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Marconi's SMA1/4UC, multiservice metro platform provides outstanding capacity and flexibility in an ultra-compact shelf and is optimized for 63 x 2Mbit/s. Evolutions of this platform includes an extended shelf for increased 2 mbit/s capacity (SMA1/4EX) and an STM-16 variant(SMA16UC and SMA16EX). Marconi's Series 4 SMA is a comprehensive range of optimised STM1/4 multiplexers suitable for smaller metro networks where higher port densities are required. The implementation of PacketSpan technology brings Next-Generation SDH functionality (GFP, LCAS and VCAT) to these and previous generations of Marconi's SMA & MSH multiplexers via a range of simple, plug-in cards.