how many vc4 in stm 1?
The STM-1 MUX multiplexes 63 E1 signals into a STM-1 stream, with TU-12 cross-connect capability. As a standard and compact SDH TDM device, the STM-1 multiplexer is best suited to applications where high-density E1 ports are required to interface with an SDH network through STM-1 fiber optic connections.