CONTENTS

         H.1     Scope
        H.2     Definitions
        H.3     Reference Models
                  H.3.1     System reference model
                  H.3.2     ATU‑C transmitter reference model (replaces figures in 5.1)
                  H.3.3    ATU‑R transmitter reference model (replaces figures in 5.2)
                  H.3.4     ATU‑C/R transmitter timing model (replacement for 5.3)
        H.4     Transport capacity (supplements clause 6)
                  H.4.1     Transport of STM data (supplements 6.1)
                  H.4.2     Transport of ATM data (supplements 6.2)
        H.5     ATU‑C functional characteristics (supplements clause 7)
                  H.5.1     STM transmission protocol specific functionality (pertains to 7.1)
                  H.5.2     ATM transmission protocol specific functionalities (pertains to 7.2)
                  H.5.3     Framing (pertains to 7.4)
                  H.5.4     Bitmapping and rate conversion (replaces 7.15)
                  H.5.5     Modulation (pertains to 7.11)
                  H.5.6     ATU‑C downstream transmit spectral mask (replaces 7.14)
        H.6     ATU‑R functional characteristics (supplements clause 8)
                  H.6.1     STM transmission protocols specific functionalities (pertains to 8.1)
                  H.6.2     ATM transmission protocols specific functionalities (pertains to 8.2)
                  H.6.3     Framing (pertains to 8.4)
                  H.6.4     Bitmapping and rate conversion (replaces 8.15)
                  H.6.5     Modulation (pertains to 8.11)
                  H.6.6     ATU‑R upstream transmit spectral mask (supplements 8.14)
        H.7     EOC operations and maintenance (pertains to clause 9)
                  H.7.1     ADSL line related primitives (supplements 9.3.1)
                  H.7.2     Test Parameters (supplements 9.5)
        H.8     Initialization
                  H.8.1     Initialization with hyperframe (replaces 10.1.5)
                  H.8.2     Handshake – ATU-C (supplements 10.2)
                  H.8.3     Handshake – ATU-R (supplements 10.3)
                  H.8.4     Transceiver training – ATU‑C (supplements 10.4)
                  H.8.5     Transceiver training – ATU‑R (supplements 10.5)
                  H.8.6     Channel analysis (ATU‑C) (supplements 10.6)
                  H.8.7     Channel analysis (ATU‑R) (supplements 10.7)
                  H.8.8     Exchange – ATU‑C (supplements 10.8)
                  H.8.9     Exchange – ATU‑R (supplements 10.9)
        H.9     AOC on-line adaptation and reconfiguration (pertains to clause 11)
                  H.9.1     Bit swap acknowledge (supplements 11.2.5)
       H.10     Electrical characteristic (new)
                 H.10.1     L1-to-L2 capacitance (new)