, We use this preprocessing cost (the preprocessing before each trial enumeration except the initial preprocessing) as input to the pruner (for both PressedBKZ 60 and BKZ 90-reduced bases). The total pruned enumeration cost estimate in fpylll, tabulated in Table 5.1, confirms that Pressed-BKZ 60 and BKZ 90-reduced bases indeed have similar quality as they all admit similar total pruned enumeration costs. In general, the pruner seems to be quite precise in practice (hence so are the estimates in Table 5.1). Thus it suffices to compare the initial preprocessing cost between Pressed-BKZ, Here we just used BKZ 80 for simplicity (there could be other strategies). The re-preprocessing took 1.7 × 10 5 seconds (i.e., 3.4 × 10 12 nodes), vol.60

, In this subsection, we have only considered a straightforward strategy, BKZ plus enumeration, for solving the SVP-120 instance, the following we will further compare with progressive-BKZ, vol.16

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. .. Un-exemple-de-réseau-bidimensionnel-engendré-par-une-base, . Usvp, and . .. Gapsvp, IX 2 Graphique des réductions entre le problème LWE (dans le cas moyen) et certains problèmes sur les réseau

. .. Basis, 1 1.2 Graph of reductions between known the (average-case) LWE problem and some (worstcase) lattice problems: BDD, uSVP and GapSVP

. , Babai's round-off algorithm for CVP under different bases

. , A lattice in R 2 and two of its bases

. , An example of sparsification with p = 5, z = (1, 2)

A. and .. .. ,

. , An illustration of the LWE samples

.. .. Experiment,

. , Quantum circuit for evaluating a function f with input |x

. .. , 28 2.9 Comparison of run-time and SVP approximation factor between LLL-reduction, BKZreduction and HKZ-reduction, An illustration of DCP samples with modulus N = 14

. .. , Comparison between prior reductions from BDD ? to uSVP ? , and ours, p.45

. , An example of sparsification for BDD 1/2 (here w ? ? p,z /?)

. , ? 2) instance, BDD, vol.1, issue.2

. , Geometric illustration of the reduction

. , 57 4.2 A comparison between our solver (via our LWE to EDCP reduction and solving LWE by the LLL algorithm) and the Childs and van Dam's solver for solving EDCP, An illustration of one-dimensional U-EDCP with number of possibilities 2, 4 and 6, and, p.59

. , Graph of reductions between the LWE problem, the EDCP problem, chosen worst-case lattice problems

. , A visualization of the space subdivision

. , A visualization of the balls' intersections

, Graph of reductions between U-EDCP, G-EDCP and LWE with parameter losses, p.64

. , Quantum circuit for our reduction from LWE to EDCP

G. To and L. .. ,

. , Gram-Schmidt log-norms for BKZ 45 at tour 2, 000

. , 10 Evolution of the Gram-Schmidt log-norms during BKZ 40 's execution, BKZ 40 , BKZ 50 and BKZ 60 on a BKZ 40 reduced basis, vol.87, p.88

. , Evolution of the b * i /GH's during BKZ 40 's execution

. , Evolution of Root Hermite factors during the execution of BKZ 45

. , Output Gram-Schmidt log-norms for BKZ 40 with pruning

, Evolution of the b * i /GH's during the execution of BKZ 60 with pruning, p.91

. , Gram-Schmidt log-norms for BKZ 45 at tour 50

. , Same as Figuer 5.15, but zoomed in

. , Gram-Schmidt log-norms for BKZ 45 at tour 2, 000

. , Gram-Schmidt log-norms for BKZ 60 at tour 50

. , BKZ, vol.60, issue.20

. , 99 5.23 Evolution of the root Hermite factor during the execution of BKZ 45 (no pruned enumeration) on SVP-100

. , 100 5.25 Comparison of Gram-Schmidt log-norms obtained by the simulators and BKZ 60 (no pre-processing) on SVP-150, after 4,000 tours, Evolution of the root Hermite factor during the execution of BKZ 60 (with pruned enumeration) on SVP-150

, Root Hermite factor for selected ? ? {50, 60, · · · , 300}. Here the dimension is 3 · ?, p.102

, Full sequences of Gram-Schmidt log-norms of bases returned by BKZ 60 and pressed-BKZ 60, p.104

. , Full sequences of Gram-Schmidt log-norms of bases returned by BKZ 60 , pressed-BKZ 60 and simulated pressed-BKZ 60

·. and 3. , Here the dimension is 1000 for ?, Comparison between our simulator for pressed-BKZ and the Chen-Nguyen simulator for standard BKZ for selected ? ? {50, vol.60, 2000.

, Comparison between our simulator for pressed-BKZ and the Chen-Nguyen simulator for standard BKZ for selected ? ? {50, 60, · · · , 300}. Here the dimension is 3 · ?, p.106

, Comparison of root Hermite factors of simulated BKZ with and without variable blocksize. The simulation is performed with our new simulator up to 40 tours, p.107

, Comparison of root Hermite factors of simulated BKZ with and without variable blocksize. The simulation is performed with our new simulator up to 2,000 tours, p.108

. , Comparison of root Hermite factors of standard BKZ 60 with and without variable blocksize within 40 tours

. , 109 5.37 Gram-Schmidt log-norms of experimental pressed-BKZ 60 and BKZ 90 (28 tours).. .. . 111 5.36 Gram-Schmidt log-norms of simulated pressed-BKZ 60 and simulated BKZ ?, Comparison of root Hermite factors of standard BKZ 60 with and without variable blocksize within 2,000 tours, p.111

. .. , 112 1 Partition algorithm for exponentially approximated first minimum

. , Regev's public key encryption scheme

. , Size-reduction algorithm

T. Schnorr and .. .. ,

.. .. The,

T. Chen-nguyen and .. .. Bkz-simulator,

.. .. The,