Computer Networks
Prac Exercises #17
- If you've got a bit of spare time (;-) try writing
a small program to implement XOR encryption.
You should be able to do a minimal one in just a few
lines of C, maybe a few more for C++ people.
- Investigate the Unix crypt utility.
- In the lecture, the risks of using TELNET to log in across
an insecure network were mentioned. One solution to this is to
use the ssh utility, available on all of the departmental
Unix systems, and also available for PCs (I'm not sure about
Macs). Investigate what ssh can do for you.
- Even if you're not tackling Q.4 of assignment 3, you should be aware of
the pgp utility available on the department Unix systems. Run pgp
and see what it tells you in its usage message. Note that PGP is
also widely (and freely) available for PCs and Macs.
- Investigate skey, available on our departmental Unix
systems. What problem does it attempt to solve?
- Follow some of these cryptography links
and learn about the history, the politics and the evolution of
cryptography.
[Previous Tutorial]
[Tutorial Index]
[Next Tutorial]
Phil Scott