tailieunhanh - Handbook of Applied Cryptography - chap12

This chapter considers key establishment protocols and related cryptographic techniques which provide shared secrets between two or more parties, typically for subsequent use as symmetric keys for a variety of cryptographic purposes including encryption, message authentication, and entity authentication. The main focus is two-party key establishment, with the aid of a trusted third party in some cases. While many concepts extend naturally to multi-party key establishment including conference keying protocols, such protocols rapidly become more complex, and are considered here only briefly, as is the related area of secret sharing. Broader aspects of key management, including distribution of public keys, certificates, and key life cycle issues, are deferred. | This is a Chapter from the Handbook of Applied Cryptography by A. Menezes P. van Oorschot and S. Vanstone CRC Press 1996. For further information see hac CRC Press has granted the following specihc permissions for the electronic version of this book Permission is granted to retrieve print and store a single copy of this chapter for personal use. This permission does not extend to binding multiple chapters of the book photocopying or producing copies for other than personal use of the person creating the copy or making electronic copies available for retrieval by others without prior permission in writing from CRC Press. Except where over-ridden by the specihc permission above the standard copyright notice from CRC Press applies to this electronic version Neither this book nor any part may be reproduced or transmitted in any form or by any means electronic or mechanical including photocopying microhlming and recording or by any information storage or retrieval system without prior permission in writing from the publisher. The consent of CRC Press does not extend to copying for general distribution for promotion for creating new works or for resale. Specihc permission must be obtained in writing from CRC Press for such copying. @1997 by CRC Press Inc. Chapter Key Establishment Protocols Contents in Brief Classification and Key transport based on symmetric Key agreement based on symmetric Key transport based on public-key Key agreement based on asymmetric Secret Conference keying .528 Analysis of key establishment protocols .530 Notes and further Introduction This chapter considers key establishment protocols and related cryptographic techniques which provide shared secrets between two or more parties typically for subsequent use as symmetric keys for a variety of .