Transfer multiple file within single connection

[mcgyver83]

Hi,
I'm running ProFtpd on a raspberry pi2 and I'm using FileZilla from mac and windows 7 laptop.

I'm using FTPS (require explicit FTP over TLS) and I want to upload 3500 files.
I see that for each file a new connection is create, handshake, authentication and so on... it takes a lot of time
Is it possible to configure FileZilla to reuse the same connection for multiple files so I can save time enstablishing connection only once?

[botg]

The way FTP works you have two types of connections: Control connections, over which commands and replies are sent, and data connections over which the actual files and directory listings are sent.

While control connections can be used for any number of commands, each individual file transfer and directory listing must use a separate data connection, which does involve the unavoidable TCP handshake and, if TLS is used, a TLS handshake. Fortunately in case of TLS, the data connection handshake is sped up massively thanks to TLS session resumption, which in this case doubles as an important security mechanism, authenticating the data connection.

[mcgyver83]

Many thanks for the reply.

Is "TLS session resumption" a server configuration? How can I leverage this in my setup?

[botg]

With secure FTP over TLS products, TLS session resumption is not a configuration option, it simply is mandatory.