An RNC node is uniquely identified by its RNC Identifier (RNC-Id). The RNC-Id of an RNC is used in the UTRAN, in
a GERAN which is operating in GERAN Iu mode and between them. A BSC which is part of a GERAN operating in Iu
mode is uniquely identified by its RNC Identifier (RNC-Id). The RNC‑Id of a BSC is used in a GERAN which is
operating in GERAN Iu mode, in the UTRAN and between them. RNC-Id together with the PLMN identifier globally
identifies the RNC.
The RNC‑Id on its own or the RNC‑Id together with the PLMN‑Id is used as the RNC identifier in
the UTRAN Iub, Iur and Iu interfaces. The SRNC‑Id is the RNC‑Id of the SRNC. The C‑RNC‑Id is the RNC‑Id of the
controlling RNC. The D‑RNC‑Id is the RNC‑Id of the drift RNC.
The RNC-Id is defined by the operator, and set in the RNC via OAM.
For the syntax description and the use of this identifier in RANAP signalling, see TS 25.413.
A PLMN-specific regional subscription defines unambiguously for the entire PLMN the regions in which roaming is
allowed. It consists of one or more regional subscription zones. The regional subscription zone is identified by a
The elements of the RSZI are:
the Country Code (CC) which identifies the country in which the PLMN is located;
the National Destination Code (NDC) which identifies the PLMN in that country;
the Zone Code (ZC) which identifies a regional subscription zone as a pattern of allowed and not allowed
location areas uniquely within that PLMN.
CC and NDC are those of an ITU-T E.164 VLR or SGSN number of the PLMN.