Dynamic Resource Allocation for Improved QoS in WiMAX/WiFi Integration
Wireless access technology has come a long way in its relatively short but remarkable lifetime, which has so far been led by WiFi technology. WiFi enjoys a high penetration in the market.Most of the electronic gadgets such as laptop, notepad, mobile set, etc., boast the provision ofWiFi. Currently most WiFi hotspots are connected to the Internet via wired connections (e.g., Ethernet), and the deployment cost of wired connection is high. On the other hand, since WiMAX can provide a high coverage area and transmission bandwidth, it is very suitable for the backbone networks of WiFi. WiMAX can also provide the better QoS needed for many 4G applications. WiMAX devices, however, are not as common as WiFi devices and it is also expensive to deploy aWiMAX-only infrastructure. An integrated WiMAX/WiFi architecture (using WiMAX as backhaul connection for WiFi) can support 4G applications with QoS assurance and mobility, and provide high-speed broadband services in rural, regional and urban areas while reducing the backhaul cost. WiMAX and WiFi have different MAC mechanisms to handle QoS. WiMAX MAC architecture is connection-oriented providing the platform for strong QoS control. In contrast,WiFi MAC is not connection-oriented, hence can provide only best effort services. Delivering improved QoS in an integrated WiMAX/WiFi architecture poses a serious technological challenge. The paper depicts a converged architecture of WiMAX and WiFi, and then proposes an adaptive resource distribution model for the access points. The resource distribution model ultimately allocates more time slots to those connections that need more instantaneous resources to meet QoS requirements. A dynamic splitting technique is also presented that divides the total transmission period into downlink and uplink transmission by taking the minimum data rate requirements of the connections into account. This ultimately improves the utilization of the available resources, and the QoS of the connections. Simulation results show that the proposed schemes significantly outperform the other existing resource sharing schemes, in terms of maintaining QoS of different traffic classes in an integratedWiMAX/WiFi architecture.
Unable to display preview. Download preview PDF.
- 1.WiMAX and WiFi Together: Deployment Models and User Scenarios, http://www.motorola.com/staticfiles/Business/Solutions/Industry%20Solutions/Service%20Providers/Wireless%20Operators/Wireless%20Broadband/wi4%20WiMAX/_Document/StaticFile/WiMAX_and_WiFI_Together_Deployment_Models_and_User_Scenarios.pdf (last accessed July 8, 2010)
- 3.Mangold, S., Habetha, J., Choi, S., Ngo, C.: Co-existence and Interworking of IEEE 802.11a and ETSI BRAN HiperLAN/2 in MultiHop Scenarios. In: Proc. of IEEE 3rd Workshop in Wireless Local Area Networks, Boston, USA, September 27-28 (2001)Google Scholar
- 4.Berlemann, L., Hoymann, C., Hiertz, G.R., Walke, B.: Unlicensed Operation of IEEE 802.16: Coexistence with 802.11(A) in Shared Frequency Bands. In: 2006 IEEE 17th International Symposium on Personal, Indoor and Mobile Radio Communications, September 11-14, pp. 1–5 (2006)Google Scholar
- 5.Berlemann, L., Hoymann, C., Hiertz, G.R., Mangold, S.: Coexistence and Interworking of IEEE 802.16 and IEEE 802.11(e). In: Proc. of IEEE 63rd Vehicular Technology Conference, VTC 2006-Spring, Melbourne, Australia, May 7-10 (2006)Google Scholar
- 6.Hui-Tang, L., et al.: An Integrated WiMAX/WiFi Architecture with QoS Consistency over Broadband Wireless Networks. In: 6th IEEE Consumer Communications and Networking Conference, CCNC 2009 (2009)Google Scholar
- 7.Gakhar, K., Gravey, A., Leroy, A.: IROISE: a new QoS architecture for IEEE 802.16 and IEEE 802.11e interworking. In: 2nd International Conference on Broadband Networks, BroadNets 2005, October 7, pp. 607–612 (2005)Google Scholar
- 12.Shi, J., Hu, A.: Maximum Utility-Based Resource Allocation Algorithm in the IEEE 802.16 OFDMA System. In: IEEE International Conference on Communications, ICC 2008, May 19-23, pp. 311–316 (2008)Google Scholar
- 14.Siddique, M.A.R., Kamruzzaman, J.: VoIP Capacity over PCF with Imperfect Channel. In: IEEE Global Telecommunications Conference, GLOBECOM 2009, November 30-December 4, pp. 1–6 (2009)Google Scholar
- 15.Siddique, M.A.R.: Voice Quality Framework for VoIP over WLANs, PhD thesis, GSIT, Monash University, Australia (2011)Google Scholar