UMTS will build on the success of GSM and is likely to become even more widespread, increasing the importance of a
flexible network structure to permit the different operational configurations in which these networks will be deployed.
The requirements to have a RNC or BSC controlled by a single MSC server or SGSN lead to certain limitations.
Allowing the BSCs and RNCs to connect to a number of MSC servers or SGSNs increases the networks performance in
terms of scalability, distributing the network load amongst the serving entities, and reducing the required signalling as the user roams.
This document covers the details for the Intra Domain Connection of RAN Nodes to Multiple CN Nodes for GERAN
and UTRAN based systems. In particular, it details the impacts to GSM and UMTS systems and the stage 2 procedures
for the support of connecting a RNC or BSC to multiple MSC servers or SGSNs. The overall solution is described, and
the detailed impacts on the existing specifications are identified. The description of a broadly similar concept for EUTRAN based systems is not described in the document: instead, it is described in TS 23.401
Note: The specified solution impacts RAN nodes. In case an upgrade of radio networks is not performed, the
solutions for deploying NNSF functionality above RAN nodes described in TR 23.924
may be used
as a guideline for connecting RAN nodes to multiple MSC servers.
The reference model to which these procedures apply can be found within TS 23.002
. Detailed architectural
requirements within the subsystems are contained within the remainder of the 23 series of specifications e.g. the
requirements for the Packet Switched (PS) domain are contained within TS 23.060
and the requirements for the
Bearer Independent CS Core Network are contained in TS 23.205