Services are communication capabilities that are made available to the users by the Home Environment (HE) and the Serving Network(SN). The services are divided into four main classes:
Lets discuss each of them below
Bearer services in UMTS are negotiable (unlike GSM where they are not) and can be used flexibly by applications. Bearer services provide the capability for information transfer between access points and only lower layer functions. PS (see ) and CS (see ) domains provide a specific set of bearer capabilities.
Bearer services are charachterised by a set of end-to-end charachteristics with requirements on QoS. QoS (or Quality of Service) is the quality of the service that has been requested. The service charachteristics includes things like traffic type, supported bit rates and the quality of information. These parameters are negotiated when a connection is being established. If the network is unable to provide the required QoS, it will re-negotiate the QoS depending on what is available. After the connection has been established, if there is a need then these parameters can be re-negotiated again. The following are the brief description of the bearer services.
Teleservices provide the full capabilities for communications by means of terminal equipment, network functions and possibly functions provided by dedicated centres. Basically it is a service that provides complete end-to-end capability for communication between mobile users according to standards. Teleservices contain both single media and miultimedia services. Some of the teleservices are listed below
Teleservices utilises the bearer services provided by lower layers. The Bearer Services and the Teleservices are not coupled to each other so as to aid independent development and changes to one may not necessarily mean changes to other.
Supplementary Services (SS)
A supplementary service modifies or supplements a basic telecommunication service. Consequently, it cannot be offered to a user as a stand alone service. A stand alone service can be either Bearer Service or Teleservice but cannot be Supplementary service. It shall be offered together or in association with a basic telecommunication service. The same supplementary service may be applicable to a number of basic telecommunication services. Also, one basic telecommunication service may use several SS simultaneously.
The following is list of some of the supplementary services (see  for more details)
Services Capability Features are open, technology independent building blocks accessible via a standardised application interface. This interface shall be applicable for a number of different business and applications domains (including besides the telecommunication network operators also service provider, third party service providers acting as HE-VASPs, etc.). All of these businesses have different requirements, ranging from simple telephony and call routing, virtual private networks, fully interactive multimedia to using UE based applications. Since the API is standardised but not the services, Mobile operators can utilise the API to build unique value-added services.
Two different types of service capability features can be distinguished (see  for details:
Examples of Framework Service Capability features are
Examples of Non-Framework service capability features are
 3GPP TS 22.105: Service Aspects; Services and Service capabilities
 3GPP TS 23.107: Quality of Service (QoS) concept and architecture
 3GPP TS 22.002: Circuit switched Bearer Services supported by PLMN
 3GPP TS 22.060: General Packet Radio Service; Service Description; Stage 1
 3GPP TS 22.004: General on Suplementary Services
 3GPP TS 22.001: Principles of circuit telecommunication services supported by a Public Land Mobile Network
 3GPP TS 22.003: Circuit Teleservices supported by a Public Land Mobile Network
 3GPP TR 22.121: The Virtual Home Environment
 3GPP TS 22.038: SIM Toolkit; Stage 1
 3GPP TS 22.057: Mobile Execution Environment (MExE); Service Description; Stage 1
 3GPP TS 22.078: Customised Applications for Mobile network Enhanced Logic (CAMEL); Service Definition - Stage 1