From Serebra Learning Corporation
High Speed Technologies Part 4 - Frame Relay 
This is the fourth course in a five part series that covers the history of frame relay frame relay mode protocol architecture and call control. This course also covers
LAPF congestion in frame relay networks approaches to congestion control traffic rate management explicit congestion avoidance and implicit congestion control.
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High Speed Technologies Part 5 - SONET/SDH 
This is the last course of a five part series that students will learn about optical transmission multiplexing optical networks synchronous optical network (
SONET) signals SONET frames. Additionally students will learn about overheads pointers virtual tributaries SONET networks synchronous digital hierarchy (
SDH) SONET and SDH hierarchies.
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