Optical systems and networks are important infrastructures to support information society.In the Big Data era

the emerging applications such as cloud computing

mobile interconnection

and virtual reality demand an ever-increasing capacity of information transportation.To meet this requirement

optical fiber transmission technology keeps the developing towards highspeed and large capacity.In this paper

we introduce the main recent advances in high-speed optical fiber transmission and discuss some enabling technologies of coherent detection for long haul transmission and direct detection for medium and short distance transmission.Some new technologies are summarized and a perspective is presented for high baud rate optical fiber transmission.