SEaMLESS: a SErvice migration cLoud architecture for energy saving and memory releaSing capabilities.

Idle virtual machines (VMs) are a waste of resources in data centers. We introduce SEaMLESS, which transforms a fully-Hedged idle VM into a lightweight and resourceless Virtual Network Function (VNF). Idle VMs can then be saved to disk and release their memory. Simultaneously, the VNF provides service availability. Upon user activity, the appropriate VM is restored, without introducing any interruption for service users. Tens of VNFs can be contained within the same memory space required for one single VM, thereby facilitating ample resources savings when scaled up to a data center.