How to remove power in a modular exponent expression?












0












$begingroup$


I am implementing a cryptography scheme which involves verifiying some data through the following process:




Suppose party A wants to verify data held by party B

Party A has: $a^x mod N$
Party B has: $x^{-1}$ i.e. modular inverse of $x$ with respect
to some $p$ such that $xx^{-1} equiv 1 mod p$






To carry out the verification, B has to use $a^x bmod N$ and $x^{-1}$ to attempt creating $abmod N$

If $x^{-1}$ is correctly calculated, then the data held by B is verified.

My question is, how can I, using $a^x bmod N$ and modular inverse $x^{-1}$ attempt to generate $abmod N$










share|cite|improve this question











$endgroup$












  • $begingroup$
    Based on the cryptgraphic scheme detailed here: link.springer.com/chapter/10.1007/0-387-34805-0_20
    $endgroup$
    – Tabish Mir
    Jan 28 at 7:20






  • 2




    $begingroup$
    Given y, it's quick to get y inverse mod p by the euclidean algorithm on p, y. So take x inverse, compute x, then you know the exponent used
    $endgroup$
    – Artimis Fowl
    Jan 28 at 7:25










  • $begingroup$
    x is a confidential value only to be known by B. As such, A attempts to regenerate a mod N using his version of x, a^x mod N and the corresponding x inverse. If 'x' held by B is valid, he should be able to successfully generate a mod N
    $endgroup$
    – Tabish Mir
    Jan 28 at 7:32
















0












$begingroup$


I am implementing a cryptography scheme which involves verifiying some data through the following process:




Suppose party A wants to verify data held by party B

Party A has: $a^x mod N$
Party B has: $x^{-1}$ i.e. modular inverse of $x$ with respect
to some $p$ such that $xx^{-1} equiv 1 mod p$






To carry out the verification, B has to use $a^x bmod N$ and $x^{-1}$ to attempt creating $abmod N$

If $x^{-1}$ is correctly calculated, then the data held by B is verified.

My question is, how can I, using $a^x bmod N$ and modular inverse $x^{-1}$ attempt to generate $abmod N$










share|cite|improve this question











$endgroup$












  • $begingroup$
    Based on the cryptgraphic scheme detailed here: link.springer.com/chapter/10.1007/0-387-34805-0_20
    $endgroup$
    – Tabish Mir
    Jan 28 at 7:20






  • 2




    $begingroup$
    Given y, it's quick to get y inverse mod p by the euclidean algorithm on p, y. So take x inverse, compute x, then you know the exponent used
    $endgroup$
    – Artimis Fowl
    Jan 28 at 7:25










  • $begingroup$
    x is a confidential value only to be known by B. As such, A attempts to regenerate a mod N using his version of x, a^x mod N and the corresponding x inverse. If 'x' held by B is valid, he should be able to successfully generate a mod N
    $endgroup$
    – Tabish Mir
    Jan 28 at 7:32














0












0








0





$begingroup$


I am implementing a cryptography scheme which involves verifiying some data through the following process:




Suppose party A wants to verify data held by party B

Party A has: $a^x mod N$
Party B has: $x^{-1}$ i.e. modular inverse of $x$ with respect
to some $p$ such that $xx^{-1} equiv 1 mod p$






To carry out the verification, B has to use $a^x bmod N$ and $x^{-1}$ to attempt creating $abmod N$

If $x^{-1}$ is correctly calculated, then the data held by B is verified.

My question is, how can I, using $a^x bmod N$ and modular inverse $x^{-1}$ attempt to generate $abmod N$










share|cite|improve this question











$endgroup$




I am implementing a cryptography scheme which involves verifiying some data through the following process:




Suppose party A wants to verify data held by party B

Party A has: $a^x mod N$
Party B has: $x^{-1}$ i.e. modular inverse of $x$ with respect
to some $p$ such that $xx^{-1} equiv 1 mod p$






To carry out the verification, B has to use $a^x bmod N$ and $x^{-1}$ to attempt creating $abmod N$

If $x^{-1}$ is correctly calculated, then the data held by B is verified.

