TY  - JOUR
AU  - Wiechers, C.
AU  - Lydersen, L.
AU  - Wittmann, C.
AU  - Elser, D.
AU  - Skaar, J.
AU  - Marquardt, Ch
AU  - Makarov, V.
AU  - Leuchs, G.
PY  - 2011
DA  - 2011//
TI  - After-gate attack on a quantum cryptosystem
JO  - New J. Phys.
SP  - 14
VL  - 13
IS  - 1
KW  - quantum cryptography
KW  - hacking
KW  - interception
KW  - attack
KW  - SPD
KW  - APD
KW  - QKD
AB  - We present a method to control the detection events in quantum key distribution systems that use gated single-photon detectors. We employ bright pulses as faked states, timed to arrive at the avalanche photodiodes outside the activation time. The attack can remain unnoticed, since the faked states do not increase the error rate per se. This allows for an intercept-resend attack, where an eavesdropper transfers her detection events to the legitimate receiver without causing any errors. As a side effect, afterpulses, originating from accumulated charge carriers in the detectors, increase the error rate. We have experimentally tested detectors of the system id3110 (Clavis2) from ID Quantique. We identify the parameter regime in which the attack is feasible despite the side effect. Furthermore, we outline how simple modifications in the implementation can make the device immune to this attack.
N1  - exported from refbase (https://db.rplab.ru/refbase/show.php?record=730), last updated on Sun, 22 May 2016 17:42:26 -0500
ID  - Wiechers_etal2011
ER  -