RNSAP


RNSAP is a 3GPP signalling protocol responsible for communications between RNCs Radio Network Controllers defined in 3GPP specification TS 25.423. It is carried on the lur interface and provides functionality needed for soft handovers and SRNS relocation. It defines signalling between RNCs, including SRNC and DRNC.

SRNC | DRNC
| IUR |
RNSAP | RNSAP
| | |
Converge protol | Converge protol
| | |
AAL 5 | AAL5
ATM | ATM
Physical links------→→→ Physical links
RNSAP Layer Architecture

Procedures


This set of procedures is used to handle mobility with in the UTRAN.This is the most important of the RNSAP procedures. The
procedures belonging to this set includes SRNC relocation, inter-RNC cell update and UTRAN registration area update.

This set of procedure used to handle dedicated channel traffic between two RNCs. Unlike the basic mobility procedures which is used only for signalling, this set of procedures provides support for data transfer over the Iur interface. The data transfer takes place using a frame protocol. The procedures belonging to this set include establishment, modification and release of dedicated channel in the DRNC due to hard and soft handover, set-up/release of dedicated transport connections over Iur interface and data transfer for dedicated channels.
This set of procedures is used to handle common and shared channel traffic between two RNCs. In particular, this set of procedures facilitates the set-up and release of common channel transport connections over the
Iur interface.
Implementation of this is considered as optional.

Summary of Functions