BulletProof FTP Server for Windows provides efficient FTP, FTPS and SFTP performance with an intuitive graphical user interface, giving administrators total control of connected users and file distribution through features such as monitoring FTP activity and traffic, providing superior user control with quotas/quotota systems/hard disk space quotota systems as well as Bandwidth Throttling/Traffic Shaping to name just a few.
This program can easily work behind firewalls and NAT (Network Address Translation) systems and handle large file transfers without interruption. Resumable uploads/downloads and compressing transferred data helps save disk space; further features include log support, chat functionality and the option to restrict certain IP addresses – making it suitable for both home computer use as well as small businesses.
Installation is fairly straightforward for this software, requiring little experience for optimal setup. Once setup is complete, a graphical user interface displays both local and remote system directories on either side. Most features of the program can be accessed directly from this screen – the only drawbacks I found being its lack of built-in site manager window often found with other FTP programs, lack of scripting capabilities and inadequate user documentation.
FTP clients connect to hosts using port 21 as a control channel between themselves and the server, with two random, unprivileged ports (let’s call them P and P+1) opened on their system to permit data connections with the server. When an FTP PASV command is sent from one client to another server, this results in port 2000 opening up an FTP data connection leading directly to port P+1 on their client system.
Passive mode is generally preferred by organizations because its control channel remains idle during directory listing data transfer and there’s no risk that a command could be sent across a data connection that would cause network problems.
Leech Mode can be enabled from the Advanced Settings menu of this program and when enabled will disconnect when your download credit runs out before reconnecting to continue downloading where it left off. This feature is particularly beneficial on websites that require that you upload at least a minimum amount before they allow downloads; however it should be noted that it does not bypass security of websites and may limit how much more can be downloaded than what has already been uploaded; furthermore this is one feature which may not support all FTP servers so should be used with caution.