Bandwidth throttling provides the ability to limit the rate at which a user can download an asset. This capability is controlled by the ec_rate and ec_prebuf parameters. Typically, these parameters are specified as query string parameters. However, if you would like to encrypt these parameters, then you will need to generate a token value that includes the desired values for these parameters. By preventing a user from altering the values assigned to these parameters, you can ensure that data downloads are throttled to the desired level.
Learn more about the Bandwidth Throttling feature.
Both of these parameters are not available from the Encrypt Tool section of the Token Auth page. However, you can still generate an encrypted token value by using the Token Generator application or by creating your own token generator.