6544

6109

كارشناسي ارشد

مخابرات

اصفهان: دانشگاه صنعتي اصفهان، دانشكده برق و كامپيوتر

1390

هشت، 96ص.: مصور، جدول، نمودار

ص.ع. به فارسي و انگليسي

مهدي برنجكوب

14/1/90

فرامرز هندسي، علي فانيان

1396/10/10

كتابنامه

برق و كامپيوتر

مهندسي برق و كامپيوتر

ID6109

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

A Proposed Secure Scheme for Handoff between Independent WISPs in Multi Operator Networks Mehdi Sharifi Sedeh m sharifisedeh@ec iut ac ir Date of Submission 2011 10 24 Department of Electrical and Computer Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Persian Supervisor Mehdi Berenjkoub brnjkb@cc iut ac irAbstract Abstract The role of internet in our life is increasing rapidly Anytime and anywhere access tointernet service is a main desire of users Sometimes and due to various reasons such as heavy traffic ortechnical problems a primary Wireless Internet Service Provider i e primary WISP might not be able toprovide internet service for new customers If another WISP i e secondary WISP can provide therequester with internet service at the same time a proposal is to transfer the user to the new WISP In thisthesis we propose a novel secure scheme for handoff between independent WISPs in multi operatornetworks These WISPs belong to different network operators Designed protocols for the proposed schemeinclude Token purchase protocol Handoff and payment protocol Clearance and deposit protocol and Dispute resolution protocol In addition to traditional internet service our approach includes emergingreal time and interactive services The proposed scheme uses a Financial Intermediary FI to handle offlinefinancial transactions such as token purchase clearance and deposit Payment method of our scheme is atoken based method in which tokens can be purchased by primary WISP from FI for the user to pay thesecondary WISP for providing internet service The secondary WISP can cash the collected tokens in theFI The micropayment method of our payment system is well extendable to macropayment method throughsubmitting more than one token in each payment Since we apply the hash chain technique to generatetokens there is no risk of credit loss in the clearance and deposit phase Furthermore any dispute amongentities is solvable in this scheme We applied symmetric key cryptography for secure communicationbetween user and new WISP The shared key between the user and new WISP is generated according toDiffie Hellman Key exchange algorithm Second handoff occurs when the new WISP is unable to continueproviding the user with the internet service For such a situation the second handoff and payment protocol is developed Furthermore the proposed scheme provides mutual authentication user anonymity user untraceability confidentiality non repudiation double spending prevention and joint key controlservices and is secure against deposit case attack that some previous roaming schemes are knownvulnerable to it Keywords Handoff WISP Payment system Token Security

مهدي برنجكوب

فرامرز هندسي، علي فانيان