6 Network Characteristics

09.073GPPGeneral Requirements on Interworking between the Public Land Mobile Network (PLMN) and the Intergrated Services Digital Network (ISDN) or Public Switched Telephone Network (PSTN)TS

6.1 Key Characteristics of Networks Concerned

Table 1: Key Characteristics of Networks Concerned

Characteristic

GSM PLMN

ISDN

PSTN

Subscriber Interface

Digital

Digital

Analogue

User‑network signalling

GSM 04.08

DSS1, other UNIs

loop‑disconnect and DTMF

User‑terminal equipment supported

MT0, MT1 or MT2 functions (see GSM 04.02)

Digital TE
(ISDN NT, TE1 or TE2+TA)
see e.g. I.411

Analogue TE (e.g. dial pulse telephones PABXs modem equipped DTEs)

Inter‑exchange signalling

SS No.7 ISUP TUP+, MAP

SS No.7 ISUP TUP+, TUP, NUP

Channel associated
(e.g. R2, No.4, No.5) or common channel (e.g. No.6)

Transmission facilities

Digital

Digital

Analogue

Exchange types

Digital

Digital

Analogue/digital

Information transfer mode

Circuit

Circuit/Packet

Circuit

Information transfer capability

Speech, digital unrestricted, alternate speech/ group 3 fax etc.

Speech, digital unrestricted, 3,1 kHz audio, video etc.

3,1 kHz audio
(voice/voice‑ band data)

6.1.1 Characteristics of PLMNs

The GSM PLMN is fully defined in the GSM Technical Specifications.

6.1.2 Characteristics of PSTNs

Because of the efforts at an early stage to standardize ISDNs in different countries, the differences between any two ISDNs will be small compared with the differences between PSTNs, which have evolved in different ways in different countries. In some cases the evolution has occurred over many decades, and therefore each PSTN is distinct, and for a recommendation on interworking, it is necessary to make certain assumptions about a generalized PSTN.

Whilst the key characteristics of PSTNs are given in table 1 above, the specific MSC/IWFs needed to allow interworking between a PLMN and a PSTN will depend on the nature of the PSTN concerned.

Table 2 below gives a number of categories that can be used to classify PSTNs and a number of possibilities within each category.

Table 2: Characteristics of PSTNs

Category

Possibilities within Category

Type of subscriber

a) PSTN with loop disconnect subscriber signalling (10 pps)

signalling

b) PSTN with DTMF subscriber signalling

Type of interexchange

a) PSTN with channel‑associated signalling

signalling

b) PSTN with common‑channel signalling

Type of interexchange

a) Analogue

transmission

b) Digital

Type of exchange

a) PSTN with electro‑mechanical switching

switching

b) PSTN with electronic (non‑digital) switching

c) PSTN with electronic digital switching

Type of exchange

a) Non‑SPC

control

b) SPC

NOTE: Under each category, it is possible that a PSTN will have a combination of the possibilities rather than only one.

6.1.3 Characteristics of ISDN

For the "standardized ISDN" in principle taken into account here, these are defined in the ETS‑series.