It is only after expensive computations necessary for

Info icon This preview shows pages 62–64. Sign up to view the full content.

View Full Document Right Arrow Icon
natures.” It is only after expensive computations necessary for verification, can the unfortunate receivers realize that the signature is invalid. In general, MANET devices will need to employ several key distribution schemes for different types of security associations, for different network layers. In other words, every mobile device may be assigned many sets of secrets, used for different purposes. However, as we shall see in Section 4.3, it is desirable to ensure that some secrets assigned to a mobile device are protected even from the user of the device. We shall also see that in such scenarios, it is very much desirable to keep the computational overhead for operations performed with such protected secrets to very low levels. 4.3. Protection of Secrets The computers taking part in any network can be broadly classified into 1) network hosts; and 2) routers. In conventional networks like the Internet, computers have very well defined tasks. Network hosts are clients or servers Copyright © 2010. World Scientific Publishing Company. All rights reserved. May not be reproduced in any form without permission from the publisher, except fair uses permitted under U.S. or applicable copyright law. EBSCO Publishing : eBook Collection (EBSCOhost) - printed on 2/16/2016 3:46 AM via CGC-GROUP OF COLLEGES (GHARUAN) AN: 340572 ; Beyah, Raheem, Corbett, Cherita, McNair, Janise.; Security in Ad Hoc and Sensor Networks Account: ns224671
Image of page 62

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
50 M. Ramkumar that exchange application data. The broad purpose of a host is to satisfy the needs of the user employing the host. On the other hand, routers are computers that are entrusted with the task of routing packets between net- work hosts. Routers thus perform the “selfless” task of serving other hosts. Internet routers are typically managed by organizations with substantial infrastructural backing, and are thus implicitly trusted by all hosts. In contrast, in ad hoc networks, most computers will simultaneously perform the roles of network hosts and routers. It is thus instructive to see every mobile device that takes part in ad hoc networks as consisting of two agents 15 - a user agent, and a network agent. The “selfish” user agent works only on behalf of the owner of the mobile device to send application data to other mobile computers, and thus carries out tasks performed by a host (a client or a server) in conventional networks. The “selfless” network agent works for the entire network to route packets between user agents, and thus performs the task performed by routers in conventional networks. For this purpose network agents are expected to strictly comply with co-operative routing protocols. Ideally, users with selfish interests should not be able to 1) impersonate the network agent to send misleading routing information; or 2) modify the tasks entrusted to the network agent. Thus the network agent tasks should (ideally) be carried out inside the confines of a tamper-responsive d trusted boundary.
Image of page 63
Image of page 64
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern