The study on Profibus-DP communication network of profibus field bus is mainly concentrated on the establishment of complete communication network from master station to slave ones.Taking the station nodes in redundant technology and the communication line as the objects of study

two kinds of standby master station

namely non-working and working ones

have been presented

and the working standby master station being divided into two sorts

e.i.the basic type of rapid redundance and the improved type of rapid redundance

adding the redundant type of working standby master station system

there are three modes of realization for Profibus-DP communication network

and the advantages and disadvantages of them being compared.The station nodes of basic type rapid redundance is redundant

the communication line isn't redundant

the improved type of rapid redundant system remedies the short comings of non-redundance in the communication network of basic type station in rapid redundance.