Erlanger Health System\u2019s goal was to bring together its voice and data networks, modernize the data network, reduce costs, reduce complexity, and improve patient services. We recently had a chance to talk with John Haltom, Erlanger\u2019s network director, about his progress with convergence.Erlanger, a nonprofit organization owned by the Chattanooga-Hamilton County Hospital Authority, offers a diverse scope of health services, including a children's hospital, a cancer treatment facility, heart surgery centers, organ transplants, burn treatment, eye care, and women's health. The system also runs its own ambulance and air-flight EMS services. The system includes 10 major locations with over 900 physicians.One of the challenges Erlanger faced was bringing together a multi-vendor PBX environment as it made the transition to VoIP; the organization had to continue to support PBXs supplied from Lucent (now Avaya) and from Nortel. And it didn\u2019t want to make a total shift to VoIP. Rather, Erlanger elected to replace some parts of its voice network with VoIP and leave other parts alone. The decisions on upgrades were, according to Haltom, made on business needs, including a detailed ROI analysis.Erlanger selected Nortel\u2019s Succession portfolio for VoIP. By making the move to Succession, it was able to keep its multi-vendor PBX environment and make a graceful transition to VoIP telephony where it made sense.Haltom has a few key suggestions for others. First, he says, \u201cMake sure you complete a full data network assessment. It\u2019s amazing how forgiving Ethernet is in a pure data environment. But making voice work on the data network isn\u2019t automatic.\u201dSecond, he found that two features didn\u2019t work between the two vendors\u2019 systems. The caller ID and the voice-mail-generated message-waiting indicators were incompatible between the two voice mail systems. (Note: Voice mail message indicator compatibility can also be an issue in a multi-vendor TDM environment as well.)To fix the problem, Erlanger would have had to make major upgrades to the Lucent PBX that included a new software load with QSIG-based signaling. Haltom said the ROI just didn\u2019t prove out, so if the missing features became a must for a user, he would upgrade their service to a VoIP phone based on the Succession platform.Finally, he noted that a planned, phased migration worked well.Next time, we\u2019ll look at how Erlanger improved patient service by including wireless Ethernet.