Friday, 29 March 2024, 05:40 AM
Site:
Webmaster Technology InstituteCourse:
Webmaster Technology Institute (AWS)Glossary:
Global Technical GlossaryY
Y-Modem
: Also known as: Ymodem Y-Modem is an
error-correction protocol used in the transfer of serial data files
between modems. Y-Modem is based on the earlier X-Modem protocol,
but has the additional feature of being able to cope with a batch
transmission mode, in which a number of files can be sent with one
command. For greater efficiency Y-Modem can also handle data with a
variable block size of up to a maximum 1024 bytes (1 kB). During
transmission, the size of text and binary files is included in the
Y-Modem header, so that the exact file length will be retained
after transfer. The error detection method in Y-Modem is cyclic
redundancy check (CRC). A later version of Y-Modem, Y-Modem-G,
transmits data in a continuous stream and does not acknowledge the
blocks successfully received; it is only the blocks with detected
errors that cause a negative acknowledgement (NAK), thus prompting
the resending of data |
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