6 Other Iuant interface specifications

37.4603GPPIuant interface: General aspects and principlesRelease 17TS

6.1 Iuant interface: Layer 1 (TS 37.461)

TS 37.461 [2] specifies the standards allowed for implementation of Layer 1 (physical layer) on the Iuant interface.

6.2 Iuant interface: Signalling Transport (TS 37.462)

TS 37.462 [3] specifies the signalling transport related to RETAP and TMAAP signalling to be used across the Iuant interface.

6.3 Void

6.4 Summary of Iuant interface Technical Specifications

The relationship between the technical specifications that define the Iuant interface is shown in figure 6.4.1.

Figure 6.4.1: Iuant Interface Technical Specifications

6.5 Iuant interface: Application part specification (TS 37.466)

TS 37.466 [7] specifies protocols for application part to be used over the Iuant interface.

Annex A (informative):
OSI model overview

Figure A.1: Relevant OSI model layers

Figure A.1 shows the relevant OSI model layers and the communication paths between the primary and secondary device.

The two important aspects of the OSI model are:

– It defines a layered structure for the communication software;

– It provides each layer with an apparent direct link to the same layer at the other device.

However, in real life, the only actual message path between the two devices is through the physical connection between the two layer 1 entities.

The layer 2 entities appear to communicate directly. In actual fact, a message passed from the first device to the second device takes the following path:

– Layer 2 at the first device passes the message down to Layer 1;

– Layer 1 transmits the message across the physical connection (for instance a wire) to layer 1 at the second device;

– Layer 1 at the second device passes the message up to Layer 2 at the second device.

Likewise, layer 7 entities appear to communicate directly. In actual fact, a message passed from the first device to the second device takes the following path:

– Layer 7 at the first device passes the message down to Layer 2;

– Layer 2 at the first device passes the message down to Layer 1;

– Layer 1 transmits the message across the physical connection (for instance a wire) to layer 1 at the second device;

– Layer 1 at the second device passes the message up to Layer 2 at the second device;

– Layer 2 at the second device passes the message up to Layer 7 at the second device.

Annex B (informative):
Change History

Change history
Date	Meeting	TDoc	CR	Rev	Cat	Subject/Comment	New version
2019-02	R3-103	R3-190079				Text transferred from 25.460 v15.0.0 (changes shown with rev marks)	1.15.0
2019-04	RAN#83	RP-190582				Specification approved by RAN plenary	15.1.0
2019-12	RP-86	RP-192915	0001	5	F	Correction for Iuant	15.2.0
2020-07	RAN#88-e	–	–	–	–	Update to Rel-16 version (MCC)	16.0.0
2022-03	RAN#95-e	RP-220238	0002	1	D	Inclusive language review	17.0.0