Section: 4.2 Composition of the Routing Area Identification (RAI)
Content: The Routing Area Identification shall be composed as shown in figure 4: Figure 4: Structure of Routing Area Identification The RAI is composed of the following elements: - A valid Location Area Identity (LAI) as defined in clause 4.1. Invalid LAI values are used in some special cases when no valid RAI exists in the mobile station (see 3GPP TS 24.008[ Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 ]  [5], 3GPP TS 31.102[ Characteristics of the Universal Subscriber Identity Module (USIM) application ]  [27] and 3GPP TS 51.011[ Specification of the Subscriber Identity Module - Mobile Equipment (SIM-ME) interface ]  [9]). - Routeing Area Code (RAC) which is a fixed length code (of 1 octet) identifying a routeing area within a location area.