This amendment provides the G.992.1 revision (revision of Annex C, addition of Annex I and addition of Appendix V). It includes the changes introduced by G.992.1 (1999) Corrigendum 2. Revised Annex C covers specific requirements for an ADSL system operating in the same cable as ISDN as defined in Appendix III/G.961. Annex I covers ADSL system with improved performance on short loops operating in the same cable as TCM-ISDN as defined in Appendix III/G.961. Appendix V contains some example overlapped PSD Masks for use in a TCM-ISDN crosstalk environment.