Evariste Systems is an Atlanta-based software company specialising in open source-focused VoIP service delivery engineering for Internet Telephony Service Providers (ITSPs) and carriers. Our primary line of trade is our SIP trunking delivery system, the Canonical SIP Routing Platform (CSRP). This product solves many technical and business problems in the delivery of "Class 4"-style SIP trunking services, including high-performance Least Cost Routing (LCR), flexible call routing, and on-the-fly call accounting and rating.