Huawei Technologies Huawei Technologies Verizon Communications Inc. TThe dynamic allocation of computing resources on a massive scale through the use of virtual machines to serve a large number of customers and applications simultaneously brings a number of benefits but also a number of challenges to data center operations. Such challenges range from acquiring the information needed to provision the physical servers, storage and networking elements, through accounting for resource and application usage at the user level. In particular, this document describes the problem of operational and management challenges that virtualization brings in the (carrier) data center as an enabler of new technologies such as self- provisioning and elastic capacity and related benefits of consolidation, reduced total cost of ownership, and energy management. This document does not cover the problem of address resolution in massive data centers. It does not cover technologies related to VDI either.