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OZEKI VoIP SIP SDK for Windows 8, Windows 7, Vista, 200x, XP

Name:OZEKI VoIP SIP SDK v10.1.14
Updated: 2014.08.22.
Download:VoIP_SDK-10.1.14.zip  (95.3 MB) 
Changes:
  1. Improvement in TCP stream handling
Name:OZEKI VoIP SIP SDK v10.1.13
Updated: 2014.06.13.
Download:VoIP_SDK-10.1.13.zip  (95.3 MB) 
Changes:
  1. New feature: Contact Id protocol support
Name:OZEKI VoIP SIP SDK v10.1.12
Updated: 2014.05.19.
Download:VoIP_SDK-10.1.12.zip  (95.1 MB) 
Changes:
  1. The aggregated H264 NAL unit is supported in RTP stream
  2. Registration issue is fixed in Asterisk based PBXes
Name:OZEKI VoIP SIP SDK v10.1.11
Updated: 2014.05.13.
Download:VoIP_SDK-10.1.11.zip  (95.1 MB) 
Changes:
  1. SIP register compatibility with VOS2000/3000 PBX
  2. Answering machine detector related bugfixes
  3. SIP reason phrase can be accessed when error occurred during a call
Name:OZEKI VoIP SIP SDK v10.1.10
Updated: 2014.04.30.
Download:VoIP_SDK-10.1.10.zip  (95.1 MB) 
Changes:
  1. Improved compatibility with SIP devices without 'rport' support
  2. Improved video recording with H.263 codec
Name:OZEKI VoIP SIP SDK v10.1.9
Updated: 2014.04.18.
Download:VoIP_SDK-10.1.9.zip  (95.1 MB) 
Changes:
  1. Minor SIP related bugfixes
Name:OZEKI VoIP SIP SDK v10.1.8
Updated: 2014.03.11.
Download:VoIP_SDK-10.1.8.zip  (95.1 MB) 
Changes:
  1. Incoming RTP data can be accessed in audio and video handlers
  2. Improvement in VAD filter
  3. UTF-8 character encoding support in SIP messages
Name:OZEKI VoIP SIP SDK v10.1.7
Updated: 2014.02.18.
Download:VoIP_SDK-10.1.7.zip  (94.8 MB) 
Changes:
  1. Improvement in dial plan: new destination types introduced (reject, redirection)
  2. Minor bugfixes
Name:OZEKI VoIP SIP SDK v10.1.6
Updated: 2014.01.31.
Download:VoIP_SDK-10.1.6.zip  (94.8 MB) 
Changes:
  1. New feature: Video recording
  2. Improvement in video and audio synchronizing
  3. Fixed SIP port can be specified when creating the IPhoneLine
  4. PBX relay mode can be set when routing the call
  5. Minor bugfixes
Name:OZEKI VoIP SIP SDK v10.1.5
Updated: 2014.01.15.
Download:VoIP_SDK-10.1.5.zip  (94.6 MB) 
Changes:
  1. Improvement in speech-to-text
    • Custom speech-to-text engine implementation can be used
    • Word recognition mode can be specified
  2. An improved version of the default demo softphone is included
Name:OZEKI VoIP SIP SDK v10.1.4
Updated: 2013.12.20.
Download:VoIP_SDK-10.1.4.zip  (95.6 MB) 
Changes:
  1. New feature: TLS support in PBX module
  2. Improved compatibility with firewalls and routers
  3. Minor bugfixes
Name:OZEKI VoIP SIP SDK v10.1.3
Updated: 2013.11.13.
Download:VoIP_SDK-10.1.3.zip  (92.3 MB) 
Changes:
  1. Real-time video quality change
  2. Improvement in call media handling
  3. Simplified codec selection
  4. SIP identity can be set on a direct IP phone line
  5. Revised logging system
  6. Minor bugfixes
Name:OZEKI VoIP SIP SDK v10.1.2
Updated: 2013.10.25.
Download:VoIP_SDK-10.1.2.zip  (92.2 MB) 
Changes:
  1. Improved codecs
  2. Improvement in PBX authentication
  3. An improved version of the speaker can be selected
    • Supported OS: Vista and above
  4. Automatic DTMF signalling mode detection during a call
  5. The TextToSpeech MediaHandler can be extended with other TTS engines
  6. Modifications on IPhoneLine interface
    • More information available about the SIP registration at client side (IPhoneLine.RegistrationInfo)
    • RegisteredInfo renamed to LineState
Name:OZEKI VoIP SIP SDK v10.1.1
Updated: 2013.09.16.
