Types

• The Tin Can protocol comes in two speeds: low speed and high speed. The low-speed protocol sends 100 bits per seconds and the high-speed protocol sends 600 bits per second. They both group data into 8-bit words with one parity bit, which is a check bit to ensure that the word got through correctly.
  
  

Low-Speed Protocol

• Low-speed protocol transmits signals in two frequencies: 800Hz and 1600Hz. This is the way the 0s and 1s respectively are encoded. Like high-speed protocol, a signal starts with a transmission of eights 1s to let the receiver synchronize with the sender before the actual date is transmitted.
  
  

High-Speed Protocol

• High-speed protocol transmits signals in two frequencies: 2666Hz and 4000Hz. Using two different frequencies to encode 1s and 0s is called Frequency-Shift Keying. It is easy to implement with two oscillators in the sender and a Fast Fourier Transform in the receiver. These are both well tested electronic technologies.