White Paper Abstract:
Cisco recommends an alternative architecture called IP over DWDM, which eliminates the need for optical to electrical to optical (OEO) conversion equipment between the router and the optical layer (including both transponders and SONET gear) by combining DWDM router interfaces with an optically switched DWDM layer. This streamlined core architecture improves the flexibility, power efficiency, and reliability of the core network, while providing significant operating and capital cost savings.
The main question when considering this alternative architecture is this: Does IP over DWDM provide significant enough benefits to make this change worthwhile? This document compares the IP-over-DWDM approach with conventional approaches to core networks and presents detailed, quantitative research demonstrating the advantages of this architecture.