Hi,

I need to make a VoIP program. This program is basically just a
client/server program that is able to make PC to PC call, and also call any
VoIP enabled devices. I am NOT need implementing a VoIP service provider,
i.e. the Gatekeeper, etc. I guess is more like MS Netmeeting.

I am using C# to do this. Can anyone advice me where ca I get started? Does
.Net or Microsoft has any related technologies that suit my needs? Any third
party technologies that related to this?

Any help will be appreciated. And hopefully I can get some sites that help
me get started.
Thanks in advance.

Thomas.

You can use TAPI3 [1], Netmeeting SDK [2] and/or Messenger SDK [3]
(high-level api). Or implement it yourself - sockets and multimedia API
(P/Invoke).

[1]
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/tapi...
tapi_3_1_start_page.asp?frame=true
[2] http://www.microsoft.com/windows/NetMeeting/Authors/default.ASP
[3]
http://msdn.microsoft.com/downloads/default.asp?url=/downloads/topic....
=/MSDN-FILES/028/001/359/topic.xml&frame=true

HTH,
AlexK

[Please don't multi-post]

currently H.323 and TAPI
  http://msdn.microsoft.com/library/en-us/tapi/tapi3/microsoft_telephon...
  http://msdn.microsoft.com/library/en-us/dntapi/html/msdn_tapi_30.asp
  http://www.microsoft.com/technet/prodtechnol/winxppro/reskit/prdk_tel...
TAPI is not included in .NET 1.0, but you could use the VB COM Type-Lib:
   (TAPI3Lib, "Microsoft TAPI 3.0 Type Library", c:\windows\system32\tapi3.dll ).
I don't know if this works for VoIP.

But I guess the future is SIP / IM / RTC.
It is currently available in Windows XP messenger.

Please check old RTC C# sample:
  http://msdn.microsoft.com/downloads/sample.asp?url=/MSDN-FILES/027/00...
  (Note: was for a .NET RC version, may be you can't use it unchanged)
I had this running peer-to-peer (XP-to-XP) even with video.

You should also read the SDK documentation
  http://msdn.microsoft.com/library/en-us/rtcclnt/rtc/real_time_communi...

Newsgroup:
  microsoft.public.win32.programmer.rtc

[unofficial] Microsoft will release a SIP server product named 'Greenwich':
  http://www.eweek.com/article2/0,3959,526566,00.asp

--
 Thomas Scheidegger - MVP .NET - 'NETMaster'
 http://www.cetus-links.org/oo_dotnet.html - http://dnetmaster.net/