My question is, how can I, using $a^x bmod N$ and modular inverse $x^{-1}$ attempt to generate $abmod N$







modular-arithmetic exponentiation






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Jan 28 at 9:38









Bernard

123k741117




123k741117










asked Jan 28 at 7:20









Tabish MirTabish Mir

12617




12617












  • $begingroup$
    Based on the cryptgraphic scheme detailed here: link.springer.com/chapter/10.1007/0-387-34805-0_20
    $endgroup$
    – Tabish Mir
    Jan 28 at 7:20






  • 2




    $begingroup$
    Given y, it's quick to get y inverse mod p by the euclidean algorithm on p, y. So take x inverse, compute x, then you know the exponent used
    $endgroup$
    – Artimis Fowl
    Jan 28 at 7:25










  • $begingroup$
    x is a confidential value only to be known by B. As such, A attempts to regenerate a mod N using his version of x, a^x mod N and the corresponding x inverse. If 'x' held by B is valid, he should be able to successfully generate a mod N
    $endgroup$
    – Tabish Mir
    Jan 28 at 7:32


















  • $begingroup$
    Based on the cryptgraphic scheme detailed here: link.springer.com/chapter/10.1007/0-387-34805-0_20
    $endgroup$
    – Tabish Mir
    Jan 28 at 7:20






  • 2




    $begingroup$
    Given y, it's quick to get y inverse mod p by the euclidean algorithm on p, y. So take x inverse, compute x, then you know the exponent used
    $endgroup$
    – Artimis Fowl
    Jan 28 at 7:25










  • $begingroup$
    x is a confidential value only to be known by B. As such, A attempts to regenerate a mod N using his version of x, a^x mod N and the corresponding x inverse. If 'x' held by B is valid, he should be able to successfully generate a mod N
    $endgroup$
    – Tabish Mir
    Jan 28 at 7:32
















$begingroup$
Based on the cryptgraphic scheme detailed here: link.springer.com/chapter/10.1007/0-387-34805-0_20
$endgroup$
– Tabish Mir
Jan 28 at 7:20




$begingroup$
Based on the cryptgraphic scheme detailed here: link.springer.com/chapter/10.1007/0-387-34805-0_20
$endgroup$
– Tabish Mir
Jan 28 at 7:20




2




2




$begingroup$
Given y, it's quick to get y inverse mod p by the euclidean algorithm on p, y. So take x inverse, compute x, then you know the exponent used
$endgroup$
– Artimis Fowl
Jan 28 at 7:25




$begingroup$
Given y, it's quick to get y inverse mod p by the euclidean algorithm on p, y. So take x inverse, compute x, then you know the exponent used
$endgroup$
– Artimis Fowl
Jan 28 at 7:25












$begingroup$
x is a confidential value only to be known by B. As such, A attempts to regenerate a mod N using his version of x, a^x mod N and the corresponding x inverse. If 'x' held by B is valid, he should be able to successfully generate a mod N
$endgroup$
– Tabish Mir
Jan 28 at 7:32




$begingroup$
x is a confidential value only to be known by B. As such, A attempts to regenerate a mod N using his version of x, a^x mod N and the corresponding x inverse. If 'x' held by B is valid, he should be able to successfully generate a mod N
$endgroup$
– Tabish Mir
Jan 28 at 7:32










0






active

oldest

votes











Your Answer





StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");

StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});


}
});














draft saved

draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3090577%2fhow-to-remove-power-in-a-modular-exponent-expression%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown

























0






active

oldest

votes








0






active

oldest

votes









active

oldest

votes






active

oldest

votes
















draft saved

draft discarded




















































Thanks for contributing an answer to Mathematics Stack Exchange!


  • Please be sure to answer the question. Provide details and share your research!

But avoid



  • Asking for help, clarification, or responding to other answers.

  • Making statements based on opinion; back them up with references or personal experience.


Use MathJax to format equations. MathJax reference.


To learn more, see our tips on writing great answers.




draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3090577%2fhow-to-remove-power-in-a-modular-exponent-expression%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown





















































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown

































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown







Popular posts from this blog

Can a sorcerer learn a 5th-level spell early by creating spell slots using the Font of Magic feature?

ts Property 'filter' does not exist on type '{}'

Notepad++ export/extract a list of installed plugins