the contents of a particular message or a TS several times. The reader may take the help of an experienced professional/colleague in this regard.
2.5.9 Standardization of Technical Specifications by 3GPP
Standardizations of technical specifications are required and important to design interoperable systems by different vendors/OEMs. Because of standardizations, one can use various telecommunications services from different service providers using varieties of handheld devices such as Mobile and POS terminal.
2.5.10 Scope of 3GPP Technical Specification (TS)
A particular 3GPP technical specification description may cover all the systems. A TS specifies its applicability/scope to other mobile communications systems such as the GERAN, UMTS, LTE, and 5G. Pay attention to this fact. For example, click on any specification series for a particular subject area on the 3GPP site [2]. All the technical specifications shall be presented under that particular series. Now, further, click on any technical specifications. A new window shall be opened, and from there, one can find the scope and applicability, under Radio Technology, of the technical specification being clicked. Below the Radio Technology, there is a link by clicking which all the versions/releases of the particular technical specification can be downloaded.
The first section of every technical specification also describes its scope. Moreover, the first page of every technical specification displays the GSM or LTE or LTE Advanced or 5G logo depending on the scope.
2.5.11 3GPP TS for General Description of a Protocol Layer
A 3GPP protocol layer may perform several important functions and procedures. The functions and procedures performed may be split into several individual technical specifications. For such a protocol layer, it contains an introductory technical specification too, for example, LTE TS 36.201 [89] and 5G NR TS 38.201 [105], which provides an overview and a general description of the concerned protocol layer. The introductory technical specification also describes the detailed relationships among the split technical specifications. It may be also noted that for the same protocol layer, for example, in the case of the UMTS physical layer, there may be separate technical specifications depending on its duplexing modes, i.e. Frequency Division Duplex (FDD) and Time Division Duplex (TDD), of transmission which is used by the physical layer.
However, in the LTE and 5G NR system, no separate technical specification is used to describe the physical layer functions and procedures working in the TDD and FDD mode.
2.5.12 3GPP TS Drafting Rules: Deriving Requirements
To derive various technical, functional, and other requirements without any ambiguity, the contents of a 3GPP technical specification should be understood and decoded properly. A 3GPP technical specification description contains the following types of requirements.
Normative
Such requirements must be complied with.
Informative
Such requirements if ignored, it does not matter. Note that a technical report is always an informative one.
To identify the above requirement types, a 3GPP specification/text description may contain the following auxiliary verbs:
Shall/Shall not – This is a normative and implies a mandatory requirement.
May/Need not – This is a normative and optional requirement.
Should/Should not – This is a normative and Recommendation requirement.
Can/Cannot – This is a normative and possibility/capability requirement.
Also, a 3GPP technical description is described using an active voice rather than a passive voice. For example, “The MS shall perform…” rather than the “…routing area update shall be performed by the MS”.
2.5.13 Download 3GPP Technical Specifications
1 Visit the 3GPP site [2].
2 Select a subject/area and the particular technical specification series. Select a technical specification of interest to download. Click on the Click to see all versions of this specification to download a specification for a particular release.
2.5.14 3GPP Change Requests
An introduction of a new feature as part of a release is documented in the form of a Change Request. The affected technical specifications due to a new feature are captured under a particular Change Request. Given a Change Request number, the affected technical specifications may be downloaded from the 3GPP portal https://portal.3gpp.org/ChangeRequests.aspx. One can find the relevant changes introduced in each affected technical specification due to a new 3GPP feature.
2.5.15 Learnings from 3GPP Meetings TDocs
Many technical documents (TDocs) in the form of written contributions are produced as a result of various meetings held among the 3GPP technical specifications working groups mentioned in Section 2.5.2 and other stakeholders. To produce a version of a technical specification, numerous meetings are held. Visit the 3GPP site [2] and follow the steps mentioned in the previous section. Click on the tab Versions. Look at the Meetings column under a particular Version. Click on any Meeting number to display the various written contributions (TDocs) under the “List of TDocs” link. A TDoc or a written contribution contains highly technical discussions, observations, and proposals, in a particular area/topic of the concerned technical specification. One can acquire a great deal of knowledge from such a TDoc, which can be used as supplementary information. If a particular aspect is not clear from a technical specification, a TDoc may be referred for more information on the related area.
2.6 3GPP Releases and Its Features
The 3GPP technical specifications are organized into different versions called “releases”, such as Release 99, Release 4, Release 5, Release 6, Release 7, Release 8, Release 9, Release 10, Release 11, Release 12, Release 13, Release 14, Release 15 and beyond. Various features introduced in each 3GPP releases are summarized in Table 2.3.
Some of these 3GPP releases involve the SAE right from the GSM to the 5G system as described earlier in Section 2.3. However, some of these releases involve the introduction of additional features only to improve the existing data transmission rates. New functionality or enhancement to an existing release is also added in each subsequent release. The Release 99, shown in Figure 2.10, was the first version where UMTS came into existence which evolved from the GSM/GPRS system in terms of the new RAN, UTRAN. Subsequent releases of the UMTS UTRAN introduced new features offering increased data transmission rates. Similarly, 3GPP Release 8 was the first version
