A fiber, a single filament of natural material, such as cotton, linen or wool, or artificial material such as nylon, polyester, metal or mineral fiber, or man made natural fibre like Viscose, Modal & Excel is measured in terms of linear mass density, the weight of a given length of fiber.
The vernam cipher, sometimes known as the 'one time pad', is a stream cipher, which providing certain requirements are met, can be theoretically unbreakable.
One-Time-Pad (Vernam's Cipher) Frequently Asked Questions. A one-time pad isn't a cryptosystem: it's a state of mind. - Marcus Ranum. A Russian One-time pad, captured by MI5 (click to enlarge). As a practical person, I've observed that one-time pads are theoretically unbreakable, but practically very weak.