Evaluation of two integrated signalling schemes for the Ultra Flat Architecture using SIP, IEEE 802.21, and HIP/PMIP protocols

Telecommunication suppliers predict a huge mobile Internet traffic increase for the next decade. It seems to be technically challenging and expensive to adapt current mobile network architectures to the increasing traffic demand. Core network technology must scale to the demands under limited revenue growth. This work is to discuss a new, flat, fully distributed and convergent network architecture, called Ultra Flat Architecture. It is well scalable due to the distribution of IP and numerous control functions at intelligent gateways placed within or close to the base stations. This paper focuses on the detailed presentation of two relevant integrated signalling schemes of the architecture. These schemes extend the Ultra Flat Architecture to support legacy Internet applications including IMS compliant applications with all necessary network functions, such as security, mobility, and Quality of Service. Besides Session Initialization Protocol, layers 2 and 3 are taken into account as well, in the terminal attachment and handover procedures. IP mobility is provided by the Host Identity Protocol or the Proxy Mobile IP protocol in the two schemes. We analyse the suitability of the schemes using the Multiplicative Analytic Hierarchy Process. Both schemes have nearly the same performance, however the HIP-based scheme got slightly better scores under our evaluation criteria due to its stronger security and fewer functional modules to deploy.