scope:

This Recommendation specifies the transmission convergence layer of 40 Gigabit-capable passive optical network (NG-PON2) systems providing optical access for residential, business, mobile backhaul, and other applications.

This Recommendation specifies:

- the supported nominal line rate combinations and the layered structure of the NG-PON2 time and wavelength division multiplexing subsystem transmission convergence (TWDM TC) layer;

- functionality of the TWDM TC service adaptation sublayer, including the use of 10-Gigabit passive optical network (XG-PON) encapsulation method (XGEM), XGEM frame delineation and service data unit (SDU) fragmentation;

- functionality of the TWDM TC framing sublayer with the specification of the downstream frame and upstream burst formats;

- functionality of the TWDM TC physical interface (PHY) adaptation sublayer, including synchronization, forward error correction and scrambling;

- TWDM PON embedded management functionality, including upstream time-division multiple access and dynamic bandwidth assignment mechanisms;

- the NG-PON2 physical layer operation, administration and management (PLOAM) messaging channel;

- the optical network unit (ONU) activation cycle state machine, covering activation and wavelength channel handover;

- timing aspects of TWDM PON point-to-multipoint operation and time-of-day communication;

- TWDM performance monitoring, supervision, and defects;

- TWDM security including cryptographic mechanisms for authentication, integrity verification, channel isolation and data protection along with the associated key exchange protocols;

- signalling mechanisms and protocols to support ONU power management;

- TWDM wavelength channel management;

- TWDM system protection;

- alien device and rogue ONU behaviour mitigation;

- contention-based operation of NG-PON2 system;

- the layered structure of the NG-PON2 PtP WDM subsystem auxiliary management and control channel transmission convergence (AMCC TC) layer;

- AMCC TC layer functionality for transparent mode;

- AMCC TC layer functionality for transcoded mode;

- functionality of the AMCC TC management service adaptation sublayer;

- functionality of the AMCC TC framing sublayer;

- functionality of the AMCC TC PHY adaptation sublayer;

- functionality of the PtP WDM management framing sublayer;

- specification of the management data unit (MDU) mapping for AMCC PtP WDM management channel;

- specification of the PtP WDM management frame format;

- functionality of the PtP WDM management PHY adaptation sublayer;

- the PtP WDM ONU activation cycle.