tion and the WDM technique, and from another side on the availability of optical nodes (ROADM) and photonic cross-connects (PXC). Thus [14]: A first approach is to increase the number of optical channels in a WDM system. Based on ITU-T recommendations, commercial DWDM terrestrial systems with a capacity of 1.6 Tbps (160 optical channels at 10 Gbps) on an optical fiber pair are now available with a channel spacing of 25 GHz. Next Generation Mobile Communications Ecosystem A second evolution is in the direction of reducing the number of OEO conversions and migration towards all-optical-network (AON). ITU-T Recommendation G.696.1 provides physical layer spec- ifications for DWDM optical networking applications with line amplifiers that may cover distances of more than 1000 km. AON is expected to cover all potential routes of the backbone network with optical paths up to around 2000 km. Lastly, Ethernetis evolving to move from the backbone part of the transport network towards metro networks via Carrier Ethernet technologies. Most traditional implementation of Ethernet services actually uses Ethernet over MPLS due to their superior carrier-grade characteristics and ability to reuse existing infrastructure. However, PBB-TE doesn't rely on MPLS and can provide a true carrier-grade pure Ethernet transport solution. MPLS-TP rely on MPLS-based techniques to implement control plane functionality featuring scalability, reliability, service management, quality of service, and support for legacy TDM services. The integration of IP/MPLS and MPLS-TP will be dominant in the next decade. Industry Outlook Today, the vast majority of base stations only support TDM and ATM modes of transportation. 3GPP Node Bs are on the horizon that also have Ethernet ports to carry IP traffic. The Mobile WiMAX base stations and upcoming E-UTRAN eNBs only have Ethernet ports. Carrier Ethernet technologies are looking to replace SONET in the long run while IP/MPLS is already present in the backbone network. Thus, the transport network is gradually t