Side Channel Attack

Question 1

First observation of side-channels

Answer 1

Partially declassified 1972 NSA document:
In 1943 Bell Labs employees working on encryption
systems noted that whenever the system is activated, spikes appeared on an oscilloscope in another part of the lab, which could be interpreted to recover the plaintext
data.

In 1950s British intelligence agents listened to the
resetting of the key wheels of Egyptian encryption
machine to deduce their starting positions, which enabled
them to crack the encryption.

Question 2

FLUKE 87V

Answer 2

The industry’s standard
multimeter
 Can measure current
directly
 Slow Sample Rate
(kS/s)
 Single Channel

Question 3

Modular Exponentiation

Answer 3

Modular arithmetic: finding the remainder
 7 ÷ 2 = 3 with remainder 1
 7 ≡ 1 (mod 2): 7 is congruent to 1 modulo 2
 a ≡ b (mod n): a-b = n * k for some integer k

Modular exponentiation:
 a
e ≡ ? (mod n)
 2
4 ≡ 6 (mod 10) because 24 = 16
 3498731710357198 ≡ ? (mod 510927533897)