RNSAP¶

Radio Network Subsystem Application Part

RNSAP (Radio Network Subsystem Application Part) is a 3GPP signalling protocol responsible for communications between RNCs Radio Network Controllers defined in 3GPP specification TS 25.423.[1] It is carried on the lur interface and provides functionality needed for soft handovers and SRNS (Serving Radio Network Subsystem) relocation (handoff between RNCs).It defines signalling between RNCs, including SRNC(Serving RNC) and DRNC(drift RNC).

SRNC

DRNC

IUR

\ RNSAP

RNSAP

Converge protol

AAL 5

AAL5\ ATM

ATM\ Physical links------→→→ Physical links

RNSAP Layer Architecture