SGSN Pool Networking

SGSN Pool Networking

The prerequisite of the SGSN pool networking is that the connections in the network use the Gb over IP or Iu over IP bearer mode. All SGSNs and base station controllers/radio network controllers (BSCs/RNCs) must be logically connected. If the connections use the time division multiplexing (TDM) or asynchronous transfer mode (ATM) bearer mode, the whole interconnection may be not implemented because of limited transmission resources, particularly in the case when the SGSNs are directly connected to the radio access network (RAN). Therefore, the SGSN pool networking scheme only takes the IP bearer into account.

The basic requirements of the networking are as follows:

• Each RNC rather than the BSC/packet control unit (PCU) possesses independent signaling point coding.
• Each SGSN possesses independent signaling point coding.
• The MTP3 User Adaptation Layer (M3UA) link data must be configured between the RNCs and the SGSNs.
• The SGSNs and the RNCs/BSCs are all connected at the IP layer.

The Iu/Gb interface between an RNC/BSC and an SGSN uses the IP bearer mode.

Typical networking of the SGSN pool:

This Pic shows the typical all-IP networking. The RNCs/BSCs in an equipment room are connected to the SGSNs through a local area network (LAN). The RNCs/BSCs in different equipment rooms are connected to the SGSNs through an IP backbone network.