Page 1320 - 5G Basics - Core Network Aspects

2 Transport aspects

1 Scope
This Recommendation specifies a flexible interoperable short-reach OTN interface, over which an OTUCn
(n ≥ 1) is transferred, using bonded interfaces. The FlexO interfaces are covered by application codes which
are at the time of publication 4I1-9D1F, 4L1-9C1F, C4S1-9D1F and 4L1-9D1F in [ITU-T G.695] and
[ITU-T G.959.1]. A FlexO group interface complements the existing functions specified in [ITU-T G.709], such
as B100G OTUCn frame, ODUk/flex, with new functions such as physical interface bonding, group
management and OTUCn (de)mapping. The intent of the FlexO Recommendation is to capture links to
existing [ITU-T G.709]/[ITU-T G.798] functions and to provide specifications for new functions that are
applicable to FlexO groups. In addition, some introduction material for the addressed application is
included.

2 References
The following ITU-T Recommendations and other references contain provisions which, through reference in
this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated
were valid. All Recommendations and other references are subject to revision; users of this
Recommendation are therefore encouraged to investigate the possibility of applying the most recent
edition of the Recommendations and other references listed below. A list of the currently valid ITU-T
Recommendations is regularly published. The reference to a document within this Recommendation does
not give it, as a stand-alone document, the status of a Recommendation.

[ITU-T G.695] Recommendation ITU-T G.695 (2015), Optical interfaces for coarse wavelength
division multiplexing applications.

[ITU-T G.709] Recommendation ITU-T G.709/Y.1331 (2016), Interfaces for the optical transport
network.
[ITU-T G.798] Recommendation ITU-T G.798 (2012), Characteristics of optical transport network
hierarchy equipment functional blocks.
[ITU-T G.870] Recommendation ITU-T G.870/Y.1352 (2016), Terms and definitions for optical
transport networks (OTN).
[ITU-T G.872] Recommendation ITU-T G.872 (2017), Terms and definitions for optical transport
networks.
[ITU-T G.959.1] Recommendation ITU-T G.959.1 (2016), Optical transport network physical layer
interfaces.

[ITU-T G.7041] Recommendation ITU-T G.7041/Y.1303 (2016), Generic framing procedure (GFP).
[ITU-T G.8260] Recommendation ITU-T G.8260 (2015), Definitions and terminology for
synchronization in packet networks.
[IEEE 802.3] IEEE Std. 802.3:2015, 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.
[OIF FlexE IA] Optical Interworking Forum, OIF (2016), FlexEthernet Implementation Agreement.

3 Definitions

3.1 Terms defined elsewhere

This Recommendation uses the following term defined elsewhere:

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