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Wireless networks are the answer for the interconnection of ubiquitous devices. However, wireless communications increase security challenges, privacy concerns and trust issues to the wireless access network, the mobile devices, the connected medical devices and the e-health applications (Grami & Schell, 2004). Wireless, mobile nodes are included in complex distributed systems which carry out basic network functions (packet forwarding, routing, and network management) (Chlamtac et al., 2003). Various protocols and algorithms are available for mobile ad hoc networks (Chlamtac et al., 2003) while quality of service models for mobile ad hoc networks and network security are significant challenges to be surveyed (Chlamtac et al., 2003). As a result, different quality of service constraints for various services illustrates the need for an automatic wireless technology option (Janevski, 2009).
Current generations of mobile phone networks (3G/UMTS and 4G) are based on packet-oriented architectures (Valtonen et al., 2004). Mobile telephony 3G licenses enable the delivery of web content to mobile consumers (Wilson, 2006). Users management involves subscriptions and profiles for different terminals (mobile phone, PDA, laptop) (Hong & Leon-Garcia, 2005) while the choice of a mobile phone is influenced by the provided mobile services (Shim & Shim, 2003).
Existing cellular and Wi-Fi networks merged with the Internet represent the 4th Generation (4G) wireless, mobile Internet networks (Gani et al., 2008). 4G generation of wireless intends to enhance and replace the 3G systems. 4G is a mobile network, IP-based, providing connection via always the best available network using seamless roaming and independent radio access technologies (Akhtar, 2008). In 4G mobile systems, different access technologies will be combined in the best possible way for different radio environments and service requirements (Hwang et al., 2007). 4G technologies are promising much larger data rates supporting full mobility (Perrucci et al., 2009) while enabling wireless connection and access to multimedia services with high-quality voice and high-definition video. 4G wireless telecommunication supports smart multimedia providing higher bit rate and wider bandwidth, 3D image technology, streamed HD TV with remote control, video multimedia and advanced multimedia messaging service (Huang et al., 2010). 4G is based on IPv6 (Akhtar, 2008). Mobile multimedia services provision requires a modern mobile communication system to make ubiquitous communication using mobile characteristics (Tachikawa, 2003). High quality voice, video, and data services can be delivered on a metropolitan scale using WiMAX (IEEE 802.16) with Wi-Fi (IEEE 802.11) as transition towards 4G (Santhi & Kumaran, 2006). Mobile WiMAX is expected to fulfill the goals of 4G technology offering full broadband mobility for all services (Santhi & Kumaran, 2006). In this context, global roaming and open interconnection interfaces are essential functions of 4G communications systems (He & Zhao, 2008).
4G will provide additional services (IP data casting) and advantages in terms of energy consumption, coverage, bandwidth and spectrum handling and will allow users to participate in a fully distributed or cellular-controlled fashion (Frattasi et al., 2005). All IP-based services for heterogeneous wireless access technologies, assisted by mobile IP, are expected to be provided by 4G mobile communication networks (Fu et al., 2004).