The xTU Transmission System (XTS) in use. This parameter may be derived from the handshaking procedures defined in Recommendation G.994.1. The invalid value is 4294967295. If data on the port is invalid or no data is generated on the port because the port has not been activated, the invalid value will be returned. One of XDSL line transmission modes: ANSI_T1413(1) ETSI_DTS_TM06006(2) G9921_POTS_NONOVERLAP(3) G9921_POTS_OVERLAP(4) G9921_ISDN_NONOVERLAP(5) G9921_ISDN_OVERLAP(6) G9921_TCMISDN_NONOVERLAP(7) G9921_TCMISDN_OVERLAP(8) G9922_POTS_NONOVERLAP(9) G9922_POTS_OVERLAP(10) G9922_TCMISDN_NONOVERLAP(11) G9922_TCMISDN_OVERLAP(12) G9921_TCMISDN_SYMMETRIC(13) G9923_POTS_NONOVERLAP(19) G9923_POTS_OVERLAP(20) G9923_ISDN_NONOVERLAP(21) G9923_ISDN_OVERLAP(22) G9924_POTS_NONOVERLAP(25) G9924_POTS_OVERLAP(26) G9923_ANNEXI_ALLDIGI_NONOVERLAP(29) G9923_ANNEXI_ALLDIGI_OVERLAP(30) G9923_ANNEXJ_ALLDIGI_NONOVERLAP(31) G9923_ANNEXJ_ALLDIGI_OVERLAP(32) G9924_ANNEXI_ALLDIGI_NONOVERLAP(33) G9924_ANNEXI_ALLDIGI_OVERLAP(34) G9923_ANNEXL_POTS_NONOVERLAP_MODE1_WIDEUS(35) G9923_ANNEXL_POTS_NONOVERLAP_MODE2_NARROWUS(36) G9923_ANNEXL_POTS_OVERLAP_MODE3_WIDEUS(37) G9923_ANNEXL_POTS_NONOVERLAP_MODE4_NARROWUS(38) G9923_ANNEXM_POTS_NONOVERLAP(39) G9923_ANNEXM_POTS_OVERLAP(40) G9925_POTS_NONOVERLAP(41) G9925_POTS_OVERLAP(42) G9925_ISDN_NONOVERLAP(43) G9925_ISDN_OVERLAP(44) G9925_ANNEXI_ALLDIGI_NONOVERLAP(47) G9925_ANNEXI_ALLDIGI_OVERLAP(48) G9925_ANNEXJ_ALLDIGI_NONOVERLAP(49) G9925_ANNEXJ_ALLDIGI_OVERLAP(50) G9925_ANNEXM_POTS_NONOVERLAP(51) G9925_ANNEXM_POTS_OVERLAP(52) G9931(65) G9932_ANNEXA_POTS(73) G9932_ANNEXA_ISDN(74) G9932_ANNEXB_POTS(75) G9932_ANNEXB_ISDN(76) G9932_ANNEXC_POTS(77) G9932_ANNEXC_ISDN(78) G9935(79) G9935_FRIENDLY_DS(80) G9935_FULL_FRIENDLY(81) G9701(82)