Praise for Fundamentals of WiMAX

7.6 Summary and Conclusions 265Attempt NewReconstruction ofHeaderNoCRC correct?NoCounter Expired?YesYesForward PacketGive Up and RequestUpdateFigure 7.18 ROHC decompressor recovery processnetwork. This makes it difficult for an application to make the correct end-to-end bandwidthrequests for QoS.7.6 Summary and ConclusionsIn this chapter, we provided a brief overview of the various end-to-end aspects of broadbandwireless networks.• QoS is of two types: one based on per flow handling and one based on aggregate handling.Per flow handling offers better QoS but has scalability issues. Most IP networks today relyon aggregate handling.• The IETF has developed a number of architectures and protocols for providing QoS in anIP network. Three major emerging IP QoS technologies are integrated services, differentiatedservices, and multiprotocol label switching.• The session initiation protocol (SIP), a simple, flexible, and powerful text-based protocol,has rapidly established itself as the protocol of choice for multimedia session control in IPnetworks.• Wireless network designs should include support for basic security mechanisms, such asencryption, authentication, and access control. The IEEE 802.16e-2005, along with theWiMAX architecture, has support for robust and flexible security mechanisms.• To support mobile users, broadband wireless networks should incorporate mechanisms forlocation management and handoff management. Developing good handoff mechanisms iscritical to the performance of mobile networks.