RANAP protocol is used in UMTS

Universal Mobile Telecommunications System

Universal Mobile Telecommunications System is a third generation mobile cellular technology for networks based on the GSM standard. Developed by the 3GPP , UMTS is a component of the International Telecommunications Union IMT-2000 standard set and compares with the CDMA2000 standard set for...

 signaling between the Core Network, which can be a MSC

Network Switching Subsystem

Network switching subsystem is the component of a GSM system that carries out call switching and mobility management functions for mobile phones roaming on the network of base stations...

 or SGSN, and the UTRAN

Utran

Utran is a census town in Surat district in the Indian state of Gujarat.-Geography:Utran is located at . It has an average elevation of 12 metres .-Demographics:...

. RANAP is carried over Iu-interface.

RANAP signalling protocol resides in the control plane of Radio network layer of Iu interface in the UMTS (Universal Mobile Telecommunication System) protocol stack. Iu interface is the interface between RNC (Radio Network Controller) and CN (Core Network). nb. For Iu-ps transport RANAP is carried on SCTP.

Functionality

RANAP is used for the following tasks:

• Relocation
• Paging
• Radio Access Bearer Management
• Transport of signalling between a UE and the Core Network (Non Access Stratum
  Non Access Stratum
  Non-access stratum is a functional layer in the UMTS wireless telecom protocol stack between a core network and user equipment.The layer supports signalling and traffic between those two elements. +- – - – - -+ +- – - – - – -+...
  
  signalling)