Download:VoIP_SDK-10.1.1.zip  (90.3 MB) 
Changes:
  1. Modifications on ICall interface:
    • New property: IsAnswered, indicates whether the call has been answered
    • New method: HoldCall() for putting the call on hold
    • New method: UnholdCall() for taking off the call from hold
    • The older Hold() method has been renamed to ToggleHold()
  2. New CallState has been added: Answered
    • See the sample projects for optimal usage
  3. Improvement in custom SIP/SDP message modification
  4. Improvement in codec selection
  5. The availability of the WebCamera can be checked with the Initialized property
  6. Minor bugfixes
Name:OZEKI VoIP SIP SDK v10.1.0
Updated: 2013.08.21.
Download:VoIP_SDK-10.1.0.429.zip  (90.3 MB) 
Changes:
  1. New feature: Making and receiving P2P calls without SIP server
  2. New feature: Multipart SIP message body support
  3. New feature: Static public IP can be set in NAT configuration
  4. New feature: Handling received blind transfer (REFER) requests at client side
Name:OZEKI VoIP SIP SDK v10.0.11
Updated: 2013.07.24.
Download:VoIP_SDK-10.0.11.zip  (89.6 MB) 
Changes:
  1. Direct IP session setup for VoIP phones
  2. Peer-to-peer SIP session setup
  3. Improvement in transport error management
Name:OZEKI VoIP SIP SDK v10.0.10
Updated: 2013.06.13.
Download:VoIP_SDK-10.0.10.zip  (89.6 MB) 
Changes:
  1. New properties on IPhoneLine interface: LocalAddress, LocalPort
  2. Improvement in PBX call routing
  3. Improvement in PBX messaging
  4. Minor compatibility fixes
Name:OZEKI VoIP SIP SDK v10.0.9
Updated: 2013.03.20.
Download:VoIP_SDK-10.0.9.zip  (89.2 MB) 
Changes:
  1. New feature: video bitrate can be set.
  2. Improvement: it is possible to easily and simply define the type of codecs you wish to use.
  3. PBX improvement: more efficient caller ID and dialed number handling.
  4. Minor bugfixes.
Name:OZEKI VoIP SIP SDK v10.0.7
Updated: 2013.02.01.
Download:VoIP_SDK-10.0.7.271.zip  (86.8 MB) 
Changes:
  1. New feature (New CallState): InactiveHeld. This call state occurs when both parties place the call on hold
  2. Improvement (SIP account): more flexible domain validation during specifying SIP account
  3. Improvement (PBX module): SIP authentication related improvements in the PBX module.
  4. Improvement: optimized Ozeki DemoSoftphone WPF
  5. Minor bugfixes
Name:OZEKI VoIP SIP SDK v10.0.6
Updated: 2012.12.10.
Download:VoIP_SDK-10.0.6.zip  (87.0 MB) 
Changes:
  1. Improvement: TLS authentication has been fixed
  2. Improvement: more stable calls in the PBX module (ISession and CallManager have been changed)
  3. New feature: it is possible to customize speech rate in TextToSpeech
  4. New feature: a MediaHandler that can play unique formats can be derived from AudioStreamPlayback class
  5. New feature: it is possible to select the type of voice that will be played when the maximum number of calls is reached in the PBX module of the licensed Ozeki VoIP SIP SDK
Name:OZEKI VoIP SIP SDK v10.0.5
Updated: 2012.11.07.
Download:VoIP_SDK-10.0.5.zip  (86.7 MB) 
Changes:
  1. Improvement in Redirection (3xx) response handling.
  2. New feature: new CallState (Forwarding) has been added.
  3. Improvement: more stable authentication, registration and calls in PBX module.
  4. Improvement: notification about sent and received SIP messages in PBX module.
Name:Ozeki VoIP SIP SDK v10.0.4
Updated: 2012.09.24.
Download:VoIP_SDK-10.0.4.zip  (86.4 MB) 
Changes:
  1. SIP TCP connection improved
  2. MediaGateway FileNotFoundException fixed
  3. Improved transfer compatibility with Cisco and Avaya
Name:Ozeki VoIP SIP SDK v10.0.3
Updated: 2012.08.23.
Download:VoIP_SDK-10.0.3.zip  (86.3 MB) 
Changes:
  1. New feature: You can send DTMF signal over SIP info.
  2. BUG fix: SIP register compatible with SipXecs PBX.
  3. BUG fix: WP7 packet handling improved.
Name:Ozeki VoIP SIP SDK v10.0.2
Updated: 2012.06.21.
