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== Installing PBC ==
The PBC library needs http://www.swox.com/gmp/[the GMP library].
This build system has been tested and works on Linux and Mac OS X with a
fink installation.
$ ./configure
$ make
$ make install
On Windows, the configure command requires a couple of options:
$ ./configure -disable-static -enable-shared
By default the library is installed in `/usr/local/lib`. On some systems, this
may not be in the library path. One way to fix this is to edit
`/etc/ld.so.conf` and run `ldconfig`.
=== Simple Makefile ===
For speed and simplicity, I use `simple.make` during development.
Naturally it is less portable.
$ make -f simple.make
PBC uses some GNU C extensions such as nested functions.
[[pbcintro]]
=== Quick start ===
We shall use the following notation. For our purposes, the pairing is a
bilinear map from two cyclic groups, G1 and G2 to a third group GT, where each
group has prime order r.
Run `pbc/pbc` and type:
g := rnd(G1);
g;
The first line generates a random element g of the group G1,
while the second prints out the value of g. (The syntax was influenced
by `bc`, an arbitrary precision calculator.)
Next, enter:
h := rnd(G2);
h;
This assigns h to a random element of the group G2. Actually, the default
pairing `pbc` uses is symmetric so G1 and G2 are in fact the same group, but in
general they are distinct. To compute the pairing applied to g and h, type:
pairing(g,h);
The order of both g and h is r. Let's generate two random numbers between
1 and r:
a := rnd(Zr);
b := rnd(Zr);
By bilinearity, the resulting output of both of these lines should be
identical:
pairing(g^a,h^b);
pairing(g,h)^(a*b);
This program has <<pbcref, other features>> but the commands shown here should
be enough to quickly and interactively experiment with many pairing-based
cryptosystems using real numbers.
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