl\cltxlrtb\clftsWidth1\cellx4320

\cltxlrtb\clftsWidth1\cellx8640\row}

\trowd\trautofit1\intbl{}\cell{\ul0\nosupersub\cf6\f7\fs20messagefromtheaudio.}\cell{\trowd\trautofit1\intbl\cltxlrtb\clftsWidth1\cellx4320\cltxlrtb\clftsWidth1\cellx8640\row}

}\par\pard\par\pard\qlexistingsystemwhichcanbeovercomebytheproposedsystem.\par\pard\par\pard\qlFigure:Decoding\par\pard\par\pard\ql\ul0\nosupersub\cf10\f11\fs203.PROPOSEDSYSTEM:\par\pard\par\pard \ul0\nosupersub\cf6\f7\f

s20EnhancedAudioSteganographyisamethodofhidingthemessageintheaudiofileofanyformats.EASprovidesaneasywayofimplementationofmechanismswhencomparedwithaudiosteganography.ApartfromtheencodinganddecodinginAudiosteganography,EAScontainextralayersofencryptionanddecryption.ThefourlayersinEASare:\par \ul0\nosupersub\cf17\f18\fs20¾\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20Encoding\par\pard\par\pard\qj\ul0\nosupersub\cf17\f18\fs20¾\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20Decoding\ul0\nosupersub\cf17\f18\fs20¾\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20Encryption\ul0\nosupersub\cf17\f18\fs20¾\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20Decryption\par\pard\par\pa

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rd{

\trowd\trautofit1\intbl{\ul0\nosupersub\cf10\f11\fs20-}\cell{\ul0\nosupersub\cf10\f11\fs20Encoding\ul0\nosupersub\cf6\f7\fs20isaprocessofhidingthe}\cell{\trowd\trautofit1\intbl\cltxlrtb\clftsWidth1\cellx4320\cltxlrtb\clftsWidth1\cellx8640\row}

\trowd\trautofit1\intbl{}\cell{\ul0\nosupersub\cf6\f7\fs20messageintheaudio.}\cell{\trowd\trautofit1\intbl\cltxlrtb\clftsWidth1\cellx4320\cltxlrtb\clftsWidth1\cellx8640\row}

}\par\pard\par\pard{

\trowd\trautofit1\intbl{\ul0\nosupersub\cf10\f11\fs20Modified}\cell{\ul0\nosupersub\cf10\f11\fs20LSB(LeastSignificant}\cell{\ul0\nosupersub\cf10\f11\fs20Bit)}\cell{\trowd\trautofit1\intbl\cltxlrtb\clftsWidth1\cellx2880

\cltxlrtb\clftsWidth1\cellx5760\cltxlrtb\clftsWidth1\cellx8640\row}

}\par\pard\par\pard\qlAlgorithm\ul0\nosupersub\cf6\f7\fs20isusedtoencodethemessageintoaudio.Itperformsbitlevelmanipulationtoencodethemessage.Thefollowingstepsare\par\pard\par\pard\ql\par\pard\paperw12240\paperh15840\par\pard\par\pard\ql\ul0\nosupersub\cf1\f2\fs18JournalofTheoreticalandAppliedInformationTechnology\par\pard\par\pard\ql\ul0\nosupersub\cf2\f3\fs18©2005-2009JATIT.Allrightsreserved.\par\pard\par\pard\ql\ul0\nosupersub\cf4\f5\fs18www.jatit.org\par\pard \ul0\nosupersub\cf6\f7\fs20a.\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20Receivestheaudiofileintheformofbytesandconvertedintobitpattern.b.\ul0\nosupersub\cf18\f19\fs20

\ul0\nosupersub\cf6\f7\fs20Eachcharacterinthemessageisconvertedinbitpattern.c.\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20ReplacestheLSBbitfromaudiowithLSBbitfromcharacterinthemessage.\par\ul0\nosupersub\cf10\f11\fs20Powerfulencryptionalgorithm\ul0\nosupersub\cf6\f7\fs20isusedtoencryptthemessagebeforeencodingforfurthersecuritypurpose.Thefollowingstepsisusedto\par\para.AddingallASCIIvaluesofcharactersin\par\parb.Convertingthesumintobitpatternc.Performinglogicaloperationtothebit\par\pard.Addingtotheencodedcharacter.\parFormoresecurityenhancementtheencodingisdoneonlywhenthebytewhichisreceivedfrom\par\par254or255.Thisselectionof\ul0\nosupersub\cf10\f11\fs203.3Encoding:\ul0\nosupersub\cf6\f7\fs20particularbytesforencodingwillreducethelackinqualityofaudioafterencoding.Itcanbeprovedbyseeingthefrequencychartindicatingthedeviationshappenedafterencode.Thoughtithas