Download:VoIP_SDK-10.0.2.zip  (93.7 MB) 
Changes:
  1. New feature: You can create Windows Phone VoIP application. Many examples included.
  2. New feature: PBX can handle multi-network interface.
  3. Bug: Minor bug fixes in PBX phone calls.
Name:Ozeki VoIP SIP SDK v10.0.1
Updated: 2012.06.12.
Download:VoIP_SDK-10.0.1.zip  (112.1 MB) 
Changes:
  1. New feature: NAT discovery.
  2. Bug fix: microphone instance freezes when microphone device is disconnected.
  3. Reduced installation time.
Name:Ozeki VoIP SIP SDK v10.0.0
Updated: 2012.05.11.
Download:VoIP_SDK-10.0.0.zip  (82.0 MB) 
Changes:
  1. New feature: You can create custom PBX. Many examples included.
  2. Silverlight video stream quality highly improved.
Name:Ozeki VoIP SIP SDK v9.8.0
Updated: 2012.04.27.
Download:VoIP_SDK-9.8.0.zip  (74.4 MB) 
Changes:
  1. Trial time calculation fixed.
  2. SetKeepalive method was removed from ISoftPhone.
  3. VoIP SDK is compatible with voipgateway.org.
Name:Ozeki VoIP SIP SDK v9.7.0
Updated: 2012.04.13.
Download:VoIP_SDK-9.7.0.zip  (74.3 MB) 
Changes:
  1. DTMF event player has changed. You can play dtmf sound anytime(call is not required).
  2. Trial version limitation reduced: You can create unlimited simultaneous phone calls and phone lines.
  3. Incoming calls will not be rejected because of the licensing.
Name:Ozeki VoIP SIP SDK v9.6.0
Updated: 2012.04.02.
Download:VoIP_SDK-9.6.0.zip  (73.9 MB) 
Changes:
  1. New feature: You can add custom phone number, display name in the phone call.
  2. Improvement in LicenseManager.
  3. Improvement in call forwarding.
Name:Ozeki VoIP SIP SDK v9.5.0
Updated: 2012.03.14.
Download:VoIP_SDK-9.5.0.zip  (73.4 MB) 
Changes:
  1. New feature: TLS support.
  2. New feature: attended transfer.
  3. Improvement in Avaya connectivity.
Name:Ozeki VoIP SIP SDK v9.4.0
Updated: 2012.02.24.
Download:VoIP_SDK-9.4.0.zip  (66.6 MB) 
Changes:
  1. New feature: SRTP.
  2. New feature: blind transfer.
  3. New video codec: H.263.
Name:Ozeki VoIP SIP SDK v9.3.0
Updated: 2012.02.10.
Download:VoIP_SDK-9.3.0.zip  (64.8 MB) 
Changes:
  1. New audio codecs:
    • L16
    • G723
    • G726-16
    • G726-24
    • G726-32
    • G726-40
    • G728
  2. Improvement in echo cancellation.
Name:Ozeki VoIP SIP SDK v9.2.0
Updated: 2012.02.02.
Download:VoIP_SDK-9.2.0.zip  (54.2 MB) 
Changes:
  1. Webphone development support (Flash and Silverlight).
  2. Improvement in silence filter.
  3. Minor bug fixes.
Name:Ozeki VoIP SIP SDK v9.1.0
Updated: 2012.01.27.
Download:VoIP_SDK-9.1.0.zip  (41.9 MB) 
Changes:
  1. New feature: Answering machine detection.
  2. Improvement in Voice Activity Detection.
  3. Minor bug fixes.
Name:Ozeki VoIP SIP SDK v9.0.0
Updated: 2012.01.16.
Download:VoIP_SDK-9.0.0.zip  (32.9 MB) 
Changes:
  1. New feature: Video calls are supported effectively from this version.
    Available video codecs:
    • H.263+
    • H.264
Name:Ozeki VoIP SIP SDK v8.9.0
Updated: 2011.11.29.
Download:VoIP_SDK-8.9.0.zip  (15.4 MB) 
Changes:
  1. Improvement in Avaya connectivity.
  2. Improvement in the sample programs.
Name:Ozeki VoIP SIP SDK v8.8.0
Updated: 2011.11.24.
