ECM (Error Correction Mode) – Definition

LAST UPDATE: March 2nd, 2019


Error correction mode (ECM) is a feature in a fax that corrects errors in the fax transmission from bad phone connections.


The most common error is in a fax transmission is telephone line noise, which can distort the image of a fax.

With a noisy phone line, ECM can result in a higher success rate for fax transmissions.

ECM is sometimes turned off for attempting to fax over a digital phone line (such as a VoIP phone line).

How it works

ECM works in a way that is similar to an internet transmission.

With ECM enabled, the fax transmission is broken into small chunks of data. As each piece of data is sent, a confirmation of whether it was received or not is returned. Any parts of the transmission that are not fully received are sent again.

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