The virtualized workloads, cloud applications, and big data services today are driving previously server and data center fabric to an unimagined level. The existing 1Gbqs or 10Gbqs are gradually overwhelmed by higher-bandwidth like 40Gbps or 100Gbqs. Thus high-capacity optical technology and cabling infrastructure are required to support those servers and applications for 40Gbps upgrading. However, it might be too costly to replace all your equipment for 40G transition. So this article will introduce a cost-saving solution to help you smoothly migrate to 40GbE with the use of 40G BiDi QSFP+ transceiver.