7/21/2019 SRNC Relocation

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CRNC: Controlling RNCSRNC: Serving RNCDRNC: Drift RNC 

SRNC and DRNC are concepts that are tied to a UE-UTRAN connection on the Uu interface. In other ords! an SRNC serves aparticular UE and "anages the connections toards that UE. #i$eise! DRNC fulfills a si"ilar role to the SRNC e%cept that it isinvolved onl& in the case of a soft handover. Thus the UE initiall& starts a connection ith an RNC that 'eco"es its SRNC. If the UE "oves toards a cell edge! SRNC "a& decideto put the UE in soft handover state. If the ne R#s added to UE(s Active Set are under the control of a different RNC! that RNC

'eco"es the DRNC. The ter"s CRNC! SRNC and DRNC are onl& logical definitions 'ased on functionalit&. )h&sicall&! an RNC "a& 'e a CRNC*SRNC orCRNC*DRNC. CRNC is responsi'le for the controlling the resources of a Node-+. It "anages co""on transport resources! code allocation! load andcongestion control. If ne radio lin$s ,R#s are to 'e esta'lished CRNC does the o'. SRNC "anages the connection to the UE and "aintains the UE conte%t ithin UTRAN. ,/or this purpose! S-RNTI allocated to the UEidentifies the UE uni0uel& ithin the SRNC. This identit& is "anaged '& the SRNC and ill 'e reallocated during SRNC Relocation.Thus! outer loop poer control! handover and RANA) signalling are "anaged fro" the SRNC.

DRNC "anages resources under its control 'ut relies on SRNC for "ost decisions and co""ands.

 

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SRNC Relocation

 

In /igure! the UE is in S12 in hDRNC. As the UE continues to "are no under the DRNC ,/igure Since the SRNC no longer "anapoint it decides to transfer the coDRNC 'eco"es the SRNC. The

the CN.

It is ala&s the SRNC that "anala&er in UTRAN resides in the SRpara"eters to air interface transpprocedure is invo$ed ithin the Sconnection ith the UE. 4hile the UE is in Inter-RNC S1DRNC. The DRNC routes data trDRNC "a& optionall& ,if configurdata 'eteen Iu' and Iur interfacalso distri'utes the processing lo'e considerations on hich the Sthe DRNC. Naturall&! co"'ining t&pes of data co"'ining is possi''ased on 0ualit& infor"ation ass