A method for adapting a digital subscriber line, DSL communications duplexing scheme to meet user application needs, comprising - determining, for a new DSL loop communication, a required upstream bit rate and a required downstream bit rate for the user application wherein said determining comprises removing idle ATM cells and said required upstream bit rate and said required downstream bit rate are determined without the inclusion of said idle ATM cells; - dividing the required upstream bit rate by the required downstream bit rate to obtain a desired duplexing ratio for the new DSL communication, the duplexing ratio being the ratio between upstream and downstream bandwidth used on the DSL loop to carry data communications; and - adapting a duplexing scheme implemented by a DSL modem in support of the new DSL loop communication to at least approximate the desired duplexing ratio, wherein the required upstream bit rate of the new DSL loop communication corresponds to a required upstream bandwidth that is smaller than a total available upstream bandwidth, the method further comprising the steps of: - calculating, for a plurality of location positions of the required upstream bandwidth for the new DSL loop communication within the corresponding total available upstream bandwidth, a crosstalk noise effect with respect to other active DSL loops (22, 24, 26) in a same cable bundle; and - choosing a location position for the required upstream bandwidth to carry the new DSL loop communication within the total available upstream bandwidth where the calculated crosstalk noise effect with respect to any other active DSL loops (22, 24, 26) is minimized. - determining, for a new DSL loop communication, a required upstream bit rate and a required downstream bit rate for the user application wherein said determining comprises removing idle ATM cells and said required upstream bit rate and said required downstream bit rate are determined without the inclusion of said idle ATM cells; - dividing the required upstream bit rate by the required downstream bit rate to obtain a desired duplexing ratio for the new DSL communication, the duplexing ratio being the ratio between upstream and downstream bandwidth used on the DSL loop to carry data communications; and - adapting a duplexing scheme implemented by a DSL modem in support of the new DSL loop communication to at least approximate the desired duplexing ratio, wherein the required upstream bit rate of the new DSL loop communication corresponds to a required upstream bandwidth that is smaller than a total available upstream bandwidth, the method further comprising the steps of: - calculating, for a plurality of location positions of the required upstream bandwidth for the new DSL loop communication within the corresponding total available upstream bandwidth, a crosstalk noise effect with respect to other active DSL loops (22, 24, 26) in a same cable bundle; and - choosing a location position for the required upstream bandwidth to carry the new DSL loop communication within the total available upstream bandwidth where the calculated crosstalk noise effect with respect to any other active DSL loops (22, 24, 26) is minimized. - calculating, for a plurality of location positions of the required upstream bandwidth for the new DSL loop communication within the corresponding total available upstream bandwidth, a crosstalk noise effect with respect to other active DSL loops (22, 24, 26) in a same cable bundle; and - choosing a location position for the required upstream bandwidth to carry the new DSL loop communication within the total available upstream bandwidth where the calculated crosstalk noise effect with respect to any other active DSL loops (22, 24, 26) is minimized.