Having a DCS in a circuit-switched network provides important flexibility that can otherwise only be obtained at higher cost using manual "DSX" cross-connect patch panels.
Transmuxing changes the “container” without changing the “contents.” Transmuxing provides the carrier the capability to embed a telecommunications signal from one logical TDM circuit to another within SONET without physically breaking down the TDM circuit into its components and reconstructing it.
This is typically done to minimize the number of connections and circuits needed to optimize the total cost.
Common signals connecting to a DCS are at the Electrical - DS1, DS3 levels and Optical (OCx) - OC3, OC12, OC48, and OC192.
The DCS must be able to groom the traffic, economically and quickly, at the most efficient and desired levels.
In those I/O shelves, the signals are prepared to be sent to the central Matrix shelf as VT mapped STSs.