Download:VoIP_SDK-8.8.0.zip  (12.2 MB) 
Changes:
  1. Improvement in registration.
  2. Improvement in microphone handling.
  3. Improvement in the Demo Softphone.
  4. Improvement in JitterBuffer.
  5. Improvement in VoiceIVR sample program.
  6. Improvement in DtmfEventWavePlayer (clearer voice and faster operation).
Name:Ozeki VoIP SIP SDK v8.7.0
Updated: 2011.10.27.
Download:VoIP_SDK-8.7.0.zip  (16.6 MB) 
Changes:
  1. Improvement in TCP/SIP connection.
  2. Bug fix: In some cases the SDK freezes during NAT detection. This bug has been fixed.
Name:Ozeki VoIP SIP SDK v8.6.0
Updated: 2011.10.25.
Download:VoIP_SDK-8.6.0.zip  (16.6 MB) 
Changes:
  1. Improvement in sound quality.
  2. Improvement in the manipulation of SDP messages.
Name:Ozeki VoIP SIP SDK v8.5.0
Updated: 2011.10.07.
Download:VoIP_SDK-8.5.0.zip  (16.6 MB) 
Changes:
  1. Improvement in Skype connectivity regarding receiving calls.
  2. Improvement in stability.
Name:Ozeki VoIP SIP SDK v8.4.0
Updated: 2011.09.23.
Download:VoIP_SDK-8.4.0.zip  (16.5 MB) 
Changes:
  1. Skype connectivity has been further improved.
  2. Improvement in stability.
  3. Improvement in sample programs.
Name:Ozeki VoIP SIP SDK v8.3.0
Updated: 2011.09.13.
Download:VoIP_SDK-8.3.0.zip  (16.5 MB) 
Changes:
  1. Improvement has been made in hang up function for greater efficiency.
  2. Improvement in documentation.
Name:Ozeki VoIP SIP SDK v8.2.2
Updated: 2011.09.08.
Download:VoIP_SDK-8.2.2.zip  (16.5 MB) 
Changes:
  1. This release of Ozeki SIP SDK ensures higher stability in connections.
  2. Improvement has been made in hang up function.
Name:Ozeki VoIP SIP SDK v8.2.1
Updated: 2011.08.26.
Download:VoIP_SDK-8.2.1.zip  (16.2 MB) 
Changes:
  1. Improvement in re-registration.
  2. Improvement in connection stability.
  3. Improvement in memory usage.
Name:Ozeki VoIP SIP SDK v8.2.0
Updated: 2011.08.22.
Download:VoIP_SDK-8.2.0.zip  (16.2 MB) 
Changes:
  1. Improvement in the stability of connection.
  2. Improvement in memory usage. The amount of memory usage is remarkably reduced.
Name:Ozeki VoIP SIP SDK v8.1.1
Updated: 2011.07.21.
Download:VoIP_SDK-8.1.1.zip  (14.6 MB) 
Changes:
  1. Sample programs have been improved for greater efficiency.
  2. Improvement in documentation.
Name:Ozeki VoIP SIP SDK v8.1.0
Updated: 2011.07.15.
Download:VoIP_SDK-8.1.0.zip  (16.1 MB) 
Changes:
  1. Improvement in compatibility with Sipnet.ru.
  2. NAT autodetection.
  3. Improvement in audio file handling.
Name:Ozeki VoIP SIP SDK v8.0.0
Updated: 2011.07.13.
Download:VoIP_SDK-8.0.0.zip  (16.3 MB) 
Changes:
  1. Extended codec support has been added:
    • iLBC
    • G722
    • G729
    • SPEEX
    • GSM
  2. Unified media handling has been added. Meaning that various audio devices can be handled in a unified way.
  3. Totally new audio subsystem has been added to highly improve performance and quality.
  4. Updated sample programs on the various utilization possibilities of the Ozeki SDK.
  5. Improvement in documentation.
  6. Simpler registration.
  7. Simpler usage.
  8. Built-in ring tones, ringback tones, DTMF signals, etc, have been added.
Name:Ozeki VoIP SIP SDK v7.5.1
Updated: 2011.06.27.
Download:VoIP_SDK-7.5.1.zip  (18.2 MB) 
Changes:
  1. Improvement has been made in wav recording.
  2. Improvement in documentation.
Name:Ozeki VoIP SIP SDK v7.5.0
Updated: 2011.06.23.
Download:VoIP_SDK-7.5.0.zip  (18.2 MB) 
Changes:
  1. .NET FRAMEWORK 3.5 is also supported beside .Net Framework 4.0.
