Video conferencing Using SIP protocol and C#

Question

 hi Everybody,

                  I am new to SIP and C#.  Now i  attempting to create video conferencing Using SIP and C#.
But i dont know how to create SIP server and how to stream video .
  
    Could you please tell me how to do that?
or
Give me some links about video conferencing

sorry for my poor english

Thank you ,

Senthil.P