Page 696 - 5G Basics - Core Network Aspects

2 Transport aspects

Table 5-5 – Summary of the FTU reference points defined in the Recommendation

Reference Category Brief description of information flow Reference
point
TPS-TC_MGMT Management/control, Management and control primitives exchanged Clause 8.1.3
bidirectional, between the TPS-TC and FME. These include
logical/functional parameters of TPS-TC and DTU size.
PMS- Management/control, Management and control primitives exchanged Clause 9.1.2
TC_MGMT bidirectional, between the PMS-TC and FME. These include
logical/functional parameters of FEC, framing and PMS-TC framing
overhead data.
PMD_ Management/control, Management and control primitives exchanged Clause 10.1.2
MGMT bidirectional, between the PMD and FME. These include
logical/functional parameters that determine bit loading, gain
adjustment, PSD shaping, TDD timing (TCE) and
vectoring (VCE).

The data plane protocol reference model of the ITU-T G.9701 link is shown in Figure 5-10 and corresponds
to the FTU protocol reference model shown in Figure 5-9.

Figure 5-10 – Data plane protocol reference model

5.4 FTU functional model

The FTU functional model is presented in Figure 5-11 and includes functional blocks and interfaces of the
FTU-O and FTU-R specified in this Recommendation. The model illustrates the most basic functionality of an
FTU and comprises an application-invariant part and an application-specific part. The application-invariant
part consists of the physical media specific part of the transmission convergence (PMS-TC) sub-layer and
the physical media dependent (PMD) sub-layer, which reside between α and U reference points and are
defined in clauses 9 and 10, respectively.

The application-specific part is confined to the transport protocol specific transmission convergence
(TPS-TC) sub-layer that resides between γ and α reference points; the γ reference point is the FTU
application interface. The TPS-TC sub-layer is described in clause 8 and includes one TPS-TC function
intended to present data packets of the corresponding application protocols to the unified application-
independent α reference point. These data packets carry application data that are intended to be
transmitted transparently to the corresponding application entity above the γ-reference point of the peer
FTU.
The FME contains all relevant FTU management functions, including those related to TPS-TC, PMS-TC and
PMD. The management primitives between the FME and upper-layer ME are exchanged via the γ_MC
interface. The γ_MC interface also communicates primitives between the FME and TCE, DRA and VCEs
function at the FTU-O, and PSE, TCE and DRRus functions at the FTU-R.

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