Endwall's Comment: This really is usable in the situation where you have limited computational power....like with an 8 bit computer for instance. you could use a floppy disk as the pad, and copy it and give it to your counter party for a year's worth of real time instant messaging over the telephone line. Every used block should be overwritten with a null character or zeroed out so that the program knows were to seek to for the next decryption block. This crypto-system is optimal to use with an 8-bit computer over the telephone lines. The computations are simple. This could be programmed in a weekend. Find or demonstrate working examples of this over the telephone modem on a Commodore 64 and post back here (working code or videos of it working).
https://en.wikipedia.org/wiki/One-time_pad
"Starting in 1988, the African National Congress (ANC) used disk-based one-time pads as part of a secure communication system between ANC leaders outside South Africa and in-country operatives as part of Operation Vula[28], a successful effort to build a resistance network inside South Africa. Random numbers on the disk were erased after use. A Belgian airline stewardess acted as courier to bring in the pad disks. A regular resupply of new disks was needed as they were used up fairly quickly. One problem with the system was that it could not be used for secure data storage. Later Vula added a stream cipher keyed by book codes to solve this problem.[29]"
Apparently not an original idea, even Africans were smart enough to go to this level...