Today, we like to recommend two excellent white papers for readers who want to consider the move from legacy TDM telephony to SIP-based communication systems. Both papers are authored by Cisco, but provide some great generic tips for the enterprise to consider.

The first paper, “Integrating SIP Trunks in Enterprise Networks for Next-Generation Unified Communications” discusses the evolution and adoption of unified communications trunking services in the enterprise. The second white paper, “Implementation Considerations when Enhancing Enterprise Communications Solutions with SIP Trunks,” provides a more detailed technical analysis of the issues.

The first paper briefly describes the business advantages and challenges of unified communications trunking and the network considerations for adoption. Important to the transition from TDM trunks to unified communications SIP trunks is the need to maintain all of the benefits associated with TDM interfaces while exploiting the efficiencies of extending unified communications. The paper covers the business advantages of SIP trunking for unified communications, and it looks at the major network deployment issues such as the demarcation point, Call Admission Control (CAC), voice call routing, security, interoperability and a graceful migration.

The second white paper provides a more detailed technical analysis of issues such as selecting a distributed model vs. a centralized model, quality of service implications, protocol and media Interworking, unified communications IP endpoints, supplementary services, emergency calling, billing, and troubleshooting tools and methods. It concludes that the transition to SIP is a significant network change that should be done with the appropriate planning and may require several phases of deployment.

Next time, we hear from Jim Metzler, vice president of Ashton, Metzler & Associates, and co-author of Network World’s Wide Area Networking newsletter about effective VoIP management.

Steve Taylor is president of Distributed Networking Associates and publisher/editor-in-chief of Webtorials. Larry Hettick is a principal analyst at Current Analysis.