Page 1377 - 5G Basics - Core Network Aspects

Signalling aspects 3

1 Scope
This Recommendation describes the signalling requirements for the flexible network service combination on
broadband network gateway (BNG). The signalling supports the service routing, service combination, service
deployment and service provision on the BNG. This Recommendation focuses on the signalling between the
service platform and BNG. Signalling above the service platform is out of scope of this Recommendation.

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 Y.3300] Recommendation ITU-T Y.3300 (2014), Framework of software-defined networking.

3 Definitions

3.1 Terms defined elsewhere

This Recommendation uses the following terms defined elsewhere:
3.1.1 software-defined networking (SDN) [ITU-T Y.3300]: A set of techniques that enables users to
directly program, orchestrate, control, and manage network resources, which facilitates the design, delivery
and operation of network services in a dynamic and scalable manner.

3.2 Terms defined in this Recommendation

This Recommendation defines the following terms:
3.2.1 broadband network gateway (BNG): The access point to the provider's IP network for wireline
broadband services.
3.2.2 chrysanthemum service route path: A route path in which every packet is transferred back to the
original node from where it came when the network service handling is done.

3.2.3 hybrid service route path: A route path in which each packet is transferred either directly to the
next network service for handling, or to the original node when the network service handling is done.

3.2.4 lily service route path: A route path in which each packet is transferred directly to the next node
where network service is deployed for handling and it does not need to be transferred back to the original
node.
3.2.5 service chaining: A technique of linking together simpler service-enabling elements in an intended
order to create more complex services. The method of chaining may be composition, combination, etc.4.

4 Abbreviations and acronyms
This Recommendation uses the following abbreviations and acronyms:

AAA Authentication, Authorization and Accounting
A-RS-RSP Automatic Resource Status Response

API Application Programming Interface
BNG Broadband Network Gateway

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