DES / AES program
How do I turn in my program?
When make has been executed it should be possible to encrypt
using the command des (or aes).
- Make a subdirectory with the same name as your username.
- Put your sourcefile(s), a Makefile, a README file, and, if you
use Java, a shell script in this directory.
- When in this directory, typing make should build your program with
whatever compiler, linker, and switches you choose.
The README file should include your name and
state an estimate of your algorithm's
encryption speed (in bytes of plaintext per second).
You can also include any other information you consider
- for Java solutions: a shellscript "des" or "aes" with the line
java Encrypt $*
(assuming your main class is called Encrypt). If you want to
start java with any switches, include them in the above command.
- Make a gzipped tar file from the directory (see below).
- Send firstname.lastname@example.org an email where the subject states whether it is
DES or AES, and where you include the compressed tarfile as an
The input files will consist of a large number of bytes where 8 bytes
make a DES-block and 16 bytes make an AES block. The first byte in the
input is the first ("leftmostmost") byte in the first DES/AES block
and so on. If you are not developing the program on a SUN, beware of
endiean problems. The files are not terminated by a newline or any
other special characeter.
In order for your program to be a candidate for
fastest encryption it must be turned in on time.
How is it going to be tested?
Your program will be built using your makefile. If you are using
Java, I will use the module jdk/latest (jdk/1.4.0). If you want
something else modify the make-file and the shellscript
accordingly. Similarly, for gcc and g++ I will use gcc/3.1.
The programs will be tested both for correctness and speed by
running them on several input files. The files will be stored
locally on computer.
Time will be measured by considering user time and system time
as indicated by /usr/bin/time on a Sun Blade 100. The input
files will typically be from about 1 Mbyte to 10 Mbyte in
size. When determining the fastest program, larger files may be
used (roughly enough to make the prgram run for about five
Note that I want to be able to write
/usr/bin/time des deskey < infile > outfile
(or /usr/bin/time aes aeskey < infile > outfile).
How will results be announced?
Results for the fastest programs will be posted on the course web
page. Assuming the
winners (one for DES, one for AES) do not mind, their names and
code will also be posted.
When you present your solutions you will also get the results
for your program. You can of course get a pretty good idea by
running time on it yourself.
How do I construct the gzipped tar-file?
For instance, if I (migo) had a C-program called des.c, I would
make a subdirectory called migo/ and therein put my README
file, the file des.c and a makefile.
The gzipped tar-file migo.tar.gz is created by the commands
tar cf migo.tar migo
excecuted in the directory that contains migo/.
The makefile might simply contain the following lines (note
that the second line starts with a tab):
gcc -O4 des.c -o des
Last modified: Tue Apr 16 10:15:01 MEST 2002