morethanshowsbitleveldeviationsinthechartasawholethechangeintheaudiocannotbedetermined.\par\parThebasicideabehindthisistoprovideagood,efficientmethodforhidingthedatafromhackersandsenttothedestinationinsafemanner.Thoughitiswellmodulatedsoftwareithasbeenlimitedtocertainrestrictions.Thequalityofsounddependsonthesizeoftheaudiobywhichtheuserselectsandlengthofthemessage.\par\parusingpublickey.\ul0\nosupersub\cf10\f11\fs203.4Decoding:\ul0\nosupersub\cf6\f7\fs201)Sizeoffileisnotchangedafterencoding.2)Sinceitisbitlevelmanipulationthesoundvariationscannotbedeterminedbyanycurrent\par\parTheproposedsystemoverconsecutivecomesalltherestrictionsmadeontheexisting

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systems.Itprovidesgoodlookingenvironmenttouser.Italsoprovidetheusertogivesecretkeyforencryption.Thelengthofmessageismoremessage.thantheexistingsystem,andprovidesfrequencycharttoseethevariationsafterencoding.The\ul0\nosupersub\cf10\f11\fs203.5Encryption:\ul0\nosupersub\cf6\f7\fs20qualityoftheaudiodoesn\u8217?tchangevariably.Itcannotdetectthelackinqualityofsound.Theencryptionkeycanbeanycombinationofcharacters,symbols,numbers.Thekeywhichisusedforencodingisalsousedfordecoding.Thisisasecretkeywherethebothuserhavetoagree\par\par\ul0\nosupersub\cf10\f11\fs203.2Theadvantagesofproposedsystemis\par \ul0\nosupersub\cf17\f18\fs20¾\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20DifferentAudioformatsaresupportedbythesystem.byoneinthemessage,beforeencoding. \ul0\nosupersub\cf17\f18\fs20¾\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20Provisionofencryptionkeyandperformssimpleencryptionalgorithm.\ul0\nosupersub\cf17\f18\fs20¾\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20Theencryptionkeyismodifiedbyastrongalgorithmtogetanewkey,whichisusedtoencryptthemessage.Soevenifthekeyisknownforanintruder,hecannotbreakthecodewiththatkey.\ul0\nosupersub\cf17\f18\fs20¾\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20Presenceoffrequencycharttoshowthevariationsthathelpstheusertodetermine.\ul0\nosupersub\cf17\f18\fs20¾\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20Consumptionoftimetoencodeanddecodeisreduced.\ul0\nosupersub\cf17\f18\fs20¾\ul0\nosupersub\cf18\f19\fs20\ul0\nosupersub\cf6\f7\fs20ProvisionofsendingthefiletothedestinationisgivensothatafterencodingtheusercansendthefilebygivingdestinationIPaddre

ss.\par\parTheaudiofilecontainssetofbytes.For\pare.g.takeanaudiofilewhichplayfor10secs.It\par\par60,000bytes.Eachbyteisreceivedandcheckedifthereceivedbyteis254or255.Ifitisbyte255or254,encodingisdone.\par Soforonecharactertoencodeweneedeight254or255bytes.Onecharacterishiddeninconsecutiveeight254or255bytes.Inordertomarktheendofmessage,theLSBbitofnexteightconsecutive254or255byteswhichcomesafterallthemessageshaveencodedarereplaced\par 1.Beforeencoding,messageisencrypted\par\parTheencodedfileisdecodedtogetthe\parmessage.Themessageisdecodedfirstandthendecryptedbythepublickey.Theeight\par\par254or255bytesaretakenanddecryptedwiththepublickey.Thisdecryptedbytehavevaluelessthan128.Soifthevalueis255afterdecryptedthenitissaidtobeendof\par\parTheuserallowedenteringthepublickey/sharedkeyinanycombinationofnumbers,symbolsandcharacters.The

keycontainssetofcharacters.AllcharactersareconvertedtoASCIIvalueandaddalltheASCIIvaluetogetsinglenumber.Andthatsinglenumberisconvertedtobitpatternandbysimplelogicaloperation(XOR)youcangetasinglenumberlessthan128.Itisanewprivatekey.Itisaddedtothecharactersone\par\pard\par\pard\ql\par\pard\ul0\nosupersub\cf999999\f1000000\pard\fs32ATTENTION!\fs24\par\parTRIALLIMITATION-ONLY3SELECTEDPAGESMAYBECONVERTEDPERCONVERSION.\par\parPURCHASINGALICENSEREMOVESTHISLIMITATION.TODOSO,PLEASECLICKONTHEFOLLOWINGLINK:\par{\field{\*\fldinst{HYPERLINK"http://www.investintech.com/purchasea2e.html"}}{\fldrslt{\cf1\ulhttp://www.investintech.com/purchasea2e.html}}}}