Cryptography Reference
In-Depth Information
make no mention of information hiding, as its applications do not seem
to fit prevalent taxonomies of the field.14
14
Yet the relationship between the
two has continued to generate new problems and solutions, including
unforeseen types of attacks on ciphers, applications in the field of copy-
right protection, as well as the highly innovative work of David Chaum
on transactional anonymity, which will be explored in more detail in
chapter 3.
Telegraph
Much like would later happen with the emergence of Internet-based com-
munications, the rise of telegraphic communication services was accom-
panied by public concerns over the fact that messages circulated in the
clear, openly available to view by service providers, operators, or anyone
else who cared to tap the wires.
15
Only one year after Morse sent his first
message, his lawyer and promotional agent published the first commercial
code specifically designed to protect the privacy of telegraphic communica-
tions.
16
The security of such codes was relative, because anyone could
purchase them, but as Kahn points out, they “afforded sufficient security
for most business transactions by simply precluding an at-sight compre-
hension of the meaning.”
17
Perhaps more important, they reduced costs
by replacing whole sentences with single words, a practice much frowned
upon by the telegraph operators.
18
The impact of the telegraph on cryptography would be most felt in the
theater of the American Civil War as part of a new kind of warfare based
on massive modern armies, raised through conscription and coordinated
through modern communication and transportation technologies: “The
telegraph enabled commanders, for the first time in history, to exert instan-
taneous and continuous control over great masses of men spread over large
areas.”
19
Such control could be exerted only if messages were protected
from eavesdropping, elevating cryptography to the role of vital instrument
of warfare it hasn't lost since. The specific needs of mobile armies spelled
the end of the nomenclator, though. Its capture in the field required
issuing new codebooks to every military communication outpost, a process
much too slow and cumbersome for battle conditions. Ciphers, such as the
Vigenère, proved more appropriate as their procedures could be printed
