File line ending not changed to CR LF by Windows FTP server and client

I downloaded one file (created with Linux line end character "LF") from Windows 10 to Windows 7 using ftp.

After downloading in Windows 7 from Windows 10, that file line end character has not changed to "CR LF".

I downloaded using "type ASCII" mode only. Why has line ending not changed to CR LF?

I have used IIS Windows FTP server. And client is Windows ftp client.

Also please explain, whether the line ending conversion (from LF to CR LF or CR LF to LF) is done by FTP server ot FTP client.

I checked in RFC protocol also, no clear definition.

Solution

In the ASCII mode, the server converts the file from its native format to canonical format specified by RFC 959 (section 3.1.1.1. ASCII TYPE). The canonical format is ASCII plain text format with CRLF line endings.

The client then converts the file from the canonical format to its native format.

As the FTP canonical format matches that of the Windows, it's quite probable that both Windows server and client actually transfer the files without any modification.