Voice Communication Over All-IP Heterogeneous Wireless Networks: A Cross Layer Approach
2010
Hochschulschrift
Zugriff:
98
As Next Generation Network (NGN) technologies rapidly develop, various wireless access networks, such as LTE, WiFi and WiMAX, are expected to jointly support universal ubiquitous VoIP services for mobile users. In the near future, mobile users are expected to use multi-mode mobile devices to access VoIP services through Heterogeneous Wireless Networks (HWN). However, providing a high quality continuous VoIP service in HWN still faces many challenges, including mobility management, end-to-end QoS path establishment and voice playout buffer control. In traditional layered architectures (e.g., OSI and TCP/IP), protocols only communicate with adjacent layers and cannot get information from other nonadjacent layers. That is, they are only optimized in each layer. Thus, the performance of wireless VoIP services cannot be optimized in a layered protocol architecture. This dissertation presents a cross layer wireless VoIP service architecture for supporting high quality VoIP services over HWN. The proposed cross layer architecture utilizes IEEE Media Independent Handover (MIH) framework to perform the cross layer control. Cross layer algorithms and protocols are proposed to improve VoIP quality. A cross layer user motion aware handoff model is proposed to provide seamless handoff in HWN. A user motion detection (UMD) service uses a novel signal analysis model for integrating multiple signal processing sensors with machine learning technologies to analyze the received signal strength of a mobile device. Based on the motion detection results, the cross layer handoff events are sent to the upper layer protocols and wireless VoIP services to support seamless handoff and fast voice playout buffer adjustment. The end-to-end QoS communication path control in a VoIP call initiation procedure and a handoff procedure are also discussed. A cross layer intelligent session selection (ISS) service is proposed to optimize the VoIP communication path in terms of user requirements, including voice quality, monetary cost, power consumption and security, and the operating policies of service providers. A multi-criteria decision making model and related MIH-assisted voice session establishment protocols are presented. Finally, the voice playout buffer control for quality enhancement is discussed. A multiobjective optimization-based cross layer playout control scheme is proposed to minimize packet delay and packet loss rate and to enhance VoIP quality. Based on cross layer handoff event from the UMD service, VoIP applications can dynamically adjust VoIP performance.
Titel: |
Voice Communication Over All-IP Heterogeneous Wireless Networks: A Cross Layer Approach
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Autor/in / Beteiligte Person: | Chen, Yung-Mu ; 陳雍穆 |
Link: | |
Veröffentlichung: | 2010 |
Medientyp: | Hochschulschrift |
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