your RNC is connected to the other RNC thanks to an Iur link.
This Iur link has to be configured within each RNC :
– in RNC A : Iur from RNC A to RNC B
– in RNC B : from RNC B to RNC A
Typically, the iur’s configuration is defined on several layers (L1, L2, L3 (atm or ip) ), with correct addressings.
Then there are some radio parameters associated to Iur’s.
Then you define some external cells on those Iur links.
And then you define 3G-3G external relations that points to those external cells.