Rsync run on TCP/IP?

[fred wu]

Dear All,

  I have searched the email archive but i didn't find a clear
answer(maybe I miss it) ^^

 1. Does rsync run on TCP/IP?
 2. Without ssh, then rsync will be transferred in plain text? 
 3. Does rsync support Samba? Am I true to say that rsync, which is
mainly on user authetication,  is transparent  to the storage like
ftp?

 Any help to any questions will be appreciated! Thank You!

Regards,
Fred