Managing inter-datacenter (DC) connectivity to transport increasing amounts of data and optimize DC performance and costs becomes a challenge not only for DC operators but also for network operators. Current inter-DC connections are configured as static big fat pipes, resulting in large bitrate over-provisioning thus increasing operational costs for DC operators. Furthermore, because of the nature of inter-DC traffic, which highly varies during the time, network operators cannot share such connections with other customers, and network resources may be underutilized. Therefore, an increasing number of studies are being carried out with the aim to address different challenges arising from inter-DC connectivity requirements. This paper summarizes connectivity models and results showing remarkable advantages of considering carrier software defined network (SDN) and elastic operations for managing inter-DC connections. © 2014 IEEE.