In order to be able to integrate via SFTP or FTPS you have to make sure that your system can reach out to Tradeshift.
To do so please make sure that your firewall is not blocking the communication on the following host and ports:

- The host is: si.tradeshift.com

- And the SFTP/FTPS ports:

sftp.port=22 (with SSH)

ftps.port=990 (with SSL)

ftps.mode.passive.ports=2500-2699

Read more on our Integration page.