In this network era, the need for an user to always best connected with optimize services called as Always Optimized Connected (AOC). To execute a vertical handoff decision for perfect and effective services continuity and quality of services (QoS), different type of multi-displinary algorithms had been proposed for addressing this problem. The comparative analysis of these methods including SAW,MEW,TOPSIS,ELECTRE,VIKOR,GRA,WMC,AHP have been studied showing their performance for different application (i.e. voice, data )with decision factors such as received signal strength(RSS),available bandwidth, service type, monetary cost ,network condition and user choice.

1. Jose D. Mart´?nez-Morales, Ulises PinedaRico,Enriqu Stevens-avarro, “Performance comparison between MADM Algorithm for Vertical Handoff in 4G Networks” 2010 7th International Conference on Electrical Engineering, Computing Science and Automatic Control (CCE 2010) Tuxtla Gutiérrez, Chiapas, México. September 8-10, 2010 [2 ] L. Wang and D. Binet, “MADM-based network selection in heterogeneous wireless networks: a simulation study,” VITAE’09
2. Phuoc Nguyen Tran, Nadia Boukhatem ,Computer Science & Network Department ,”Comparison of MADM Decision Algorithms for Interface Selection in Heterogeneous Wireless Networks” , ParisTech 46 rue Barrault, 75013 Paris, France
3. Y. Wang, P. Zhang, Y. Zhou, J. Yuan, F. Liu, and G. Li, “Handover Management in Enhanced MIH Framework for Heterogeneous Wireless Networks Environment,” Journal of Wireless Personal Communications,vol.52, no. 3, pp. 615-636, Feb. 2010.
4. Gowrishankar, G. T. Raju, and P. S. Satyanarayana, “Perform ability Model of Vertical Handoff in Wireless Data Network,” in Proc. of 4th International Conf. on Wireless and Mobile Communications, ICWMC’08
5. K. Yoon and C.L. Hwang, Multiple Attribute Decision Making Methods Applications, Spring Verlag, 1981
6. K. Yoon and C.L. Hwang, Multiple Attribute Decision Making Introduction, Sage Publication, 1995
7. S. Chakraborty and C.Yeh, A Simulation Based Comparative Study of Normalization Procedures in Multi-attribute Decision Making, the 6th WSEAS Int. Conf. on Artificial Intelligence, Knowledge Engineering and Data Bases , Corfu Island, Greece, February 16-19, 2007
8. K.Savitha, C.Chandrasekar, Trusted NetworkSelection using SAW and TOPSIS Algorithms for Heterogeneous Wireless Networks International Journal of Computer Applications (0975 – 8887),Volume 26– No.8, July 2011
9. R.Tawil, G.Pujolle and O.Salazar, “Vertical Handoff Decision Schemes For The Next Generation Wireless Networks”, Wireless Communications and Networking Conference, 2008, pp. 2789-2792.
10. www.csi.com, computer society of india.

Vertical handoff decision Multi-displinary Always Oplimaized Connected (AOC) 4G wirelessnetwork