Although EazyLink offers more features, YMODEM file transfers can triple its maximum speed, achieving 3K/sec at 38400bps regardless of OZ version. This is because the YMODEM implementation does not use the OZ serial driver, so it is not limited to lower baud rates by the driver issues in the original Cambridge ROM versions. By increasing the block size from 128K to 1K and batching files together, YMODEM increases efficiency.
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