How OSPrey Works
How OSPrey Works
OSPrey as a Route Server (VoIP SCP)
OSPrey may be configured as a route server and CDR collection server for a VoIP signaling device such as a softswitch, gatekeeper, SIP proxy or session border controller. In this type of deployment, the OSPrey server provides the intelligence and scale for routing features that cannot be provided by a VoIP signaling device. For example, since many VoIP signaling devices cannot support a large least cost routing table, this function is off-loaded to the OSPrey server which can support a routing table with 50,000,000+ destinations. An example call scenario for this type of deployment is described below. A single VoIP Switch is shown in the diagram, but typically multiple VoIP signaling platforms of different types could are served in parallel by one or more OSPrey servers sharing the load.
- A call originates from the Source VoIP Device and is routed to the VoIP Switch.
- The VoIP Switch sends a routing query to the OSPrey server. The OSPrey performs a route lookup and returns a list of IP addresses of devices which can complete the call to the called number. The OSPrey can translate the calling or called number as needed.
- The call is routed from the VoIP Switch to the Destination VoIP Device which completes the call.
- At the end of the call, the VoIP Switch sends a call detail record to the OSPrey server.
OSPrey as a Secure Peering Server
The OSPrey server may also be used as a secure peering server for authorizing and accounting for direct peer to peer communications between anonymous VoIP networks. For direct peering, each VoIP peer must enroll with the OSPrey certificate authority to obtain the OSPrey server’s public key. Also, the OSPrey server signs the certificate request from each VoIP device. The call scenario in the diagram below illustrates the OSPrey server being used as a peering server.
- A VoIP call originates from the Source VoIP Device.
- The Source VoIP Device sends a route query to the OSPrey server which returns a list of IP addresses of devices which can terminate the call. Included with each address is a digitally signed peering token authorizing the call.
- The Source VoIP Device sends a SIP Invite or Q.931 call setup message directly to the destination peer. The peering token is included in the SIP Invite or Q.931 call setup message.
- When the call is finished, both the source and destination devices send call detail records to the OSPrey server.