| Overhead | Approach type | Error method |
| One or more bits add to the character | ARQ | Parity bit |
| One bit per character plus LRC character | ARQ/FEC | LRC |
| Checksum character at end of message | ARQ | Checksum |
| CRC bytes at end of message | ARQ | CRC |
| Hamming bits inserted into data stream | ARQ/FEC | Hamming code |
| One bit per character plus signature character | ARQ/FEC | Signature |