  2. This release includes various sample programs with source code (e.g. for creating a softphone, DTMF IVR, IVR voice recognition, etc) to demonstrate the flexibility of Ozeki SIP SDK.
  3. Compatibility with Cisco Unified CM, Freeswitch and Trixbox has been improved.
    Further functions have also been added:
  4. Hold: It ends voice communication (even if the PBX does not handle HOLD function according to the standard).
  5. Packet manipulation: It allows to insert own fields into incoming/outgoing SIP messages, or to modify an existing field.
  6. Redial and Call history have been added to the Demo application.
  7. Handling of Outbound proxy has been added.
  8. Call recording function has been improved.
  9. It is possible to select the audio device to be used.
  10. Volume indicators have been included in the Demo.
Name:Ozeki VoIP SIP SDK v7.4.0.
Updated: 2011.06.03.
Download:VoIP_SDK-7.4.0.zip  (7.0 MB) 
Changes:
    Compatibility with the following PBXs has been highly improved in this version:
  1. FreePBX
  2. Kamailio
  3. OpenSIPS
  4. SIPX
Name:Ozeki VoIP SIP SDK v7.3.0.
Updated: 2011.05.11.
Download:VoIP_SDK-7.3.0.zip  (6.0 MB) 
Changes:
  1. This new release supports STUN protocol to further improve NAT compatibility.
  2. VS2010 ADD-In has been added to be able to use the License Manager in a simpler way.
Name:Ozeki VoIP SIP SDK v7.2.0.
Updated: 2011.04.22.
Download:VoIP_SDK-7.2.0.zip  (5.5 MB) 
Changes:
  1. In this version we include STUN protocol support to further improve NAT compatibility.
  2. This version is also compatible with Asterisk PBX.
Name:Ozeki VoIP SIP SDK v7.1.0.
Updated: 2011.03.17.
Download:VoIP_SDK-7.1.0.zip  (5.4 MB) 
Changes:
  1. In this version of Ozeki VoIP SDK we introduce the basic NAT support for better communication.
  2. Network keepalive mechanism has also been added.
Name:Ozeki VoIP SIP SDK v7.0.0.
Updated: 2011.02.04.
Download:VoIP_SDK-7.0.0.zip  (5.3 MB) 
Changes:
  1. In this new release of Ozeki SIP SDK the whole SIP stack has been redesigned.
  2. This version is based on .Net Framework 4.0.
  3. All example programs have been further improved.
Name:Ozeki VoIP SIP SDK v6.2.0.
Updated: 2010.11.04.
Download:VoIP_SDK-6.2.0.zip  (5.2 MB) 
Changes:
  1. This version of Ozeki VoIP SIP SDK supprots Speex codec for more efficient communciation.
  2. Auto Gain Control functionality has been added.
  3. Accustic echo cancellation feature has also been introduced.
Name:Ozeki VoIP SIP SDK v6.1.0.
Updated: 2010.10.13.
Download:VoIP_SDK-6.1.0.zip  (5.1 MB) 
Changes:
  1. We improved the performance to reduce CPU usage.
  2. Voice Activity Detection functionality has been added.
  3. This version is compatible with 3CX phone system.
Name:Ozeki VoIP SIP SDK v6.0.0.
Updated: 2010.08.12.
Download:VoIP_SDK-6.0.0.zip  (5.0 MB) 
Changes:
  1. DSP (Digital sound processing) functionality has been added to this new release.
  2. NOISE cancellation function has also been added to achieve much better voice quality.
Name:Ozeki VoIP SIP SDK v5.2.0.
Updated: 2010.05.07.
Download:VoIP_SDK-5.2.0.zip  (4.9 MB) 
Changes:
  1. A MOCK softphone has been introduced to help testing.
  2. Mute Sound function has been added.
  3. New example program has been introduced.
Name:Ozeki VoIP SIP SDK v5.1.0.
Updated: 2010.03.06.
Download:VoIP_SDK-5.1.0.zip  (4.8 MB) 
Changes:
  1. New logging sub system has been introduced.
  2. Access SIP messages directly.
  3. SDP update.
Name:Ozeki VoIP SIP SDK v5.0.0.
Updated: 2010.02.23.
Download:VoIP_SDK-5.0.0.zip  (4.7 MB) 
Changes:
  1. New redesigned SIP parser. It is more compatible, reliable and faster than the previous SIP parser.
  2. Improvement: Not all DTMF signals were indicated. This issue has been fixed.
  3. Updated documentation and Help.
Name:Ozeki VoIP SIP SDK v4.2.0.
