3 Characterization of circuit telecommunication services

22.0013GPPPrinciples of circuit telecommunication services supported by a Public Land Mobile Network (PLMN)Release 17TS

3.1 General

A telecommunication service supported by a PLMN is characterized and described by service attributes.

There are two groups of service attributes applicable to user information flow:

– low layer attributes;

– high layer attributes.

Bearer services are characterized only by low layer attributes. Teleservices are characterized by both low layer attributes and high layer attributes.

The basic characteristics of a telecommunication service are described by the basic service attributes.

The additional characteristics associated with a supplementary service which modify or supplement a basic telecommunication service are described in Specification 3GPP TS 22.004 [7].

3.2 Bearer services

Bearer services are characterized by a set of low layer attributes in Specification 3GPP TS 22.002[5]. These attributes are classified into four categories:

– information transfer attributes;

– access attributes;

– interworking attributes;

– general attributes, including operational and commercial attributes.

The bearer capability defines the technical features of a bearer service as they appear to the user at the appropriate access point. For the time being, the bearer capability is characterized by information transfer, access and interworking attributes. A bearer capability is associated with every bearer service.

3.3 Teleservices

Circuit teleservices provide the full capacity for communication by means of terminals and network functions and possibly functions provided by dedicated centres.

Circuit teleservices are specified in 3GPP TS 22.003 [6]. Teleservices are characterized by a set of low layer attributes, a set of high layer attributes and operational and commercial attributes.

Low layer attributes are those used to characterize the bearer capability. High layer attributes are used in Specification 3GPP TS 22.003 [6] to describe high layer (i.e. layer 4-7) information transfer related characteristics. They refer to functions and protocols of layers 4-7 in the ITU-T Recommendation X.200 framework which are concerned with the transfer, storage and processing of user messages (provided by a subscriber’s terminal, a retrieval centre or a network service centre).

Therefore, not all attributes can be applied directly at the user to terminal interface as they represent two kinds of features, the bearer capability and the terminal features, that are not directly perceived by the user.