Quick facts about ABTO Software's VoIP SIP SDK for Windows:

License Details

No yearly/monthly fee
No limitation for number of users, channels, or products

Protocols Support

SIP
RTP
SDP
TCP/UDP
STUN
ICE

Development Features

ActiveX, COM, and plain dll files
NAT (Network Address Translation) support
Encryption on the basis of sRTP, DLS, and DTLS
DTMF (Dual Tone Multi Frequency) support
SIP Authentication
Codecs management
Basic samples (C#, C++, VB.NET, VB 6.0, and Delphi)
Custom samples (multiple SIP accounts, IVR, presence, and voice mail)
Log file on/off setting

End User Features

All versions of Windows OS, including Windows 8
Support of all kinds of Internet connections
SIP Registrar support (compatibility with most of SIP servers including Asterisk)
Works under firewall
Multiple sip accounts registration
Multiline support
Multi-party voice conference
Video call support
IM interface
Selecting of media input and output devices
Custom ringtone support
Configuration saving and loading

Conversation Specific Features

Calls operations:

- Hold/Retrieve Call
- Forward Call (Blind Call Transfer)
- Transfer Call (Attended Transfer)

Noise reduction (supression)

- AGC (Auto gain controller) support
- Adaptive silence detection
- Adaptive jitter buffer

Software volume control (including Mute Sound)
Playing file into conversation
Recording conversation into file
Redirection of calls to other phone lines


Available codecs:

H.263
H.264
G.711 (ALaw, muLaw)
G.726 (16k 24k 32k 40k)
G.729A
G.723
iLBC
LPC-10
Speex (Narrow, Wide)
L16
GSM

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