The difference in references. I,m no reading them now too busy.
[ITU-T G.993.1] Recommendation ITU-T G.993.1 (2004), Very high speed digital
subscriber line transceivers (VDSL).
[ITU-T O.42] Recommendation ITU-T O.42 (1988), Equipment to measure non-
linear distortion using the 4-tone intermodulation method.
[
IEEE 802.3] IEEE 802.3-2005, IEEE Standard for Information technology
Telecommunications and information exchange between systems
Local and metropolitan area networks Specific requirements Part
3: Carrier Sense Multiple Access with Collision Detection
(CSMA/CD) Access Method and Physical Layer Specifications.
[ISO 8601] ISO 8601:2004, Data elements and interchange formats
Information interchange Representation of dates and times.
[ANSI T1.TRQ.10] ANSI T1.TRQ.10-2003, Splitters used for Line Splitting and Line
Sharing Applications.
[ATIS-0600016] ATIS-0600016.2008, Remote End POTS Splitter Requirements.
[Broadband Forum TR-048] Broadband Forum TR-048 (2002), ADSL Interoperability Test Plan.
[ETSI TS 101 388] ETSI TS 101 388 V1.4.1 (2007), Access Terminals Transmission and
Multiplexing (ATTM); Access transmission systems on metallic access
cables; Asymmetric Digital Subscriber Line (ADSL) European
specific requirements [ITU-T Recommendation G.992.1 modified].
[ETSI TS 101 952-1] ETSI TS 101 952-1 V1.1.1 (2002), Access network xDSL
transmission filters; Part 1: ADSL splitters for European deployment.
[ETSI TS 102 080] ETSI TS 102 080 V1.4.1 (2003), Transmission and Multiplexing
(TM); Integrated Services Digital Network (ISDN) basic rate access;
Digital transmission on metallic local lines.