The basic SONET Frame structure is known as STS-1
or Sychronous
Transport Signal
level 1.
It has a basic frame rate of 8,000 frames/sec = 51.84Mb/s.
The frame length is 9-rows by 90-columns of octets - total frame size 810
octets. The first three columns are transport overhead, while columns
4-90 are the SPE -
Synchronous Payload
Envelope with
actual transport speed of 50.112Mb/s.