control number of simultaneous file-PART(THREAD) and FILE connections

[rezakhaniki]

Hi,
Please let me ask a simple technical question. It is not a bug or problem with filezilla; It is more technical behavior of Filezilla Client and a FTP server like Filezilla Server.
As the subject can goes in different ways; Please let me explain my qestion in three sub parts. I'm sure the answer is such easy for Filezilla technical guys (but much important for me).

We have two different conception is FTP conections:
1. Number of parallel connections in term of file to a server
(If I'm right the maximum number of files at the same time can be define in the Server like Filzeilla-server; as well we can limit it in the client too like filezilla-client between 1 and 10)

2. Number of simultaneous connection (threads) for a file; which means during Doanload/Upload a file; the file can be seperated in N-parts (N threads)and each part be downloaded in parallel with other parts.
This subject can be see in clear in FTP clients like DAP(download accelerator Plus) in loawer part of DL window; but n Filezilla can not be seen.
I didn't see such definition in Filezilla client or server for clustering a file and donwloading it in parrallel. (please don't donfond this subject with parralell download/upload of sever files (in part.1)

Regarding to part.1 it is clear that both in Server and client we can define the maximum number of parralel files (number of parallel simultaneous file connection) at the same time and surely server limit overcomes the client limit)

QUESTION:
Regarding to part.2,

May I know if it is Server or client (or both) that activates possiblity of slotting a file for DL/UL ? (I call that number of parallel simultaneous parts OR Thread)

Why Can not I see this value in the Filezilla client or Server ?

If it is not clear such option for the users; May i know what is written as code in filezilla Server or client or both for this subject ?

If it is automatically controlled by Client or Server as advanced feature; May I know how it is controlled and how I can limit it on a fix value ?

(please don't confond it with number of parallel files)
(DAP window shows such possibility, so for me it exists)
(for me DOS command FTP; performs DL or UL with just 1 file at the moment and with 1 thread)
(please take into account that my target is not proving that we go to highest throughput. More I want to know how it is controlled and can be set; for example if I want to do DL/UL just with 1 file in 1 thread. So the subject is just managing the session)

The plaform can be considerd windows 7, vista or XP. It seems in recent versions of Filezilla, such option doesn't exist more.

Thanks in advance for your answers and support. Best Regards,