Beads are notoriously difficult to find an origin for - many are made in cottage type industries.
They only really require lampwork.
Canes can be bought commercially from wherever makes them.
I have been told (by the folk on antiques roadshow), that beads with black centres, ones made on copper wires, are more likely to be from the Venetian area than beads with chalky white centres, which tend to be from around Prague - but remember - they're not terribly far apart.
Your main string looks a bit like one cobbled together from beads from various sources and ages.
If you find beads on a knotted string, they are more likely to be original - as are beads on wires. The best thing to find them on is square-sectioned gold wires.
There are old beads, made from canes, which are of Indian origins. They tend to be very large.
Beads sell well, but based mostly on decorative value rather than anybody knowing where on earth they came from or who made them.