A SONET framed port—as well as an SDH framed port—can be divided into three STS1 paths. Each SONET port can be subdivided further into lower-speed virtual tributaries (VTs). Similarly, each SDH port can be subdivided into lower-speed virtual containers (VCs). As stated in OC3 Channelization using SONET and SDH, the CLI uses SONET STS1/VT configuration conventions to configure SDH VC paths.
The following examples illustrate the use of SONET CLI terminology to configure SDH paths. See the STS1 branch under SDH framing in Figure: OC3 Channelization using SONET and SDH.