OneContact SIP Cloud - OneSIPConnector

OneSIPConnect that performs Session Border Controller (SBC) role, solving NAT traversal issues between sip endpoints (softphones and media servers) located in client network and the server.



  • Security
    • DoS attack - reject calls when the system is overloading
    • Malformed packet protection
    • Encryption of signaling via TLS
    • Authentication, authorization, and accounting (AAA)
  • Interoperability
    • NAT traversal
    • Session Routing
    • SIP Headers Manipulation - copy headers
    • IPv4 and IPv6 support
    • Transport interworking (TCP, UDP)
      • TCP in external interface is translated to UDP in internal one.
      • Receives in UDP and sends in UDP
    • WebRTC capabilities
    • QoS
      • TOS/DSCO bit setting
      • Resource allocation – OneSIPConnector has a configured limit and reject calls if the number of RTP streams passes the limit
      • Control the Rate limit
      • Media Release (Anti-tromboning)
    • Media Services
      • Support for voice, video and IM calls


Relations to other modules

  • OneSIPConnector acts as a B2B UA standing between the server network and the internet.
  • All SIP and RTP communication pass through OneSIPConnector – RTP may be release depending in the UA NAT type.
  • OneSIPConnector uses the SIPConnector Database to retrieve configurations and store location information.





Performance & Scalability

  • OneSIPConnector scales horizontally by adding more machines to a load balancing SIP farm. The SIP REGISTER goes through the load balancer; all subsequent messages to a specific destination go directly to the physical node that received the REGISTER.
  • When scaling the system horizontally it’s useful to split the load accordingly with the UA location, clustering together in the same node those who have the possibility of establishing a direct RTP stream (media release).
  • The OneSIPConnector CPU usage is affected by the number of SIP messages and RTP streams handled. If OneSIPConnector is unable to perform the media release, it has to process the RTP streams. The OneSIPConnector CPU usage is also affected by the number of endpoints using WebRTC. WebRTC consumes mpre CPU than SIP.
  • The OneSIPConnector memory usage is affected by the number of simultaneous calls and registered extensions.



N+1 redundancy or failover cluster.



  • OneSIPConnector can be deployed in Intel x64 or AMD machines running Windows Server 2016.
  • OneSIPConnector is deployed as a windows service.