The progress of future generation communication relies not only on
developing new wireless radio access technologies, but also on the  internetwoking of  existing heterogenous networks to meet the
requirements of evloutionary mobile broadband and multimedia applications. The
ever increasing demands of wireless generations, force researchers to develop
newer heterogenous internetworking system, with enhanced Quality of Service
(QoS) to provide users with seamless access across diverse services, and devices.
Several exiting  Fourth Generation (4G), Third
Generation (3G) and Third Generation Partnership Project (3GPP) technologies
were integrated to work under the common IP Multimedia Subsystem (IMS)
architecture, to provide enriched, robust multimedia services across diverse
access technologies. A reliable internetworking framework to satisfy the futre
demands however, exists with  major
research issues involving seamless mobility management, integration and interoperability of
diverse networks, enhancing spectrum efficiency and channel
capacity along with ubiquitous coverage and QoS
maintenance. With the
enlarging demands of the mobile broadband  with years, the internetworking
of heterogeneous networks should have a widely deployed mechanism that ensures
seamless end-to-end QoS, as the users interact
with different QoS management mechanisms and policies while moving from one access network to another.The main objective of this research work
is to provision a scalable QoS framework for wireless  users with a 
refined  end-to-end  QoS requirements, over  the future converged  heterogeneous networks. QoS provisioning framework
was developed for the heterogenous 
intenetworking hybrid coupled 3GPP2 (Ultra Moile Boadband (UMB)), IEEE
802.16e (Worldwide Interoperability for Microwave Access  (WiMAX)) , and IEEE
802.11g (Wireless Local Area Network (WLAN)). This research work investigates
on the  performance of the hybrid coupled
UMB-WiMAX-WLAN internetworking architecture with varoius end-to-end  QoS proivioning methods such as load
balancing, radio resource management,
mobility management and capacity improvement through power
mangement techniques.

A novel Intelligent Interworking Protocol (IIP)
system is proposed to interwork the  hybrid coupled UMB-WiMAX-WLAN architecture.
IIP, is a unified architecture developed to improve the service performance of
future technology that meets the requirement in obtaining a network that
enhances the service metrics through reduced latency to milliseconds,  and with increased data rate.  It  is
developed to be an  unified architecture
of various service levels , by 
converging the  multimedia, and  application server layers with  Call Session Control Function (CSCF) layer of
the exiting core IMS architecture. It is also added with additional
functionalities such as Emergency- Call Session Control Function (E-CSCF), Service
Centralization and Continuity application Server (SSC-AS), Breakout Gateway
Control Function (BGCF) and Internet Protocol Multimedia Service Switching
Function (IMSSF),etc., to improve the multimedia service switching function and
to use the unutilized channels to increase the capacity of the network.  With different functional elements of the
integrated heterogeneous future technology the proposed IIP can be used to
develop a cost effective internetworking architecture with high flexibility and
reliability.  The internetworking
architecture of hybrid coupled UMB-WiMAX-WLAN is developed with the IIP for the
proposed architectures and algorithms are simulated using OPNET 14.5.  The proposed hybrid coupled UMB-WiMAX-WLAN-IIP
Internetworking architecture is compared with the hybrid coupled UMB-WiMAX- WLAN interworking using core
IMS and existing UMTS-WiMAX-WLAN scenarios. The QoS performance metrics of conversational,  interactive and background applications, such
as Voice, Video,  Email,  File Transfer Protocol (FTP), and Web Browsing
(Hyper text Transfer Protocol (HTTP)) are obtained and compared between proposed
and existing scenarios.