Bilinear-map accumulator [1] is more efficient than the RSA accumulator [2] but do you know any disadvantage for the bilinear-map accumulator when compared to RSA accumulator?
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2$\begingroup$ I've added related articles. [1] is the source for Bilinear-map accumulator and [2] is the performance comparison article. $\endgroup$– kelalakaFeb 3, 2020 at 21:55
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$\begingroup$ @kelalaka verification cost is o(1) or o(n) for rsa accumulator? I am confusing about that. $\endgroup$– jhdmApr 20, 2020 at 7:12
1 Answer
I will list two disadvantages that come to mind.
A bilinear accumulator requires a public parameter which is linear in size, which means you need to have an upper bound on the number of data elements you would commit to the accumulator. The RSA accumulator requires a public parameter which is constant-sized.
A bilinear accumulator does not allow dynamic updates. If you have an accumulated digest $$A = g_1^{\prod\limits_{i=1}^N (s+d_i)}\;\;\; (s = \text{ the trapdoor}) $$ and need to insert a new element $d$, you would need to update the accumulated digest to $A^{s+d} = A^s*A^d$. But in order to compute $A^s$ without the trapdoor, you would need to know the coefficients of the polynomial $f(X):=\prod\limits_{i=1}^N (X+d_i)$. You would then compute the coefficients of $Xf(X)$ and use those to compute $A^s$. Thus, inserting a single element has a run time of $O(N)$.
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$\begingroup$ update cost in rsa dynamic accumulator is O(1). Am i right? $\endgroup$– jhdmApr 1, 2020 at 9:21
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$\begingroup$ if i cancel 5 certificate, so what is the corresponding verification cost. How can i calculate it $\endgroup$– jhdmApr 18, 2020 at 14:41
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$\begingroup$ For example if i have five revoked certificate, what is the corresponding value of verification cost? $\endgroup$– jhdmApr 18, 2020 at 14:49
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$\begingroup$ verification cost is also o(1) or o(n) for rsa accumulator? $\endgroup$– jhdmApr 19, 2020 at 16:43