Updated: 2010.01.08.
Download:VoIP_SDK-4.2.0.zip  (4.6 MB) 
Changes:
  1. IGNORE function has been added.
  2. Forward function has been implemented.
  3. .Software volume control feature has been introduced.
Name:Ozeki VoIP SIP SDK v4.1.0.
Updated: 2009.10.05.
Download:VoIP_SDK-4.1.0.zip  (4.5 MB) 
Changes:
  1. HOLD function has been added.
  2. TRANSFER function has been introduced.
  3. New example program has been added.
Name:Ozeki VoIP SIP SDK v4.0.0.
Updated: 2009.08.24.
Download:VoIP_SDK-4.0.0.zip  (4.4 MB) 
Changes:
  1. The network layer has been redesigned. Therefore the network layer has become faster and more stable.
  2. packet lost concealment feature has been added.
Name:Ozeki VoIP SIP SDK v3.2.0.
Updated: 2009.06.09.
Download:VoIP_SDK-3.2.0.zip  (4.3 MB) 
Changes:
  1. Auto Answer function has been added.
  2. DND function has been introduced.
  3. Support play the wave file to a special line (session).
  4. Support record the conversation on a special line(session).
Name:Ozeki VoIP SIP SDK v3.1.0.
Updated: 2009.04.15.
Download:VoIP_SDK-3.1.0.zip  (4.2 MB) 
Changes:
  1. DTMF as SIP INFO message is supported.
  2. DTMF as specially marked events in the RTP stream is also supported.
  3. Jitter buffer has been added to the RTP. Therefore the voice quality has been improved.
Name:Ozeki VoIP SIP SDK v3.0.0.
Updated: 2009.02.06.
Download:VoIP_SDK-3.0.0.zip  (4.1 MB) 
Changes:
  1. Sound devices are handled efficiently.
  2. Voice can be recorded during conversations in wav format.
  3. More detailed logging has been added.
Name:Ozeki VoIP SIP SDK v2.3.0.
Updated: 2009.01.14.
Download:VoIP_SDK-2.3.0.zip  (4.0 MB) 
Changes:
  1. We introduce manual codec selection in this release. Therefore you can select the codec you wish to use easily according to your needs.
  2. A sample program has been added.
  3. Dynamic codec handling is also supported.
Name:Ozeki VoIP SIP SDK v2.2.0.
Updated: 2008.11.02.
Download:VoIP_SDK-2.2.0.zip  (3.9 MB) 
Changes:
  1. This version supports multiple calls to be made in the same line simultaneously.
  2. Beside multiple calls multiple SIP lines are also handled simultaneously.
Name:Ozeki VoIP SIP SDK v2.1.0.
Updated: 2008.09.10.
Download:VoIP_SDK-2.1.0.zip  (3.8 MB) 
Changes:
  1. This version of Ozeki VoIP SIP SDK supports g711 codec.
  2. GSM codec support is also included for more efficient communication.
Name:Ozeki VoIP SIP SDK v2.0.0.
Updated: 2008.08.07.
Download:VoIP_SDK-2.0.0.zip  (3.7 MB) 
Changes:
  1. This version of Ozeki SIP SDK also supports RTP beside SIP. In this way voice calls can be established more efficiently.
  2. The registration in the PBX has been further improved. Previously the SDK does not always register in the PBX. This issue has been fixed.
Name:Ozeki VoIP SIP SDK v1.2.0.
Updated: 2008.05.16.
Download:VoIP_SDK-1.2.0.zip  (3.6 MB) 
Changes:
  1. Now the system is able to register in the PBX succssfully.
  2. A more detailed documentation has been added to the SDK to help more efficient handling.
Name:Ozeki VoIP SIP SDK v1.1.0.
Updated: 2008.04.05.
Download:VoIP_SDK-1.1.0.zip  (3.6 MB) 
Changes:
  1. Logging function has been added to the SDK to achieve more efficient debugging.
  2. A major improvement in ATA handling has been introduced.
Name:Ozeki VoIP SIP SDK v1.0.0.
Updated: 2008.02.17.
Download:VoIP_SDK-1.0.0.zip  (3.5 MB) 
Changes:
  1. We are proud to announce that the first official release of Ozeki SIP SDK is available. This component supports SIP protocol effectively and allows to create a C# softphone or a VB.Net softphone in minutes in any software developed in .Net.