fairly arbitrary size (e.g., 100 Mbps) without the need intermediate network elements to support this particular form of concatenation. VCAT is an inverse multiplexing technique, defined by ITU-TRecommendations G.707 and G.783. VCAT enables efficient SONET/SDH SONET/SDH WDM Optical Network Physical Fiber Plant Figure 7.12 Optical inter-working framework. Reproduced with permission from C Telcordia Technologies Inc. [18] Transmission Networks Ethernet NGSDH Fiber Figure 7.13 MSPP functions. Reproduced with permission from C 2009 Ericsson [19] mapping of Ethernet frames directly to the data space of SDH containers, which is also known as a Virtual Concatenation Group. Link Capacity Adjustment Scheme (LCAS) allows for dynamically changing the bandwidth via dynamic virtual concatenation, multiplexing containers based on the short-term bandwidth needs in the network. It can be considered as Virtual Concatenation upgraded with a control mechanism, which enables it to adjust the transfer capacity of the virtual channel. LCAS is a method of dynamic adjustment and reconfiguration of the SDH channels in accordance with ITU-T Recommendation G.7042. Generic Framing Procedure (GFP) is a multiplexing technique defined by ITU-T G.7041 that allows mapping of variable length, higher-layer client signals over a transport network like SDH/SONET. 7.4.1.6 MSPP MSPP (Multi Service Provisioning Platform) results from the combination of NG-SDH with Ethernet switching and aggregation. MSPP can also have WDM and MPLS features as well, as shown in Figure 7.13. MSPPs can have other names, such as multi-service transport platform (MSTP) which appeared from 2002 to provide Ethernet switching and aggregation alongside TDM capability. MSPP also enables the phased transition where the shift to Ethernet is handled customer by customer basis to maximize the utilization of existing assets. The MSPP name is often associated with most ports being in TDM format, but some recent MSPPs can have 100% Ethernet ports. Typically MSPPs are used at the first 