gement of those subscribers In cooperation with the radio access optimisation teams, the traffic profiles should also be characterised at the RNC level, with the target of achieving the correct mix of each and every one of the eight RNCs for every one of the SGSNs, in terms of optimal distributed connectivity of the Iu-PS interface links, assuming that the actual radio access topology should be kept unchanged. Hence there should be no modifications for Iu-b and Iu-r connectivity since it has already been optimised. Since both SGSNs are co-sited, the actual implementation of the optimisation exercise proposal can be undertaken as a simple re-homing exercise for the RNCs, normally carried out during the maintenance window overnight, with little - if any - disruption of the service. Topology Aspects It is also interesting to consider the optimisation possibilities arising from network topology aspects. Topology plays a self-evident role in radio access optimisation, but its role in packet core optimisation may not appear SO obvious at first glance. Not every network offers this kind of possibility. It is, in fact, related to the relative network size, with the larger networks offering more potential in this field. The most obvious topology optimisation subject for a packet core network can be seen as the strategic approach for deployment of the network nodes, be it a distributed architecture or a concentrated one. Obviously, the size of the network is the first aspect determining the architectural deployment strategy, since a network covering a small area such as a city state with a few tens of square kilometres, no matter the total amount of subscribers, will present a natural trend for a concentrated architecture, with all the packet core network nodes co-sited. It can be noted that during the early stages of deployment and growth of the network, it is easiest to have the nodes co-sited, since that greatly facilitates the implementation and operation of the network. However, as the subscriber base and traffic volu