As of version 220.127.116.11 released in August 2021 DidiSoft OraSFTP offered ZLIB compression which greatly increased the speed of the SFTP communication.
Unfortunately, the ZLIB package we used (JZlib) had a bug that resulted in ArrayIndexOutOfBoundsException on random occasions. This is very strange as this is the only Java ZLIB package with partial flush capabilities (the built into JDK Deflater doesn’t support partial flush) and it should be very robust as it is used virtually in every Java-based system with SFTP support.
After some recent investigation, we have fixed this bug in JZlib and it is available in version 18.104.22.168 of OraSFTP.
Recommended upgrade to OraSFTP version 22.214.171.124
If you are using DidiSoft OraSFTP from version 126.96.36.199 to 188.8.131.52 it is recommended to update to version 184.108.40.206 in order to have a smooth operation in ZLIB compression mode.