This research aims to study the effects of weaknesses on the performance of the existing network such as the impact of Attenuation and crosstalk on the data transfer, and it presents also the improvements of the standards of DSL systems to achieve the maximum transition rates in order to have greater speed in the installation of high-speed subscriber lines. It also offers a new range of services to communication companies through the provision of new xDSL technologies in the near future. Thus, it enables its customers access to broadband services and provides tips for the Syrian Telecommunications Company in their choice of systems. This research analyses the essence of the techniques and the strengths and weaknesses of the criteria for All Digital Mode digital subscriber line mentioned in Annex A and for higher upstream digital subscriber line mentioned in Annex M. It also includes an analytical study of the damping and crosstalk to show how to consider any criteria as a better choice. Finally, It includes programmatically represented simulation of the signal which is sent over transmission lines under the influence of the studied factors.