By ADSL (Asymmetric Digital Subscriber Line) technology

high speed access INTERNET can be realized through twisted copper pair lines which are already used in PSTN (public switch telephone network) to connect telephone users.ADSL becomes a focused point in area of access network.The paper describes ADSL DSLAM (Digital Subscribe Loop Access Multiplexer) architectures and how to design and realize them.It analyses the transmission efficiency of these DSLAM and gets the result that the ADSL DSLAM with IP direct connection is more efficient.It discusses in detail the realization of ADSL DSLAM with IP direct connection architecture.The solutions to some key problems are given.