The ST-1000 and ST-20 scalable switching and transport nodes are capable of
up to 77.5 Mbps full-duplex operation. The ST-1000 is available in multiple-shelf
configurations (one to four shelves) and the ST-20 is available in a single-shelf
configuration. Both versions efficiently handle time division multiplexed (TDM)
transmissions and packet (Frame Relay) transmissions by dynamically allocating
bandwidth based on traffic volume. In addition, the ST-1000 accepts the
internetworking modules, which allow an ST node to directly connect to local area
An ST network can support up to 255 nodes. Trunks between ST nodes, called
internodal links (INLs), connect through T1M, E1M, E3M, BRM, or SDM modules.
Each node can connect up to 31 INLs.
The INLs support satellite buffering and Key Generator Resynchronization.
Synchrony ST Key Features
-- One key feature of ST is the integration of TDM constant bit rate (CBR) and variable
bit rate (VBR) traffic, which is realized through a hybrid switch engine.
-- The Express Switching infrastructure of the ST platform provides the capability to
merge TDM transmissions and packet transmissions natively onto one transmission
facility. Express Switching architecture combines:
- Circuit switching technology, which supports CBR traffic such as PCM voice, compressed
voice, video, and high duty-cycle data traffic like FEP to FEP.
- Frame relay switching technology, which supports VBR traffic such as legacy and LAN.
- Results in a very low end-to-end delay.
-- Express Switching architecture dynamically allocates bandwidth on the INL in real
time. Circuit bandwidth is only used when required. At all other times, the bandwidth
is made available to the frame traffic in order to increase the effective transfer rate to
- Intelligent voice switching and compression
- Key Generator (KG) Resynchronization